Bilateral ocular neuromyotonia: oculographic correlations.

We observed bilateral ocular neuromyotonia in a 45-year-old woman previously treated for a pituitary adenoma. She experienced episodic diplopia attributable to dysfunction of muscles innervated by both oculomotor nerves. Oculography demonstrated episodes of tonic adduction with slowing and restriction of saccades in all directions, but no oscillatory component. A combination of impaired phasic firing in agonist muscles and tonic contraction of antagonist muscles explains the paroxysms of eye movement limitation in this disorder.

The relationship of anticipatory smooth eye movement to smooth pursuit initiation.

We measured anticipatory smooth eye movements and smooth pursuit initiation with predictable and unpredictable step-ramp stimuli in normal subjects. Subjects generated anticipatory eye motion before targets moved and during intervals when targets suddenly disappeared. Expectations of target trajectory modified pursuit acceleration and latency, demonstrating that pursuit initiation is not governed by visual inputs alone. Anticipatory smooth eye movements and predictive contributions to smooth pursuit had similar accelerations and velocities. Anticipation and pursuit initiation varied in parallel between subjects; anticipation was stronger in subjects who generated faster smooth pursuit. These findings imply that anticipatory and smooth pursuit eye movements are governed by a common mechanism.

Prostaglandin E2 and protein release following Nd:YAG laser application to the anterior capsule of rabbit lens.

We compared the effects of Nd:YAG laser anterior capsulotomy and photophacofragmentation on the release of prostaglandin E2 (PGE2) and protein in the New Zealand rabbit aqueous humor. Following anterior capsulotomy, the concentration of PGE2 was significantly more elevated (P less than .025) than it was in the contralateral untreated eyes at intervals from one-half hour up to four hours, and rapidly decreased in 24 hours. The concentration of protein showed a relatively gradual increase which became significant (P less than .05) after two hours, and remained elevated 24 hours after anterior capsulotomy. In contrast, photodisruption into the lens without damaging the anterior capsule showed little effect on the release of PGE2 and protein in the aqueous humor.

Randomized clinical trial of intraocular silicone vs. gas in the management of complicated retinal detachment and vitreous hemorrhage.

We performed a prospective randomized clinical study to compare intravitreal silicone oil vs. gas (20% C3F8 or 30% C4F8) in the management of complicated retinal detachments and vitreous hemorrhage. Despite similar anatomic and visual results, the gas-treated group had significantly more instances of vitreous hemorrhage, late elevated intraocular pressure, and localized retinal detachment as postoperative complications than those receiving oil injections (P less than .05). Silicone oil injections containing less than 3.0 ml contributed significantly to postoperative detachments (P less than .05).

Use of crossed-linked hyaluronic acid in the anterior segment.

We evaluated the use of cross-linked hyaluronic acid (CLHA) in the anterior segment of the rabbit's eye. Subconjunctival injection of less than 0.1 ml of CLHA was well tolerated. Intracameral injection containing more than 0.05 ml of CLHA produced severe inflammatory reaction.

Retinal toxicity of ganciclovir in vitrectomy infusion solution.

The authors investigated the retinal toxicity of the antiviral agent ganciclovir after its addition to vitrectomy infusion fluid in rabbit eyes. Intravitreal infusion of the drug in concentrations up to 30 micrograms/ml produced no electroretinographic or histologic changes suggestive of retinal toxicity. Ganciclovir in vitrectomy infusion fluid has potential therapeutic benefit in viral retinitis (particularly in cytomegalovirus retinitis) associated with vitreous traction or rhegmatogenous retinal detachment. Based on the median inhibitory doses of ganciclovir against various herpes group viruses and the results of this study, a concentration of 30 micrograms/ml or less of the drug is recommended for vitrectomy infusion solution.

Early anterior segment complications after silicone oil injection.

We analyzed retrospectively 45 patients who had received silicone oil injection for vitreoretinal problems and divided them into three groups: aphakic patients who had undergone an extracapsular cataract extraction (AEC), aphakic patients who had undergone an intracapsular cataract extraction (AIC) and phakic patients (PHA). Patients were followed up from 4 to 13 months (average: 8.5 months). Irreversible silicone keratopathy was found in 50% of the eyes in the AIC group between 4 and 8 weeks postoperatively. An intact lens or capsule correlated well with the absence of this complication. In phakic eyes, secondary cataract was the most prominent early complication, developing by the end of the eighth week in 60% of eyes. Other early complications were inflammatory surface silicone membranes, rubeosis, iritis, glaucoma and capsular opacification.

Penetrating diathermy for retinal microincarceration in the management of giant retinal tears with inverted flaps.

Using vitrectomy, fluid-air exchange, penetrating diathermy, and scleral buckling, surgical success was achieved in 24 of 27 eyes with inverted giant retinal tears (GRTs) and concomitant unfavorable conditions. The follow-up period ranged from 6-52 months. Anatomic success was achieved in 18 eyes. Tears larger than 300 degrees with immobile flaps or advanced proliferative vitreoretinopathy (PVR) contributed significantly to surgical failure (P less than .05). Preoperative (greater than C2) and postoperative PVR figured significantly in unimproved final visual acuity (P less than .05). Penetrating diathermy was effective in fixating the repositioned retina, with little complication. Postoperative therapy with fluid-gas or air exchange or photocoagulation greatly enhanced final success.