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May 31, 2004
Drusenoid PED, metamorphopsia affect AMD prognosis
Large drusenoid pigment epithelium detachment and metamorphopsia are risk factors for progression of choroidal neovascularization in age-related macular degeneration, according to a long-term study. Drusenoid pigment epithelium detachment (PED) for a mean of 4.6 Drusenoid PED is defined as 0.5 disc diameter of confluent soft drusen under the center of the macula. Eyes with drusenoid PED had a 50% chance of developing geographic atrophy after 7 years. If the drusenoid PED is greater than 2 disc diameters upon presentation, progression to atrophy or ingrowth of CNV will occurre after 2 years (P < .01). At follow-up of more than 10 years, three-quarters of eyes with drusenoid detachments will progress to geographic atrophy and one-quarter to CNV. Optical coherence tomography is helpful in distinguishing between coalescent soft drusen and drusenoid PED.
Posted by kjalali at 09:22 PM
Vitrase granted U.S. approval for use as spreading agent in anesthesia
Hyaluronidase will be available commercially in the United States for the first time in 3 years, following announcement of the regulatory approval of Vitrase from Ista Pharmaceuticals.U.S. regulators approved Vitrase (ovine lyophilized hyaluronidase for injection) for use as a spreading agent to help with the dispersion and absorption of other drugs, according to a press release from the product’s marketer.A previously available version of hyaluronidase, the Wyeth drug Wydase, was widely used in ophthalmic anesthesia before it was withdrawn from the market in 2001. A press release from Ista reported that before 2001, Wydase was used as a spreading agent in more than 750,000 ophthalmic surgeries annually.Ista Pharmaceuticals noted in its release that the approval of Vitrase removes hyaluronidase from the Food and Drug Administration’s drug shortage list, where it has been since 2001. Vitrase is highly purified, preservative-free ovine hyaluronidase, according to the release.
Posted by kjalali at 09:02 PM
May 29, 2004
Improved functional vision with a modified prolate intraocular lens
JCRS MAY 2004
To evaluate whether the Tecnis Z9000 intraocular lens (IOL) (Pfizer) with a modified prolate anterior surface provides better quality of vision than a conventional spherical IOL.
USA,Patients presenting for cataract surgery who were randomly assigned to receive a Tecnis Z9000 IOL (Pfizer) or a Sensar® OptiEdge AR40e IOL (AMO) in 1 eye were followed for 3 months postoperatively. The patient could elect to have the same type of IOL implanted in the fellow eye. The results of sine-wave grating contrast sensitivity testing under mesopic and photopic conditions were compared interindividually. Conclusions:
Results show the Tecnis IOL with a modified prolate anterior surface may produce better contrast sensitivity than a standard spherical IOL under mesopic and photopic conditions. Because contrast sensitivity testing correlates well with functional vision, a goal of future research should be to evaluate patient performance using functional tests such as driving simulation.
Posted by alireza habibollahi at 11:37 PM
The effect of gatifloxacin and moxifloxacin on corneal wound healing.
CRST May 2004
by Randal Olson
Zymar is preserved with 0.005% benzalkonium chloride (BAK), whereas Vigamox is unpreserved. The presence of BAK in topical ophthalmic medications may concern the clinician because many studies have documented its harmful effect on the ocular surface.Due to the known adverse effects of BAK, it was once widely believed that Zymar would more adversely affect the corneal epithelium than would Vigamox. My colleagues and I decided to test this theory. We were surprised that this was not the case. In fact, corneal transplants treated with Zymar had faster epithelial healing after corneal grafting when compared with eyes treated with Vigamox. Vigamox also produced abnormalities of corneal epithelial tight junctions. Moreover, treatment with Zymar resulted in the return of corneal epithelial permeability to near baseline at day 5 despite the potentially harmful presence of BAK. According to Gao et al,5 Zymar significantly facilitated epithelial wound closure in the initial phase of corneal wound healing, and there was no significant increase or delay in epithelial healing in rabbits treated with Zymar. Conversely, Vigamox significantly delayed epithelial wound healing at the early stage of healing.
Posted by mehdi khanlari at 11:25 PM
Flap thickness accuracy: Comparison of 6 microkeratome models
JCRS MAY 2004
USA, AMO Amadeus, Bausch & Lomb Hansatome®, Moria Carriazo-Barraquer, Moria M2, Nidek MK2000, and Alcon Summit Krumeich-Barraquer. Conclusions: Device labeling did not necessarily represent the mean flap thickness obtained, nor was it uniform or consistent. Thinner corneas were associated with thinner flaps and thicker corneas with thicker flaps. In addition, first cuts were generally associated with thicker flaps when compared to second cuts in bilateral procedures.
Posted by alireza habibollahi at 11:21 PM
Management of lens-iris diaphragm retropulsion syndrome during phacoemulsification
JCRS MAY 2004
Lens–iris diaphragm retropulsion syndrome (LIDRS) occurs more often than recognized during small-incision phacoemulsification. This syndrome requires an infusion of fluid into the anterior chamber and is characterized by posterior displacement of the lens-iris diaphragm, marked deepening of the anterior chamber, posterior iris bowing, pupil dilation, and often significant patient discomfort. Using microendoscopy, we have observed that LIDRS is essentially a reverse pupillary block. We describe a surgical technique to mechanically break the iridocapsular block to restore normal chamber depth, relieve patient discomfort, and allow the surgeon to proceed safely with phacoemulsification
Posted by alireza habibollahi at 11:16 PM
CASE PRESENTATION: Sever DLK
CRST May 2004
A 24-year-old white male presented for a LASIK consultation. His refractive errors were -2.50 -0.50 X 90 OD and -2.00 -0.75 X 85 OS. He eventually underwent uneventful, bilateral LASIK . Slit-lamp examination showed severe (3+) DLK in his right eye. Dense, inflammatory infiltrates extended throughout the entire flap interface, including the visual axis. The inflammation was most severe inferiorly. Slit-lamp examination of his left eye showed mild DLK (1 to 2+) in the inferior, peripheral flap interface. The inflammatory infiltrates did not extend into the visual axis of that eye. After the patient was prepped and draped in a sterile fashion, I washed out the flap interface of his right eye with copious amounts of BSS. I did not perform irrigation of his left eye. The patient received a prescription for prednisone 80 mg p.o. q.d., Pred Forte (Allergan, Inc., Irvine, CA) one drop OU every 30 minutes while awake, QUIXIN (Santen Inc., Napa, CA) one drop OU q.i.d., and TOBRADEX ointment (Alcon Laboratories, Inc., Fort Worth, TX) OU q.h.s. On the second postoperative day, the patient’s UCVA was 20/100 OD and 20/20 OS (Figure 1). Slit-lamp examination showed slight improvement in his left eye but worsening DLK in his right eye. This eye had more inflammatory infiltrates (3 to 4+) throughout the visual axis, increased flap edema and folds, 2+ conjunctival injection, and trace cell and flare in the anterior chamber.
HOW WOULD YOU PROCEED?
1. Would you change or continue the topical medications?
2. Change or continue the oral prednisone?
3. Perform another washout?
4. Use a surgical blade to scrape out the antigenic stimulus under the flap, if you decided to perform another washout?
Posted by mehdi khanlari at 11:03 PM
The thick and thin of LASIK flaps
JCRS MAY 2004
We began using the Amadeus microkeratome (AMO).we performed intraoperative pachymetry Our and others' experience with the Hansatome® microkeratome (Bausch & Lomb Surgical) suggested that the flaps tended to be thinner than the plate designation. Astonishingly, we found that the new device's 180 ?m plate produced flap thicknesses ranging from 198 to 258 ?m and the 160 ?m plate produced flaps as thick as 220 ?m.
How should we respond?
As suggested here before we should consider :
1-measuring flap thickness intraoperatively in all patients. It ensures that one does not ablate too deeply into the posterior stroma, enables the surgeon to determine whether the patient can have retreatment surgery in the future, and educates the surgeon about the performance of the microkeratome.
2-We should reconsider the manner in which microkeratome plates are labeled. A single number clearly is inadequate and inaccurate. Solomon et al. suggest labeling plates with the mean thickness ± 2 SDs so surgeons could at least estimate the range of flap thickness for 95% of cases. Perhaps we should consider something slightly more drastic, which would be to label plates according to published ranges of flap thicknesses. Therefore, the Amadeus 140 ?m plate might henceforth be known as the 80–195 ?m plate. This dispels any illusions that clinicians might have regarding the actual flap thickness in any given eye.
Posted by alireza habibollahi at 10:37 PM
IOL Selection for the Weakened Capsular Bag
CRST May 2004
BY DAVID F. CHANG, MD
Because hydrophobic acrylic IOLs are associated with less anterior capsular fibrosis when compared with silicone lenses I believe that the former material is preferable for PXF eyes. Three-piece lens designs with broad, stiff PMMA haptics are able to exert the maximum centrifugal tension against the capsular fornices. They are preferable to the soft, floppy single-piece haptics for this reason. At the most recent AAO Annual Meeting, Da Reitz Pereira et al10 reported on a large ret-rospective study comparing the single-piece and threepiece AcrySof IOLs (Alcon Laboratories, Inc., Fort Worth, TX). With a single surgeon and identical capsulorhexis sizing, the single-piece AcrySof group demonstrated a significantly higher incidence of capsular contraction syndrome. Three percent of the single-piece AcrySof group required a YAG anterior capsulotomy for this condition versus none of the three-piece group. One should probably avoid silicone plate haptic IOLs in PXF eyes, because of these lenses’ haptic design and higher tendency for anterior capsular fibrosis.Finally, one should specifically examine the anterior capsular reaction at the final 1-month postoperative visit in patients with PXF. If there already are signs of early contracture and fibrosis, prophylactic YAG relaxing cuts in the capsulorhexis edge should be considered.Finally, one could place the IOL in the sulcus (Figure 2). The sulcus diameter can be estimated by adding 1.5 mm to the white-to-white horizontal corneal diameter. Thus, the typical foldable IOL of 13 mm in overall length is too short for a corneal diameter of 12 mm or greater. STAAR Surgical Company (Monrovia, CA) makes a 13.5-mm foldable silicone IOL (model AQ 2010 V) that is my preference for sulcus placement. The single-piece AcrySof is not only too short for sulcus placement, but it has thicker, sharpedged haptics that can cause pigment dispersion. If sulcus placement is elected because of a severe zonular dialysis, one should consider making multiple relaxing cuts the capsulorhexis edge to avoid extensive and asymmetric bag contracture with avulsion of the remaining hemisphere of weak zonules.
Posted by mehdi khanlari at 09:35 PM
Botox: beyond wrinkles
Clinics in Dermatology ,January-February ,2004
First used and approved over a decade ago for the treatment of strabismus (or misaligned eyes), botulinum toxin (BTX) has demonstrated efficacy in blepharospasm, hemifacial spasm, spastic lower eyelid entropion, and a number of other disorders seen in the traditional medical environment that are characterized by abnormal muscle contraction. Moreover, other conditions—notably some pain and gastrointestinal disorders—have responded to BTX injections.
Although the modes of action at work in these conditions are not understood completely, there is no doubt that some may have underestimated the therapeutic power of what was once considered the most dangerous substance known to man. It has become clear that the toxin's full therapeutic potential has not yet been realized. This article briefly reviews the areas in which the commercially available toxins—BTX type A (BTX-A; BOTOX®, Dysport®) and type B (BTX-B; MyoBloc™)—have established efficacy and explores preliminary reports of therapeutic promise. Read more...
Posted by afarahi at 12:27 PM
Botulinum neurotoxin for the treatment of migraine and other primary headache disorders
Clinics in Dermatology, January-February,2004
Botulinum toxin A (BoNT/A), a neurotoxin, is effective for treating a variety of disorders of involuntary muscle contraction, including cervical dystonia, blepharospasm and hemifacial spasm. It inhibits neurouscular signaling by blocking the release of acetylcholine at the neuromuscular junction. The biological effects of the toxin are transient with normal neuronal signaling returning within approximately 3-6 months post injection. Recently, clinical findings suggest that BoNT/A may inhibit pain associated with migraine and other headache types. The mechanism by which this toxin inhibits pain is under investigation, recent findings suggest that it inhibits the release of neurotransmitters from nociceptive nerve terminals and in this way may exert an analgesic effect. A number of retrospective open-label chart reviews and three placebo-controlled double-blind trials have demonstrated that localized injections of BTX-A significantly reduce migraine frequency, severity, and migraine-associated disability. The majority of patients in these studies experienced no BoNT/A mediated side effects; however, a small percentage of patients did report transient minor side effects including blepharoptosis, dipolpia, and injection-site weakness. Currently there are several large-scale randomized, placebo-controlled clinical trials in progress evaluating the efficacy, optimal dosing and side effect profile of this toxin as a novel treatment for migraine and other headache types. These studies may provide further evidence that BoNT/A is an effective option for the preventive treatment of migraine.
