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September 29, 2004

Intraoperative corneal cooling reduces pain after surface laser procedures

OSN Sep 2004



Intraoperative corneal cooling can decrease the incidence and the intensity of postoperative pain after PRK, laser epithelial keratomileusis and epi-LASIK procedures, according to surgeons who are using the method. When Massimo Camellin, MD, described the idea of creating an epithelial flap in LASEK rather than a stromal flap, one of his rationales was that this surface procedure reduced some of the major drawbacks of PRK — the induction of postoperative pain and stromal haze. Dr. Camellin reported a variable degree of pain in some patients after his new procedure, but in fewer cases than with PRK.Some have proposed that pain and haze formation after photoablation procedures seem to be due to an increase in corneal temperature. Reports in the early 1990s proposed that intraoperative lowering of the corneal temperature with cold balanced salt solution could substantially decrease pain and haze after PRK. However, the corneal cooling procedure for PRK never caught on, and LASIK soon became a more popular procedure because postoperative pain was reduced in comparison to PRK.Dr. Fortunato said that he performs corneal cooling by applying a small concave shield to the cornea. The instrument has been sterilized and refrigerated at a temperature of –3° to –5° C.

“The shield is placed on the cornea with plastic forceps for 40 seconds just before laser photoablation. “After laser treatment, the cooling process is repeated with a second refrigerated shield, which can again be concave for hyperopic eyes or convex for myopic eyes, to better adapt to the new corneal curvature.” In LASEK, the epithelial flap is then repositioned, and a bandage contact lens is applied. In PRK, surgery ends with the application of the contact lens.The shields are made of a chromium-plated metallic material and have a variable diameter of 5 mm to 7 mm, depending on the ablation profile used. To prevent heat transmission from the surgeon’s hands, the concave shield has a small knob on the external surface for grasping with forceps, and the convex instrument has a plastic handle that allows it to be held in position on the flattened cornea after photoablation.The bandage contact lens is removed 4 to 5 days after surgery. Postoperatively, antibiotic and nonsteroidal anti-inflammatory drops are administered for 4 to 5 days, and hyaluronic acid drops are used for 3 to 6 months.The effects of corneal cooling on the anterior stroma were recently demonstrated with confocal microscopy by Leonardo Mastropasqua, MD, and Mario Nubile, MD, using Nidek Confoscan 3 technology.“We compared the images of the anterior stroma 24 hours after PRK in eyes which had or had not received the corneal cooling treatment,” said Dr. Nubile. “The surgical trauma induced by photoablation was clearly visible in both cases, but in the eyes where Dr. Fortunato’s cooling shields were applied there was less edema, and undamaged keratocytes were visible on the surface. This demonstrates that corneal cooling reduces inflammation and cellular apoptosis, which accounts for the reduction of haze formation and pain.”

Posted by mehdi khanlari at 11:56 PM

Transepithelial customized PRK safe and effective for re-treatment cases

OSN Sep 2004



NAPLES, Italy – Transepithelial customized PRK is a safe, effective and predictable re-treatment method, according to one surgeon.PRK in which the epithelium is removed by laser rather than manually, said Alessandro Mularoni, MD, at Naples ‘04. The laser is set for a plano ablation to remove the epithelial thickness and then to perform customized refractive re-treatment.Although epithelial thickness and refraction are difficult to evaluate before a second treatment, laser removal of the epithelium with customized PRK is easier and more predictable than with manual PRK, Dr. Mularoni said.When mapping the treatment, the CIPTA software of the LaserSight LSX 2000 takes into account the epithelial component in both the measurement of visual acuity and corneal shape, he said. This way he can predict the epithelial thickness after epithelial regeneration over the center of the optical zone and adjust the quantity and pattern of ablation accordingly, he explained.Transepithelial customized PRK re-treatment has several advantages, according to Dr. Mularoni.“First of all, it is a ‘no touch’ technique, which minimizes trauma and leaves a smoother, more regular stromal surface. Re-epithelialization takes place more easily and consistently, preventing postoperative inflammation, regression and epithelial scarring,” .“The laser software calculates the exact amount of epithelium that has to be removed, sparing corneal tissue and creating a smoother transition between the new optical zone and the untreated area,”.According to Dr. Mularoni, compared with conventional PRK, the treatment requires more cooperation on behalf of the patient because the laser is in use for a longer duration. It requires a confident approach to corneal topography by the surgeon since the software interacts with topographic data and results largely depend on the accuracy of these data.

Posted by mehdi khanlari at 11:38 PM

EpiLift System receives FDA approval

OSN Sep 2004

PARIS — The EpiLift System, used in performing the epi-LASIK procedure, received U.S. regulatory approval on Friday, according to Visijet president and chief executive officer Randy Bailey. The EpiLift System uses Visijet’s patented SurEdge separator to lift an endothelial sheet of consistent thickness from Bowman’s layer before laser ablation, Mr. Bailey said. “It actually rides along the cleavage plane between the epithelium and Bowman’s layer without damaging Bowman’s layer,” Mr. Bailey said.EpiLift has now been approved in the United States for use in all ranges with the epi-LASIK procedure. The EpiLift System, developed by Gebauer and distributed worldwide by Visijet, received the European CE Mark in late 2003 and will now be available for U.S. distribution, . Dr. Lohmann said he switched to epi-LASIK more than a year ago not because his results were better with than PRK, LASIK or LASEK, or because the procedure was cheaper, but because epi-LASIK gives him consistent results without the risk of the stromal flap inherent in LASIK or the pain associated with LASEK.

