Scanning laser ophthalmoscope microperimetric assessment in patients with successful laser treatment for juxtafoveal choroidal neovascularization.

PURPOSE

To evaluate fixation stability and changes in retinal function in patients with laser scar expansion after successful macular photocoagulation for juxtafoveal choroidal neovascularization (CNV).

METHODS

A consecutive series of 35 patients was examined in this prospective study. Only patients who had been successfully treated with laser photocoagulation for juxtafoveal CNV and who could be followed over a period of at least 6 months were enrolled. Fixation stability and localized light sensitivity were examined by microperimetry using a scanning laser ophthalmoscope. Visual acuity was measured 2 weeks and 3 and 6 months after the laser treatment. The correlation between changes in the logarithm of the minimum angle of resolution (LogMAR) visual acuity and the distance between fixation and the center of the fovea was evaluated.

RESULTS

Of 22 eyes of 20 patients that underwent data analysis, laser scar expansion was observed in 16 (72.7%). Ten (62.5%) of the 16 eyes had relative scotomas corresponding to the expanded laser scars. Mean laser scar expansion ratio was 28.7% in the ARMD group and 109.2% in the myopia group, a statistically significant difference (P < 0.01). The change in LogMAR visual acuity was significantly correlated with the distance of fixation locus from the center of the fovea (r = 0.76).

CONCLUSIONS

Laser scars produced by photocoagulation for juxtafoveal CNV may expand and extend into the fovea, causing secondary retinal dysfunction. Scanning laser ophthalmoscopic assessment may be useful in evaluating fixation stability and subclinical changes in retinal function surrounding the laser scars before visual disturbance appears.