Posted by afarahi at 12:24 PM
May 28, 2004
Painless acanthamoeba keratitis:A case report
Optometry 2004
One of the hallmarks of keratitis caused by acanthamoeba is
the severe pain associated with the condition, which may be
out of proportion to the apparent degree of corneal
involvement. The case of acanthamoeba keratitis described
here is atypical, in that the patient never complained of any pain.
Although a couple of case reports do exist in the literature1,2,
research suggests that this is the first reported case of painless
acanthamoeba keratitis in the UK.
Posted by mmiraftab at 03:11 PM
Infracyanine-assisted internal limiting membrane peeling in macular hole repair: Does it make a difference?
Graefeaposs Archive for Clinical and Experimental Ophthalmology Vol: 242, Issue: 5, May, 2004
Conclusion. Anatomical and functional results are similar with or without Infracyanine-assisted ILM peeling. There was no apparent adverse effect of Infracyanine use on visual function, and no apparent retinal toxicity was found.
Posted by mmiraftab at 02:50 PM
Eye Warmer
Eyeworld May 2004
For some time, practitioners have advised patients to apply hot compresses for some types of dry eye. A unique ophthalmic disposable heating device known as the Eye Warmer (Kao Corp., Tokyo) has built on this idea. New study results now illustrate the effectiveness of this method in cases of meibomian gland dysfunction (MGD)The disposable device, which is shaped like an eye mask, heats up after it is removed from the package and is applied to a patient’s closed lids. It works very simply.“Through the meibomian gland, it melts the solid oil and provides an oily layer to the ocular surface like a hot compress,”. “It also provides moisture.”The device is currently in the first stage of the Food and Drug Administration approval process.
Posted by mehdi khanlari at 10:57 AM
Alrex
Ophthalmology Management May 2004
A retrospective review of data from 397 patients who used loteprednol etabonate ophthalmic suspension 0.2% (Alrex, Bausch & Lomb) long-term for treatment of seasonal allergic conjunctivitis (SAC) showed that use of the drug caused no adverse effects. Of the 397 patients, 159 used the product for periods ranging from 1 to 4 years, in some cases as often as four times a day. In this subgroup there were no reported incidences of elevated IOP, cataract development or infections.Alrex is the first topical corticosteroid approved by the FDA to treat the signs and symptoms of SAC.
Posted by mehdi khanlari at 10:28 AM
One practitioner’s approach to vanquishing dry eye
Eyeworld My 2004
To forestall LASIK-related dry eye, there are numerous tactics practitioners can take, . Pre-operatively for aqueous deficiency, Donnenfeld starts with a transiently preserved tear, such as Refresh (Allergan, Irvine, Calif.), TheraTears (Advanced Vision Research, Woburn, Mass.), or GenTeal (Novartis, Basel, Switzerland) four times a day. Donnenfeld’s second line therapy is to use Restasis (Allergan) twice a day.“I like to give Restasis for one month prior to surgery,”If the patient has improved he will then perform the LASIK procedure. However, if the patient has not gotten sufficient relief, Donnenfeld then adds punctal plugs to the mix.In performing the LASIK procedure itself, Donnenfeld tries to make the hinge as wide as possible.He also makes the flap as small as possible. To minimize ocular surface toxicity, he uses minimal medications, starting the anesthetic immediately prior to surgery. “I use a mild fluoroquinolone antibiotic and immediately post-operatively, 30 seconds after the procedure, will apply Refresh Liquigel (Allergan) to stabilize the ocular surface,” . Also for the first four hours following surgery, keep their eyes closed to allow the eyes to heal. Post-operatively, Donnenfeld recommends Refresh Liquigel or TheraTears Liquid Gel every two hours for the first day.After that, use a transiently preserved tear at least four times a day for the first week after surgery. If patients show signs of dry eye in the post-operative period, put in punctal plugs to stabilize the ocular surface.If the patients continue to have irritation after surgery then I go to Restasis after plugs,
Posted by mehdi khanlari at 09:03 AM
May 26, 2004
Environmental factors and IOL opacification
Eyeworld May 2004
Based on a laboratory analysis using gas chromatography and mass spectrometry, the manufacturer of the lenses determined the cloudiness was related to IOL changes caused by molecules called terpenes and ketones .Intraocular lenses can absorb aerosolized chemicals inside their unopened packages,” . “These chemicals are capable of producing unexpected changes in IOLs that may impact how the lenses behave when exposed to the aqueous environment of the eye Silicone lenses are normally hydrophobic, with a water content of less than 1%, . A change in the surface characteristics could lead to a lens that is relatively more hydrophilic. Influx of aqueous within the lens would then lead to cloudiness.Although calcium deposits have been described in the past few years as a cause for whitish lens opacification, that was certainly not the cause of lens cloudiness for these IOLs, Werner said.“If the medical facility in question needs to be sprayed with aerosolized disinfectants, insecticides, cleaning solutions, or other volatile chemicals, IOL packages should be removed from the area while this is done, as sprays may be inadvertently introducing chemicals through the package and onto the lenses,”All IOLs also should be stored in a dry environment and at room temperature, Werner said.
Posted by mehdi khanlari at 05:01 PM
IOL protection rating
Eyeworld May 2004
The retinal protection factor (RPF), developed by Gary Hall, M.D., of Phoenix, Ariz., rates IOLs for their solar protective value in terms of retinal protection from UV and blue light.The RPF rating system is a derivative of another system Hall developed over the last 10 years to rank the solar eye protection factor (EPF) of sunglasses. The RPF was based on the same data Hall collected for the EPF system, with some modifications.Intraocular lenses are easier to rate than sunglasses, because they only potentially shield the retina as opposed to the entire eye. Hall’s analysis found three of the five lenses tested allowed some transmittance of highly toxic UV radiation to the retina: The AMO AR40e and Phacoflex II SI40NB (Advanced Medical Optics, Santa Ana, Calif.) and the AcrySof MA60BM (Alcon, Fort Worth, Texas).The CeeOn 911A (Pfizer Ophthalmics, New York, N.Y.) and Alcon’s AcrySof Natural blocked 100% of UV light. The other component of the overall RPF was an analysis of the blue light that the lens transmitted. Hall found the blue light factor ranged from the worst for the AMO AR40e and the best performance by the AcrySof Natural.. The significance of the blue light rating was based upon further calculations and deduction. Acceptance of the danger from UV is at least partially based on the understanding that the retina is about five times as sensitive to UV over the entire spectrum of UVA than it is to blue light over the entire spectrum.However, because only 1.3% of UV transmits to the retina, while 60% of blue transmits to the retina, and there is about twice as much blue in the earth’s environment as there is UV, therefore, blue light is more toxic to the retina than UV.But Mainster had problems with Hall’s IOL rating system for several reasons....
Posted by mehdi khanlari at 04:31 PM
AcrySof Natural and SWAP
Eyeworld May 2004
.....The AcrySof Natural’s product insert cautions deliberation before implanting it in patients with glaucoma or clinically significant macular or RPE changes. It’s a poor choice for people that have or might get AMD because AMD patients have worse scotopic vision than people of the same age without AMD. The AcrySof Natural IOL blocks 54% of 440 nm light, so it’s probably also a poor choice for glaucoma patients because short wavelength automated perimetry (SWAP) uses a blue 440-nm stimulus. If SWAP perimetry can be performed effectively after AcrySof Natural implantation, results will probably be abnormal.....
Posted by mehdi khanlari at 03:48 PM
Contraindications for LASIK no problem for PRK!!!
Eyeworld may 2004
Keratoconus — both latent and manifest — previous RK, and thin corneas are contraindications for LASIK surgery, but they are not for PRK, said S. Percy Amoils,FRCS, Johannesburg Excimer Laser Centre, Johannesburg, South Africa
“There’s no question — you can treat latent and frank keratoconus with PRK!!!.” . “Because you don’t cut Bowman’s membrane, you can get good results.”No progress of ectasia nine years after PRK with 20/25 uncorrected vision . Amoils warned that larger LASIK treatment zones also could lead to an increase in corneal ectasia in coming years.!!!PRK for previous RK patientsIn yet another study, Amoils said he and colleagues treated 54 eyes with PRK after RK and also obtained good results.Amoils can’t yet tell which helped achieve better results — topical or intra-operative mitomycine— but said intra-operative is faster.“Intra-operatively is easier because you just use a little pledget on the cornea for 90 seconds,” Amoils said. “With topical application, you have to use a drop twice a day for two to six weeks.!!!”Amoils said he is switching to intra-operative mitomycin C use was a little worried about intra-operative mitomycin C with post-RK patients because of the old radial cuts, and I was worried that the drug might penetrate through the cuts, “But today, I am now using it intra-operatively on all my RK cases.!!!!”PRK also is better than LASIK for high myopia cases, Amoils said. While many surgeons do not perform LASIK on eyes with more than 10 D of myopia, Amoils said he routinely performs PRK on eyes with up to 15 D!!!.In a study Amoils performed on 64 eyes with myopia ranging from 8 D to 17 D, 100% achieved 20/40 or better UCVA, 82% achieved 20/30 or better and 70% achieved 20/25 or better. The eyes were treated with intra-operative mitomycin C.
Posted by mehdi khanlari at 12:39 PM
The bottom line on when to use SWAP
Eyeworld May 2004
Use of short-wavelength automated perimetry (SWAP) in glaucoma patients is currently recommended in secondary and tertiary care settings.It’s best for evaluating patients that are ocular hypertensives, that are glaucoma suspects, and that have early to moderate glaucoma. “It can definitely assist practitioners in deciding which patients are at highest risk for converting to glaucoma or which glaucoma patients are most likely to progress Additionally it is more sensitive than standard automated perimetry in several other diseases besides glaucoma, such as diabetes, optic neuritis, HIV-related vision loss, and migraines but patients with cataracts can have an abnormal SWAP test, because cataracts can affect patients’ ability to separate yellow and blue.“The yellowing in the lens will reduce the sensitivity to the target. Another disadvantage of SWAP is that it has more variable responses, both between individuals and within an individual. Swedish Interactive Testing Algorithm (SITA) SWAP,(SITA-SWAP) which is expected to be available sometime this year, has a much better normative database. In addition, it should have some reduced inter-individual variability because regular SITA does that for standard fields,”“The bottom line is to wait for SITA-SWAP, but once that’s available, if it works the way we think it does, this should be an excellent test for practice,” she said.
Posted by mehdi khanlari at 12:18 PM
May 25, 2004
Prospective, Randomized, Paired Comparison of Laser Epithelial Keratomileusis and Photorefractive Keratectomy for Myopia Less Than -6.50 Diopters
Journal of Refractive Surgery Vol. 20 No. 3 May/June 2004
Hassan Hashemi, MD; Akbar Fotouhi, MD, MPH; Hamid Foudazi, MD; Navid Sadeghi, MD; Saeed Payvar, MD
PURPOSE
We compared predictability, efficacy, safety, and patient satisfaction following laser epithelial keratomileusis (LASEK) and photorefractive keratectomy (PRK) for low to moderate myopia with either the Nidek EC-5000 excimer laser or the Technolas 217C excimer laser.
METHODS
Forty-two patients with spherical equivalent refraction in the range -1.00 to -6.50 D were enrolled in this prospective study, each randomized for choice and sequence of LASEK and PRK on each of their eyes. Patients were examined daily for 7 days, and at 1 and 3 months. Patient satisfaction and quality of vision were assessed using a subjective questionnaire.
RESULTS
Mean baseline refraction was -3.57 ± 1.25 D in LASEK eyes and -3.44 ± 1.13 D in PRK eyes. Follow-up rates were 100% up to 1 month and 76% at 3 months. At 3 months, 32 (100%) of LASEK eyes and 31 (97%) of PRK eyes had uncorrected visual acuity >20/40, 25 (79%) of LASEK eyes and 26 (82%) of PRK eyes had uncorrected visual acuity >20/20, mean refraction was 0.08 ± 0.53 D in LASEK eyes and 0.12 ± 0.50 D in PRK eyes, 26 (81%) of LASEK eyes and 23 (72%) of PRK eyes had a refraction within ±0.50 D and 29 (91%) of LASEK eyes and 30 (94%) of PRK eyes had refraction within ±1.00 D. Epithelial healing time and pain in LASEK and PRK eyes were not statistically different, and patients were equally satisfied.
CONCLUSION
LASEK had similar predictability, efficacy, safety, and patient satisfaction to PRK in the treatment of low to moderate myopia.
Posted by mmiraftab at 06:54 PM
What’s next for IOLs:Toric (Alcon, Fort Worth, Texas)
EyeWorld May 2004
Koch: I was one of the implanting surgeons in this clinical trial. This lens is incredible. In our experience with around 20 lenses, none have rotated more than 5 or at most 10 degrees, and this may just be measurement variability. It gives a wonderful correction of the astigmatism. I’ve spent years refining relaxing incisions, and when this lens is approved, I’m going to lay down the diamond knife.