Posted by mehdi khanlari at 11:29 PM

Topography-based PRK corrected astigmatism in mildly keratoconic eyes

OSN Sep 2004



PARIS — Using vector planning to create surface ablation treatment parameters produced predictable outcomes in patients with mild keratoconus undergoing refractive surgery, according to a surgeon speaking here.Noel Alpins, MD, presented results of a study evaluating vector planning for correcting astigmatism in patients with form fruste and mild keratoconus here at the European Society of Cataract and Refractive Surgeons meeting. Vector planning uses corneal topography measurements, not wavefront measurements, to calculate ablation parameters. The axes of corneal astigmatism and refractive astigmatism are plotted on a double-angle vector diagram, and the vectorial difference between the refractive and corneal astigmatism is calculated, . “The magnitudes are the same, but the angles are doubled. So when you are drawing these two together, you have a progeny called the ocular residual astigmatism, or ORA,” . This is also known as lenticular astigmatism or noncorneal astigmatism.The applied treatment is intended to reduce both corneal astigmatism and refractive astigmatism by about 50%, rather than eliminating the corneal astigmatism altogether,.“Using vector planning will result in less corneal astigmatism than treatment by refractive values alone. And refractive astigmatism values are not compromised,” he said. “Vector planning really has potential to reduce aberrations and improve spectacle corrected visual acuity. At the end of the day, the patient has less corneal astigmatism, which at the end of the day is also going to reduce any aberrations of the second order (spherical and cylinder) and third order (trefoil and coma).”

Posted by mehdi khanlari at 10:47 PM

September 28, 2004

Bleb-associated endophthalmitis: Clinical characteristics and visual outcomes

Ophthalmology Aug 2004



OphthalmologyPatients treated with tap-and-inject had a significantly worse final VA (medians, HM at 3 months and LP at 12 months) and a significantly higher rate of NLP vision than patients treated with PPV. One third of patients who underwent PPV achieved a final VA of 20/100 or better 12 months after treatment.... Conclusions: Bleb-associated endophthalmitis causes significant visual morbidity. Patients with culture-negative BAE and patients treated with prompt PPV may achieve better visual outcome.

Posted by pakravanmd at 11:08 PM

Research shows LASIK could improve psychological functioning

Eye world, september 2004



All ophthalmologists know that LASIK can enhance visual acuity, but a new study suggests the surgery could improve self-esteem, optimism, and other psychological functioning.“I definitely don’t think LASIK is going to replace a psychiatrist,”

Posted by pakravanmd at 10:41 PM

Statins and Aspirin therapy help prevent progression from dry to wet AMD

The progression of dry age-related macular degeneration to the more severe wet form of the disease may be reduced through the therapeutic use of cholesterol-lowering statins and aspirin. Also patients with CNV and AMD are less likely to take statins or aspirin and more likely to smoke.

Posted by kjalali at 07:25 AM

Topical ketorolac may help prevent development of severe ROP

Application of topical ketorolac tromethamine in premature infants seemed to reduce their risk of developing severe retinopathy of prematurity in a preliminary study. In this study 59 preterm infants with ketoralac compared to no ketorolac in 53 preterm infants. In the treatment group, 0.25 g of topical ketorolac was administered to each eye every 8 hours in infants with birthweights less than 1250 g or a gestational age less than 30 weeks. Only one infant in the ketorolac group (2.3%) developed threshold retinopathy of prematurity (ROP) and required cryotherapy. Six infants in the control group (17%) developed ROP requiring cryotherapy. Infants in the ketorolac group also required a significantly shorter duration of oxygen therapy.

Posted by kjalali at 07:16 AM

September 25, 2004

Knot up ophthalmic loose ends with new micro-tying forceps

Eyeworld Sep 2004



One of the mainstays of ophthalmic surgery is the fine art of knot throwing. This has traditionally been done outside of the eye, using the longstanding McCannel or Siepser sliding knot techniques.However, now an unusual, new pair of micro-tying forceps (MicroSurgical Technology, Redmond, Wash.) is making it possible for surgeons to actually tie the knots inside the eye instead. Ike K. Ahmed, M.D., designed the innovative forceps to circumvent problems of lens displacement, hemorrhage, and tears associated with external knot tying Dr. Ahmed, in conjunction with MST, removed any sharp edges or sharp points and designed a smooth tying platform that had a rounded edge that could be used to grasp the suture in the eye.The 23-gauge, micro-tying forceps has a curved arm that can fit through an incision of 1 mm or less.

“Each of the blades of the forceps is non-toothed, with a smooth platform design for suture grasping and tying,” . These blades can be drawn closed with a squeeze handle.



Posted by mehdi khanlari at 09:12 PM

September 24, 2004

Quantitative evaluation of regular and irregular corneal astigmatism in patients having overnight orthokeratology

http://www.ascrs.org/publications/jcrs/absjul04.html#kim

JCRS JULY 2004

To quantitatively assess changes in regular and irregular corneal astigmatism in patients having overnight orthokeratology.

Japan,A prospective study was conducted of 64 eyes of 39 patients having overnight orthokeratology for myopia. Inclusion criteria were an uncorrected visual acuity (UCVA) of 20/20 or better after treatment and a minimum follow-up of 3 months. Using Fourier series harmonic analysis, videokeratography data were decomposed into spherical component, regular astigmatism, asymmetry (tilt or decentration), and higher-order irregularity.

Results:Orthokeratology significantly reduced the manifest refraction from ?2.60 to ?0.17 D and improved the UCVA from 0.82 to ?0.11 logMAR .Regular astigmatism increased significantly from 0.53 D preoperatively to 0.63 D postoperatively The asymmetry component increased significantly from 0.35 to 0.64 D .Higher-order irregularity did not change significantly before treatment and after treatment .The amount of myopic correction correlated significantly with the increase in the asymmetry component but not with the increase in regular astigmatismConclusions:Irregular corneal astigmatism significantly increased, even in clinically successful orthokeratology cases. The effect of the changes on visual function should be studied further.

