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Beyond axial length: posterior segment curvature determining vitreoretinal traction
João Heitor Marques1,2, Ana Sofia Martins1, Pedro Baptista1,2
1Ophthalmology Department, Centro Hospitalar Universitário de Santo António, Portugal.
Retina (Philadelphia, Pa.)
|August 7, 2026
Summary
A rounder posterior segment is linked to rhegmatogenous retinal detachment (RRD), while a steeper curvature is associated with macular holes (MH). Posterior segment shape, measured by the radius of curvature of Bruch´s membrane (rBM), may predict vitreoretinal disease risk.
Area of Science:
- Ophthalmology
- Biomedical Engineering
- Medical Imaging
Background:
- The posterior segment's geometry influences vitreoretinal diseases.
- Quantifying posterior segment shape is crucial for understanding disease pathogenesis.
- Optical coherence tomography (OCT) offers high-resolution imaging of the posterior segment.
Purpose of the Study:
- To develop an algorithm for calculating the posterior radius of curvature of Bruch´s membrane (rBM) using OCT.
- To investigate the association between rBM and vitreoretinal diseases like macular hole (MH) and rhegmatogenous retinal detachment (RRD).
Main Methods:
- Retrospective cross-sectional study including 43 eyes with MH and 43 matched eyes with RRD.
- A custom, open-source algorithm processed OCT B-scans to determine rBM.
- Eyes were matched based on age and axial length (AL).
Main Results:
- The RRD group had a significantly higher rBM (rounder posterior segment) compared to the MH group (steeper curvature).
- No correlation was found between axial length (AL) and rBM.
- Multivariate logistic regression confirmed rBM as an independent factor.
Conclusions:
- Posterior segment geometry varies significantly and independently of AL and age.
- A rounder shape is associated with RRD, and a steeper shape with MH.
- rBM is a reproducible OCT-derived metric that may serve as a risk factor for vitreoretinal disease.
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