Posted by mmiraftab at 06:47 PM
Total and Corneal Optical Aberrations Induced by Laser in situ Keratomileusis for Hyperopia
Journal of Refractive Surgery Vol. 20 No. 3 May/June 2004
Total and corneal aberrations were measured before and after standard hyperopic LASIK in 13 eyes (preoperative spherical equivalent refractive error +3.17 ± 1.10 D). The Chiron Technolas 217C laser with PlanoScan was used. Total aberrations (measured using laser ray tracing) and corneal aberrations (estimated from a videokeratoscope) were described using Zernike terms. Root-mean-square wavefront error for both total and corneal aberrations, and through-focus Strehl ratio for the point spread function of the whole eye were used to assess optical changes induced by surgery.
RESULTS
Third and higher order aberrations increased significantly after hyperopic LASIK (by a factor of 2.20 for total and 1.78 for corneal aberrations, for a 6.5-mm pupil). Spherical aberration changed to negative values (corneal average decreased by -0.85 ± 0.48 µm and total average by 0.70 ± 0.30 µm). Best Strehl ratio for the whole eye decreased by a factor of 1.84. Hyperopic LASIK induced larger changes than myopic LASIK, compared to an equivalent group of myopic eyes from a previous study. Induced corneal spherical aberration was six times larger after hyperopic LASIK, for similar range of correction, and of opposite sign. As with myopic LASIK, changes in internal spherical aberration are of opposite sign to those induced on the corneal anterior surface.
CONCLUSIONS
Hyperopic LASIK induced significant amounts of aberrations. The largest increase occurred in spherical aberration, which showed a shift (toward negative values) of opposite sign; increase was greater than for myopic LASIK.
Posted by mmiraftab at 06:30 PM
CATARACT SURGERY: Managing Weak Zonules
OPHTHALMOLOGY MANAGEMENT April 2004
...Removing a Standard CTR
Dr. Gimbel notes that some surgeons are nervous about removing a CTR because it's out of sight inside the bag. "If a problem such as a torn capsulorhexis rim occurs after a CTR has been inserted," he says, "reach in with a Sinskey hook and grab any part of the ring and pull it into view so you can hook the eyelet with another Sinskey hook or grasp it with a forceps."You may risk tearing the capsule further, but you're already dealing with a torn capsule; it's unlikely that a Sinskey hook will cause more damage."
The Anterior Chamber Lens Option
Richard Mackool, M.D., director of The Mackool Eye Institute and Laser Center in Astoria, N.Y., and senior attending surgeon at the New York Eye and Ear Infirmary, notes that being able to put an IOL in the bag with the endocapsular ring doesn't mean you always should."When you know that a weak zonule could lead to eventual dislocation of the capsular bag and its IOL," he says, "consider placing an endocapsular ring in the bag to establish a (hopefully) permanent position for the capsule -- but implant an anterior chamber lens instead of placing the IOL in the bag or sulcus. The capsule will separate the anterior and posterior segments, reducing the likelihood of macular edema and vitreoretinal complications; meanwhile, the anterior chamber lens will remain perfectly fixated."
Posted by mmiraftab at 06:08 PM
Cataract Surgeon Perspectives on the Acrysof Natural IOL
OPHTHALMOLOGY MANAGEMENT April 2004
The AcrySof Natural IOL has been on the market internationally since September 2002. After more than 300,000 implants, there are no confirmed scotopic or color perception issues. Any claims that suggest patients implanted with the AcrySof Natural IOL will have abnormal color perception or decreased night driving vision are theoretic at best. The FDA study data, the recently completed FM-100 Hue study, and the extensive clinical experience we have with this IOL clearly demonstrate that there are no negative visual consequences to using the AcrySof Natural IOL.AMD is one of the leading causes of blindness in the developed world 25. Although there are additional risk factors for AMD, increased exposure to blue light following the removal of a cataract is one factor that can now be addressed. My patients are thrilled that I can provide them with more natural vision and increased retinal protection without any negative visual consequences following cataract surgery.(By Dr. Cionni is medical director of the Cincinnati Eye Institute. He's also a consultant to Alcon.)
Without conclusive data and a complete understanding of all of the complex interacting factors affecting the optics and sensory components of the visual system, blocking or filtering visible blue light is inappropriate. Reproducing the properties of the 20-year-old crystalline lens is appropriate and takes into account 150,000 years of development in our environment. This has been proven true with regard to spherical aberration, where designing an IOL to match the negative spherical aberration of the 20-year-old crystalline lens significantly improves retinal image contrast, contrast sensitivity, and night driving performance .The idea of replicating the 50-year-old lens because this is a "protective" phenomenon of the eye with age, as opposed to a simple aging process, is no different than suggesting 50-year-old skin damaged from UV is ideal and is protective against further UV damage. Re-creating the optical performance of the 20-year-old crystalline lens with regard to monochromatic and chromatic performance should be our goal until our knowledge and our ability to "improve" the system significantly increases.(By Dr. Holladay is a clinical professor of ophthalmology at Baylor College of Medicine in Houston. He is also a consultant to Pfizer and Advanced Medical Optics, Inc.)
Posted by mmiraftab at 05:43 PM
The prevalence and causes of visual impairment in Tehran: the Tehran Eye Study
British Journal of Ophthalmology 2004;88:740-745
A Fotouhi, H Hashemi, K Mohammad and K H Jalali
Aims: To determine the prevalence and causes of visual impairment in Tehran, Iran, through a population based study.
Methods: In a population based, cross sectional study, 6497 Tehran citizens were sampled from 160 clusters using a stratified, random, cluster sampling strategy. The eligible people were enumerated through a door to door household survey in the selected clusters and were invited. All participants were transferred to a clinic for an extensive eye examination and interview. Visual impairment was determined using presenting and best corrected visual acuity (low vision: visual acuity of less than 6/18 to 3/60 in the better eye; blindness: visual acuity of less than 3/60 in the better eye).
Results: Of those sampled, 4565 (70.3%) people participated in the study. The age and sex standardised prevalences of visual impairment on the basis of best corrected and presenting visual acuity were 1.39% (95% confidence interval (CI), 1.07 to 1.71) and 2.52% (95% CI, 2.07 to 2.97), respectively. 15 people (0.28%; 95% CI, 0.14 to 0.42) were blind with corrected vision while 22 (0.39%; 95% CI, 0.23 to 0.56) were blind with presenting vision. Using the corrected and presenting vision, the prevalence of low visual impairment was 1.11% (95% CI, 0.84 to 1.39) and 2.13% (95% CI, 1.71 to 2.55), respectively. The causes of visual impairment according to the best corrected vision were cataract (36.0%), macular degeneration (20.0%), and amblyopia (10.7%). However, according to the presenting vision, uncorrected refractive errors were the most frequent primary cause (33.6%) and cataract (25.4%), macular degeneration (12.7%), and amblyopia (8.2%) were the other main causes of visual impairment in the study sample. The prevalence of visual impairment was associated with advancing age and lower education.
Conclusion: The results indicate that the burden of visual impairment is important and, although easily preventable, uncorrected refractive errors and cataract have a major role as causes of visual impairment in this population. Results also highlight the need for visual impairment prevention programmes, with emphasis on treatment of refractive errors and cataract.
Posted by mmiraftab at 12:35 AM
Single versus three piece acrylic IOLs
British Journal of Ophthalmology 2004;88:727-728
In 2000, Alcon introduced a significantly different design—the single piece AcrySof. Having moulded and floppier haptics permits this IOL to be more easily injected through a small incision. Reduced wound size is particularly important for clear corneal cataract incisions. While the square edge design was maintained, modifications to reduce the aforementioned dysphotopsias were incorporated. The single piece models featured a frosted edge and a steeper anterior curvature—changes that have since been made to the three piece AcrySof models as well. In the brief ensuing period, the single piece AcrySof has become the most popular foldable IOL in the United States, where it accounts for 80% of total AcrySof sales. In Europe, 50% of Alcon’s AcrySof sales are the one piece models.
Posted by mmiraftab at 12:30 AM
May 23, 2004
Lipid link to diabetic retinopathy
Invest Ophthalmol Vis Sci 2004;45:910-18.
New data gleaned from the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications Study (DCCT/EDIC) suggests that there is a link between lipid profiles of patients with Type I diabetes and retinopathy status. US researchers report that the severity of retinopathy was positively associated with triglycerides and was negatively associated with high-density lipoprotein cholesterol in both men and women. Retinopathy was positively associated with small and medium very low-density lipoprotein and negatively with VLDL size. Retinopathy was positively associated with small LDL, LDL particle concentration, apoB concentration and small HDL among male patients.The study revealed no link between retinopathy and apoA1, Lp(a), or susceptibility of LDL to oxidation.
Posted by mehdi khanlari at 07:08 PM
Three phakic IOLs compared
Eurotimes April 2004
Spanish researchers evaluated three different phakic IOLs, the Adatomed, Staar, and Artisan in patients with high myopia in a prospective study of 217 eyes of 118 patients. The mean preoperative spherical equivalent ranged from –15.39 D to –16.17 D among the three treatment groups.All groups showed improvements in best-corrected and uncorrected visual acuities, with no statistically significant difference in favour of any one lens.The effects on IOP and pigment deposition were also similar in all three groups. The researchers noted a significantly higher level of anterior cataract formation in the Adatomed group.The development of nuclear cataract in two Artisan recipients also suggests that age and axial length may be important prognostic factors.
Posted by mehdi khanlari at 07:04 PM
Corneal collagen cross-linking
Eurotimes April 2004
CORNEAL collagen cross-linking procedure involving the topical application of riboflavin followed by ultraviolet irradiation appears to be effective in arresting the progression of keratoconus, according to Theo Seiler MD, PhD. Initial clinical experience in a series of 26 eyes of 25 patients with moderate to advanced keratoconus followed for a minimum of one year showed that the cross-linking procedure halted the progression of keratoconus, improved visual function in some eyes, and caused no adverse effects.They first underwent abrasion of the central cornea to improve penetration of the riboflavin, which was applied as a 0.1% solution. After a short waiting period of five minutes, the cornea was exposed to 365 nm UVA light for 30 minutes.However, we considered endothelial cell density a critical safety parameter since the endothelium is the closest structure sensitive to potential adverse effects of UV irradiation,"
Posted by mehdi khanlari at 06:55 PM
AcrySof phakic IOL
OSN May 2004
An anterior chamber phakic IOL made of a hydrophobic acrylic material is providing good vision to patients in a European clinical trial. The lens, a phakic version of the Alcon AcrySof, has up to 3-year follow-up in the open-label multicenter European study, according to Joseph Colin, MD.The AcrySof phakic IOL is an anterior chamber angle-supported lens with a 5-mm-diameter meniscus optic and flexible haptics with four-point fixation, he said. To date, 102 of the lenses have been implanted unilaterally in patients with stable high myopia and up to 2 D of astigmatism.At 6 months, 100% of eyes achieved 20/20 or better vision with correction, Regarding refraction, at 6 months 95% of eyes are within 1 D of target, and 67% are within 0.5 D, Dr. Colin said. Mean cell loss of 2.9% was reported in the study eyes, he added.Dr. Colin said results with the AcrySof phakic IOL to date exceed Food and Drug Administration guidelines for phakic IOLs Dr. Colin said the white-to-white distance is the basis for the choice of size, but the sizing is not as crucial with the flexible haptics of the AcrySof lens as with more rigid angle-supported IOLs.
Posted by mehdi khanlari at 06:29 AM
Spontaneous disinsertion of a multipiece foldable acrylic intraocular lens haptic 3 and 12 months after implantation
JCRS May 2004
We report 2 cases of spontaneous postoperative haptic disinsertion with the Alcon AcrySof® MA60BM PC IOL. A 14-year-old girl with a history of acute retinal necrosis and pars plana vitrectomy with lensectomy for retinal detachment repair had secondary implantation of a PC IOL in the ciliary sulcus. Three months later, the superior haptic disinserted from the optic and dislocated into the anterior chamber. In the second case, a 22-year-old man had lens aspiration and PC IOL implantation in the capsular bag. One year after surgery, the PC IOL had a similar problem, with the disinserted superior haptic remaining in the capsular bag while the optic and inferior haptic dislocated into the anterior chamber. In both patients, the PC IOLs were exchanged for rigid single-piece PC IOLs. The patients have had no further problems.