Posted by alireza habibollahi at 08:30 PM

Corneal aberrations after astigmatic keratotomy combined with LASIK

http://www.ascrs.org/publications/jcrs/absjul04.html#kim

JCRS JULY 2004



To evaluate the optical aberrations in the cornea before and after astigmatic keratotomy (AK) combined with LASIK in a group of patients with high myopic astigmatism.

24 eyes with high myopic astigmatism ( -3.50 to -6.00 D) . AK was performed as the first step to reduce astigmatism; after 2 months, the residual refractive error was corrected with LASIK. Videokeratography measurements were conducted before and after each procedure. Topography maps were used to calculate the wavefront corneal aberrations for a 6.0 mm pupil diameter. Total, coma-like, and spherical-like aberrations increased significantly from preoperatively to post LASIK (×6.34, ×2.52, and ×10.50, respectively; P<.01). Astigmatic keratotomy significantly increased coma-like (×4.04; P<.01) and spherical-like (×5.66; P<.01) aberrations. After LASIK, the coma-like aberration was significantly reduced and the spherical-like aberration was significantly increased

Conclusion: AK increased HOCA , both coma-like and spherical-like, whereas LASIK performed after AK increased the spherical-like aberration and reduced the coma-like aberration.

Posted by alireza habibollahi at 08:03 PM

LASIK versus LASEK for the correction of high myopia

http://www.ascrs.org/publications/jcrs/absjul04.html#kim
JCRS JULY 2004
Seoul, South Korea.


470 eyes of 240 patients with manifest refraction spherical components greater than –6.00 diopters (D) were assigned to 2 groups: 324 eyes (167 patients) were treated with LASIK and 146 eyes (73 patients), with LASEK. Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), remaining refractive error, corneal haze, and complications were followed in both groups for 12 months.

Conclusions: Both LASIK and LASEK were safe and effectively treated eyes with high myopia. Laser in situ keratomileusis provided superior results in visual predictability and corneal opacity.



Posted by alireza habibollahi at 07:53 PM

September 17, 2004

Stem cells stop mice going blind

News@Nature.com 16 September 2004

Experiments may herald treatment for retinal breakdown.

Some forms of human blindness might be treated with patients' own cells.An injection of stem cells saved the sight of mice who would otherwise have gone blind, researchers reported this week. The study raises the prospect that some forms of human blindness might be treated with cells from a patient's own bone marrow.

Posted by mmiraftab at 09:25 PM

Visual field attention is reduced by concomitant hands-free conversation on a cellular telephone

American Journal of Ophthalmology Volume 138, Issue 3 , September 2004, Pages 347-353

Twenty male and 21 female healthy participants performed a pretest and baseline Esterman visual field examinations with the Humphrey Systems Visual Field Analyzer II. During the consequent third examination, each participant engaged in a hands-free conversation using a cellular phone. The conversation was the same for all participants. Visual field performance parameters were compared between the second (baseline) examination, and the third (test) examination for each eye.

Results

During phone conversation, missed points increased from mean 1.0 ± 1.5 to 2.6 ± 3.4 (P ? .001) in the right eye and from 1.1 ± 1.53 to 3.0 ± 3.4 (P < .001) in the left eye. Fixation loss increased from mean 7.8% to 27.4% (P < .0001) and from 7.2% to 34.8% (P < .0001) for the right and left eyes, respectively. Test duration increased by a mean of 0.28 seconds (15%) per stimulus (P < .0001). Approximately half of missed points were inside the central 30 degrees. There was no significant difference in the performance of male and female participants.

Conclusion

We describe a new model for the quantification of the attention-diverting effect of cellular-phone conversation on the visual field. In the current study, cellular hands-free conversation caused some subjects to miss significantly more points, react slower to each stimulus, and perform with reduced precision. Legislative restrictions on concomitant cellular-phone conversation and driving may need to be based on individual performance rather than a general ban on cellular phone usage.

Posted by mmiraftab at 08:55 PM

September 13, 2004

Long-term results of LASIK after penetrating keratoplasty

Eyeworld Sep2004



LASIK is an effective method for the reduction of refractive errors caused by penetrating keratoplasty (PK), a new study finds.The study group contained 57 eyes of 48 patients. All patients were unable to wear contact lenses or glasses after PK. The minimum time from PK to LASIK was 13 months, with a range to 20 years, and all eyes had sutures removed at least 45 days before LASIK surgery. After LASIK, the follow-up ranged from three to 60 months. The mean pre-operative spherical equivalent was –4.19+ 3.38 D. The average pre-operative astigmatism was 4.67 + 2.18 D. The pre-operative best-corrected visual acuity was 20/40 or better in 42 eyes (74%). At two years, the spherical equivalent was –0.61 + 1.81 D, and the astigmatism average was 1.94 + 1.35 D for the 28 eyes with follow up available. Results showed that at two years, best-corrected visual acuity was 20/40 or better in 24 eyes (86%) and a gain in best-corrected visual acuity of one line or more was seen in eight eyes (29%).However, there were some complications. At two years, two eyes (7%) had a loss of two or more lines of best-corrected visual acuity. There were nine eyes (16%) that developed epithelial ingrowth. Cornea transplants were repeated in five eyes or 9% of this series.Surgeons concluded that while effective in rehabilitation, the method didn’t achieve the desired outcome in all cases. Complications is especially true in patients with mismatch of the donor or host cornea and in those with poor endothelial cell function, .



