Abstract
Abstract: :
Purpose:To evaluate a technique for objectively identifying alternative EVLs in patients with age-related macular degeneration. To compare the results of reading rehabilitation at clinically defined loci to those identified by the new experimental methods. Methods:A clinically defined EVL was determined based on traditional low vision assessment methods including fundus photographs of current fixation, Humphrey visual fields, and Lighthouse visual acuities. To determine an experimentally defined EVL, local visual acuity perimetry was compared to electrophysiological perimetry obtained using the multifocal electroretinogram (VERIS). Eight patients were randomized to be trained at either their clinical or experimental EVL. Reading rehabilitation consisted of an 8-week program focused on the visual skills involved in reading. Pre- and post-training assessments were performed using standardized reading batteries and an orientation and mobility assessment previously validated in our laboratory. Results:Reading performance improved on all standardized measures following training. For example, accuracy on the Pepper Visual Skills for Reading Test showed improvement in both groups; the experimental group showed a higher percentage of improvement (12%) compared to the clinical group (2%). The reading portion of the O&M assessment also showed improvement in both groups; the experimental group showed a higher percentage of patients having improved (52%) compared to the clinical group (43%). In contrast, the clinically defined EVL group showed a greater number of patients showing improvement (31%) on the mobility portion of the O&M assessment than the experimentally defined group (17%). Conclusion:Consistent with previous studies, these data demonstrate that the optimal EVL may depend on the task. In our work, reading rehabilitation training at experimentally defined EVLs may result in better reading outcomes. However, the clinically defined EVLs may result in better outcomes for mobility tasks.
Keywords: 459 low vision • 308 age-related macular degeneration • 539 reading