Posted by alireza habibollahi at 12:04 AM
May 22, 2004
Refractive lensectomy and cross-cylinder LASIK for the correction of extreme hyperopic astigmatism
JCRS May 2004
Bilateral Refractive lensectomy followed by cross-cylinder LASIK was performed in a 46-year-old patient with extreme hyperopic astigmatism. Six months postoperatively, the uncorrected visual acuity was 20/25 with a manifest refraction of +0.25 ?0.50 × 44 in the right eye and +0.25 ?0.25 × 10 in the left eye. The best corrected visual acuity remained unchanged in both eyes at 20/25. Refractive lensectomy and cross-cylinder LASIK can be effective for treating extreme hyperopic astigmatism.
Posted by alireza habibollahi at 11:57 PM
Long-term observation of the refraction with a reversed-optic PCIOL.
JCRS May 2004
A 73-year-old man hadbilateral phaco-IOL.In OD the optic was unintentionally reversed in the bag. In OS the posterior capsule was ruptured and the IOL haptics were fixated in the ciliary sulcus. The refraction in the sulcus-fixated was stable from 1 month to 4 years. 'but in other eye a myopic shift at 1 month, with a regression of 1.50 diopters that continued for 2 years. The final IOL position in the right eye was 0.25 mm anterior to the position predicted by the SRK/T formula. It took 2 years for the refraction in the eye with the reversed-optic PC IOL to become stable. A large myopic shift and gradual regression in refraction may stem from a different wound-healing reaction than that of properly fixated IOLs.
Posted by alireza habibollahi at 11:46 PM
Capsular block syndrome caused by a reversed-optic intraocular lens
JCRS May 2004
A 52-year-old man who had phacoemulsification and in-the-bag fixation of a posterior chamber intraocular lens (IOL) developed capsular block syndrome 1 day after reverse implantation of the IOL. After a neodymium:YAG (Nd:YAG) laser peripheral anterior capsulotomy, the distended capsular bag collapsed significantly and the artificial myopia partially resolved. An Nd:YAG laser peripheral anterior capsulotomy appeared to be an effective, simple, and minimally invasive method to treat this problem.
Posted by alireza habibollahi at 11:42 PM
Correction of spherical myopia with a single 150-degree Intacs
JCRS May 2004
A 47-year-old woman with an UCVA of 20/70 and a refraction of ?1.50 +0.75 × 75 in the right eye had 2 0.25 mm Intacs® inserted uneventfully through a superior incision. The patient was hyperopic 2 years later with a refraction of +0.50 +0.75 × 25 and was intolerant of spectacles. She also complained of temporal glare. Twenty-seven months after insertion, the temporal ring segment was removed. Four months later, the UCVA was 20/20; with a refraction of plano +0.50 × 35, the visual acuity was 20/15. Topography showed corresponding regular astigmatism, and the patient's glare had resolved. Removal of 1 Intacs segment may be an option in cases of overcorrection after ring insertion for myopia.
Posted by alireza habibollahi at 11:34 PM
Dietary fat consumption and primary open-angle glaucoma
American Journal of Clinical Nutrition May 2004
Prostaglandin F2 analogues are effective intraocular-pressure-lowering drugs. Dietary fatty acids affect endogenous prostaglandin F2 concentrations and may thus influence intraocular pressure.We found a suggestive positive association between a higher ratio of n–3 to n–6 polyunsaturated fat and risk of POAG [RR = 1.49 (1.11, 2.01A high ratio of n–3 to n–6 polyunsaturated fat appears to increase the risk of POAG, particularly high-tension POAG.
Posted by mehdi khanlari at 11:29 PM
Late corneal scarring after retinal detachment surgery 42 months after PRK.
JCRS May 2004,
A 42-year-old man had uneventful bilateral nonsimultaneous PRK for severe myopia. Thirty-nine months after the procedure, the patient presented with a retinal detachment (RD) in the right eye. Cerclage, vitrectomy, endolaser, and intravitreal silicone oil tamponade were performed, and the RD was successfully repaired. Three months after vitrectomy and 42 months after PRK, the patient complained of visual impairment in the right eye and photophobia. On slitlamp examination, marked reticular scarring of the central anterior cornea was observed. The occurrence of late-onset corneal haze highlights the need for special attention to patients who have vitrectomy after PRK.
Posted by alireza habibollahi at 11:25 PM
test
Posted by alireza habibollahi at 11:23 PM
May 21, 2004
The prevalence and causes of visual impairment in Tehran: the Tehran Eye Study
A Fotouhi1, H Hashemi2,3, K Mohammad1 and K H Jalali3
BJO,June,2004
In a population based, cross sectional study, 6497 Tehran citizens were sampled from 160 clusters using a stratified, random, cluster sampling strategy. The eligible people were enumerated through a door to door household survey in the selected clusters and were invited. All participants were transferred to a clinic for an extensive eye examination and interview. Visual impairment was determined using presenting and best corrected visual acuity (low vision: visual acuity of less than 6/18 to 3/60 in the better eye; blindness: visual acuity of less than 3/60 in the better eye).
Of those sampled, 4565 (70.3%) people participated in the study. The age and sex standardised prevalences of visual impairment on the basis of best corrected and presenting visual acuity were 1.39% (95% confidence interval (CI), 1.07 to 1.71) and 2.52% (95% CI, 2.07 to 2.97), respectively. 15 people (0.28%; 95% CI, 0.14 to 0.42) were blind with corrected vision while 22 (0.39%; 95% CI, 0.23 to 0.56) were blind with presenting vision. Using the corrected and presenting vision, the prevalence of low visual impairment was 1.11% (95% CI, 0.84 to 1.39) and 2.13% (95% CI, 1.71 to 2.55), respectively. The causes of visual impairment according to the best corrected vision were cataract (36.0%), macular degeneration (20.0%), and amblyopia (10.7%). However, according to the presenting vision, uncorrected refractive errors were the most frequent primary cause (33.6%) and cataract (25.4%), macular degeneration (12.7%), and amblyopia (8.2%) were the other main causes of visual impairment in the study sample. The prevalence of visual impairment was associated with advancing age and lower education.
Conclusion: The results indicate that the burden of visual impairment is important and, although easily preventable, uncorrected refractive errors and cataract have a major role as causes of visual impairment in this population. Results also highlight the need for visual impairment prevention programmes, with emphasis on treatment of refractive errors and cataract.
Posted by afarahi at 07:31 PM
Internuclear ophthalmoplegia as an isolated or predominant symptom of brainstem infarction
Neurology,May,2004
Isolated or predominant INO is a unique clinical stroke syndrome caused by small dorsal brainstem infarction. The pathogenesis, however, is heterogeneous, including distal occlusion of small penetrating arteries, atheromatous branch occlusion from the BA, SCA, or PCA, or major BA occlusion. The functional prognosis of these patients is excellent, although the INO tends to last longer when there are other neurologic deficits.
Posted by afarahi at 07:08 PM
Continuous curvilinear capsulorhexis with use of an endoscope
JCRS,May,2004
Authors describe a technique for creating a continuous curvilinear capsulorhexis (CCC) using an endoscope. Three 2.0 mm limbal incisions 120 degrees apart were made in 4 cadaver eyes. The anterior capsule was stained with trypan blue 0.1% (Vision Blue®). Under endoscopic visualization, a CCC was attempted in each of the 4 globes. It was completed in 1 of them. Endoscopy provides a safe and effective tool to visualize the anterior chamber and perform a CCC when there is a poor view through the cornea.
Posted by afarahi at 07:03 PM
May 19, 2004
Treatment of Xanthelasma Palpebrarum with Argon Laser Photocoagulation
International OphthalmologyJanuary 2004
We report the results of argon laser coagulation of xanthelasma lesions. Methods: Forty eyelids of 24 patients with xanthelasma were treated in 1 to 4 sessions at 2–3 week intervals, using an argon green laser. The laser parameters were as follows: wavelength 514 nm; spot size 500 microns; energy 900 mW; the duration of the laser pulse 0.1–0.2 seconds. The procedure was done on outpatient basis. A gauze pad soaked in topical anaesthetic eye drops was applied to the surface of the lesion. Results: The therapy was well tolerated, and all lesions responded to the therapy. There were no complications and no functionally relevant scar developed. The cosmetic outcome was considered to be good in 85% of the cases. Conclusion: Argon laser photocoagulation represents an alternative treatment in selected cases. It is easy to perform and well tolerated by the patients.
Posted by mehdi khanlari at 07:18 AM
Residual bed thickness and corneal forward shift after laser in situ keratomileusis
JCRS May 2004
Conclusions: Even if a residual corneal bed of 300 ?m or thicker is preserved, anterior bulging of the cornea after LASIK can occur. Eyes with thin corneas and high myopia requiring greater laser ablation are more predisposed to an anterior shift of the cornea.
Posted by mehdi khanlari at 06:54 AM
May 17, 2004
New Treatment for Multiple Sclerosis
Ivanhoe.com
A popular treatment for lowering cholesterol may also benefit patients with multiple sclerosis. New research finds statins reduce the number of brain lesions in patients with MS.Researchers from the Medical University of South Carolina in Charleston conducted a study to see if the cholesterol-lowering drug simvastatin, also called Zocor, would have an effect on the number of brain lesions in MS patients.Recent research suggests satins promote an anti-inflammatory response from the immune system. The study included 30 people with MS who were given simvastatin daily for six months. Patients underwent magnetic resonance imaging (MRI) to measure the number of brain lesions.Patients in the study had a 44-percent reduction in the proportion of brain lesions after three months of treatment compared with lesions identified before treatment began. Researchers say this could be a big step forward, but much more research is needed. Study authors say the next step is randomized controlled clinical trials, which are already being started
Posted by mehdi khanlari at 11:14 PM
Corneal Thickness in Congenital Glaucoma.
Journal of Glaucoma. 13(3):185-188, June 2004.
Central corneal thickness was significantly thinner in children with congenital glaucoma. This finding may be another confounding factor when measuring IOP in those patients. Pachymetry should be considered during their examination
Posted by mehdi khanlari at 11:04 PM
Bone Marrow-Derived Cells Are Present in Mooren's Ulcer
Ophthalmic Research 2004
Bone marrow-derived cells are present in Mooren's ulcer and contribute to its destructive and regeneration process by synergizing with other factors. Specific therapeutic strategies that target the role of these cells in Mooren's ulcer are anticipated.
Posted by mehdi khanlari at 11:00 PM
Sunlight and the 10-Year Incidence of Age-Related MaculopathyArchives of Ophthalmology
Few significant relationships between environmental exposure to light and the 10-year incidence and progression of ARM were found in the Beaver Dam Eye Study. Consistent with results from the baseline and 5-year follow-up examinations, significant associations were found between extended exposure to the summer sun and the 10-year incidence of early ARM and increased retinal pigment. A protective effect of hat and sunglasses use by participants while in their teens and 30s against the 10-year incidence of soft indistinct drusen and retinal pigment epithelial depigmentation was also found, but only in those who reported the highest amount of sun exposure during the same periods
Posted by mehdi khanlari at 10:51 PM
Axial length and age at cataract surgery
Journal of Cataract & Refractive SurgeryMay 2004
Conclusion: An increase in the axial length of the eye was associated with a lower mean age at time of cataract surgery.
Posted by mehdi khanlari at 10:49 PM
Visual axis opacification after AcrySof intraocular lens implantation in children*1
Journal of Cataract & Refractive Surgery May 2004
Conclusions: AcrySof IOL implantation with appropriate management of the posterior capsule maintained a clear visual axis in 60.2% of eyes. Of the 39.8% of eyes with visual axis opacification, 13.6% had visually significant opacification and required a secondary procedure.
Posted by mehdi khanlari at 10:42 PM
Association of Magnetic Resonance Imaging of Anterior Optic Pathway with Glaucomatous Visual Field Damage and Optic Disc Cupping.
Journal of Glaucoma. 13(3):189-195, June 2004.
The optic nerve diameter was significantly smaller in glaucoma patients (2.25 +/- 0.33 mm) than in controls and the height of the optic chiasm was significantly shorter in glaucoma patients than in controls . The optic nerve diameter showed significant correlation with MD score and C/D ratio . These correlations are similar to that between MD score and C/D ratio . Conclusion: Glaucoma affects the anterior visual pathway anterogradely at least up to the optic chiasm, and these morphologic changes in the anterior visual pathway are correlated with glaucomatous optic nerve damage. MRI of the anterior visual pathway may be a good tool for evaluating glaucomatous damage objectively.
Posted by mehdi khanlari at 10:09 PM
May 16, 2004
Ketorolac for the Regression of Myopic LASIK Overcorrection.
Cornea. 23(4):339-344, May 2004.
