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March 31, 2007
Dry eye after LASIK for myopia: Incidence and risk factors
Eur J Ophthalmol 2007; 17: 1 - 6
M.R. Shoja1, M.R. Besharati1
In this retrospective case series 190 eyes that underwent LASIK were examined for a dry eye syndrome. For the 190 eyes, chronic dry eye persisting 6 months or more after LASIK was diagnosed in 20 percent of the eyes. The risk for chronic dry eye was significantly associated with higher attempted refractive correction, greater ablation depth, and female sex (p=0.001).
Posted by afarahi at 11:01 AM | Comments (0)
Assessment of the Predictive Value of Intraoperative Eyelid Height Measurements in Sitting and Supine Positions During Blepharoptosis Repair.
Ophthalmic Plastic & Reconstructive Surgery. March/April 2007.
Thirty eyelids in 15 patients with bilateral aponeurotic ptosis were selected. The margin reflex distance-1 (MRD-1) was measured with the patients in the sitting position preoperatively, intraoperatively, and in the postoperative 6 weeks. MRD-1 also was measured intraoperatively with patients in the supine position. Intraoperative measurements in the sitting position more accurately predicted postoperative eyelid height than did measurements with the patient in a supine position.
Posted by afarahi at 10:40 AM | Comments (0)
March 30, 2007
Optic Neuropathy Associated With Botulinum A Toxin in Thyroid-related Orbitopathy
Ophthalmic Plastic & Reconstructive Surgery.March/April 2007.
At 3 week follow-up after botulinum A toxin injection, three patients were noted to have clinical signs and symptoms of optic neuropathy in the ipsilateral eye following injection of botulinum A toxin for restrictive myopathy. Treatment with oral steroids followed by orbital wall decompression reversed the optic neuropathy.
Conclusions: To our knowledge, this is the first report of optic neuropathy associated with botulinum A toxin injection in TRO. Clinicians should be aware of this potential vision threatening complication
Posted by afarahi at 08:13 PM | Comments (0)
March 28, 2007
The Impact of Video Games on Training Surgeons in the 21st Century
Arch Surg. 2007
A study in the February issue of Archives of Surgery finds surgeons who play video games made 37 percent fewer errors in a simulated surgery skills course, were 27 percent faster and scored 42 percent better overall than surgeons who never played video games.
Posted by kjalali at 06:50 PM | Comments (0)
Interventions for Central Retinal Vein Occlusion: An Evidence-Based Systematic Review
Ophthalmology, March 2007
A review of all randomized clinical trials finds limited level I evidence that any current treatment option can improve visual acuity. Panretinal photocoagulation can help reduce neovascularization. Hemodilution may improve vision in some patients, but the data conflict. Ongoing trials investigating intravitreal triamcinolone, anti-vascular endothelial growth factor agents and chorioretinal anastomosis offer the most hope.
Posted by kjalali at 06:44 PM | Comments (0)
Retinal Vein Occlusion and Vascular Mortality: Pooled Data Analysis of 2 Population-Based Cohorts
Ophthalmology, March 2007
An analysis of data from the Beaver Dam Eye Study and the Blue Mountains Eye Study finds that baseline presence of retinal vein occlusion was associated with a twofold higher risk of cardiovascular death among patients age 43 to 69 years. RVO was not associated with cerebrovascular death.
Posted by kjalali at 06:40 PM | Comments (0)
High-Sensitivity C-Reactive Protein, Other Markers of Inflammation, and the Incidence of Macular Degeneration in Women
Archives of Ophthalmology, March 2007
A large prospective cohort study of initially healthy women finds those with the highest levels of high-sensitivity C-reactive protein in their blood had about a three-fold higher risk for developing AMD, while those with the highest levels of sICAM-1 and fibrinogen had about a 2-fold higher risk.
Posted by kjalali at 06:38 PM | Comments (0)
March 26, 2007
Technique pearls for using iris registration
To ensure good patient outcomes with IR, Dr. Schneider recommended the following protocol:
Ensure that your technicians have acquired good useable wavescan images that are reasonably consistent with the patient’s subjective refraction.
Mark the limbus at 3 o’clock and 9 o’clock positions at the slitlamp.
Place the patient under the laser, turn on the iris registration, and check the alignment against your marks. Have your technician document the degree and direction of rotation.
If iris registration cannot be engaged, the patient is removed from under the laser and sent out for more wavescan photos. If you cannot engage IR prior to cutting the flap, there is little chance you will be able to engage after the flap is made.
After confirming IR, the flap is made and retracted, IR is again engaged, and the position is compared to pre-flap readings to be certain that the data are consistent. If you have any concerns, recapture to confirm.
If unable to engage IR despite several efforts, including light adjustments and head and chin positioning, refloat the flap and try again to engage IR with the flap back, positioned over the stroma. Engage IR if you can, and then very gently retract the flap. After confirming there is no movement of the eye, you can treat.
If unable to engage IR despite all efforts, treat using the original marks at 3 o’clock and 9 o’clock as guides, just as you would have prior to the advent of IR technology. (This occurs in no more than 1% of eyes, noted Dr. Schneider.)
Posted by mehdi khanlari at 03:27 PM | Comments (0)
March 20, 2007
The gap in surgical rate ( cataract surgery)
The number of cataract operations performed per year, per million population is called the Cataract Surgical Rate (CSR). Economically well-developed countries usually perform between 4000 and 6000 cataract operations per million people per year. India has dramatically increased its CSR in the last 10 years from less than 1500 to a figure estimated at 3600 today. However, there is little evidence as yet that this CSR of 3600 in India is sufficient to keep pace with the incidence of cataract causing acuity of less than 20/200.2 India shoulders the largest burden of global blindness. Almost 15 million of the 1.08 billion world population is visually challenged and 52 million visually impaired. In most of Africa, China and the poorer countries of Asia the CSR is often less than 1000.
The major reasons for low cataract surgical rates in developing nations include:
• Fear of surgery
• Low demand because of poor visual results
• Lack of eye surgeons in rural areas
• No knowledge of where to seek help
• No escort
• Monetary reasons
Posted by mehdi khanlari at 10:12 PM | Comments (0)
New technique for microincision cataract surgery
A new technique called truly endocapsular microincision cataract surgery (TECMIS) uses two corneal incisions of 1.4 mm and two microcapsulorrhexis of 1 to 1.5 mm to maintain the integrity of the capsular bag as much as possible.TECMIS helps the cataract surgeon accomplish two goals of cataract surgery: achieving a less invasive surgery that results in a prompt recovery and creating a future possibility to reach an accommodative effect by injecting adequate materials in the capsular bag, allowing patients to have good sight at all distances.Performing TECMISFirst, the surgeon creates two clear cornea incisions of 1.4 mm and then two mini-capsulorrhexis of 1.4 mm diameter incision—in the peripheral area of capsular sac are performed. The mini-rhexis are started by making a tiny capsular tear with a needle cystotome and completed with forceps for microincision cataract surgery (MICS). I use the 23G capsulorrhexis forceps (Janach, Como, Italy) because it allows for control of the required maneuvers.Then, to avoid positive pressure on the capsular sac, fill the anterior chamber with a sufficient, but not excessive, ocular viscoelastic material.Next, perform the phacoemulsification. I have used the Pulsar 2 (Optikon, Rome) with the phaco tip for MICS with an external diameter of 0.9 mm.
