Preferential hyperacuity perimeter as a functional tool for monitoring exudative age-related macular degeneration in patients treated by intravitreal ranibizumab

Abstract

Purpose: To analyze the response to anti vascular endothelial growth factor (VEGF) treatment for exudative age-related macular degeneration (AMD), with respect to changes in the Preferential Hyperacuity Perimeter (PHP), best-corrected visual acuity (BCVA), and spectral-domain optical coherence tomography (SD-OCT), and to investigate whether the PHP score predicts the need for reinjection.

Methods: Consecutive patients with newly diagnosed exudative AMD underwent the PHP metamorphopsia test, BCVA, and SD-OCT at five time points after initiation of ranibizumab therapy (0.05 mL/0.5 mg). At the third and sixth months, reevaluation for additional injections was done. The relationships between PHP, BCVA, and SD-OCT parameters over time as well as their ability to predict the need for reinjection were examined.

Results: Analysis included 17 eyes (17 patients, 70% females; mean age, 83.2 years). The mean PHP metamorphopsia test score improved from 25.6 ± 41 (baseline) to 10.7 ± 20.1 (P < 0.05) over 6 months, after a mean of 4.2 (±1.0) injections. Mean reduction in SD-OCT parameters well reflected the functional improvements as evaluated by PHP (Spearman correlation = 0.9, P < 0.05). Mean BCVA did not improve over 6 months (0.6 vs. 0.58 logMAR), and neither correlated with SD-OCT morphologic changes (Spearman correlation = 0.1, P > 0.05) nor with PHP functional changes (Spearman correlation = 0.1, P > 0.05). The PHP predicted the need for reinjection with an accuracy of 75% (sensitivity, 83 ± 12%; specificity, 67 ± 15%), whereas a combination of all the measurements (PHP, BCVA, and SD-OCT) yielded an accuracy of 87% (sensitivity, 83 ± 12%; specificity, 90 ± 10%).

Conclusions: Improvement in the metamorphopsia test score after intravitreal injections of ranibizumab, as well as its ability to predict the need for retreatment, suggest that PHP may be used to monitor response to anti-VEGF therapy in patients with exudative AMD.