To determine whether ketorolac (AcularTM) treatment and other factors influence regression after LASIK-induced consecutive hyperopia. Seventy-two eyes of 51 patients who had undergone LASIK for myopia and compound myopic astigmatism and who experienced consecutive hyperopia of at least +0.50 diopters within the first postoperative week were analyzed. The consenting patients were treated with ketorolac (AcularTM). Data were collected over a period of 2 months. Primary preoperative variables included age, eye, preoperative manifest and cycloplegic refractions, and pachymetry. Postoperative variables included presence of microstriae and treatment with ketorolac. Treatment success was measured as reduction of consecutive hyperopia.Conclusions: Ketorolac does not improve consecutive hyperopia after LASIK for myopia and compound myopic astigmatism when compared with a matched control group. Pachymetry appears to be a determining factor in the degree of regression experienced after consecutive hyperopia. This finding warrants further investigation
Posted by mehdi khanlari at 11:08 PM
Mumps-Induced Corneal Endotheliitis.
Cornea. 23(4):400-402, May 2004.
Conclusions: Corneal endotheliitis as a sequela to mumps is a new reported association. Timely treatment with topical steroids led to resolution of the disease with full visual recovery without any residual symptoms or signs
Posted by mehdi khanlari at 10:59 PM
Long term effect of latanoprost on intraocular pressure in normal tension glaucoma
BJO May 2004
Conclusion: Latanoprost had a sustained hypotensive effect in eyes with NTG and 41% of treated patients achieved a reasonable response. However, in the majority of eyes with NTG, latanoprost monotherapy may be insufficient in producing a desirable 30% reduction in IOP.
Posted by mehdi khanlari at 10:47 PM
Biocompatibility of Trypan Blue With Human Corneal Cells Arch Ophthalmol. 2004;122:736-742.
To quantify the toxicity of trypan blue on human corneal cells according to exposure time and concentrationMethods Three in vitro experiments were performed. (1) We exposed cultured human corneal fibroblasts to trypan blue (0.0001% to 0.1%) in Eagle modified minimum essential medium (EMEM) or phosphate-buffered saline (PBS) for 15 minutes to 24 hours. Cytotoxicity was evaluated by Mosmann's colorimetric 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MMT) assay. (2) We exposed human corneas in EMEM for 24 hours to trypan blue (0.001% to 0.1%). Fellow donor corneas served as controls. Endothelial survival was evaluated morphologically and by cell density assessment. (3) We morphologically compared the endothelial viability of human donor corneas after exposure to 0.1% trypan blue for 5 to 30 minutes with control corneas.In experiment 1, trypan blue in EMEM was not significantly toxic at concentrations of 0.005% or lower. Higher concentrations were toxic only after exposure to trypan blue for at least 6 hours. In PBS, significant toxicity was found after exposure to 0.1% trypan blue for 30 minutes or longer. Lower concentrations were toxic after longer exposures. In experiment 2, exposure to 0.01% and 0.1% trypan blue for 24 hours resulted in significant loss in cell density. At lower concentrations, the endothelium was affected only morphologically. In experiment 3, endothelial morphology changed in control corneas and after exposure to 0.1% trypan blue for as little as 5 minutes. After 30-minute exposure, morphologic deterioration was more pronounced.
Conclusions Trypan blue was toxic in vitro to corneal endothelium and corneal fibroblasts at higher concentrations and notably longer exposure times. Toxicity was less in EMEM than in PBS
Posted by mehdi khanlari at 10:39 PM
Cystoid macular edema in a low-risk patient after switching from latanoprost to bimatoprost
American Journal of Ophthalmology May 2004
A 68-year-old man developed intense conjunctival hyperemia and cystoid macula edema after switching from latanoprost to bimatoprost 9 months after cataract surgery in an eye at low-risk for this cystoid macular edema.Bimatoprost was discontinued and diclofenac initiated. After 2 months, visual acuity and ocular hyperemia returned to baseline levels. Fundus examination revealed resolution of cystoid macula edema.
Conclusion It is possible that pseudophakic eyes that develop intense conjunctival hyperemia associated with ocular hypotensive lipids might be at higher risk for developing cystoid macula edema.
Posted by mehdi khanlari at 09:52 PM
Treatment of Previous Decentered Excimer Laser Ablation With Combined Myopic and Hyperopic Ablations
Journal of Refractive Surgery Vol. 20 No. 2 March/April 2004
To recenter the ablation zone without changing the refraction, a combination myopic and hyperopic treatment was used. The hyperopic treatment was decentered toward the initial decentered myopic ablation. A myopia ablation of near equal dioptric value was then added, but decentered in the opposite direction. The Bausch & Lomb Technolas Keracor 217 laser was used.After the first retreatment, the centration of the ablation zone was improved in 15 of the 16 eyes. All eyes with initial spectacle-corrected visual acuity loss recovered lines of visual acuity. Subjective decrease of symptoms was described as follows: nil in one eye, mild in one eye, moderate in four eyes, and marked in ten eyes. A second retreatment was needed in five eyes: in two to improve centration and in three to correct residual ametropia. The only complication (one eye) was induced decentration 180° away from the initial decentration with a 1-line spectacle-corrected visual acuity loss, and additional retreatment was required.CONCLUSIONA combination of decentered myopic and hyperopic ablation of an equivalent dioptric magnitude, each decentered 180° apart, was a useful method to correct previous excimer laser treatment decentration, with minimal alteration of refractive status that was obtained by the initial surgery.
Posted by mehdi khanlari at 09:15 PM
Persistency: A New Take on Patient Care
Review in Ophthalmology April 2004
Non-compliance, has long been studied in medicine, and further complicates the clinician’s approach to therapy. If a prescribed therapy is not achieving the desired results, is the drug ineffective or is the patient not taking it as instructed? A newer area of research receiving increasing attention, called persistency, focuses one step upstream from compliance.Persistency measures the time that a patient fills a prescription and stays on a prescribed therapy, which is a prerequisite to compliance. Persistency gains added importance for patients with chronic conditions such as hypertension or glaucoma. It is known that a substantial percentage of such patients discontinue therapy within the first six months and that the percentage discontinuing increases over time. Some of the reasons for variable persistency among alternative therapies relate to differences in the effectiveness and tolerability of medications, cost issues and understanding of the importance of taking medication.
Posted by mehdi khanlari at 08:52 PM
Radiosurgery can effectively remove xanthelasma
OSN,May,2004
Xanthelasma is rarely seen in persons younger than 30 years of age. If it appears, it usually develops after the age of 40. Xanthelasma occurs twice as often in women as in men.
A spontaneous partial involution occurs rarely in older patients. Xanthelasma is managed by cauterization, electrodessication, carbon dioxide laser ablation or serial excision. It can also be treated with topical 100% trichloroacetic acid by painting the lesion with a toothpick or the stick of a cotton stick applicator. It can be managed with a surgical excision using a patented 4.0 MHz, high frequency/low temperature radiosurgical unit. The resection of these lesions is easy with the use of radiosurgery, resulting in rapid and uncomplicated healing. Radiosurgery produces a pressureless, microsmooth, bloodless incision, much like a CO2 laser, but with less lateral heat spread and tissue alteration.
Posted by afarahi at 08:38 PM
Punctal occlusion in the management of chronic Stevens–Johnson syndrome
Ophthalmology,May,2004
In thirty-one eyes of 18 patients with chronic Stevens–Johnson syndrome lacrimal puncta were occluded by cauterization or with punctal plugs.
Concurrent improvements in subjective symptoms, vital staining scores, and VA point to the favorable effects of lacrimal punctal occlusion for the ocular surface health in chronic Stevens–Johnson syndrome.
Posted by afarahi at 08:32 PM
Topgraphic tips in Keratoconus
Review of Ophthalmology april 2004
Dr. Holladay uses four criteria to help differentiate keratoconus from lens warpage in cases where there is a “hot spot” on topography in the inferior cornea. The more criteria the suspect fulfills, the higher his suspicion that it’s keratoconus.
The first is a steep cornea. “If it’s keratoconus, the mean keratometry reading is usually greater than 46 D . The second is the location of the hot spot. “In keratoconus, the cone is rarely exactly at 6 o’clock—it’s usually at 6:30 or 5:30, that is, slightly to either side of 6 o’clock . The third criterion is the appearance of the hot spot. In a cone, it is almost circular, but with contact lens warpage the shape looks like a smile or a horizontal ellipse . The fourth parameter is the thickness of the hot spot compared to a symmetrical point above.For example, if the hot spot is 3.5 mm inferior at 5 o’clock, then you’d measure at 3.5 mm superior at 11 o’clock, normally, the inferior cornea is no more than 20 µm thinner than the corresponding value of the point above, especially in the afternoon after the patient’s been awake for several hours. Since the inferior cornea dries out more in the exposure zone during the day, it’s between 10 and 25 µm thinner as the day progresses. If the hot spot is more than 30 µm thinner than the corresponding superior point, then this is another vote for a cone.
Dr. Holladay adds that, in the majority of cases, all four parameters point to the same diagnosis, but occasionally one or two may be different. In these cases, the comparison of the thickness of the “hot spot” to the corresponding area above is key.
Posted by mehdi khanlari at 07:36 AM
Drinking and Cataract
Review of Ophthlmology April 2004
The relative risk for cataract extraction rose with increasing alcohol consumption and was more pronounced in smokers. Among women drinking more than a glass of wine (13 grams alcohol) per day and smoking >15 pack-years of cigarettes (roughly, three-quarters of a pack per day) the relative risk for cataract extraction was
Posted by mehdi khanlari at 07:12 AM
Bag versus SulcusReview of Ophthalmology April 2004
The best approach to sulcus IOL implantation is to decrease the IOL power by 0.5 D, according to a study at Boston’s Massachusetts Eye and Ear Infirmary. Investigators there reviewed records of 30 patients who underwent phacoemulsification cataract extraction and sulcus lens implantation. Of the 30 patients, 68 percent were women, and the average age was 69. The average axial length was 23.3 mm; 74 percent had clear cornea incision surgery, the rest, a scleral tunnel. The implanted sulcus lens power was reduced by 1 D in eight patients, and the average difference in the target and actual spherical equivalent at postop week four was -0.7 D. In seven patients, the sulcus lens power was reduced by 0.5 D, and the average difference was -0.4 D. The sulcus lens power was unchanged in 15 patients, and the average difference in the preop target refraction and the actual spherical equivalent in this group was -1.3 D.Decreasing the IOL power by 0.5 D was associated with the least difference between the target and postop achieved spherical equivalent. The greatest discrepancy between the target and actual refraction occurred when no adjustment was made to the lens power when implanting it in the sulcus
Posted by mehdi khanlari at 07:05 AM
Surgically Induced Astigmatism (SIA) following corneal incisions
Review of Ophthalmology April 2004
There are good reasons to pursue a small corneal incision, but avoiding surgically induced astigmatism is not one of them, say researchers at New York City’s Edward S. Harkness Eye Institute. They compared surgically induced astigmatism (SIA) following a temporal 2.6 mm corneal incision to SIA following phacoemulsification with 3.0- to 4.0-mm corneal incisions . After inserting three-piece IOLs, the surgeons enlarged the initial temporal 2.75-mm corneal incision to 3 to 4 mm to accommodate an acrylic IOL with a 6.0-mm optic (Acrysof MA60AC, n=81), an acrylic IOL with a 5.5-mm optic (Acrysof MA30BA, n=172), or a silicone IOL with a 6 mm optic (AMO SI40, n=103). They also tested a one-piece acrylic IOL with a 6.0 mm optic (Acrysof SA60AT, n=125) injected through a 2.6-mm incision.All groups were followed for at least 18 months.They detected no consistent effect of IOL type or incision size, and the surgical groups did not differ from each other or control eyes.IOL optic thickness and diameter influence minimum incision size when an IOL is inserted with a forceps. In general, the enlarged incision for the 6.0-mm acrylic three-piece IOL is slightly larger than that of a 5.5-mm acrylic IOL or a 6.0-mm silicone IOL; and all incisions for the three-piece IOLs are larger than 2.6 mm. However, SIA after these incisions is small, and all incisions appear to be astigmatically neutral. The clinician may prefer the smallest possible incision to maintain a stable chamber and to hasten recovery, but there is no detectable advantage of a sub-3.0 mm incision to SIA.
Posted by mehdi khanlari at 06:55 AM
Biometric measurement of Phakic IOLs Eyes
Review of Ophthalmology april 2004
Research at New York Medical College, Valhalla, finds that a phakic anterior chamber IOLs affect biometric measurement of axial length and can lead to clinically significant errors in IOL power calculation in eyes that subsequently develop cataracts and require extraction.They compared IOL power calculations (using the SRK formula) pre- and postop. They also retrospectively analyzed nine similar patients in the literature, looking at axial length measurement before and after PAC-IOL placement.
In the case study, AL measured through the PAC-IOL was 22.18 mm and after explantation was 22.84 mm. The first AL gave an IOL power of 23.0 D for a posterior chamber IOL. The second AL gave an IOL power of 21.9 D. The retrospective analysis showed that mean axial length was 31.5 mm when measured through the crystalline lens, but only 30.29 mm through the PAC-IOL, a statistically significant difference.To correct for this systematic error, the investigators recommend that surgeons should preserve a database of patient ALs measured prior to PAC-IOL surgery. If this data is not available, a two-staged surgery may be needed to obtain the correct IOL power.
