Monitoring high-risk AMD patients may help preserve long-term vision, study says

Close monitoring of high-risk patients with age-related macular degeneration may help detect choroidal neovascular lesions located outside the fovea before any substantial vision loss occurs, a long-term study found.

"Early detection may lead to improved long-term visual acuity," the study authors said in the September issue of Ophthalmology.

Maureen G. Maguire, PhD, and colleagues in the CAPT (Complications of age-related macular degeneration prevention trial) research group evaluated the characteristics of incident CNV that had developed among 282 eyes of 225 patients enrolled in the study.

At baseline, the patients had large, bilateral drusen that were greater than 125 µm in diameter and visual acuity better than 20/40 in both eyes.

One eye of each patient had been randomly assigned to receive low-intensity laser treatment; fellow eyes received no treatment. Subsequently, patients were examined at 6 months and annually thereafter for either 5 or 6 years, depending on enrollment date.

Of the 282 eyes with CNV lesions, 192 lesions (68%) were occult only, 153 lesions (54%) were subfoveal, and 157 lesions (56%) had geographic atrophy of two or less macular photocoagulation study disc areas, the authors noted.

Visual acuity and visual acuity loss were similar in 179 treated and untreated eyes that had received visual acuity measurements at the time of first detection. Among these 179 eyes, 123 eyes (68.7%) had visual acuity of 20/40 or better and 127 eyes (70.9%) had lost less than two lines of vision from baseline.

Bilateral CNV developed in 57 patients (25%), the authors noted.

"Lesions in eyes of bilaterally affected patients were no more similar to each other than affected eyes in two different patients," they said.