During endocapsular phaco, the anterior chamber remains filled with the viscoelastic and a cut silicone sleeve is used to provide external irrigation and cooling in order to protect against corneal burns. An extra BSS bottle is used for the irrigation cannula or chopper.Then use the phaco tip to create a central tunnel (not a groove) and enter the irrigation cannula. In the case of harder nuclei, use an irrigating chopper (Janach, Como, Italy) instead. Sculpt the nucleus by varying the strategy according to its hardness. And soft lens cases can be emulsified without chopping.It is important to be sure that both the irrigating cannula and phaco tip remain inside the sac during the procedure. If the cannula is not in place, the bag may collapse and rupture, and if the phaco tip is not in place, it may cause capsular tears.....
Posted by mehdi khanlari at 09:45 PM | Comments (0)
Pre-operative scoring system predicts phaco case difficulty
Eyeworld March 2007
A study, published in the December issue of BMC Ophthalmology, found the scoring system named Habib to be a viable predictor of the difficulty of phacoemulsification, thereby allowing appropriate phacoemulsification case selection for trainees. Scott G. Fraser, M.D., Sunderland Eye Infirmary, Sunderland, U.K., and colleagues, evaluated Habib, a scoring system for the prediction of risk or likelihood of posterior capsule rupture during phacoemulsification surgery, on a sample of consecutive phacoemulsification cases undertaken by senior surgeons at a single ophthalmic unit over a three-week period (170 cases). The researchers scored each case using a potential difficulty scoring system. Immediately post-op, each case was given two scores by the operating surgeon (who was masked with regard to the potential complication score). The first score indicated the perceived difficulty of the case while the second score indicated the degree of experience that they thought a trainee would require in order to have performed the same case without complication. Using Cuzick’s non-parametric test for trend, the study authors found evidence for a trend of increasing perceived difficulty with increasing potential difficulty score (P=0.05), and of increasing experience required with increasing potential difficulty score (P<0.001). The study authors concluded that Habib’s potential difficulty scoring system can be used to inform the surgeon of the likely difficulty of a phacoemulsification case and to aid selection of appropriate cases for trainees prior to surgery
Posted by mehdi khanlari at 09:45 PM | Comments (0)
Stronger olopatadine solution more effective and as safe as weaker solution
Pataday (olopatadine HCl 0.2%, Alcon, Fort Worth, Tex.) is twice as strong as its predecessor, Patanol (olopatadine HCl 0.1%, Alcon) but its just as safe and is the only once-per-day antihistamine on the market, ...almost 50% of the U.S. population has allergies, and of that group, 72% suffer from ocular symptoms. Itchiness and redness are the key symptoms to look for,..but chemosis, eyelid swelling and tearing also are symptoms.
These symptoms characterize both seasonal allergic conjunctivitis (SAC) and perennial allergic conjunctivitis (PAC. PAC is set off by dust, mold and dust mites, whereas SAC is typical of ragweed.
Antihistamines are the most effective in reducing all of the symptoms,... there are several antihistamines on the market, but they all are approved by the Food and Drug Administration (FDA) for treating either itchiness or redness. Patanol, however, is approved for treating both.
Dr. Mah said that when a physician is seeing a patient with allergies, the physician should ask the patient what drugs they are using including any over-the-counter drugs.
Posted by mehdi khanlari at 12:56 PM | Comments (0)
Andogsky syndrome variant: atopic dermatitis with ocular allergy and bilateral cataract
There are a couple of considerations when dealing with patients with Andogsky syndrome, said Dr. Pflugfelder. “If there is any steroid component of the cataract, you’ve got to minimize the steroid use, otherwise it could make the cataracts worse, particularly in a child or young adult,” he said. “That adds a bit of a challenge because steroids are the only thing that work really well for both of these conditions.”
The second consideration is eye rubbing, which can be linked to retinal detachments. “You have to ask them to avoid eye rubbing,” he said. “The eye is chronically really itchy, so they’re constantly rubbing it.” To help curb the itching, Dr. Pflugfelder recommends one of the newer antihistamine mast-cell stabilizing drops such as Patanol or Elestat along with judicious use of topical steroids. In addition, using Restasis along with careful application of a low-potency steroid may help, he said.
These patients inevitably end up on steroids, said Dr. Sheppard. “Antihistamines are candy for the severe atopic individual,” he said. Another agent that can help such patients is Xolair (omalizumab, Novartis Pharmaceuticals, East Hanover, N.J.). While Xolair is indicated for asthma, Dr. Sheppard has found it very useful for patients who have atopic ocular disease.
Also, the signature leathery skin around the eye can be problematic. “Nobody has really developed a good skin cream to put around these people’s eyes, specifically for that indication.” Dr. Sheppard has used FML (fluorometholone, Allergan) ointment in such cases with some success. The downside, however, is that it comes in a small tube. “If you can get a patient off oral steroids and make his eyes better, it’s well worth the cost,” he said. Otherwise, if steroids are problematic, patients end up on the same type of drugs used to treat cancer.
Posted by mehdi khanlari at 12:51 PM | Comments (0)
March 15, 2007
Adalimumab in the therapy of uveitis in childhood
British Journal of Ophthalmology 2007;91
Chronic anterior uveitis in children often takes a serious course. Despite various immunosuppressive drugs some children do not respond sufficiently and there is a high risk of them becoming seriously disabled. Anti-TNF alpha therapy has been shown by our group and others to be mostly ineffective (Etanercept) or partly effective (Infliximab) with the risk of anaphylactic reactions. Here we report on 18 young patients treated with Adalimumab (Humira®), a complete humanised anti-TNF alpha antibody.
For our group of children with long lasting disease our results show that Adalimumab was effective or mildly effective against the arthritis in 81%, but in uveitis in 88%. While these results regarding arthritis are comparable with other TNF-alpha blocking drugs (Etanercept), Adalimumab seems to be much more effective against uveitis than Etanercept. Anaphylactic reactions, found in a previous study from our group after Infliximab treatment, were not seen with Adalimumab. The necessary dosage and the treatment period, which probably have to be defined individually for each patient, remain unclear.
Posted by mriazi at 10:46 PM | Comments (0)
Intracameral phenylephrine to prevent floppy iris syndrome during cataract surgery in patients on tamsulosin
Eye (2007) 21
Method Seven patients who were on systemic tamsulosin for benign prostatic hypertrophy received intracameral phenylephrine before capsulorexhis during their cataract surgery.
Results There was a significant reduction in the amount of mobility of the iris, reduction in the expected fluttering, and sustained papillary dilatation.
Conclusion Intracameral phenylephrine is a simple and effective tool to prevent the effects of floppy iris syndrome in those patients undergoing cataract surgery who are on systemic tamsulosin.
Posted by mriazi at 10:43 PM | Comments (0)
March 10, 2007
Nuclear cataracts leading cause for angle-supported phakic lens explantation
In a study investigating the reasons for angle-supported phakic intraocular lens (IOL) explantation, researchers found that nuclear cataracts were the most frequent reason.In a recent issue of Ophthalmology, Jorge L. Aliу, M.D., Ph.D., professor and chairman, Ophthalmology Department, Miguel Hernandez University, Spain, and his colleagues performed a consecutive retrospective series of 100 eyes of 66 patients who underwent phakic angle–supported IOL explantation.