Posted by mehdi khanlari at 07:42 PM

Study looks into commonalities of ectasia after LASIK for myopia

Eyeworld Sep 2004



A number of characteristics associated with corneal ectasia after LASIK in myopes have been identified, according to new research.For the results, the median time to diagnosis of ectasia after LASIK was 13 months. Residual myopia in the ectasia group was –3.69 D and was significantly greater in the comparison group, -0.38 D, P<0.001. After surgery, eyes with ectasia had increased corneal toricity of 2.87 D with increased oblique astigmatism of 1.3 D relative to eyes in the comparison group 0 D, and a loss of two lines of best spectacle-corrected visual acuity (all P<0.001). Thirty-five percent of reported cases resulted in subsequent corneal transplantation.Of those reporting treatment, 35% (17/49) received PK. Rigid gas-permeable contact lenses were used to improve vision in 60% (30/49) of eyes reported.More recently, surgeons have attempted to restore optical function using Intacs corneal inserts (Addition Technologies, Des Plaines, Ill.). This surgical alternative was used in 4% (two in 49) of the eyes where treatment was reported.

Other characteristics of corneal ectasia included:



Posted by mehdi khanlari at 07:39 PM

Night driving difficulty increases after conventional LASIK

Eyeworld Sep2004



Tips about night driving after conventional LASIK

In fact, the patients, on average, experienced a decrease both in target detection and target-identification distance with and without a glare source,For instance, conventional LASIK patients, on average, had to be 32 feet closer to a business sign in order to detect it, compared to pre-operatively, The LASIK patients also had to be 36 feet closer compared to pre-operatively in order to identify it, . And with a glare source added, the patients had to be 35 feet closer to detect it and 41 feet closer to identify it, .When it came to pedestrians — certainly the more serious target to identify LASIK patients were 19 feet closer than before surgery when detection was made without glare. With a glare source, the LASIK patients had to be 33 feet closer to make the detection and 35 feet closer to identify the target, . “A one-second reduction in detection is considered significant by the National Highway Traffic Safety Administration,”But Dr. Schallhorn found no correlation between target detection/identification and pupil size.

Posted by mehdi khanlari at 07:25 PM

September 10, 2004

United States Food and Drug Administration clinical trial of the Implantable Collamer Lens (ICL) for moderate to high myopia

ophthalmology, sep, 2004

Purpose

To report on 3-year postoperative safety and efficacy outcomes with the Myopic Implantable Collamer Lens (ICL). Results: At 3 years, 59.3% had 20/20 or better VA, and 94.7% had 20/40 or better uncorrected VA if BSCVA was 20/20 and patients were targeted for emmetropia; 67.5% of patients were within 0.5 D and 88.2% were within 1.0 D of predicted refraction. The mean improvement in BSCVA ranged between 0.5 and 0.6 lines. At 3 years postoperatively, 3 eyes (0.8%) decreased by ?2 lines of BSCVA, in contrast to 40 eyes (10.8%) that improved by a similar amount. Contrast sensitivity improved postoperatively. Cumulative 3-year corneal endothelial cell loss was under 10%. Early largely asymptomatic, presumably surgically induced anterior subcapsular opacities (trace or greater) were seen in 14 eyes (2.7%), with only 2 being clinically significant. Five eyes (0.9%) of 3 patients developed nuclear opacities of grade >2 at 2 to 3 years postoperatively. Three (0.6%) ICL removals with cataract extraction and IOL implantation have been performed. Only 0.6% reported dissatisfaction; 97.1% of patients reported they would choose ICL implantation again. Incidences of patient symptoms, glare, halos, double vision, night vision problems, and night driving difficulties decreased or remained unchanged after ICL surgery.

Conclusion

Three-year results from this standardized, multicenter clinical investigation support the safety, efficacy, and predictability of ICL surgery to treat moderate to high myopic refractive errors.



Posted by pakravanmd at 09:56 PM

Comparison of various pupil dilatation methods for phacoemulsification in eyes with a small pupil secondary to pseudoexfoliation

ophthalmology, sep, 2004

Purpose

To compare 4 methods for intraoperative pupil dilatation in eyes with pseudoexfoliation syndrome and insufficient pupil size during phacoemulsification.

Intervention

Mechanical pupil dilatation with iris-retractor hooks (group I), polymethyl methacrylate (PMMA) pupil dilator-ring (Morcher, Stuttgart, Germany) (group II), Beehler pupil dilator (group III), and bimanual stretching (group IV).

Conclusions

All 4 methods used in this study were effective procedures for the mechanical dilatation of small pupils secondary to pseudoexfoliation syndrome. Iris-retractor hooks and the PMMA pupil-dilator ring are the most time-consuming techniques but have the advantage of a stable pupil size throughout the surgery. The PMMA pupil-dilator ring causes the least iris trauma. The Beehler pupil dilator and bimanual stretching technique were the least time-consuming methods for mechanical pupil dilatation.



Posted by pakravanmd at 09:48 PM

Swedish Interactive Thresholding Algorithm Fast for following visual fields in prepubertal idiopathic intracranial hypertension

ophthalmology, sep, 2004

Objective

To examine the reliability of Swedish Interactive Thresholding Algorithm Fast (SITA Fast) visual fields (VFs) in prepubertal idiopathic intracranial hypertension (IIH) and to compare whether age, gender, or severity of visual outcome influenced the reliability of VF tests.

Participants

Twenty-six prepubertal children (<11 years of age; mean age, 7.2 years) with IIH.

Testing

Children were prospectively followed up using a child-oriented program, which included SITA Fast VF tests. Age, gender, and severity of visual outcome were correlated with reliability of performance on SITA Fast VFs using a 1-way analysis of variance, point-biserial correlation, and the chi-square test for independence of observation.

Main outcome measures

Statistical analyses results that correlated the reliability of SITA Fast VFs with age, gender, and visual outcome.

