Internal limiting membrane peeling in macular hole surgery.

PURPOSE: To evaluate prospectively the ability to peel epiretinal membranes and to correlate the degree of membrane peeling to anatomic success rates. DESIGN: Consecutive, noncomparative, interventional case series. PARTICIPANTS: One hundred ninety-three patients. METHODS: The extent of membrane peeling and other intraoperative features were correlated to endpoints. MAIN OUTCOME MEASURES: Anatomic success (inducing hole closure), visual acuity of 20/50 or better, and visual improvement of two or more Snellen lines. RESULTS: One hundred ninety-three eyes were eligible for the study by virtue of having a minimum follow-up interval of 6 weeks. The overall anatomic success rate was 93% in these cases. There was a two-line or more improvement in 72%; 56% attained 20/50 or better visual acuity. The internal limiting membrane was peeled completely in 23%, partially in 43%, and not at all in 34%. The degree of internal limiting membrane peeling was not correlated with the duration of the hole or rate of two-line visual improvement, but was inversely correlated with the rate of anatomic success (P = 0.045). Final visual acuity was correlated with a better preoperative visual acuity, shorter preoperative duration of macular hole, and more complete internal limiting membrane peeling. CONCLUSIONS: Peeling of the internal limiting membrane is not essential for anatomic or visual success in macular hole surgery, but it may be a means to standardize inducement of the proper degree of gliosis. Excessive, unsuccessful attempts at internal limiting membrane peeling may decrease visual success. Techniques delivering a more reproducible, complete, atraumatic peeling of the internal limiting membrane should be studied.

Preservation of vision through Weiss ring after dense vitreous hemorrhage.

PURPOSE: To report an unusual case of retained vision through a Weiss ring in the setting of dense vitreous hemorrhage. METHOD: Case report of a 55-year-old woman with a 23-year history of type 1 diabetes mellitus who presented with new onset of blurred vision in the left eye as a result of a dense vitreous hemorrhage. RESULTS: The patient had received full scatter laser photocoagulation for proliferative diabetic retinopathy in the right eye several years earlier and reported previous resolving episodes of vitreous hemorrhage in the left eye. Best-corrected visual acuity in the left eye was hand motions at 3 feet. However, with careful head positioning visual acuity improved to 20/40 through a small clear central island. Examination of the left fundus showed a dense vitreous hemorrhage with a clear, mobile opening in the posterior hyaloid corresponding to the Weiss ring. The retina could be partially visualized only through the area of the Weiss ring. CONCLUSIONS: This unusual case demonstrates the anatomical relationship between the posterior hyaloid and Weiss ring.

Clinical assessment of the piggyback bifocal contact lens system.

PURPOSE: We performed a qualitative and quantitative assessment of contact lens performance at 1 and 6 months among 24 patients enrolled in the Piggyback Bifocal Contact Lens Study. METHODS: We fit 24 presbyopic patients with the Piggyback Bifocal Contact Lens System (i.e., a plano soft lens with a 9.4 mm cutout portion on which a bifocal RGP lens rides or "piggybacks"). Patients were evaluated prior to inclusion in the study and then at one month and six months after obtaining their lenses. Evaluations included slit lamp examination, evaluation of visual acuity at near and distance, and subjective rating of the patients' comfort. RESULTS: At one month, 61% of patients had Snellen acuities of 20/30 or better, 79% had near acuities of J2 or better, and 60% rated their comfort as good or very good. At six months, 100% of patients had Snellen acuities of 20/30 or better, 90% had near acuities of J2 or better, and 86% of patients rated their comfort as good or better. Twelve patients did not complete the study due to their decision to drop the study. CONCLUSIONS: The Piggyback Bifocal Contact Lens System is a well-tolerated, satisfactory means of optical correction for the motivated presbyope.

Evaluation of a delivery system providing long-term release of cyclosporine.

OBJECTIVES: To examine the clearance of cyclosporine after intravitreal injection and to assess the kinetics and toxic effects of an intravitreal device that provides sustained delivery of cyclosporine. METHODS: Rabbits were divided into two groups to evaluate (1) the elimination kinetics after 1-microgram and 10-microgram intravitreal injections of cyclosporine and (2) the levels produced after implantation of a device that contained cyclosporine over 6 months. The toxic effects of the intravitreal device over 6 months were assessed in rabbits and cynomolgus monkeys. RESULTS: After the 10-microgram injection, the half-life was longer (10.8 hours vs. 4.2 hours) and the distribution volume was smaller (1.7 mL vs 3.2 mL) than after the 1-microgram injection. This difference can be attributed to saturable partitioning of the drug. The device resulted in a vitreous concentration of approximately 500 ng/mL throughout the study period. In the rabbit it resulted in reversible lens opacification and decreased b-wave amplitude. This toxic effect was not detected in the monkey. CONCLUSIONS: The device produces sustained intravitreal levels of cyclosporine. Although it was associated with reversible toxic effects in the rabbit, it was well tolerated in primates. Sustained-release implants are a promising new treatment for chronic uveitis.