Topographic localization of macular retinal ganglion cell loss associated with localized peripapillary retinal nerve fiber layer defect

Abstract

Purpose: To investigate the topographic relationship between ganglion cell-inner plexiform layer (GCIPL) and peripapillary retinal nerve fiber layer (pRNFL) defects in open-angle glaucoma patients with localized RNFL defects, using spectral-domain optical coherence tomography (SD-OCT).

Methods: We analyzed 140 eyes of 140 patients showing a localized RNFL defect in one hemifield, the angular width of which was limited to one clock-hour sector. The RNFL and macular GCIPL scans were obtained using SD-OCT. The clock-hour location and width of pRNFL defects on the RNFL deviation map were determined, and their topographic association with corresponding GCIPL defects on the GCIPL deviation map was assessed.

Results: A "GCIPL deviation frequency map" demonstrating GCIPL defects corresponding to six different clock-hour locations of pRNFL defects was obtained, and it revealed the following specifics: (1) pRNFL defect at 12, 11, and 10 o'clock corresponded to GCIPL defect in the superior macula, as those at 8, 7, and 6 o'clock did to those in the inferior macula; (2) the overall GCIPL defect had an arcuate shape that appeared as a continuation of the pRNFL defect; (3) the temporal macular region was the frequently damaged site in either hemifield, and was larger in the inferior hemifield than in the superior hemifield. Additionally, an interindividual variability of GCIPL defect was noted for patients with the same clock-hour location of pRNFL defect.

Conclusions: The GCIPL deviation frequency map demonstrating the topographic relationship between pRNFL and GCIPL defects was generated using SD-OCT. Our results indicated the topographic location of retinal ganglion cell death associated with clock-hour location of pRNFL loss in vivo.

Keywords: ganglion cell-inner plexiform layer defect; peripapillary retinal nerve fiber layer defect; spectral-domain optical coherence tomography; topographic relationship.