Results

Three children were treated at the age of 2 years and were unable to perform automated VF tests. Four children were treated at the age of 4 years, 3 of whom were able to perform repeatable reliable SITA Fast VF tests. Forty-two eyes of 21 children had an average SITA Fast test time of 4.5 minutes for each eye, compared with 8 minutes using the Fastpac strategy. Age was not associated with reliability scores of SITA Fast tests (F = 0.971, not significant [ns]). Gender did not influence the reliability of SITA Fast VF tests (chi-square(1) = 0.669, ns), nor did severity of visual outcome (chi-square(2) = 3.348, ns). Visual deficits were observed in 55% of patients at presentation and in 27% of patients after resolution of papilledema.

Conclusions

The SITA Fast VF tests can be performed from age 4 years and offer a reliable method for shortening test time. A child-oriented follow-up program, which entails a shortened testing time, may improve outcome in prepubertal IIH.



Posted by pakravanmd at 09:36 PM

Factors associated with optic disc hemorrhages in glaucoma

ophthalmolgy, sep, 2004

Purpose

To evaluate factors associated with optic disc hemorrhages (ODHs) in patients with open-angle glaucoma.

Conclusions

Optic disc hemorrhages were associated with diabetes and aspirin use and were observed at relatively lower IOP during follow-up.



Posted by pakravanmd at 09:34 PM

Mechanism of ocular hypotensive action of bimatoprost (Lumigan) in patients with ocular hypertension or glaucoma

ophthalmology, sep, 2004

Purpose

To determine the mechanism of ocular hypotensive action of bimatoprost in patients with ocular hypertension or glaucoma.

Conclusion

As was seen in healthy normal eyes, bimatoprost increased both the pressure-sensitive and the pressure-insensitive outflows of aqueous humor in patients with ocular hypertension or glaucoma. Bimatoprost had no significant effect on aqueous humor formation.



Posted by pakravanmd at 09:30 PM

Visual field loss from primary angle-closure glaucoma

ophthalmology, sep,2004

Purpose: To assess the degree of visual field (VF) loss in subjects diagnosed with primary angle-closure glaucoma (PACG), and to compare the severity of such loss between those with symptomatic and asymptomatic disease.

Conclusions: Eyes with asymptomatic PACG often present with severe to end-stage VF loss at the time of first presentation to hospital. In contrast, most PACG eyes with previous symptomatic angle closure present with mild or moderate VF defects. The visual morbidity of PACG may be related to the finding that the asymptomatic form of the disease is visually destructive.



Posted by pakravanmd at 09:20 PM

Macugen well-received by advisory panel; points of concern remain

OSN 8/30/2004

A drug being developed for the treatment of wet age-related macular degeneration seems to slow vision loss but does not significantly improve vision, according to testimony before an advisory panel to the Food and Drug Administration on Friday.

The FDA panel reviewed studies by Pfizer and Eyetech assessing the safety and efficacy of Macugen (pegaptanib sodium injection).

The advisory panel did not formally vote on whether Macugen should be approved. The FDA presented the panel with questions regarding the data, and it will consider the panel’s opinions as the agency moves forward in its expedited approval process for the drug.

Of concern to panel members were 12 cases of endophthalmitis reported among the Macugen users. Eyetech responded that last year researchers began preparing the injection site with povidone iodine, which they said appeared to have prevented further cases of infection.

The panel also addressed potential cardiovascular concerns in association with Macugen. Macugen works by inhibiting a protein needed in blood-vessel formation, according to Eyetech. The FDA recently mandated the manufacturer of another VEGF inhibitor approved for colon cancer to warn physicians that patients on the drug have a higher chance of developing blood clots.

Posted by mmiraftab at 01:51 AM

Treatment of recurrent corneal and conjunctival intraepithelial neoplasia with topical interferon alfa 2b

Ophthalmology Volume 111, Issue 9 , September 2004, Pages 1755-1761

Seven consecutive patients with recurrent corneal and conjunctival intraepithelial neoplasia diagnosed at the University of Minnesota from July 2000 to November 2003 were studied retrospectively. All patients had a history of histologically proven primary corneal and conjunctival intraepithelial neoplasia and were treated by surgery, cryotherapy, radiation, and/or topical mitomycin C before recurrence.

Intervention

Patients with a clinical diagnosis of recurrent corneal and conjunctival intraepithelial neoplasia were treated with recombinant topical IFN2b drops (1 million IU/ml) 4 times daily until lesion resolution was noted.

Main outcome measures

A review of medical records was performed to assess the duration of and response to treatment with topical IFN2b, defined by clinical resolution of corneal and conjunctival intraepithelial neoplasia.

Results

The average age of the 7 patients at the initiation of topical IFN2b treatment for presumed recurrent corneal and conjunctival intraepithelial neoplasia was 68.7 years (range, 54–88). Six of 7 patients had successful treatment of recurrent corneal and conjunctival intraepithelial neoplasia lesions with topical IFN2b treatment. The average length of IFN2b treatment to resolution of recurrent corneal and conjunctival intraepithelial neoplasia was 14.5 weeks (range, 5–24). After treatment with topical IFN2b for recurrent corneal and conjunctival intraepithelial neoplasia, 2 patients had another recurrence of corneal and conjunctival intraepithelial neoplasia, noted at 1 year and 2 months, respectively. The average post-treatment follow-up was 11.7 months (range, 8–17) after the resolution of recurrent corneal and conjunctival intraepithelial neoplasia. No side effects of treatment were noted in any patient.

Conclusions

Topical IFN2b as a single therapeutic agent is an effective treatment of presumed recurrent corneal and conjunctival intraepithelial neoplasia. It offers the benefits of topical therapy and avoids the risks of surgical or other interventions—specifically, ocular surface toxicity, cicatricial conjunctival changes, and limbal stem cell deficiency. Larger controlled studies with longer follow-up periods are recommended to confirm the long-term efficacy and safety of this topical treatment.

