Analysis of the Retinal Nerve Fiber Layer after Indocyanine Green–Assisted Vitrectomy for Idiopathic Macular Holes

Abstract

To analyze retinal nerve fiber layer (RNFL) thickness in eyes with or without visual field (VF) defects after indocyanine green-assisted vitrectomy for idiopathic macular holes using optical coherence tomography (OCT) and to investigate the relationship between postoperative VF defects and RNFL damage. Retrospective interventional case series. Thirty-four eyes of 32 patients with idiopathic macular holes that underwent vitrectomy between January 2001 and March 2003 were included in this study. Eyes were divided into 3 groups according to the occurrence of postoperative VF defects and the use of indocyanine green for internal limiting membrane peeling during surgery: 11 eyes with VF defects after indocyanine green-assisted vitrectomy (group 1), 9 eyes without VF defects despite the use of indocyanine green (group 2), and 14 eyes without VF defects that underwent vitrectomy without indocyanine green (group 3). Retinal nerve fiber layer thickness in each of 4 quadrants (superior, inferior, nasal, temporal) was measured with OCT. Retinal nerve fiber layer thickness around the optic disc. The mean RNFL thickness in 3 of 4 quadrants (superior, nasal, inferior) in group 1 was significantly less than that in the corresponding quadrant in groups 2 and 3 (P<0.01). In the temporal quadrant, there was a significant difference between groups 1 and 3 (P = 0.02), but not between groups 1 and 2. The RNFL thickness in group 1 was significantly less in 3 quadrants in operated eyes than in fellow eyes (P<0.05). The RNFL thickness was reduced in eyes with VF defects after indocyanine green-assisted vitrectomy for macular holes, suggesting that the postoperative VF defects may have been caused by RNFL damage relating to the use of indocyanine green.