The main outcome measures were visual acuity, refraction, and endothelial cell density. According to the study, the main causes of explantation were cataract development (64%), progressive endothelial cell loss (24%), and pupil ovalization (10%).They reported that 92 of the cases underwent bilensectomy; two cases underwent phakic IOL exchange; four cases underwent concomitant phakic IOL explantation and penetrating keratoplasty; and two cases underwent simple explantation of a phakic IOL
From the research, the investigators determined that bilensectomy, which is explanting the phakic IOL followed by phacoemulsification of the crystalline lens, was effective and maintained the refractive benefits obtained with phakic IOL implantation. Few cases developed severe endothelial cell loss, and most of those were related to certain types of phakic IOLs.Source: Alio JL, Abdelrahman AM, Javaloy J, et al. Ophthalmology 2006; 113(12):2213-20.
Posted by mehdi khanlari at 01:06 PM | Comments (0)
Erythropsia revisited
JCRS Pages 548-549 (March 2007)
We report a case of unilateral erythropsia lasting 1 week that occurred 18 years after cataract extraction and intraocular lens (IOL) implantation. The unaffected eye was pseudophakic and had an IOL with ultraviolet (UV) light protection; the affected eye had an IOL without UV light protection.
Posted by alireza habibollahi at 09:31 AM | Comments (0)
Healon5 in the management of intraoperative expulsive hemorrhage
JCRS Pages 545-547 (March 2007)
We present a patient with systemic hypertension, glaucoma, and previous vitrectomy who experienced a large expulsive choroidal hemorrhage during a procedure to reposition and iris fixate a subluxated intraocular lens. Liberal use of sodium hyaluronate 2.3% (Healon5) resulted in cessation of the hemorrhage, allowing completion of the case. Healon5 may cause cessation of bleeding through a tamponade effect and thus be useful in treating patients experiencing an intraoperative expulsive hemorrhage.
Posted by alireza habibollahi at 09:28 AM | Comments (0)
Cyclodialysis cleft secondary to removal of an anterior chamber phakic intraocular lens
JCRS Pages 542-544 (March 2007)
We present a patient who had decreased visual acuity and hypotony in the left eye 2 months after removal of an anterior chamber phakic intraocular lens (pIOL). Gonioscopy demonstrated a cyclodialysis cleft at the 6 o'clock position in the region of the IOL footplate, which was confirmed by ultrasound biomicroscopy. A cyclodialysis cleft formation is one possible complication of pIOL removal. Careful gonioscopy evaluation before removal of pIOLs should be mandatory to assess the amount of fibrosis and the presence of synechia between the IOL and the surrounding tissues.
Posted by alireza habibollahi at 09:25 AM | Comments (0)
Unusual complication after LASIK: Eyelash under the flap
JCRS Pages 540-541 (March 2007)
We report a 70-year-old man who had uneventful laser in situ keratomileusis (LASIK) to correct the refractive error in the right eye. The patient returned 5 weeks later complaining of irritation and pain in that eye. Examination revealed an eyelash under the edematous LASIK flap with surrounding infiltrates. The anterior chamber was quiet. The flap was lifted and the eyelash removed. Epithelial cells were removed from the flap interface. Postoperatively, the patient developed a mild diffuse lamellar keratitis that resolved rapidly with topical corticosteroid treatment. At 5 months, the uncorrected visual acuity was 20/20−2, with mild haze in the inferior interface. Large, visually significant foreign bodies under a LASIK flap should be promptly removed for a good visual outcome. To our knowledge, this is the first report of a post-LASIK complication due to an eyelash under the flap.
Posted by alireza habibollahi at 09:22 AM | Comments (0)
Acute rhegmatogenous retinal detachment immediately following LASIK
JCRS Pages 536-539 (March 2007)
We report a case of acute rhegmatogenous retinal detachment (RRD) after laser in situ keratomileusis (LASIK) surgery in a highly myopic patient. Fourteen hours postoperatively, the uncorrected visual acuity was counting fingers in the left eye. Slitlamp examination revealed significant anterior chamber reaction with fibrin-like material. Fundus examination revealed 2 inferior retinal horseshoe tears associated with an RD. Preoperative fundus examination with scleral depression may detect predisposing retinal lesions in highly myopic patients. Further study is required to evaluate the relationship between LASIK, acute postoperative RRD, and predisposing factors.
Posted by alireza habibollahi at 09:18 AM | Comments (0)
Artisan iris-fixated toric phakic and aphakic intraocular lens implantation for the correction of astigmatic refractive error after radial keratotomy
JCRS Pages 531-535 (March 2007)
We report 2 patients who had RK to correct myopia. The first patient developed a postoperative hyperopic shift and cataract. Nine years post RK, she had intracapsular cataract extraction and implantation of an Artisan aphakic intraocular lens (IOL). Twenty years post RK, hyperopia and astigmatism progressed to +7.0 −5.75 × 100 with a best corrected visual acuity (BCVA) of 20/20. Due to contact lens intolerance, the Artisan aphakic IOL was exchanged for an Artisan toric aphakic IOL. Three months later, the BCVA was 20/20 with +1.0 −0.50 × 130. The second patient demonstrated residual myopic astigmatism 6 years after bilateral RK and had become contact-lens intolerant. An Artisan toric phakic IOL was implanted in both eyes. Four months later, the BCVA was 20/25 with a refraction of +0.25 −1.0 × 135 and 20/20 with a refraction of −1.0 × 40. Both patients were satisfied with the visual outcom
Posted by alireza habibollahi at 09:14 AM | Comments (0)
Implantation of Artisan toric phakic intraocular lens following Intacs in a patient with keratoconus
JCRS Pages 528-530 (March 2007)
We report a 24-year-old man with bilateral keratoconus in whom Intacs (Addition Technology, Inc.) were implanted in both eyes. The procedure was followed by Artisan toric phakic intraocular lens (Ophtec) implantation to correct the residual myopic and astigmatic refractive error.
Posted by alireza habibollahi at 09:12 AM | Comments (0)
Penetrating keratoplasty versus intrastromal corneal ring segments to correct bilateral corneal ectasia: Preliminary study
JCRS Pages 488-496 (March 2007)
To describe the outcomes over time in patients with corneal ectasia pathology treated with intrastromal corneal ring segments (Intacs, Addition Technology, Inc.) in 1 eye and penetrating keratoplasty (PKP) in the other eye.
A nonrandomized comparative study and analysis of retrospective data comprised 17 patients who had PKP in 1 eye and Intacs implantation in the other eye. Patients were classified into 2 groups: asymmetric (different grade of keratoconus in each eye) and symmetric (same grade of keratoconus in both eyes). Parameters analyzed included UCVA, BCVA, and keratometry (flat and steep values and astigmatism readings). Follow-up after PKP was at 24 hours and 6 and 24 months and after Intacs implantation, at 24 hours and 3 and 10 months.
Results
In both groups, UCVA improved and the corneal shape was normal. No patient lost a line of acuity, and BCVA improved in both groups.
Conclusions
Eyes with Intacs had a shorter recovery time than eyes having PKP. The eyes with Intacs had no complications. Complications in eyes with PKP included cataract, graft rejection, and elevated intraocular pressure. Thus, Intacs segments may delay or prevent the need for a corneal graft, although longer follow-up is needed.
