Cataract surgery does not appear to worsen the course of age-related macular degeneration (AMD), a progressive loss of vision due to deterioration of nerve tissue in the retina, a new study shows.
The finding, however, does not yet settle the long-standing controversy over the appropriateness of cataract surgery in eyes with this disorder, an editorial warns. AMD is the most common cause of blindness in adults 55 years of age and older.
In the latest issue of the Archives of Ophthalmology, Dr. Neil M. Bressler from Johns Hopkins University School of Medicine, Baltimore, and colleagues describe the outcomes of cataract surgery performed on 86 eyes with AMD from 86 elderly patients.
One week after surgery, imaging showed new AMD lesions in 5 eyes, but the authors believe these lesions were present before surgery; they just weren't visible. By month 12, new lesions had been diagnosed in 3 additional eyes.
After excluding deaths, eyes with missing or poor images, and the 5 eyes that probably had AMD before surgery, the AMD progression rate from week 1 to month 12 was less than 5 percent (3 of 65 eyes).
This rate was not significantly different from the rate in the subjects' unoperated eyes; only one (3.3 percent) developed new AMD lesions during the same period.Dr. Barbara E. K. Klein from the University of Wisconsin, the author of the editorial, points out that several studies since the late 1980s have indicated an association between cataract surgery and AMD progression.
In light of inconsistencies in these studies, Klein advises, a "straightforward discussion" between the patient and his or her doctor regarding risks of progression of early AMD and development of late AMD and its accompanying risk of vision loss after cataract surgery. Having this discussion will help "both the patient and his or her physician to make a more informed decision," Klein wrote.