Posted by mmiraftab at 01:22 AM

Predictive factors for glaucomatous visual field progression in the Advanced Glaucoma Intervention Study

Ophthalmology Volume 111, Issue 9 , September 2004, Pages 1627-1635

Kouros Nouri-Mahdavi MD

To investigate the risk factors associated with visual field (VF) progression in the Advanced Glaucoma Intervention Study (AGIS) with pointwise linear regression (PLR) analysis of serial VFs.

Five hundred nine eyes of 401 patients from the AGIS with a baseline VF score of ?16, ?7 VF examinations, and ?3 years of follow-up were selected.

This is a cohort study of patients enrolled in a prospective randomized clinical trial (AGIS). Worsening of a test location on PLR analysis was defined as a change of threshold sensitivity of ?1.00 decibels a year, with P?0.01. Visual field progression was defined as worsening of at least 2 test locations within a Glaucoma Hemifield Test cluster with PLR analysis. Multivariate logistic regression was used to determine risk factors associated with VF worsening. Intraocular pressure (IOP) fluctuation was defined as standard deviation of the IOP at all visits after the initial surgery.

The mean (± standard deviation) follow-up time and baseline AGIS score were 7.4 (±1.7) years and 7.7 (±4.4), respectively. Visual field progression was detected with PLR analysis in 151 eyes (30%). Older age at the initial intervention (P = 0.0012; odds ratio [OR], 1.30; 95% confidence interval [CI], 1.11–1.50), larger IOP fluctuation (P = 0.0013; OR, 1.31; 95% CI, 1.12–1.54), increasing number of glaucoma interventions (P = 0.01; OR, 1.74; 95% CI, 1.14–2.64), and longer follow-up (P = 0.02; OR, 1.19; 95% CI, 1.03–1.38) were associated with increased odds of VF progression. When regression analyses were repeated in eyes with and without a history of cataract extraction, IOP fluctuation was the only variable to be consistently associated with VF progression.

Conclusion

Both increasing age and greater IOP fluctuation increase the odds of VF progression by 30% (for each 5-year increment in age and 1-mmHg increase in IOP fluctuation). The higher risk conferred by IOP fluctuation was consistently observed in eyes with and without a history of cataract extraction.

Posted by mmiraftab at 01:14 AM

September 09, 2004

PTK safely treated a variety of pediatric corneal disorders in study

OSN,Sep,2004



Phototherapeutic keratectomy was found to be an “effective and safe procedure” for the treatment of several types of corneal disorders in pediatric patients, according to a long-term study.

Rudolf Autrata, MD, PhD, and colleagues at Masaryk University Hospital in, Brno, Czech Republic, reviewed the charts of 41 eyes of 41 pediatric patients who had undergone phototherapeutic keratectomy (PTK) for the treatment of superficial corneal opacities, surface irregularities, epithelial instability or re-epithelialization failure. Treatment goals included improved visual acuity and a reduction or elimination of subjective ocular discomfort. Patients ranged in age from 8 to 18 years of age. Average follow-up was 4.8 years. Of the 41 eyes, 23 underwent PTK only, and 18 underwent PTK combined with PRK to reduce preoperative myopia (11 eyes) or hyperopia (seven eyes).

Best corrected visual acuity improved in all eyes, and episodes of ocular pain, discomfort, lacrimation and photophobia diminished. Mean preoperative BCVA of 6/38 improved to 6/12 at the last follow-up exam. Eight eyes gained five or more Snellen lines of BCVA, 11 gained four Snellen lines, nine gained three lines, seven gained two lines and four gained one line. In one eye BCVA remained unchanged, and no eye lost BCVA.

The study is published in the September issue of Journal of Cataract & Refractive Surgery.



Posted by afarahi at 09:48 PM

September 07, 2004

Little difference in induced astigmatism seen with forceps, injector IOL insertion

OCULAR SURGERY NEWS 7/1/2004

Both the MemoryLens and the AcrySof fit through 3.2-mm incisions.

One of the advantages of sutureless small-incision cataract surgery is less induced corneal astigmatism. Many ophthalmologists prefer foldable, injectable lens implants for this reason. In theory, the more a wound is stretched during IOL implantation, the more induced corneal astigmatism would be expected. For this reason, we decided to compare induced corneal astigmatism with an injectable lens (Alcon AcrySof SA60AT) to a prerolled lens (CIBA Vision MemoryLens CV232). (Note: The CIBA Vision MemoryLens has since been renamed the CV232 SRE. The IOL, along with most of CIBA’s ophthalmic surgical business, was sold to the French company IOLTECH.) Both lenses can be inserted through a 3.2-mm incision. However, does one or the other cause more distortion of the surgical wound and hence more astigmatism? Keratometry was done pre- and postoperatively for both groups, and the changes in keratometry were compared.

In theory, stretching of the surgical wound would be expected to cause a flattening of the cornea at the axis of the wound, inducing corneal astigmatism. There was a surprisingly small amount of surgically induced astigmatism in both the SA60AT group and the MemoryLens group. It appears that there is no clinical difference in the amount of wound stretching and induced corneal astigmatism with insertion of either the MemoryLens CV232 or the Acrysof SA60AT IOLs.



Posted by mmiraftab at 05:19 PM

Is it time for microincision cataract surgery?

OCULAR SURGERY NEWS 9/1/2004

In an ASCRS survey, 20% of surgeons said they plan to adopt bimanual MICS this year. But some ask why do it now, before ultrathin IOLs are available?Nicole Nader

Opinion is divided over the value of adopting bimanual microincision phacoemulsification before the approval of IOLs that fit through the ultrasmall incisions. Leading cataract surgeons agree that a microincision technique is probably the future of cataract surgery, but they disagree over whether now is the time to adopt the technique.