Posted by alireza habibollahi at 09:07 AM | Comments (0)
Analysis of centration of Intacs segments implanted with a femtosecond laser
JCRS Pages 484-487 (March 2007)
To analyze the centration of intrastromal ring segments (Intacs, Addition Technology, Inc.) implanted using a femtosecond laser in eyes with keratoconus.
In a retrospective noncomparative case series, the distance of deviation of the intrastromal ring segment from the pupillary center was evaluated in 59 eyes of 39 keratoconic patients after tunnel creation with a femtosecond laser. The distance of deviation of segments from the pupillary edge and direction of decentration were analyzed using the anterior segment analyzer of the Pentacam Scheimpflug photographic camera (Oculus Opticgerate GmbH).
Results
Intacs were successfully implanted in all eyes. The mean horizontal deviation was 788.33 μm ± 500.34 (SD) (range 30 to 2450 μm), and there was a temporal displacement in all eyes. The mean vertical deviation was 370.83 ± 343.17 μm (range 0 to 1690 μm), and there was an inferior displacement in 28.81% of eyes and superior displacement in 66.10% of eyes. There was no vertical displacement in 3 eyes (5.08%).
Conclusion
During applanation for Intacs correction by a femtosecond laser, the cornea and pupil are not in their natural position, which leads to decentration and misalignment of the segments.
Posted by alireza habibollahi at 09:02 AM | Comments (0)
Infectious and noninfectious keratitis after LASIK: Occurrence, management, and visual outcomes
JCRS Pages 474-483 (March 2007)
To retrospectively review the occurrence, treatment, and visual outcomes associated with various etiologies of keratitis as a postoperative complication of LASIK at an academic surgical center.
The charts of 5618 post-LASIK patients (10 477 eyes) were reviewed for the development of keratitis. Occurrence rates, management regimens, and final best spectacle-corrected visual acuity (BSCVA) were reported for infectious and noninfectious keratitis etiologies.
Results
Post-LASIK keratitis was diagnosed in 279 eyes. The keratitis was diagnosed as infectious in 33 eyes (12%) and as noninfectious in 246 eyes (88%). Infectious cases included 5 eyes (15%) with herpes simplex keratitis (HSV), 18 (55%) with adenoviral keratitis, and 10 (30%) with nonviral (including bacterial, fungal, and parasitic) keratitis. Of noninfectious cases, 193 (78%) were classified as diffuse lamellar keratitis (DLK), 36 (15%) as staphylococcal marginal hypersensitivity, and 17 (15%) as localized debris-related keratitis.
Conclusions
The occurrence of post-LASIK keratitis was 2.66%, with DLK being the most common diagnosis overall. The occurrence of noninfectious keratitis (2.34%) was 7.5 times greater than the occurrence of infectious keratitis (0.31%). Adenoviral keratitis had the best visual outcomes overall, with all 18 patients achieving 20/20 BSCVA. In contrast, all 5 eyes with HSV keratitis lost 1 or 2 lines of BSCVA. Excluding adenoviral keratitis, infectious etiologies had significantly worse visual outcomes than noninfectious etiologies at the 20/40 and 20/20 levels (P = .0013 and P<.001, respectively).
Posted by alireza habibollahi at 08:55 AM | Comments (0)
Asphericity of the anterior human cornea with different corneal diameters
JCRS Pages 465-473 (March 2007)
To measure the anterior corneal asphericity (Q) with different corneal diameters.
Methods
Thirty-six eyes of 36 patients were evaluated using a videokeratoscope, and the Q-values were recorded. Topographic data were also analyzed using Vol-CT 6.89 software (Sarver & Associates, Inc) to obtain the Q-values with different corneal diameters (3.0 mm, 4.0 mm, 5.0 mm, 6.0 mm, and 7.0 mm). Variable Q models of corneal sagittal height were compared against models assuming constant Q-values obtained with the Medmont E300 videokeratoscope (Medmont Pty. Ltd.) and a standard Q model of −0.26.
Results
The peripheral rate of change in corneal Q with different corneal diameters increased as corneal astigmatism increased. As a result, differences in the sagittal height between the constant model and variable model were evident beyond the central 3.0 mm area. There were significant differences between low and high astigmatic corneas in Q-values measured by the Medmont along the flattest meridian (P = .004) and Q-values obtained with Vol-CT software with a 7.0 mm corneal diameter (P = .026).
Conclusions
There were differences in sagittal corneal height calculations considering constant or variable models of Q. Concern arises when surgical interventions depend on corneal Q-values to predict the outcomes. Surgeons should be aware which procedure is behind Q computing by different corneal topographers and that a constant Q-value cannot reflect the actual shape of the cornea as significant departures from the actual sagittal height can arise depending on which Q-value is assumed.
Posted by alireza habibollahi at 08:48 AM | Comments (0)
Proper wound construction to prevent short-term ocular hypotony after clear corneal incision cataract surgery
Samuel Masket, MD, Shaleen Belani, MD
To evaluate the stability of 2.2 mm and 3.0 mm clear corneal cataract incisions with square or nearly square surface architecture.
A retrospective chart review of 60 patients who had clear corneal cataract extraction between January and September 2006 was conducted. Fifty patients had clear corneal cataract extraction with a square 2.2 mm incision and 10 patients with a nearly square 3.0 mm incision. For the 2.2 mm incision subset, cataract surgery and intraocular lens implantation were accomplished through an unenlarged 2.2 mm clear corneal cataract incision using the Alcon Infiniti unit and an Ultrasleeve for infusion. For the 3.0 mm subset, the Allergan Sovereign unit was used. Intraocular pressure (IOP) was measured intraoperatively at the conclusion of each procedure with a Schiötz or Barraquer tonometer and set between 15 mm Hg and 20 mm Hg. Wound sealing was confirmed by intraoperative Seidel testing in all cases. Intraocular pressure was measured by a Tono-Pen (Medtronic) or Goldmann applanation tonometry between 2 hours and 6 hours after the conclusion of each procedure.
Results
The mean postoperative IOP was 19.2 mm Hg (median 18 mm Hg; range 11 to 35 mm Hg) in the group with a 2.2 mm square incision and 16.6 (median 16.0 mm Hg; range 10 to 25 mm Hg) in the group with a 3.0 mm nearly square clear corneal incision. No patient had an IOP less than 10 mm Hg, and there was no evidence of hypotony or wound leakage by Seidel testing in either group.
Conclusions
Clear corneal wounds of square or nearly square surface architecture that are meticulously checked for sealing were stable postoperatively as demonstrated by the absence of hypotony and wound leakage. In the presence of a sealed clear corneal wound, IOP remained reasonably stable relative to the level set at the conclusion of the procedure.
Posted by alireza habibollahi at 08:38 AM | Comments (0)
Proper wound construction to prevent short-term ocular hypotony after clear corneal incision cataract surgery
Samuel Masket, MD, Shaleen Belani, MD
To evaluate the stability of 2.2 mm and 3.0 mm clear corneal cataract incisions with square or nearly square surface architecture.
