Abstract
Abstract: :
Purpose:To evaluate the effect of a centrally acting calcium channel blocker on ocular blood flow and visual function in non-exudative age related macular degeneration (AMD) patients. Methods:Seventeen patients (age 71.1 ± 6.8 years) were examined at baseline and after 1 day, 21 days, and 42 days of 2 mg nilvadipine PO BID. Flow velocity in the ophthalmic artery (OA), short posterior ciliary arteries (PCA), and central retinal artery (CRA) were measured by color Doppler imaging (CDI). Peak systolic (PSV) and end diastolic (EDV) velocities were measured, and Pourcelot's resistive index (RI) was calculated. Visual acuity (VA) was measured using an ETDRS logMAR chart. Post-medication measurements were compared to baseline using Wilcoxon signed ranked paired comparisons. Linear regression was used to assess the correlation between changes in blood flow and changes in VA. Results:ANOVA found no statistically significant changes in CDI or VA measurements. VA significantly correlated with nasal PCA EDV OS and PSV OS at 21 days (p ≤ 0.033, r2 = 0.91), and RI at 42 days (p = 0.011, r2 = -0.999). Conclusion:In non-exudative AMD subjects treated with nilvadipine for 21 days, improvements in nasal PCA blood flow were associated with reduced visual acuity. Similarly, after 42 days treatment, reduced resistance to flow in the nasal PCA was associated with reduced visual acuity.
Keywords: 308 age-related macular degeneration • 514 pharmacology • 620 visual acuity