CHANGE IN RETINAL SENSITIVITY DUE TO EXCISION OF CHOROIDAL NEOVASCULARIZATION AND ITS INFLUENCE ON VISUAL ACUITY OUTCOME

Abstract

Excision of choroidal neovascular membranes (CNV) has been attempted as an alternative to photocoagulation for the management of subfoveal CNV. To evaluate functional results of CNV excision, we studied retinal sensitivity in the area corresponding to the CNV (CNV area). Static microperimetry using a scanning laser ophthalmoscope was performed on 17 eyes before and after CNV excision. We studied whether CNV excision changed retinal sensitivity in the CNV area. To evaluate the relationship between retinal sensitivity and visual acuity, further testing was performed on nine patients who had subfoveal CNV from age-related macular degeneration (ARMD). Preoperatively, 5 of 17 eyes (29.4%) had retinal sensitivity in the CNV area. Postoperatively, 4 of 17 (23.5%) eyes had retinal sensitivity. Surgery did not significantly change retinal sensitivity in the CNV area (P > 0.999). There was a significant correlation between the presence of retinal sensitivity and visual acuity. Postoperative visual acuity of eyes with retinal sensitivity in the CNV area was better than that of the eyes without sensitivity in the patients with subfoveal CNV from ARMD (P - 0.0017). In most cases, excision of CNV does not improve central retinal sensitivity, and patients have poor visual outcome. In some cases, however, postoperative sensitivity in the bed of CNV is preserved and visual outcome is relatively good. Better or worse preoperative retinal sensitivity does not predict better or worse visual acuity outcome, respectively.