Visual Performance of Patients With AMD Using Wavefront-Guided Lenses

Abstract

Purpose:: To determine if high-order aberration correction using wavefront-guided spectacle lenses impacts reading performance in patients with age-related macular degeneration (AMD).

Methods:: We recruited 16 patients (7 females, 9 males; mean age = 72.6 years) with a diagnosis of AMD. The mean visual acuity of the better eye for the patients was 20/145. Patients were provided with a pair of lenses that provided a near refraction determined by traditional methods, and another pair that provided for a near refraction and lower and higher order wavefront-aberration correction (iZon). A double masked cross-over design was used. The patients used one pair of lenses for one week, then were assessed for visual performance, and then were given the second pair of lenses to wear for the next week, which was followed by a second assessment. The order of lenses was randomized. Patients’ reading rate (words per minute), critical print size, and reading acuity were assessed using the MNRead Acuity Charts. A View Sentences test (done at 90% and 10% text contrast) was used to assess the patients’ reading speed and accuracy by presenting two lines of text on a monitor.

Results:: There was a significant difference in the mean reading speed on the MNRead Charts between the two lens conditions (paired t = -3.8, p<0.002). Patients read faster with the iZon lenses (Mean speed = 149.02 wpm) compared to the traditional lenses (Mean speed = 121.40 wpm). Eleven patients preferred the iZon lenses, compared to 5 patients who preferred the standard lenses. Patients showed a 7.4 + 2.8% increase in reading speed for View Sentences at 90% contrast using the iZon lenses compared to the standard lenses, and a 22.0 + 4.6 % increase at 10% contrast.

Conclusions:: The iZon lenses showed a functional advantage especially under conditions of lower contrast.

Keywords: age-related macular degeneration • optical properties • reading