Posted by mehdi khanlari at 06:44 AM
Are silicone IOLs contraindicated in diabetic eyes?
Review of Ophthalmology April 2004
Research in the United Kingdom suggests that, despite “abundant case reports of interactions in clinical practice,” the answer is no.Investigators reviewed the case records of all diabetic patients undergoing vitrectomy over 10 years at London’s Central Middlesex Hospital eye unit, which monitors 1,500 diabetic patients annually. Vitrectomy was performed in 0.53 percent of all monitored diabetic patients, for vitreous hemorrhage, tractional retinal detachment and rhegmatogenous RD. The rate of cataract surgery using silicone IOLs was 5 percent of all diabetic eyes (150/3,000 eyes per year). Silicone oil was used in 14 percent (11/79) of all diabetic eyes undergoing vitrectomy , in treating chronic retinal detachment, or following segmentation/ delamination. Three eyes with silicone oil (27 percent) had silicone IOLs in situ. Oil was removed at eight months in one, and is still in situ after 12 and 48 months in two other eyes. All eyes have clear axes. Two have an intact posterior capsule, the third eye underwent capsulotomy at one year. No eye developed complications related to the oil.They conclude that the risk of an adverse reaction from silicone oil-silicone IOL interaction appears to be small, despite a 14-percent rate of silicone oil use in diabetic eyes, and a rate of cataract surgery in keeping with the national average. They do not feel that the risk justifies contraindicating this IOL use in diabetic patients
Posted by mehdi khanlari at 06:33 AM
Higher Order Aberrations and Ortho-K
Review of Ophthalmology April 2004
Japanese researchers found that coma-like and spherical-like aberrations increase significantly in patients undergoing overnight ortho-k . Clinicians looking for guidance in which design of CRT lens to fit may benefit from Canadian research showing an increased treatment-zone diameter led to increased therapeutic effect. CRT may induce or exacerbate higher-order aberrations.
Posted by mehdi khanlari at 06:15 AM
May 15, 2004
Monovision LASIK Ophthalmology Times May 1, 2004
....Preoperative use of monovision contact lenses is helpful in identifying patients who have the potential to adapt successfully to monovision refractive surgery," Dr. Miranda Silva said. "However, monovision contact lens failure can be due to either contact lens intolerance or poor visual adaptation to monovision."That is one reason why monovision LASIK is offered without a contact lens trial in myopic patients undergoing refractive surgery when close to or older than the age of 40 years," . "Another reason is that further ablation of the cornea can easily be done without significant increase in risk after 3 months for patients who do not like monovision
Posted by mehdi khanlari at 11:06 PM
Ocular implants
Ophthalmology TimesMay 1, 2004
Numerous types of orbital implants are available, each with specific advantages and disadvantages.Since the Bio-Eye (Integrated Orbital Implants, San Diego) was introduced in 1985, a variety of ocular implants including hydroxyapatite, synthetic hydroxyapatite, porous polyethylene (Medpor, Porex Surgical Inc., Newnan, GA), and aluminum oxide (Bioceramic Implant, FCI Ophthalmics, Marshfield Hills, MA) have been introduced.
The most common implants in North America today are the Bio-Eye, the Medpor Implant, the Bioceramic Implant, and FCI synthetic hydroxyapatite [Canada only
Under scanning electron microscopy, many implants have pores; the aluminum oxide implant is the most porous with the most uniform number of pores.The Bio-Eye the most expensive of the implants and the polymethylmeth acryl ate sphere the least expensive.Dr. Jordan favors the aluminum oxide implant."I think that it is a more biocompatible implant than the others. The sockets of the aluminum oxide implant are quieter.In addition, it has a greater bioinertness than all other implant materials,"Wrapping materials Many wrapping materials are available and there is marketing pressure to use them. He pointed out that eye bank sclera can cost from $300 to $500 and pericardium about $700.In a review of 200 porous orbital implants wrapped in Vicryl mesh we found an incidence of 2% exposure. Vicryl mesh eliminates the need for donor tissue and the second surgical site, is readily available, has a long shelf life, and there is no risk of disease transmission .
Another area of controversy surrounding ocular implants is pegging. He explained that pegging is not beneficial for everyone, especially children, patients with a systemic disease, and those taking steroids or a chronic medication. It is also not beneficial for every physician doing or bital implants .Titanium is the pegging system of choice because it is much better tolerated than other pegging materials, and polycarbonate should be avoided."
Posted by mehdi khanlari at 10:44 PM
May 12, 2004
Clinical measures only partially account for quality-of-vision complaints after LASIK
Ophthalmology Times May 1, 2004
San Diego - Multiple factors contribute to quality-of-vision problems after LASIK, although even when taken together, preoperative and postoperative clinical measures exert a relatively minor role, according to Capt. Steven C. Schall-horn, MD . The results showed that there was some worsening of glare and halo complaints after surgery, although both diminished between 1 and 6 months. The multivariate regression analysis found level of refraction, level of complaints, and contact lens wear preoperatively, as well as postoperative UCVA and cylinder, were significantly related to postoperative complaints. Pupil size had an early, weak correlation but no long-term influence. However, all of those variables taken together explained at best only 15% of the variance in symptoms, Adaptation and perception likely play a very important role, and until we start investigating higher-order aberrations more extensively, we may never know why most patients are bothered . In the analyses of glare, the level of complaints before surgery was the strongest predictor of postoperative symptoms at both 1 and 6 months. Correlations were also found between contact lens wear and preoperative MSE, but the relationship with contact lens wear was lost at 6 months and the effect of preoperative MSE became very weak. In the analyses of halo complaints, preoperative contact lens wear was the strongest predictor at 1 month, but its influence disappeared at 6 months. The preoperative level of myopia had the second strongest correlation at 1 month and was still a significant but weak predictor at 6 months. The preoperative level of halo complaints explained a small amount of the variance at 1 and 6 months, as did postoperative UCVA, but only at 1 month.
Posted by mehdi khanlari at 04:28 PM
Single-handed injector system makes IOL
Ophthalmology Times May 1, 2004
The Royale Injector (ASICO), a single-handed injection system for implanting the AcrySof lens (Alcon), has in-corporated a plunger mechanism into the design that cataract surgeons appreciate.For a silicone IOL, it is necessary to deliver the lens slowly because it often 'jumps' into the anterior chamber; however, it is not necessary for the AcrySof because this lens does not jump," . "The method of implantation through a smaller incision by pushing the cartridge port toward the incision without inserting its tip into the anterior chamber, is easier with the Royale Injector because the handpiece is stable during injection of the lens, while with the Monarch, the tip of the cartridge moves while the screw knob is rotated."Another feature that he likes about the injection system is that the plunger tip is slightly longer than other injectors.This allows me to depress the trailing haptic of the lens so that both haptics and the optic are placed directly into the bag in one smooth movement,"
Posted by mehdi khanlari at 03:26 PM
May 11, 2004
New posterior chamber phakic IOL : StickLens (IOLTech)
Ophthalmology Times May 1, 2004
Santa Fe, Argentina - Clinical trial experience supports the conclusion that the StickLens (IOLTech), a foldable, single-piece, acrylic posterior chamber phakic IOL, is a promising option for correction of high myopia, while recent design modifications will make implantation even easier and possible through an even smaller incision, The only significant complications encountered were the development of visually significant anterior subcapsular opacities . However, development of all of those cataracts could be attributed to difficulties associated with the surgical procedure and not to the presence of the StickLens in the eye . The StickLens measures 11.5 mm in diameter and has a 6.5-mm optic that is ultrathin - only 30 µm at its center. Its hydrophilic acrylic material is very flexible and extremely smooth with a polish rugosity index of 1 to 2 nm.Viewed laterally, the StickLens has three curvature ratios. That unique design causes it literally to stick to the anterior capsule of the crystalline lens and to move forward in concert with the natural lens during accommodation in a "sucking and piston" effect. Implantation of the StickLens is performed under topical anesthesia using an injector placed through a self-sealing, temporal, clear corneal incision into a viscoelastic-filled eye. The original version of the Stick Lens, which featured four haptics and a peripheral ring around the outermost circumference, was placed through a 3-mm incision. In the new design, there are just three haptics and no peripheral ring
Posted by mehdi khanlari at 10:29 PM
Sleep apnea places patients at high risk for glaucoma
Ophthalmology Times May 1, 2004
Patients who have obstructive sleep apnea seem to have an usually high risk of glaucoma. In a study conducted at the Mayo Clinic in Jacksonville, FL, 33% of patients with obstructive sleep apnea (OSA) were found to have glaucoma.Obstructive sleep apnea syndrome (OSAS) is characterized by repeated apneic episodes during sleep as well as by daytime symptoms, including excessive daytime sleepiness, chronic fatigue, and decreased cognitive abilities. The apneas are caused by collapse of the pharyngeal airway and typically have a duration from 10 to 60 seconds.The diagnosis of OSAS is made by overnight polysomnography performed by simultaneous measurement of electroencephalography, electromyography, electro-oculography, electrocardiography, nasal and buccal airflow, respiratory movements, and pulse oximetry to measure arterial oxygen saturation. The respiratory disturbance index (RDI) is calculated from these accumulated data, and represents the total number of apneas (complete cessation of airflow) and hypopneas (partial cessation of airflow) divided by the hours of sleep. An RDI score equal to or higher than 10 in combination with typical symptoms indicates the presence of OSAS. A link between sleep apnea and the development of glaucoma was first reported by Walsh and Montplasir (Thorax 1982;37: 845-849).There was no evidence that gender, age, body mass index, or apnea-hypopnea index was related to the presence of glaucoma. The results suggested that IOP increases as the body mass index increases, and that the IOP may be lower in men than in women. He reported that the IOP increases about 0.3 mm Hg per a five-unit increase in the body mass index."We recommend that patients with obstructive sleep apnea be screened for glaucoma because obstructive sleep apnea may be a modifiable risk factor and it is easily treatable,"
Posted by mehdi khanlari at 09:41 PM
Total Opacification of Intraocular Lens Implant After Uncomplicated Cataract Surgery: A Case Series
Arch Ophthalmol. 2004;122:782-784
Opacification of intraocular lenses (IOLs) in various forms has been reported in all 4 of the varieties of lens materials available. Herein we report total opacification (optic and haptic) of a single-piece acrylic hydrophilic IOL in 5 cases, where the AquaSense IOL (Ophthalmic Innovations, Inc, Ontario, Calif) was used. In 2 of the cases, the initial diagnosis was posterior capsular opacity, and in 1 patient who had diabetes it was also thought to be nonresolving vitreous hemorrhage.
Posted by mmiraftab at 06:20 PM
May 10, 2004
Greater ablation depth than predicted in LASIK
OSN 4/6/2004
Significantly more tissue than predicted was removed by photoablation in LASIK, according to researchers at the Mayo Clinic. In the same study, there was no difference between the predicted and measured ablation depth in photorefractive keratectomyJay C. Erie, MD, and colleagues compared the predicted and achieved ablation depths in 25 eyes of 15 patients that underwent PRK and 25 eyes of 15 patients that underwent LASIK to correct refractive errors ranging from –1.5 D to –11 D. In vivo confocal microscopy was used to examine the corneas preoperatively and at 1 month postoperatively. Digital image analyses of the confocal scans were used to calculate thickness measurements.The ablation depth, an estimate of the actual photoablation depth, was obtained by measuring the surgically induced stromal thinning between the preop and the 1-month post-PRK or post-LASIK central stromal thickness.In LASIK, the measured ablation depth (81 µm) was 25% greater than the predicted ablation depth (65 µm). The difference between the measured and predicted ablation depths was positively associated with the mean ablation depth. In PRK, no difference was found between the measured ablation depth and the predicted ablation depth
Posted by mehdi khanlari at 11:24 PM
Multifocal cornea an option for presbyopia
OCULAR SURGERY NEWS EUROPE/ASIA-PACIFIC EDITION May 2004
A multizone corneal LASIK treatment, obtained using special software, can give presbyopic patients good near and distance vision with no loss of contrast sensitivity, according to a designer of the software The PAC software, which is not yet commercially available, was designed for the Nidek EC5000 excimer laser system by Alain Telandro, MD, in collaboration with Nidek engineers. Multizone presbyopic LASIK is not a way of restoring accommodation, but a way of compensating for presbyopia through corneal asphericity and multifocality obtained with laser ablation.“My work is based on the possibility offered by the Nidek laser of creating very wide optical zones. A first hyperopic treatment on a wide area is followed by a myopic treatment in the center. The aim, however, is not bifocality, but a very progressive aspheric lens, which is made possible by the smooth transition zones created by this laser,” .
