The effect of nimodipine, a centrally active calcium antagonist, on visual function and mascular blood flow in patients with normal-tension glaucoma and control subjects.

PURPOSE: This study was performed to evaluate the effect of nimodipine, a centrally active calcium channel antagonist on automated Humphrey visual fields, Farnsworth-Munsell 100 (FM-100) hue color vision testing, and macular blood flow (blue field entoptic simulation technique) in patients with normal-tension glaucoma (NTG) and control subjects. METHODS: Thirteen patients with NTG and thirteen age- and sex-matched control subjects were studied in a prospective, placebo-controlled, double-masked, crossover protocol. On each of the two study dates, testing was performed at baseline and 90 minutes after administration of either two 30-mg nimodipine capsules or two identical appearing placebo capsules. Blood pressure and pulse were monitored throughout the study. RESULTS: Nimodipine administration resulted in a performance corrected improvement in Humphrey visual field mean deviation (patients with NTG and control subjects), corrected pattern standard deviation (patients with NTG), and macular sensitivity (the average of the foveal threshold and the four most central points of the visual field; patients with NTG). The FM-100 hue error scores significantly decreased after administration of nimodipine in patients with NTG and control subjects compared with baseline. There were no significant differences in baseline leukocyte velocity or density between patients with NTG and control subjects; no significant changes in leukocyte velocity or density were noted after administration of nimodipine in either group. CONCLUSION: Nimodipine caused a significant performance corrected improvement in visual field testing and a significant improvement in color vision. Nimodipine did not alter macular hemodynamics as measured using the blue field entoptic simulation technique, although results were hampered by high variability, particularly in the leukocyte density measurements.

A model of the incidence and consequences of choroidal neovascularization secondary to age-related macular degeneration. Comparative effects of current treatment and potential prophylaxis on visual outcomes in high-risk patients.

OBJECTIVE: To describe the comparative impact of current and preventive treatments on incidence of choroidal neovascularization (CNV) and severe vision loss in patients with bilateral soft drusen (BSD). DESIGN: Stochastic model. SETTING: US population. PATIENTS: Prevalence cohort of white patients 43 years or older with BSD. INTERVENTIONS: Application of prophylaxis of 10% to 50% efficacy to 1 or both eyes of patients with BSD, application of laser photocoagulation to eligible CNV lesions, or both. MAIN OUTCOME MEASURES: Proportion of patients with BSD after 10 years with unilateral and bilateral CNV and resultant unilateral and bilateral vision loss to visual acuity of 20/200 or worse. RESULTS: The natural history of patients with BSD generated by the model shows that 12.40% of these patients develop either unilateral or bilateral CNV within 10 years of their entry into the BSD prevalence cohort. Bilateral disease occurs in 3.86% of patients with BSD within 10 years. The proportion of patients with BSD becoming legally blind from CNV within 10 years is 2.54% if no treatment is performed. Current laser treatment for CNV decreases the proportion with legal blindness within 10 years to 2.24%. The addition of a preventive treatment of 10% efficacy applied bilaterally to the current laser treatment regimen decreases the proportion with legal blindness to 1.86%; a 25% effective preventive treatment decreases it to 1.34%. Comparatively, preventive treatment of 10% and 25% efficacy given to the fellow eye only after the first eye has developed CNV decreases the proportion of legally blind patients at 10 years only to 2.06% and 1.77%, respectively. All outcomes vary with sex and age at entry into the BSD cohort. CONCLUSIONS: Patients with BSD face a 12.40% risk of developing CNV within 10 years. The addition of even a modest (10% effective) bilateral preventive treatment to the current regimen for CNV would more than double the prevention of legal blindness in the BSD population relative to current laser treatment; a preventive treatment of 33% efficacy more than halves the rate of legal blindness caused by CNV. Preventive treatment given to the fellow eye only after the first develops CNV has substantially less impact.