[Preoperative factors influencing visual acuity following vitrectomy for exudative age-related macular degeneration]

We investigated the relations between ingrowth site and visual results in patients undergoing surgical removal of subfoveal choroidal neovascular membranes (CNV) caused by age-related macular degeneration (AMD).

The subjects were 70 eyes(69 patients), which underwent surgical removal of CNV for AMD and were followed up for 6 months or more. The eligibility criteria were active subfoveal choroidal neovascular membrane 3 disc diameters (DD) or less in size located above the retinal pigment epithelium, and visual acuity of 0.3 or worse. We analyzed the relationships between postoperative best-corrected visual acuity and preoperative factors: ingrowth site of CNV, distance between the fovea and the CNV edge, CNV size, and fluorescence pattern in indocyanine green angiography (IA).

Patients 1) with feeder vessels located outside the foveal avascular zone (FAZ) rather than inside the FAZ and/or unknown feeder vessels, 2) with a distance between the fovea and the CNV edge 0.2 DD or less than 0.2 DD versus larger, than 0.2 DD 3) with a 1 DD or smaller CNV versus 1.5 DD or larger, and 4) type I, II, or III findings in IA rather than type IV had good postoperative best-corrected visual acuity.

To achieve better postoperative visual acuity after surgical removal of CNV associated with AMD, it is important to select CNV with ingrowth sites outside the FAZ, small and large CNV with a relatively short distance between the fovea and the CNV edge closest to the fovea, and type I, II, and III findings in IA.