A retrospective chart review of 60 patients who had clear corneal cataract extraction between January and September 2006 was conducted. Fifty patients had clear corneal cataract extraction with a square 2.2 mm incision and 10 patients with a nearly square 3.0 mm incision. For the 2.2 mm incision subset, cataract surgery and intraocular lens implantation were accomplished through an unenlarged 2.2 mm clear corneal cataract incision using the Alcon Infiniti unit and an Ultrasleeve for infusion. For the 3.0 mm subset, the Allergan Sovereign unit was used. Intraocular pressure (IOP) was measured intraoperatively at the conclusion of each procedure with a Schiötz or Barraquer tonometer and set between 15 mm Hg and 20 mm Hg. Wound sealing was confirmed by intraoperative Seidel testing in all cases. Intraocular pressure was measured by a Tono-Pen (Medtronic) or Goldmann applanation tonometry between 2 hours and 6 hours after the conclusion of each procedure.
Results
The mean postoperative IOP was 19.2 mm Hg (median 18 mm Hg; range 11 to 35 mm Hg) in the group with a 2.2 mm square incision and 16.6 (median 16.0 mm Hg; range 10 to 25 mm Hg) in the group with a 3.0 mm nearly square clear corneal incision. No patient had an IOP less than 10 mm Hg, and there was no evidence of hypotony or wound leakage by Seidel testing in either group.
Conclusions
Clear corneal wounds of square or nearly square surface architecture that are meticulously checked for sealing were stable postoperatively as demonstrated by the absence of hypotony and wound leakage. In the presence of a sealed clear corneal wound, IOP remained reasonably stable relative to the level set at the conclusion of the procedure.
Posted by alireza habibollahi at 08:38 AM | Comments (0)
March 09, 2007
Impact of Dry Eye Syndrome on Vision-Related Quality of Life
American Journal of Ophthalmology, March 2007
An analysis of participants in two, large, randomized studies finds that those with dry eye had significantly more problems with reading, professional work and computer use, compared with controls. However only women participants with dry eye had significantly more problems with driving, men with dry eye did not.
Posted by afarahi at 08:47 PM | Comments (0)
Intraocular Lens Exchange due to Incorrect Lens Power
This retrospective review of 22 eyes that underwent IOL exchange finds that incorrect corneal power was the most common reason for the unexpected refractive error, followed by incorrect axial length measurement and inserting a wrong IOL. The authors suggest that errors in one eye should be considered a warning to modify the IOL calculation for the second eye.
Posted by afarahi at 08:44 PM | Comments (0)
Surgeon Volumes and Selected Patient Outcomes in Cataract Surgery: A Population-Based Analysis
Ophthalmology,March,2007
A review of administrative health records in Ontario, Canada finds the average complication rate among surgeons performing more than 1,000 cataract surgeries per year is 0.1 percent. The rate for 50 to 250 surgeries per year is 0.8 percent; for 251 to 500 surgeries, 0.4 percent and for 501 to 1,000 surgeries, 0.2 percent. Overall, the rate was less than 0.5 percent.
Posted by afarahi at 08:32 PM | Comments (0)
Avastin may be beneficial for patients with ischemic retinal vein occlusions
<u>Academy Express – Academy Member Communication March 8, 2007
This prospective study of seven patients (seven eyes) with macular edema associated with ischemic central or hemicentral retinal vein occlusion were treated with 2.0 mg of Avastin at 12-week intervals. At 25 weeks, all patients experienced favorable macular changes and stabilized or improved BCVA.
Posted by mriazi at 02:33 PM | Comments (0)
Bausch & Lomb recalls ReNu MultiPlus due to trace amounts of iron
Academy Express – Academy Member Communication March 8, 2007
The company voluntarily recalled about 1.5 million bottles after getting three customer reports of discolored solution. No one was harmed and the possibility of a serious adverse event is remote. Bausch & Lomb said the iron could cause the cleaner to lose effectiveness earlier than normal.
Posted by mriazi at 02:25 PM | Comments (0)
March 03, 2007
Autologous Transplantation of the Retinal Pigment Epithelium and Choroid in the Treatment of Neovascular Age-Related Macular Degeneration
Ophthalmology March 2007
Results
Successful viable grafts were seen in 11 patients. Three patients had good visual function on the grafts, with mean logarithm of the minimum angle of resolution (logMAR) improving from 0.88 to 0.79 and maintained beyond 1 year. Operative complications occurred in 8 patients, including retinal detachment in 5 patients and hemorrhage affecting the graft in 4 patients. The mean visual acuity over the whole cohort fell from logMAR 0.82 to 1.16. The excised RPE choroid could also be genetically modified outside the eye with a viral vector applied within the time frame of the operation.
Conclusions
Autologous RPE transplantation can in principle restore vision in neovascular AMD, but surgical complications remain high. The possibility for ex vivo gene transfer to the free graft of RPE may widen the scope of this procedure to include gene therapy or adjunctive molecular treatments for AMD.
Posted by mriazi at 09:40 PM | Comments (0)
Autologous Translocation of the Choroid and Retinal Pigment Epithelium in Patients with Geographic Atrophy
Ophthalmology March 2007
Results
Preoperative visual acuity (VA) ranged from 20/800 to 20/40 (mean, 0.6±0.4 logarithm of the minimum angle of resolution), and reading vision from 1.1 to 0.5 logRAD (mean, 0.8±0.2). Three patients were unable to read. Six months after surgery, VA ranged from hand movements to 20/32, with an increase of ≥5 letters in 2 eyes. Two patients without reading ability preoperatively were able to read after surgery. Reading was possible in a total of 8 patients after 6 months (1.3–0.4 logRAD). In 7 patients who were observed for 1 year, VA remained stable (±1 line) in 5 eyes and decreased in 2 eyes between 6 months’ and 1 year’s follow-up. In all eyes but 2, revascularization was visible on indocyanine green angiography as early as 3 weeks after surgery. Autofluorescence of the RPE was independent of revascularization of the graft and persisted throughout follow-up. Four eyes had unstable fixation and/or extrafoveal fixation before surgery. Two of these eyes stabilized during follow-up. Areas overlying atrophic areas demonstrated low threshold sensitivities that persisted after translocation of a free graft with only limited recovery. Revisional surgery due to proliferative vitreoretinopathy was required in 5 eyes.
Conclusions
The translocation of a full-thickness graft usually results in a vascularized and functioning graft in patients with geographic atrophy, although is associated with a high risk of complications and visual loss. Longer follow-up is necessary to learn about the long-term survival and functionality of the graft.
Posted by mriazi at 09:33 PM | Comments (0)
Retinal Vein Occlusion and Vascular Mortality: Pooled Data Analysis of 2 Population-Based Cohorts
Ophthalmology March 2007
Results
Of 8384 baseline participants, 96 (1.14%) had RVO at baseline (BDES, n = 38; BMES, n = 58). Over 12 years, 1312 (15.7%) died of cardiovascular-related conditions and 341 (4.1%) died of cerebrovascular-related conditions. Age-standardized vascular mortality rates were 26.0% and 5.3%, respectively, in persons with RVO and 17.1% and 4.5%, respectively, in those without RVO. After adjusting for age, gender, body mass index, hypertension, diabetes, smoking, glaucoma, and study site, RVO was not associated with cardiovascular-related mortality (HR, 1.2; 95% CI, 0.8–1.8) or cerebrovascular-related mortality (HR, 0.9; 95% CI, 0.4–2.1) among participants of all ages. However, in persons aged less than 70 years, baseline RVO was associated with higher cardiovascular mortality (combined BDES and BMES: HR, 2.5; 95% CI, 1.2–5.2; BDES: HR, 2.5; 95% CI, 0.9–6.9; BMES: HR, 2.1; 95% CI, 0.7–6.8).