Posted by mmiraftab at 05:09 PM

September 03, 2004

Treatment Dose-Response in Amblyopia Therapy: The Monitored Occlusion Treatment of Amblyopia Study (MOTAS)

Investigative Ophthalmology and Visual Science. 2004;45:3048-3054

Amblyopia is the commonest visual disorder of childhood. Yet the contributions of the two principal treatments (spectacle wear and occlusion) to outcome are unknown. This study was undertaken to investigate the dose-response relationship of amblyopia therapy.

CONCLUSIONS:Continuous objective monitoring of the amount of patching therapy received has provided insight into the dose-response relationship of occlusion therapy for amblyopia. Patching is most effective within the first few weeks of treatment, even for those in receipt of a relatively small dose. Further studies are needed to elucidate the neural basis for the dose-response functions.



Posted by afarahi at 11:21 PM

Dorzolamide-induced choroidal detachment in a surgically untreated eye

American Journal of Ophthalmology August 2004



Choroidal detachment is a known complication of topical hypotensive agents when used to treat eyes sensitized by prior surgery. We document the abrupt development of an extensive choroidal detachment after initiation of dorzolamide therapy in a surgically untreated eye with primary open-angle glaucoma.Choroidal detachment can occur in surgically untreated eyes after use of a topical carbonic anhydrase inhibitor.



Posted by mehdi khanlari at 07:48 PM

Optical coherence tomography (oct) macular and peripapillary retinal nerve fiber layer measurements and automated visual fields

American Journal of Ophthalmology August 2004



To investigate the structure-function relationship between optical coherence tomography (OCT) macular retinal and peripapillary nerve fiber layer (NFL) thickness and automated visual field (VF) findings Retrospective institutional study where 150 consecutive eyes (101 subjects) from a glaucoma service were included Conclusion:Macular retinal thickness, as measured by OCT, was capable of detecting glaucomatous damage and corresponded with peripapillary NFL thickness; however, peripapillary NFL thickness had higher sensitivity and specificity for the detection of VF abnormalities.





Posted by mehdi khanlari at 07:28 PM

Abnormal’ corneal topography patterns more common than normal

OSN Aug 2004





More than half the corneal topographies of refractive surgery candidates did not fall within the “normal” patterns of spherical or spherocylindrical error in a retrospective study of unoperated candidates. David Varssano, MD, and colleagues retrospectively analyzed the videokeratographies of 100 refractive surgery candidates who had not undergone surgery. Their corneal topographic patterns were computed by videokeratographer software and analyzed using statistical software. The 100 potential refractive surgery candidates included 41 women and 59 men; average age was 32, with a range from 17.5 to 63.5 years. A total of 200 eyes were analyzed. The topographic patterns were spherical (36 eyes), spherocylindrical (60), upper steep (32), lower steep (43), irregular astigmatism (9), decentered (3), suspected keratoconus (11) and probable keratoconus (6 eyes). Topography results alone were the reason for rejection of 27 eyes from surgery. After consideration, the 43 eyes with a “lower steep” pattern were also rejected, the researchers said.The authors noted that, of the nine software-calculated indices, only “keratoconus index” could distinguish between spherocylindrical and lower steep patterns.

Posted by mehdi khanlari at 07:14 PM

Most LASIK patients happy with results

OSN Aug 2004



Most LASIK patients are satisfied with the outcomes of their surgery, and most have good visual results, a review of the literature showed. Even among those with complaints, most of the reasons for their discontent could be resolved with increased patient education, the review authors suggested.Balamurali Ambati, MD, and colleagues at the Medical College of Georgia reviewed clinical trial data from the past 15 years to determine surgical outcomes and quality of vision after LASIK, according to a press release from the college.The reviewers found that 94% of patients participating in major trials across the country attained at least 20/20 vision. Further, 98% of patients attained final visual acuity of 20/25 or better, the press release said.About 25% of patients reported some night vision disturbances in the first few postoperative weeks, and about 18% reported problems with night driving in that early period. Night vision problems tended to diminish or resolve with time, according to the release; patient complaints decreased from 25.6% at 1 month to less than 5% at 1 year, Dr. Ambati said.Preoperative education is essential for refractive surgery candidates over the age of 40 years, the release noted. The literature review showed that the “happiest patients” tended to be 45 years old or younger.Patients older than 45 “must be treated with caution and only after being counseled on their continued need for reading glasses,” the review authors said. Before subjecting patients to monovision corrective surgery, Dr. Ambati suggested that physicians offer patients a monovision contact lens trial.

Posted by mehdi khanlari at 07:09 PM

Disposable tonometer comparable to Goldmann in study

OSN Aug 2004



The Tonosafe disposable tonometer takes accurate IOP measurements, even at elevated pressure levels, according to a group of Australian researchers.

With Goldmann tonometry, the mean IOP was 17.44 mm Hg. With the disposable device, the mean IOP was 17.58 mm Hg. The mean difference was not statistically relevant, the authors said.A subgroup analysis on eyes with IOPs higher than 21 mm Hg showed that the Tonosafe reading was on average 0.15 mm Hg higher than the Goldmann reading. There was a high level of correlation between the IOP measurements with the two heads, the authors said.

