RELATION OF THE FUNCTIONAL AND STRUCTURAL FUNDUS CHANGES AFTER SUBMACULAR SURGERY FOR NEOVASCULAR AGE-RELATED MACULAR DEGENERATION

Aims-This study was carried out to investigate the precise pattern of visual loss associated with subfoveal choroidal neovascular membranes and the mechanism by which vision is stabilised or improved after subm acular surgery. Methods-Preoperative and postoperative quantitative mi croperimetry using the scanning laser ophthalmoscope was performed on six eyes of five patients with age-related macular degeneration who un derwent subfoveal choroidal neovascular membrane excision. The relatio n of the microperimetry findings to the preoperative and postoperative fluorescein angiographic features was also assessed. Results-Four of the six eyes had visual improvement by the 6 month postoperative visit ; the other two had stabilisation of vision at the preoperative level. Despite these beneficial visual effects, none of the patients fixated within the bed of the excised choroidal neovascular membrane. Subfove al choroidal membrane excision was associated with a 36% average incre ase in the absolute scotoma at the 1 month postoperative visit, compar ed with the preoperative size. The postoperative scotoma appeared to r emain stable or decreased slightly in size between the 6 month and 1 y ear postoperative visits. Recovery of vision was associated with the d evelopment of a more stable preferred eccentric fixation locus, of whi ch the distance from the centre of the foveal avascular zone was relat ed to final postoperative vision. Most of the eccentric fixation loci were inferotemporal to the bed of the excised choroidal neovascular me mbrane. The surgical retinotomy site was associated with persistent po stoperative relative scotoma in five of the six cases, but resolved in one patient after 1 year.Conclusion-These findings indicate that quan titative scanning laser ophthalmoscope microperimetry may aid in the s urgical planning of subfoveal choroidal neovascular membrane excision.