Conclusions
Retinal vein occlusion in persons aged 43 to 69 years may signal a doubling of the risk of cardiovascular mortality.
Posted by mriazi at 09:22 PM | Comments (0)
Relationship between Optical Coherence Tomography–Measured Central Retinal Thickness and Visual Acuity in Diabetic Macular Edema
Ophthalmology March 2007
There is modest correlation between OCT-measured center point thickness and visual acuity, and modest correlation of changes in retinal thickening and visual acuity after focal laser treatment for DME. However, a wide range of visual acuity may be observed for a given degree of retinal edema. Thus, although OCT measurements of retinal thickness represent an important tool in clinical evaluation, they cannot substitute reliably as a surrogate for visual acuity at a given point in time. This study does not address whether short-term changes on OCT are predictive of long-term effects on visual acuity.
Posted by mriazi at 09:17 PM | Comments (0)
March 02, 2007
Intrasession and intersession repeatability of the Pentacam system on posterior corneal assessment in the normal human eye
JCRS Pages 448-454 (March 2007)
To study the intrasession and intersession repeatability of the Pentacam system (Oculus Inc.) in measuring the posterior corneal shape.
Methods
The posterior corneal shape in 1 eye (randomly selected) was measured with the Pentacam system. Three consecutive readings were taken for intrasession repeatability analysis. Measurements were repeated 1 to 2 weeks later for intersession repeatability analysis. The anterior best-fit sphere (BFS) and posterior BFS at the 5.0 mm and 8.0 mm zones, as well as the elevation of the posterior cornea at these 2 zones, were compared.
Conclusions
Pentacam provided good performance in assessing the posterior cornea. To improve the intersession repeatability, it is suggested that 3 consecutive readings, rather than 1 image, be taken to generate an average BFS for analysis. When comparing the posterior corneal elevation between sessions, an average BFS generated from the first visit should be used for elevation calculation.
Posted by alireza habibollahi at 09:41 PM | Comments (0)
Assessment and reproducibility of anterior chamber depth measurement with anterior segment optical coherence tomography compared with immersion ultrasonography
JCRS Pages 443-447 (March 2007)
To measure ACD with an anterior segment AS-OCT and a standard US A-scan using an immersion technique and to assess repeatability, reproducibility, and correlations of the measurements.
The central ACD was measured 5 times with AS-OCT (Visante, Carl Zeiss Meditec) using its chamber tool and 5 times with a US A-scan device (UltraScan Imaging System, Alcon Laboratories) using an immersion method. The measurements were performed consecutively by 2 independent observers.
Results
The mean ACD measured with AS-OCT was 3.12 mm and 3.11 mm . The repeatability was 0.8% and 1.9% , respectively. The reproducibility was 0.23%. The reliability coefficient with AS-OCT was 99.6%. The mean ACD measured with immersion US A-scan was 2.98 mm and 2.95 mm . The repeatability was 6.4% 1 and 8.5% . The reproducibility was 0.88%. The reliability coefficient was 87.1% for US A-scan measurements. The difference between ACD values with AS-OCT and values with US A-scan was statistically significant (P = .02). The correlation (r) between AS-OCT and US A-scan was 0.732 and 0.802.
Conclusions
AC Depth measurements were significantly deeper with AS-OCT than with US immersion A-scan. Repeatability of ACD measurements was better with AS-OCT than with immersion US, and reproducibility was equal with the 2 methods.
Posted by alireza habibollahi at 09:32 PM | Comments (0)
Correlation of pupil size with visual acuity and contrast sensitivity after implantation of an apodized diffractive intraocular lens
JCRS Pages 430-438 (March 2007)
To determine whether pupil size is correlated with visual acuity and contrast sensitivity at all distances in eyes with an apodized diffractive intraocular lens (IOL).
Six months after surgery, the best corrected distance visual acuity, best distance-corrected near visual acuity, intermediate visual acuity, and distance contrast sensitivity under photopic (85 cd/m2) and mesopic (5 cd/m2) conditions were measured in 670 eyes of 335 consecutive patients who had implantation of the AcrySof ReSTOR Natural IOL (SN60D3, Alcon). Pupil diameters in distance vision were measured using a pupillometer.
Results
The logMAR best corrected distance acuity was significantly better with larger pupils , whereas logMAR best distance-corrected near acuity was significantly worse with larger pupils For all pupil diameters, intermediate visual acuity worsened significantly as the distance of the test increased . Statistically significant differences in photopic and mesopic contrast sensitivity at all spatial frequencies were found between the small-pupil and large-pupil groups . Distance photopic contrast sensitivity and mesopic contrast sensitivity were better in patients with large pupils than in patients with small pupils.
Conclusions
A larger pupil was correlated significantly with better distance visual acuity and with worse near visual acuity. For all pupil diameters, intermediate visual acuity worsened significantly as the distance of the test increased. Distance contrast sensitivity was better with larger pupils at all spatial frequencies in bright-light and dim-light conditions.
Posted by alireza habibollahi at 09:26 PM | Comments (0)
Correlation of pupil size with visual acuity and contrast sensitivity after implantation of an apodized diffractive intraocular lens
JCRS Pages 430-438 (March 2007)
To determine whether pupil size is correlated with visual acuity and contrast sensitivity at all distances in eyes with an apodized diffractive intraocular lens (IOL).
Six months after surgery, the best corrected distance visual acuity, best distance-corrected near visual acuity, intermediate visual acuity, and distance contrast sensitivity under photopic (85 cd/m2) and mesopic (5 cd/m2) conditions were measured in 670 eyes of 335 consecutive patients who had implantation of the AcrySof ReSTOR Natural IOL (SN60D3, Alcon). Pupil diameters in distance vision were measured using a pupillometer.
Results
The logMAR best corrected distance acuity was significantly better with larger pupils , whereas logMAR best distance-corrected near acuity was significantly worse with larger pupils For all pupil diameters, intermediate visual acuity worsened significantly as the distance of the test increased . Statistically significant differences in photopic and mesopic contrast sensitivity at all spatial frequencies were found between the small-pupil and large-pupil groups . Distance photopic contrast sensitivity and mesopic contrast sensitivity were better in patients with large pupils than in patients with small pupils.
Conclusions
A larger pupil was correlated significantly with better distance visual acuity and with worse near visual acuity. For all pupil diameters, intermediate visual acuity worsened significantly as the distance of the test increased. Distance contrast sensitivity was better with larger pupils at all spatial frequencies in bright-light and dim-light conditions.
Posted by alireza habibollahi at 09:26 PM | Comments (0)
Fellow-eye comparison of posterior capsule opacification rates after implantation of 1CU accommodating and AcrySof MA30 monofocal intraocular lenses
JCRS Pages 413-417 (March 2007)
To PCO and Nd:YAG capsulotomy rates between the AcrySof MA30 intraocular lens (IOL) (Alcon) and the 1CU IOL (HumanOptics) in a fellow-eye comparison.