Posted by mehdi khanlari at 11:15 PM
Wavefront-guided treatment can correct presbyopia, surgeons say
OCULAR SURGERY NEWS EUROPE/ASIA-PACIFIC EDITION May 2004
Effective correction of presbyopia can be obtained by modifying spherical aberration in the periphery of the cornea with just a few microns of customized photoablation . This method of presbyopic correction was developed by Franco Bartoli, MD, .The procedure is safer and far less invasive than any other surgical treatment of presbyopia. The quality of distance vision is not affected The procedure removes no more than 6 µm to 10 µm of tissue, Dr.In a study of 1,500 patients with the WASCA aberrometer, spherical aberration was found to be zero or slightly negative in the nonaccommodating eye. During accommodation, the central anterior surface of the lens vaults forward and induces positive spherical aberration. Dynamic wavefront analysis was able to quantify both accommodation and induced spherical aberration,In presbyopic eyes, the loss of accommodation produces a loss of the ability to induce spherical aberration.“I therefore assumed that, in theory, inducing an increase in spherical aberration should compensate for the loss of accommodation in presbyopic eyes. I tried this in practice, and it worked“First, we evaluate whether we are in the presence of a positive or negative spherical aberration. If it is negative, we perform an aberrometric overcorrection; if it is positive, we turn it to negative and then overcorrect it. Refraction is treated thereafter using a customized ablation program,”
Posted by mehdi khanlari at 10:38 PM
May 09, 2004
AcrySof ReStor provides good vision near and far
OSN May 2004
BARCELONA – The apodized optic design of the pseudoaccomodative Alcon AcrySof ReStor IOL may overcome the drawbacks and limitations of other multifocal implants, according to one surgeon with early experience There are still the concentric rings familiar from other multifocal lenses, but the decrease in step height is so gradual that the transition between distance, intermediate and near vision becomes a natural, smooth and imperceptible process.The ReStor has an optic diameter of 6 mm, with a central 3.6 mm diffractive pattern that adds 3.2 D power at the spectacle plane. The dioptric range is from +18 D to +25 D, but will be expanded when there are sufficient clinical results,Postoperatively, all eyes were within ±0.62 D of intended correction and uncorrected visual acuity (UCVA) at distance was 20/25 or better. Uncorrected near acuity was J2 or better in all eyes at 30 cm and intermediate UCVA was J4 or better at 60 cm. Best corrected vision was 20/20 or better in all eyes.The wavefront analysis of these lenses compared to the standard monovision AcrySof SN60 AT and to the accommodative eyeonics AT45, showed no significant difference in spherical aberrations, Dr. Carones said.“Distance vision is as good as with monofocal IOLs, with no complaint of glare and halos, and reading vision is extremely satisfactory. The only complaint is that near vision is really near, so that patients who have been presbyopic for some years have to learn how to use it again,” “The weakest point of the lens is intermediate vision, which is not as sharp as we would like it to be.”
Posted by mehdi khanlari at 06:35 AM
Sealed capsule device helps prevent PCO
OCULAR SURGERY NEWS EUROPE/ASIA-PACIFIC EDITION May 2004
One of the authors (AJM) developed a disposable device called Perfect Capsule (Milvella Pty. Ltd.), which helps selective targeting of the lens epithelial cells with a new technique called sealed capsule irrigation (SCI).Using an injection-molded silicone device , SCI isolates the internal lens capsule, including residual lens epithelial cells, from the rest of the eye. The basic idea is to seal the rhexis and then irrigate the capsular bag with an irrigating solution , which would prevent PCO. The sealing of the capsule should be perfect, so the surgeon can irrigate the capsular bag without the solution leaking into the anterior chamber. Finally the device is removed from the eye The Perfect Capsule SCI device is made of medical-grade silicone. It has an overall diameter of 7 mm and an inner diameter of 5 mm, and it was designed to temporarily seal a capsulorrhexis of less than 5 mm. The device uses a vacuum ring (similar to that used to fixate the globe during LASIK) that attaches onto the outer surface of the anterior lens capsule and seals around the rhexis. There is a channel through which an irrigating solution can be passed into the capsular bag, and through that same area a channel for the outflow of the fluid.Once the sealing has been done, trypan blue can be injected via a cannula through the opening in the Perfect Capsule meant for irrigation. The trypan blue will not leak into the anterior chamber, indicating the sealing is perfect. Then the capsular bag is irrigated with distilled water, which will not come into contact with any other structures as it passes in and out of the capsular bag. We used the air pump in the irrigation to improve the flow through the cannula.The next step is to remove the Perfect Capsule. For this the assistant disengages the lock in the syringe to break the suction. Viscoelastic is gradually injected inside the eye, then the Perfect Capsule is disengaged from the capsule with the globe stabilization rod. Once it is free in the anterior chamber, the Perfect Capsule is pulled out of the eye. Because it is soft, it is easily removed without discomfort under topical anesthesia.
Posted by mehdi khanlari at 06:21 AM
May 07, 2004
FEMTEC Laser Microkeratome Receives FDA Approval
CRST April 2004
The FEMTEC device is a femtosecond laser system for use in creating a corneal flap in LASIK patients as well as for other treatments requiring initial lamellar resection of the cornea. The FEMTEC is fully automated and features a patented and curved patient interface, which does not applanate the cornea. The FEMTEC’s solid-state femtosecond laser uses ultrashort infrared light pulses for direct intrastromal tissue interaction.
Posted by mehdi khanlari at 09:52 PM
Accommodating new designs
Eyeworld April 2004
Also on the multifocal horizon are some designs that attempt to mimic human accommodation. Here are a few innovation designs now in the wings.
• CrystaLens (eyeonics, Aliso Viejo, Calif.) — this newly approved lens allows patients to focus up close, far away, and in between
• Sarfarazi Elliptical Accommodative IOL (Bausch & Lomb, Rochester, N.Y.) — an elliptical accommodating IOL, with two lenses that are held together by a spring mechanism at the periphery that will allow for movement of one lens with respect to the other and accommodation
• SmartIOL (Medennium, Irvine, Calif.) — a thermodynamic, hydrophilic accommodating IOL, this is a stable gel, designed to go through a tiny incision and fill the entire bag. “Because it is a stable gel it will give us a high amplitude of accommodation
• Synchrony Dual Optics IOL (Visiogen, Irvine, Calif.) — this lens has two optics and when the patient focuses at near, the two lenses move closer together and the patient can accommodate
>• ThinOptX lens (ThinOptX, Abington, Va.) — this is extremely thin and has multiple prisms that focus for distance and because it’s so thin the capsular bag may be able to change the shape of this lens when the patient accommodates, Osher said.
Posted by mehdi khanlari at 02:11 PM
New double surgical glove could save time, money
Eyeworld April 2004
A high-sensitivity, double surgical glove, developed by infection control technology company Bio-Barrier (Los Angeles), was slated to be debuted late last month.The new glove features two separate layers originating from a single cuff at the wrist. It is more comfortable than wearing two separate gloves (“double gloving”), a practice in which that two layers of barrier help wipe off more pathogens from a needlestick or sharps injury than a single layer.The company’s patents allow the glove to be made of thin layers of latex or polymer while utilizing current powder-free technologies. According to company officials, the double glove will save time and money for hospitals and medical practices by reducing the time associated with double donning, by reducing the amount of packaging currently used for single glove sets, and by reducing inventory, storage and waste.
Posted by mehdi khanlari at 01:49 PM
Xibrom
Eyeworld April 2004
ISTA Pharmaceuticals (Irvine, Calif.) announced positive results from its initial analysis of the company’s U.S. Phase III clinical trials of Xibrom (0.1% bromfenac sodium ophthalmic solution). The initial purpose for development of this topical, twice-daily, non-steroidal anti-inflammatory solution is the treatment of ocular inflammation following cataract surgery.
Posted by mehdi khanlari at 01:46 PM
The problem with sutures of capsular tension ring
Eyeworld April 2004
....The study came upon the inadequacy of commonly used 10-0 prolene sutures for the procedure, when six eyes developed late symptomatic posterior chamber IOL decentration caused by breakage of those sutures. Those eyes required re-connection with 9-0 prolene sutures, but three other eyes with suture breaks required no intervention because they remained centered. The earliest suture break was at 12 months and the median occurrence was at about 18 months.Cionni recommended surgeons move away from 10-0 prolene sutures to 9-0 prolene or 8-0 ultrathin polymer-treated Gore-Tex sutures, even though the shorter needle used with them can be more difficult to manipulate. He also is studying the possibility of using other polyester sutures thought to be less biodegradable. None of the new sutures have since failed......
Posted by mehdi khanlari at 01:33 PM
May 06, 2004
ZADITOR
zaditor.com
Is a sterile ophthalmic solution containing ketotifen for topical administration to the eyes.Established Name: Ketotifen Fumarate Ophthalmic Solution :Ketotifen is a relatively selective, non-competitive histamine antagonist (H1-receptor) and mast cell stabilizer. Ketotifen inhibits the release of mediators from cells involved in hypersensitivity reactions. Decreased chemotaxis and activation of eosinophils has also been demonstrated. In human conjunctival allergen challenge studies, ZADITORwas significantly more effective than placebo in preventing ocular itching associated with allergic conjunctivitis. The action of ketotifen occurs rapidly with an effect seen within minutes after administration. ZADITORTM (ketotifen fumarate ophthalmic solution) is indicated for the temporary prevention of itching of the eye due to allergic conjunctivitis The recommended dose is one drop in the affected eye(s) every 8 to 12 hoursPatients should be advised not to wear a contact lens if their eye is red. ZADITOR? should not be used to treat contact lens related irritation. The preservative in ZADITOR?, benzalkonium chloride, may be absorbed by soft contact lenses. Patients who wear soft contact lenses and whose eyes are not red, should be instructed to wait at least ten minutes after instilling ZADITOR? before they insert their contact lenses.
Posted by mehdi khanlari at 06:37 PM
FlexMD to distribute tear test in southeastern U.S.
Ophthalmology Times May 1, 2004
Raleigh, NC - FlexMD, a distributor of dry eye diagnostics, will exclusively distribute the Touch Scientific Tear MicroAssay Test in the southeastern United States.The test determines tear protein levels and conjunctivitis by measuring lactoferrin and immunoglobin E levels. The chemistry allows doctors to determine the function of the lacrimal gland system to distinguish between allergic and non-allergic conditions.The company said the 10-minute test is fully reimbursed by most major medical insurance providers and Medicare
Posted by mehdi khanlari at 06:06 PM
Microplasmin receives orphan drug protection
Ophthalmology Times May 1, 2004
Dublin - The FDA has classified a new microplasmin compound for use in pediatric vitrectomy as an orphan drug. The drug is injected to induce posterior vitreous detachment and facilitate vitrectomy in children, in whom the vitreous is particularly adherent, which makes surgery rife with complications. Vitrectomy is often necessary to treat visual conditions such as retinopathy of prematurity (ROP), the leading cause of blindness in infants and young children. In addition to use in vitrectomies, the drug may help prevent the progression of diabetic retinopathy and protect against diabetic macular edema.
Posted by mehdi khanlari at 06:03 PM
May 04, 2004
Two Drops in One :Flura-Safe
Review of Ophthalmology April 2004
Accutome Inc. introduces Flura-Safe, an eye drop that both stains and anesthetizes the eye. Flura-Safe uses Fluorexon, a large-molecule fluorescein, ensuring that Flura-Safe will not spoil soft contact lenses. To anesthetize, this product contains benoxinate. Accutome says Flura-Safe will decrease chair time and increase patient satisfaction. Visit accutome.com.
Posted by mehdi khanlari at 11:58 PM
Handy Kit for Ortho-k Lens Care
Review of Ophthalmology April 2004
Bausch & Lomb has launched its new Boston Advanced Ortho-K Care System kit to help eye-care practitioners reinforce good lens-care practices with their orthokeratology patients. Each kit includes lens-care products designed to meet the level of care required for gas-permeable lenses: Boston Simplus multi-action solution, Boston rewetting drops, DMV remover and instructions, contact lens case, ortho-k patient care guide and a travel case. The system kit can be ordered through authorized Boston manufacturers. Visit bausch.com.
