By David Douglas
NEW YORK (Reuters Health) Feb 04 - Although one-eye cataract surgery improves vision, including the second eye may yield greater rewards, researchers suggest.
As Dr. Bryan S. Lee told Reuters Health by email, "Bilateral cataract surgery appears to provide a significant benefit beyond unilateral surgery in visual acuity, reading speed, mobility, and self-reported visual functioning."
Dr. Lee of Johns Hopkins School of Medicine, Baltimore, Maryland and colleagues studied 1,739 participants in a prospective, population-based eye study.
Everyone was between 65 and 84 years old at enrollment, with bilateral baseline best-corrected visual acuity (BCVA) logarithm of the minimum angle of resolution (logMAR) no greater than 0.3 (at least 20/40), or cataract surgery during the study period. Over the course of two years, 90 subjects had unilateral cataract surgery and 29 had bilateral surgery.
As reported January 28th online in Ophthalmology, after adjustment for potentially confounding variables, BCVA of logMAR improved by 0.04 in the unilateral group (compared to no surgery) and 0.13 in the bilateral group.
Compared to the no surgery group, reading speed increased by 12 words per minute in the unilateral group and 31 in the bilateral group.
Activities of Daily Vision Scale scores (measuring vision at a distance, close-up, glare, and day and night driving) showed a significant positive change of five points of relative improvement in the bilateral group compared to the no surgery group. In contrast, the unilateral group showed a five-point decline.
After adjusting for age and baseline status, the overall mobility z-score in the unilateral group decreased 0.18 more than in the no surgery group (p= 0.02). In the bilateral group there was a 0.18 z score improvement, which wasn't statistically significant.
The results, say the researchers, indicate the overall benefits of cataract surgery but "also suggest that participants who undergo second-eye surgery are likely to function better than those who undergo only unilateral surgery."
Dr. Lee added that "Even first-eye cataract surgery with an excellent outcome may not have restored maximal function, so we recommend that these patients continue to undergo close follow-up."
Such follow-up, the investigators say, involves asking whether patients are experiencing continued difficulty with contrast sensitivity, reading, mobility, or other visual needs, even if their visual acuity seems to be satisfactory.
Reuters Health Information © 2013