Thirty patients who had bilateral cataract surgery with a 1CU IOL prospectively randomly allocated to 1 eye and an AcrySof MA30 monofocal IOL to the other eye were examined. Best corrected distance visual acuity was recorded using the Early Treatment Diabetic Retinopathy Study logMAR chart. Digital retroillumination images of the posterior capsule were taken with the pupil dilated and analyzed with POCO software.
Results
Eyes with the 1CU IOL had significantly higher PCO rates than eyes with the MA30 IOL at all time points. By 2 years after surgery, 50% of eyes with a 1CU IOL had required Nd:YAG capsulotomy compared with no eyes with an MA30 IOL. There was no significant difference in visual acuity at any time point when post Nd:YAG capsulotomy was taken in to account.
Conclusions
The 1CU IOL has 4 broad optic–haptic junctions where the square-edged barrier is breached; this appeared to allow passage of lens epithelial cells, leading to an increase in PCO. However, the increased PCO cannot be attributed to this alone as the 1CU is hydrophilic, a factor known to be associated with higher PCO rates.
Posted by alireza habibollahi at 08:36 PM | Comments (0)
Contrast sensitivity after implantation of a spherical versus an aspherical intraocular lens in biaxial microincision cataract surgery
JCRS Pages 393-400 (March 2007)
To determine whether implantation of a microincision intraocular lens (IOL) with a modified anterior surface, designed to compensate for the positive spherical aberration of the cornea in eyes of cataract patients, results in improved pseudophakic quality of vision in pseudophakic eyes after biaxial microincision phacoemulsification.
In a nonrandomized parallel cohort investigation, the visual performance of 52 eyes of 52 patients unilaterally implanted with the aspherical Acri.Smart 36 A IOL (Acri.Tec) were compared with those of 25 eyes of 25 age-matched patients unilaterally implanted with the spherical Acri.Smart 46 S IOL (Acri.Tec). Eight weeks after surgery, the following parameters were assessed: UCVA, BCVA, pupil size under various illumination conditions, high-contrast and low-contrast visual acuities, photopic and mesopic contrast sensitivities, capsulorhexis size, and wavefront aberration of the cornea and eye. The primary clinical endpoint of the comparison was defined as the area under the cycles per degree (cpd) curve of the contrast sensitivity profile.
Results
The aspherical IOL group and the spherical IOL group did not differ in baseline characteristics. The median age was 71 years and 68% were women in the aspherical group versus 69 years and 62% women in the spherical group. The preoperative median UCVA was 20/80 in both groups. The UCVA, BCVA, pupil size, and capsulorhexis size were not statistically different between the 2 groups. Furthermore, no clinically relevant or statistically significant between-group differences were observed in the primary clinical endpoint. The median postoperative low mesopic contrast sensitivity without glare was 73 cpd in the aspherical group and 84 cpd in the spherical group (P = .624); a similar tendency was observed under high mesopic conditions (median 80 cpd and 83 cpd, respectively) (P = 1.000). Implantation of both IOL types resulted in a negative spherical aberration Z40, which was significantly different between the 2 groups (median −0.09 μm aspherical and −0.29 μm aspherical at a pupil size of 4.5 mm) (P<.001).
Conclusions
No clinically relevant postoperative differences in contrast sensitivity were observed between the aspherical microincision IOL and the spherical equivalent model. The development of microincision IOLs, which fit through corneal incisions smaller than 2.0 mm and improve night-driving conditions (eg, reduction of glare), could optimize modern biaxial cataract surgery.
Posted by alireza habibollahi at 07:54 PM | Comments (0)
Proper wound construction to prevent short-term ocular hypotony after clear corneal incision cataract surgery
JCRS Pages 383-386 (March 2007)
Samuel Masket, MD, Shaleen Belani, MD
To evaluate the stability of 2.2 mm and 3.0 mm clear corneal cataract incisions with square or nearly square surface architecture.
A retrospective chart review of 60 patients who had clear corneal cataract extraction between January and September 2006 was conducted. Fifty patients had clear corneal cataract extraction with a square 2.2 mm incision and 10 patients with a nearly square 3.0 mm incision. For the 2.2 mm incision subset, cataract surgery and intraocular lens implantation were accomplished through an unenlarged 2.2 mm clear corneal cataract incision using the Alcon Infiniti unit and an Ultrasleeve for infusion. For the 3.0 mm subset, the Allergan Sovereign unit was used. Intraocular pressure (IOP) was measured intraoperatively at the conclusion of each procedure with a Schiötz or Barraquer tonometer and set between 15 mm Hg and 20 mm Hg. Wound sealing was confirmed by intraoperative Seidel testing in all cases. Intraocular pressure was measured by a Tono-Pen (Medtronic) or Goldmann applanation tonometry between 2 hours and 6 hours after the conclusion of each procedure.
Results
The mean postoperative IOP was 19.2 mm Hg in the group with a 2.2 mm square incision and 16.6 mm Hg in the group with a 3.0 mm nearly square clear corneal incision. No patient had an IOP less than 10 mm Hg, and there was no evidence of hypotony or wound leakage by Seidel testing in either group.
Conclusions
Clear corneal wounds of square or nearly square surface architecture that are meticulously checked for sealing were stable postoperatively as demonstrated by the absence of hypotony and wound leakage. In the presence of a sealed clear corneal wound, IOP remained reasonably stable relative to the level set at the conclusion of the procedure.
Posted by alireza habibollahi at 07:48 PM | Comments (0)
Combined cataract surgery and 25-gauge sutureless vitrectomy for posterior lentiglobus
JCRS Pages 380-382 (March 2007)
Javier Moreno-Montañés, MD, PhD, Jesús Barrio-Barrio, MD, PhD, Alfredo García-Layana, MD, PhD
Combined cataract surgery and sutureless vitrectomy were performed in a 2-year-old boy with posterior lentiglobus. After an anterior capsulotomy was made, the lens nucleus was aspirated without hydrodissection to avoid posterior capsule rupture. The cortex was carefully aspirated because the central posterior capsule moved up and down during irrigation and aspiration. A pars plana vitrectomy was then performed with the sutureless 25-gauge system for an anterior vitrectomy with a posterior capsulotomy. A +27 diopter AcrySof intraocular lens (IOL) (Alcon) was implanted with the haptics in the bag and the optic behind the posterior capsulotomy with optic capture. Two months postoperatively, the IOL was centered and there were no complications. This surgical technique is easy and effective. It avoids complications, facilitates IOL implantation behind the posterior capsule, and improves the external appearance of the eye immediately postoperatively.
Posted by alireza habibollahi at 07:44 PM | Comments (0)
Endothelial keratoplasty technique for aniridic aphakic eyes
JCRS Pages 376-379 (March 2007)
Marianne O. Price, PhD, Francis W. Price Jr., MD, Rafael Trespalacios, MD
We describe special techniques to visualize the donor tissue in Descemet's stripping endothelial keratoplasty and to prevent the tissue or stripped recipient Descemet's membrane from dropping onto the retina. The techniques were used successfully to treat corneal decompensation in 3 consecutive cases with no iris or lens present. The results indicate that with careful planning and a good technique, aniridic aphakic patients can benefit from the rapid corneal rehabilitation provided by endothelial keratoplasty.
