Radial optic neurotomy for central retinal vein occlusion: a retrospective pilot study of 11 consecutive cases.

PURPOSE: Retinal vascular occlusive disease is the second leading cause of permanent retinal blindness. The etiology of central retinal vein occlusion (CRVO) is not well understood. The anatomy of the optic disk including the cribriform plate and scleral ring may contribute to the development of retinal vaso-oclussive diseases. Neurovascular compression within the confined space at this location may play a pathoetiologic role in CRVO. The authors performed radial optic neurotomy in patients with CRVO to relax this space and relieve pressure on the central retinal vein. METHODS: Radial optic neurotomy (RON) was performed on 11 consecutive patients with severe, hemorrhagic CRVO with visual acuities of 20/400 or less. A microvitreoretinal blade was used to relax the scleral ring, cribriform plate, and adjacent sclera of the optic disk. Reperfusion of the retina was achieved via decompressing the central retinal vein. RESULTS: Radial optic neurotomy was performed successfully in all 11 patients. There were no complications noted with this procedure. All patients had clinical improvement as determined by fundus examination, photography, and fluorescein angiography. Postoperative visual acuities were equal or improved in 82% of patients. Eight of the patients (73%) had rapid improvement of visual acuity with an average gain of five lines of vision. CONCLUSIONS: Surgical decompression of CRVO via RON is a technically feasible and initially safe procedure that is associated with rapid reperfusion of the retina. Resolution of the intraretinal hemorrhage, edema, and ischemia may improve the visual prognosis in patients with this common retinal disorder.

Long-term results of laser treatment in the ocular histoplasmosis syndrome.

OBJECTIVE: To determine the long-term visual outcome, rate of persistent choroidal neovascularization, and rate of recurrent choroidal neovascularization in eyes undergoing laser photocoagulation for choroidal neovascularization secondary to ocular histoplasmosis syndrome. DESIGN AND PATIENTS: One hundred one eyes with 5 to 16 years of follow-up that presented with choroidal neovascularization secondary to ocular histoplasmosis were retrospectively evaluated. Patients were grouped according to location of choroidal neovascularization and assignment to observation or laser photocoagulation. MAIN OUTCOME MEASURES: Visual acuity outcome and loss for all groups were compared. The rates of persistent and recurrent choroidal neovascularization for the treated eyes were also evaluated. RESULTS: Visual acuity of 20/40 or better was obtained in 71% of eyes with treated extrafoveal choroidal neovascularization and 68% with treated juxtafoveal choroidal neovascularization. Recurrent choroidal neovascularization was observed in 23% of treated eyes during a mean follow-up of 9.6 years. CONCLUSION: Results support the long-term benefit of photocoagulation and need for careful follow-up.

A bidirectional, turbulent, delaying, centripetal, suction filter.

The physiologic functions of the outer retina and the pathophysiology of drusen-related macular failure are best explained by attributing the properties of a bidirectional, turbulent, delaying, centripetal, suction filter to Bruch's membrane.