Posted by mehdi khanlari at 11:54 PM
Glaucoma during pregnancy
Eyeworld April 2004
As a result of the problems with thalidomide in the 1960s, the Food and Drug Administration set up a classification system based on teratogenesis. Drugs fall into one of five classes: Class A drugs show no risk in controlled human studies; Class B drugs show no evidence of risk in humans; in Class C drugs, the risk cannot be ruled out; Class D drugs have positive human evidence of risk; and Class X drugs are contraindicated during pregnancy.Most glaucoma medications fall into the Class C category. Brimonidine (Alphagan, Allergan, Irvine, Calif.), a Class B drug, is the exception. “Knowing that risk cannot be ruled out is not of very practical value to the physician faced with a pregnant patient who requires glaucoma medication,” Brimonidine is the only glaucoma medication that is a Class B drug, showing no evidence of risk. However, it can cause central nervous system depression and apnea in neonates,Beta-blockers are used in obstetrics for pre-eclampsia and eclampsia. However, they can cause central nervous system depression and bradycardia in the neonate.Carbonic anhydrase inhibitors are used in pregnant patients for increased intracranial pressure and hypertension, but they can cause transient metabolic disorders in the newborn.. All prostaglandins can cause contraction of uterine smooth muscle. Additionally, they can induce regression of corpus luteum. Prostaglandin F2 alpha agents are used to promote labor therapeutically in obstetrics and to induce abortion in veterinary medicine.During the first two trimesters, beta blockers, alpha-2 agonists, brimonidine, and topical carbonic anhydrase inhibitors are probably safe. Avoid prostaglandins during pregnancy
Posted by mehdi khanlari at 11:47 PM
Glaucoma and ....
Eyeworld April 2004
*Blood pressure is probably also important in glaucoma patients. Diastolic perfusion pressure is the diastolic blood pressure minus IOP. A diastolic perfusion pressure of 50 or less has been correlated with chronic open-angle glaucoma progression, but not low-tension glaucoma.
*Corneal thickness measurements allow you to categorize patients according to risk, he said. “If a patient has a pressure of more than 26 mm Hg, and he or she has a corneal thickness less than 550 µm, his or her risk of developing glaucoma in five years is around 36%, whereas someone with the same pressure but a corneal thickness of more than 588 µm has only a 6% risk.Any time a treatment decision is made, the patient’s corneal thickness should be measured
*Maybe patients with thin corneas have an optic nerve that is more vulnerable to developing glaucoma,” he said. “Additionally, perhaps facility of outflow may be different in patients with thinner corneas, regardless, the results from the OHTS trial implicate an unmeasured mediating factor other than IOP associated with thinner corneas and conversion to glaucoma
Posted by mehdi khanlari at 11:18 PM
May 03, 2004
Ocular dominance and patient satisfaction after monovision induced by intraocular lens implantation
J Cataract Refract Surg April 2004
Japan,The durations of exclusive visibility of dominant- and nondominant-eye targets were measured in 16 patients with successful monovision and 4 patients with unsuccessful monovision to determine the characteristics of ocular dominance. The dominant eye was determined using the hole-in-card test (sighting dominance). The contrast of target in nondominant eye was fixed at 100%; the contrast of target in the dominant eye varied (ie, 100% to 80% to 60% to 40% to 20%) using rectangular gratings of 2 cycles per degree that were 4 degrees in size.Conclusions:
Success and patient satisfaction in monovision patients were significantly influenced by the magnitude of ocular dominance. The balance technique seems to be a good method to evaluate the quantity of ocular dominance and prospectively evaluate the monovision technique.
Posted by alireza habibollahi at 11:46 PM
Advanced epithelial ingrowth 6 months after LASIK.
J Cataract Refract Surg April 2004
Epithelial ingrowth is a common complication of laser in situ keratomileusis (LASIK). The cause is thought to be postoperative invasion of surface epithelial cells under the flap. We present a case of advanced epithelial cystic ingrowth that caused a profound reduction in visual acuity 6 months after a second LASIK enhancement.
Posted by alireza habibollahi at 11:37 PM
Pseudokeratoconus in a patient with soft contact lens-induced keratopathy: Assessment with Orbscan I
J Cataract Refract Surg April 2004
We report a patient with soft contact lens-induced keratopathy that caused Orbscan corneal topography (Bausch & Lomb) to show features suggestive of keratoconus. In cases such as this, Orbscan should be used with other examination techniques such as Placido disk-based topography or ultrasonic pachymetry to ensure the correct diagnosis.
Posted by alireza habibollahi at 11:29 PM
Corneal keloid: Clinical, ultrasonographic, and ultrastructural characteristics
J Cataract Refract Surg April 2004
A 70-year-old man was referred to us with a 2-year, progressive, painless decrease in visual acuity in the right eye. Ocular history included extraction of a traumatic cataract with a transclerally fixated posterior chamber intraocular lens. Slitlamp examination showed a raised, white, vascularized mass covering the cornea. The lesion was removed by superficial lamellar keratectomy. Light microscopy examination confirmed the diagnosis of corneal keloid. These uncommon lesions usually develop in adults after corneal traumas, surgery, or inflammatory processes. They have also been described in children with Lowe's syndrome, Rubinstein-Taybi syndrome, and other ocular developmental disorders.
Posted by alireza habibollahi at 11:25 PM
Orbital cellulitis after phacoemulsification and intraocular lens implantation
J Cataract Refract Surg April 2004
We report a case of orbital cellulitis after uneventful phacoemulsification and intraocular lens implantation under peribulbar injection. The eyelid skin was prepared with chlorhexidine gluconate before the peribulbar injection, and the eyelid and conjunctival cul-de-sac were prepared with povidone–iodine before phacoemulsification. Five days postoperatively, the patient presented with reduced visual acuity and lid swelling. Ocular examination showed signs of orbital cellulitis, which was confirmed by a computed tomography scan. Oral erythromycin and metronidazole were given, after which the symptoms improved with successful outcomes.
Posted by alireza habibollahi at 11:22 PM
Central retinal artery occlusion after peribulbar anesthesia
J Cataract Refract Surg April 2004
We describe the development of central retinal artery occlusion (CRAO) in 2 patients after peribulbar (periconal) anesthesia during uneventful phacoemulsification. Although peribulbar anesthesia avoids direct optic-nerve injury, indirect injury presenting as CRAO may occur from vasospasm in response to the injection.
Posted by alireza habibollahi at 11:15 PM
The relation of volume with outcome in phacoemulsification surgery
British Journal of Ophthalmology 2004;88:643-646
Background/aims: High case volume has been associated with better health outcomes for a variety of procedures and conditions including coronary angioplasty, carotid endarterectomy, colorectal surgery, and various types of cancer surgery. The association of volume and outcome has important implications for patient safety and healthcare delivery planning. The relation between surgical volume and outcome has not, as far as is known, been looked at for phacoemulsification alone.
Methods: All cataract surgery performed from 1996 to 2001 by six consultant surgeons was reviewed. Using theatre logbooks and cross checking with the hospital database, the total number of phacoemulsification procedures performed per surgeon per year was calculated. The total number of operations in which it was judged that significant intraoperative complications occurred was also counted.
Results: When the data were pooled for all the surgeons there was evidence that complication rate decreased over time (Spearman’s rho = –0.319, p = 0.058). If the data were pooled from all the years and all the surgeons then there was strong evidence of a decrease in complication rate with an increase in the number of cases (Spearman’s rho = –0.63, p<0.01).
Conclusions: This study is the first to describe a possible relation between volume of surgery and the outcome (as measured by complication rates) for phacoemulsification. There are however some caveats in that the issue of case mix was not addressed and that the results are from a single unit and may not necessarily be generalisable
Posted by mmiraftab at 05:48 PM
May 02, 2004
Possible factors in post lasik keratectasia
Eyeworld jan 2003
Factors such as optical zone size, ablation depth, and intraocular pressure also may play a pivotal role in the development of ectasia, believes Maria Jose Cosentino, MD, associate director, , University of Buenos Aires, .The investigation used a computer simulation to cross these three. By leaving the same residual bed, but using different optical zones and different IOPs, the investigators were able to simulate conditions under which ectasia was likely to occur. For example, with a residual stromal bed of 370 mm with an optical zone of 5 mm and an IOP of 21-mm-Hg corneal displacement was almost 30 mm. When the optical zone was brought out to 7 mms with an IOP of 15-mm-Hg, corneal displacement went down to 16 mm. With a constant ablation depth, the corneal displacement that occurred with simulated smaller optical zones at 18.39 mm was greater than that resulting from larger optical zones, at 15.28 mm.While there is no information in the literature on the role of intraocular pressure and optical zone size in corneal ectasia after LASIK, Cosentino believes that the evidence suggests that this is potentially an important contributory factor and should be kept in mind. “We ask you to consider the use of the ocular hypotensive drugs in cases of corneal ectasia after LASIK,” Cosentino said
Posted by mehdi khanlari at 11:39 PM
Ocular antihypertensives and post lasik ectasia
Eyeworld nov 2001
In a series, McGeorge used ocular antihypertensives topically to treat late myopic regression following LASIK for high myopia.In May 1998, a patient with a refractive error of –11 D in each eye was treated with a Hansatome 160-µm head and the 217C Technolas excimer laser, a multizone treatment.“Preop and intraoperative ultrasonic pachymetry showed relatively thin corneas initially; but fortunately, we had very thin corneal flaps and the residual beds after treatment were at 227 and 232 µm,” he said.Post-LASIK refraction remained stable at 12 months and the patient was uncorrected 20/20 minus (right and left). However, at 18 months postop, she complained of the recent onset of blurred vision. Her uncorrected acuity had dropped to 20/25 and 20/40, with a myopic regression of –0.5 D and –1.5 D. Orbscan showed a relatively pre-ectasic cornea with a posterior surface forward bowing. McGeorge started the patient on two ocular antihypertensives, Timoptic XE 0.5% (timolol maleate, 5 mL, Merck) drops (once daily in both eyes), and Alphagan (brimonidine tartrate ophthalmic solution 0.15%, Allergan) drops twice daily in both eyes.She reported marked symptomatic improvement. “Her vision had improved to 20/25 in both eyes with hyperopic shift in refraction of 0.5 D and +1.82 D. She had an improved overall Orbscan appearance as well. There was anterior and posterior surface flattening after treatment with the ocular antihypertensives, and the anterior and posterior elevation map showed central flattening,” he reported.The hyperopic shift appears on the corneal surface, with the difference in optical power of +2 D, he added. At 36 months postop, the patient’s vision has remained stable while maintaining topical treatment. However, within days of stopping the drops, her vision changed. As a result, the patient plans to continue with the drops and no re-treatment is planned.
Posted by mehdi khanlari at 11:20 PM
CK and Intacs show promise for treatment of ectasia, keratoconus
Eyeworld jan 2004
Intacs (Addition Technology Inc., Des Plaines, Ill.) and conductive keratoplasty (CK) are a promising treatment for ectasia and keratoconus. However, long-term effects are not yet understood, and significant regression can be seen from one to three months after surgery. CK can be considered an enhancement tool if optimum vision cannot be provided with Intacs aloneCK and Intacs can also be considered an alternative in keratoconus patients with no central scarring and in whom penetrating keratoplasty (PK) may not be ideal.Hardten said that the following are unresolved questions about CK and Intacs:
• Is it better to do CK first or second?
• What is the long-term progression of disease?
• Do the Intacs cause long-term problems?
• Will the CK cause long-term weakening or strengthening?
• What will happen when/if these patients eventually need PK?
He concluded that it is preferable to do Intacs and CK at the same time, rather than separately.
“I treat with CK first in the periphery, which stretches the cornea down toward the inferotemporal region, because most ectasia is usually inferotemporal, he said. Then, in the same surgical setting, I put the Intacs in.”Then, he places some extra spots centrally.
Posted by mehdi khanlari at 11:08 PM
Orbital cellulitis after phacoemulsification and intraocular lens implantation
JCRS,April,2004
This is a case report of orbital cellulitis after uneventful phacoemulsification and intraocular lens implantation under peribulbar injection. The eyelid skin was prepared with chlorhexidine gluconate before the peribulbar injection, and the eyelid and conjunctival cul-de-sac were prepared with povidone–iodine before phacoemulsification. Five days postoperatively, the patient presented with reduced visual acuity and lid swelling. Ocular examination showed signs of orbital cellulitis, which was confirmed by a computed tomography scan. Oral erythromycin and metronidazole were given, after which the symptoms improved with successful outcomes.
Posted by afarahi at 07:39 PM
Stereopsis and long-term stability of alignment in esotropia
Journal of AAPOS,April,2004
Recent studies of infantile and accommodative esotropia (ET) have focused on stereoacuity as a final outcome measurement for judging the success or failure of treatment. In this study, Random-dot stereoacuity was assessed within 3 months of initial surgical alignment in 70 children with infantile ET and within 3 months of initial optical correction in 66 children with accommodative ET. At 5 years of age, adverse outcomes were assessed including loss of alignment, amblyopia, and nil stereopsis. In the infantile ET cohort, early nil stereopsis was associated with a 3.6 times greater risk of surgery for recurrent ET or consecutive exotropia and a 4.2 times greater risk for nil stereopsis at 5 years of age. In the accommodative ET cohort, early nil stereopsis was associated with a 17.4 times greater risk of surgery for ET and a 32.2 times greater risk for nil stereopsis at 5 years of age.
Conclusion :Treatment protocols designed to optimize stereoacuity outcomes promote long-term stability of alignment.
Posted by afarahi at 07:33 PM