Posted by alireza habibollahi at 07:36 PM | Comments (0)
Variant of the big bubble technique in deep anterior lamellar keratoplasty
JCRS Pages 371-375 (March 2007)
Pierre Fournié, MD, François Malecaze, MD, PhD, Julien Coullet, MD, Jean-Louie Arné, MD
We describe a variant of the big-bubble technique that involves placement of a stromal corneal nick and nontraumatic intrastromal insertion of a blunt cannula following anterior lamellar keratectomy. The goal of this technique is to reduce the risk for intraoperative corneal perforation and to obtain a large air bubble between Descemet's membrane and the corneal stroma. Deep anterior lamellar keratoplasty is easier and safer with this technique.
Posted by alireza habibollahi at 07:32 PM | Comments (0)
Eye drop to be investigated as an adjunctive therapy to anti-VEGF injections for wet AMD
INDUSTRY NEWS
Othera Pharmaceuticals, Inc. reported that pre-clinical data shows the compound OT-551 has a “synergistic effect” when added to either Lucentis or Avastin treatment. The company hopes the eye drop will ultimately be used to obtain even better visual acuity outcomes with fewer Lucentis injections.
Posted by kjalali at 07:02 AM | Comments (0)
Correlations Between Retinal Nerve Fiber Layer and Visual Field in Eyes With Nonarteritic Anterior Ischemic Optic Neuropathy
AJO, February 2007
Optical coherence tomography yielded higher correlations between visual field sensitivity with RNFL thickness than scanning laser polarimetry. OCT may also provide a quantitative measurement of ganglion cell loss in the pale optic disk and should be considered in the evaluation of patients with NAION after swelling of the optic disk has resolved.
Posted by kjalali at 06:59 AM | Comments (0)
Central corneal thickness and correlation to optic disc size: a potential link for susceptibility to glaucoma
BJO, January 2007
An analysis of 137 patients with POAG finds that central corneal thickness is inversely correlated to optic disc area. Thicker corneas may indicate the presence of a substantially smaller, and thus more robust, optic nerve head, while thinner may have larger and more deformable optic discs.
Posted by kjalali at 06:55 AM | Comments (0)
March 01, 2007
Effects of Long-term Zinc Supplementation on Plasma Thiol Metabolites and Redox Status in Patients With Age-related Macular Degeneration
">AJO Feb 2007Methods
This was an ancillary study of the Age-Related Eye Disease Study (AREDS). Subjects with AMD were randomized to one of four treatment groups: (1) antioxidants (vitamin C, 500 mg; vitamin E, 400 IU; and beta carotene, 15 mg), (2) zinc (80 mg zinc oxide, 2 mg cupric oxide), (3) antioxidants plus zinc, or (4) placebo. At 20 and 80 months after randomization, blood specimens were collected and analyzed for glutathione (GSH), oxidized glutathione (GSSG), cysteine (Cys), and cystine (CySS).
Results
Although zinc supplementation had no apparent effect on plasma thiol/disulfide redox status at the first blood draw, the group of patients receiving zinc supplementation at the second blood draw had significantly less CySS compared with those not receiving zinc (54.9 vs 64.1 μM; P = .01). There was a time-dependent oxidation of the plasma GHS pool and was not affected by zinc supplementation.
Conclusions
Because increased CySS level is associated with aging, oxidative stress, and age-related diseases, the apparent prevention of increased CySS by zinc supplementation warrants additional investigation.
Posted by mriazi at 10:55 PM | Comments (0)
Anti-VEGF Bevacizumab (Avastin®) for Radiation Optic Neuropathy
AJO Feb 2007
Methods
At The New York Eye Cancer Center, a patient symptomatic of decreased vision because of RON was treated with intravitreal bevacizumab (1.25 mg). Main outcome measures included visual acuity, appearance of the optic nerve, fundus photography, angiography, and optical coherence tomography/scanning laser ophthalmoscopy (OCT/SLO).
Results
Within one week, her vision improved from 20/32 to 20/20 with a reduction in optic disk hemorrhage. At six weeks, evidence of both decreased hemorrhage and optic disk edema was documented by photography, angiography, and OCT/SLO. At the three and five-month follow-up visits, the hemorrhages resolved, and her disk margins were sharp. There were no ocular or systemic side effects.
Conclusions
Intravitreal bevacizumab was tolerated, improved vision, and reduced hemorrhage as well as optic disk edema (angiographic leakage). Anti-VEGF therapy (e.g. bevacizumab) should be investigated for both ocular and nonocular radiation neuropathy.
Posted by mriazi at 10:54 PM | Comments (0)
Vitreal Penetration of Oral and Topical Moxifloxacin in Humans
AJO Feb 2007
Methods
Twenty-four patients were assigned to one of four dosing groups: control (n = 3), which received no medication; oral (n = 8), which received two 400 mg oral doses of moxifloxacin before surgery; topical (n = 8), which received one drop of topical moxifloxacin 0.5% every 15 minutes for the hour preceding surgery; and combined (n = 5), which received two 400 mg oral doses and one drop of topical moxifloxacin 0.5% hourly for 18 hours prior to surgery. Vitreous samples were obtained and analyzed.
Results
Control, below quantifiable levels; oral, 1.553 ± 0.33 μg/ml; topical, 0.027 μg/ml; and combined, 2.219 ± 0.71 μg/ml. One topical patient developed postoperative endophthalmitis.
Conclusions
In contrast to topical moxifloxacin, oral moxifloxacin achieves significant levels in the noninflamed human vitreous.
Posted by mriazi at 10:51 PM | Comments (0)
Choroidal Detachment Following the Use of Tamsulosin (Flomax)
AJO Feb 2007
Results
A 65-year-old man underwent uncomplicated cataract extraction and placement of a posterior chamber intraocular lens. The patient subsequently developed three separate episodes of choroidal detachments in the operated eye. Each episode was preceded by treatment with an α1-adrenoceptor antagonist.
Conclusions
Tamsulosin may cause adverse ocular effects including recurrent choroidal detachments. α1A is the dominant α-adrenoceptor in the rabbit choroid, and the mechanism for choroidal detachment in this patient could include some effect of antagonists like tamsulosin on these receptors.
Posted by mriazi at 10:48 PM | Comments (0)
Visual acuity after high-dose intravitreal triamcinolone acetonide in selected ocular diseases
Eye advance online publication 16 February 2007
Conclusions Improvement in vision after intravitreal triamcinolone monotherapy is highest in non-ischaemic diseases with an intraretinal macular oedema such as pseudophakic cystoid macular oedema; it is lower in partially ischaemic diseases with intraretinal macular oedema such as diabetic macular oedema or retinal vein occlusions; and it is lowest in diseases with a primarily subretinal location of the disease such as exudative age-related macular degeneration. For the latter diseases, intravitreal triamcinolone monotherapy is, therefore, no longer up-to-date, particularly with the upcoming intravitreal application of vascular endothelial growth factor blocking drugs. For diseases with intraretinal oedema, the rule of thumb may be that intravitreal triamcinolone increases vision as much as retinal ischaemia and tissue destruction by the underlying disease allow it. The rise in intraocular pressure is higher in relatively young patients with uveitis than in elderly patients with other reasons for macular oedema.
Posted by mriazi at 10:25 PM | Comments (0)