Rate of Macular Ganglion Cell-inner Plexiform Layer Thinning in Glaucomatous Eyes With Vascular Endothelial Growth Factor Inhibition

Purpose: To evaluate the rate of progressive macular ganglion cell-inner plexiform layer (GCIPL) thinning in patients with open-angle glaucoma (OAG) who had been treated with intravitreal antivascular endothelial growth factor (VEGF) injection for wet age-related macular degeneration (AMD). Methods: This study was a retrospective modified case control study with fellow eye comparison. We enrolled bilateral OAG patients who had been treated with repeated anti-VEGF injections for unilateral wet AMD and followed-up on for a minimum of 24 months by Cirrus high-definition optical coherence tomography. The rate of macular GCIPL thinning was determined by linear regression of serial optical coherence tomography GCIPL thickness measurements over time. We compared the rate of macular GCIPL thinning between anti-VEGF-treated eyes and fellow untreated dry AMD eyes. Results: This study involved 32 OAG eyes of 16 subjects. The total follow-up period was 58.4±25.5 (24 to 98) months, and the mean number of anti-VEGF injections was 10.6±10.4 (3 to 40). The eyes with repeated anti-VEGF treatment differed significantly from their fellow eyes in the rate of GCIPL thinning (−2.95±3.58 vs. −0.77±0.95 µm/y, P=0.015). Also, multivariable regression analyses showed that anti-VEGF injection was significantly associated with the rate of GCIPL thinning (P=0.025). Conclusions: In subjects with bilateral OAG, the rate of GCIPL thinning is significantly faster in eyes treated with anti-VEGF injection for wet AMD than in untreated dry AMD fellow eyes. This finding suggests that in glaucomatous eyes, VEGF inhibition could play a role, at least in part, in progressive change of inner retinal layers.