Posted by mehdi khanlari at 07:02 PM

Topical ketorolac may help prevent development of severe ROP


OSN Aug 2004


Application of topical ketorolac tromethamine in premature infants seemed to reduce their risk of developing severe retinopathy of prematurity in a preliminary study.Medardo Avila-Vazquez, MD, and colleagues in Argentina and Uruguay conducted the study, in which they compared treatment with ketorolac in 59 preterm infants born from January 2001 through December 2002 to no ketorolac in 53 preterm infants born from January 1999 through December 2000. In the treatment group, 0.25 g of topical ketorolac was administered to each eye every 8 hours in infants with birthweights less than 1250 g or a gestational age less than 30 weeks. Only one infant in the ketorolac group (2.3%) developed threshold retinopathy of prematurity (ROP) and required cryotherapy. Six infants in the control group (17%) developed ROP requiring cryotherapy.Infants in the ketorolac group also required a significantly shorter duration of oxygen therapy, the authors noted. No adverse effects were detected that were attributed to the ketorolac solution.The authors noted that the study results should be interpreted with caution because of the weakness of the study design. They suggested a randomized controlled trial to further assess the effectiveness of the treatment.

Posted by mehdi khanlari at 06:58 PM

Comparison of Wavefront Aberrations and Optical Quality of Eyes Implanted With Five Different Intraocular

JOURNAL OF REFRACTIVE SURGERY Vol. 20 No. 4 July/August 2004



We compared corneal and total higher order wavefront aberrations in 25 pseudophakic eyes implanted with five different types of intraocular lenses to obtain an objective evaluation of the optical quality of these pseudophakic eyes. Five IOLs per type were studied .Corneal spherical aberration was positive in all tested eyes. For a 4-mm optical zone, ocular spherical aberration was 0.0054 ± 0.0172 µm root-mean-square (RMS) in eyes implanted with the Tecnis lens, and was 0.0562 to 0.0974 µm RMS in eyes implanted with the four other conventional IOLs. A myopic refractive shift with mydriasis of -0.08 D occurred with the Tecnis IOL; it was -0.57 to -0.90 D with the conventional IOLs. Coma did not show a substantial reduction with any of the IOLs. Total wavefront aberrations showed nonsignificant reduction with the Tecnis lens. The PSF and the MTF also showed nonsignificant improvements over conventional IOLs.CONCLUSIONS The optical quality of pseudophakic eyes can be measured in vivo by aberrometers. Different IOLs resulted in measurably different outcomes. In this preliminary study, compensation of the spherical aberration observed with the Tecnis lens confirmed the theoretical predictions associated with this lens and resulted in no myopic shift in refraction with mydriasis. [J Refract Surg 2004;20:297-306]

Posted by mehdi khanlari at 06:53 PM

Hydrophilic acrylic IOLs show marked dye uptake

OSN 7/19/2004



Dyes should be used with caution in surgery with hydrophilic acrylic IOLs because the dyes can discolor this type of lens, a group of researchers found. Trypan blue, indocyanine green and fluorescein sodium caused staining of hydrophilic acrylic IOLs but no other IOL materials tested, the researchers .The PMMA, silicone and hydrophobic acrylic IOLs were not stained by the dyes. The only IOLs that changed color were the hydrophilic acrylic lenses. All three dyes caused color changes in this lens material, the authors noted. Fluorescein sodium 2% and trypan blue 0.05% stained the lens most markedly, the authors said. Both twofold and fourfold dilutions of fluorescein sodium and ICG stained the hydrophilic lens. The fourfold dilution of trypan blue did not cause a significant color change. The trypan blue stain was washed out in 6 hours; the ICG stain remained for more than 24 hours.

Posted by mehdi khanlari at 02:28 PM

Stromal thickness alone may not predict post-LASIK ectasia

Ophthalmology Times Aug 1, 2004



In the absence of other risk factors, eyes with a post-LASIK initial residual stromal thickness (RST) <250>,investigated risk factors for ectasia in a retrospective case-control study. They compared features of a non-ectatic control group of 100 eyes from patients treated at his clinic with a case population of 21 eyes (16 patients) referred to a university-based corneal practice for management of post-LASIK ectasia.The groups were also compared with respect to several other features previously reported as significant or potential risk factors for ectasia, including rates of preoperative forme fruste keratoconus, high myopia (>-10 D), oblique astigmatism, posterior corneal elevation >40 µm on Orbscan, and re-treatment. The presence of forme fruste keratoconus on topographic indices and re-treatment were significantly more common in the eyes with ectasia compared with the controls. ...read more



Posted by mehdi khanlari at 02:18 PM

Vertical diplopia requires detailed history, complete exam

Ophthalmology Times Aug 1, 2004



Vertical diplopia has an extensive differential diagnosis. However, it is im-portant to realize that if the ophthalmologist does an appropriate history and looks for a few key clues, there is rarely a case for which it is necessary to order imaging studies."The first things to determine are if the vertical diplopia is monocular or binocular, the associated symptoms, and the conditions under which it improves or deteriorates," he said.Dr. Donahue suggested a number of factors to consider. For example, if the diplopia resolves when one eye is covered, the patient also must be evaluated with the fellow eye covered. If the diplopia resolves with rest, myasthenia gravis is a possibility. If the severity of the diplopia is dependent on posture changes, there may be superior oblique palsy. If the diplopia is worse in the morning, the patient may have thyroid eye disease. When the diplopia improves with blinking, there may be an anterior segment abnormality, usually on the ocular surface, and a condition like dry eye, he suggested.

Posted by mehdi khanlari at 02:12 PM

AMO extends treatment range for silicone IOL

Ophthalmology TimesAug 1, 2004



(AMO) is offering an extended low-diopter and plano range of its Array silicone IOL.

The July 22 launch means cataract surgeons using the Array can work in 0.5-D increments from -10 to 5.5 D, including plano. The device previously was offered for the 6 to 30 D range.The new series includes OptiEdge, AMO's patented technology designed to reduce internal reflections and edge glare.

Posted by mehdi khanlari at 01:42 PM