João Heitor Marques, Ana Sofia Martins, Pedro Baptista, Bernardete Pessoa, João Melo Beirão
The geometry of the posterior segment differs substantially, independently of AL and age. A rounder posterior segment is associated with RRD, while a steeper curvature is associated with MH, suggesting that globe shape dictates whether vitreoretinal traction manifests peripherally or centrally. rBM on OCT is a simple and reproducible measure that may serve as a risk factor for vitreoretinal disease.
PURPOSE: To create an algorithm to calculate the posterior radius of curvature of Bruch´s membrane (rBM) on regular optical coherence tomography (OCT) and determine the association between posterior segment shape and vitreoretinal disease.
METHODS: Retrospective cross-sectional study that included patients with macular hole (MH) or rhegmatogenous retinal detachment (RRD). RRD eyes were matched with MH eyes based on age and axial length (AL), resulting in a final analysis of 43 eyes in each group. OCT B-scans were processed using a custom but open algorithm to calculate the rBM.
RESULTS: rBM was significantly higher in the RRD group (mean 56.1 mm, 95%CI 46.2 - 66.1 mm) whereas the MH group exhibited a steeper curvature (mean 41.6 mm, 95%CI 37.4 - 45.9 mm). No relationship was observed between AL and rBM. Multivariate logistic regression confirmed the independent effect of rBM.
CONCLUSION: The geometry of the posterior segment differs substantially, independently of AL and age. A rounder posterior segment is associated with RRD, while a steeper curvature is associated with MH, suggesting that globe shape dictates whether vitreoretinal traction manifests peripherally or centrally. rBM on OCT is a simple and reproducible measure that may serve as a risk factor for vitreoretinal disease.