Myopic macular Bruch's membrane defects

Songhomitra Panda-Jonas; Gerd U Auffarth; Jost B Jonas; Rahul A Jonas

doi:10.1016/j.heliyon.2023.e13257

Myopic macular Bruch's membrane defects

Heliyon. 2023 Jan 25;9(2):e13257. doi: 10.1016/j.heliyon.2023.e13257. eCollection 2023 Feb.

Authors

Songhomitra Panda-Jonas^{1

2}, Gerd U Auffarth¹, Jost B Jonas^{1

3

4}, Rahul A Jonas⁵

Affiliations

¹ Department of Ophthalmology, University of Heidelberg, 69120 Heidelberg, Germany.
² Privatpraxis Prof Jonas und Dr Panda-Jonas, Heidelberg, Germany.
³ Department of Ophthalmology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany.
⁴ Institute of Molecular and Clinical Ophthalmology Basel, Switzerland.
⁵ Department of Ophthalmology, University Hospital of Cologne, Cologne, Germany.

Abstract

Purpose: To examine histologic characteristics of macular Bruchś membrane defects (BMD) in axially elongated eyes.

Design: Histomorphometric study.

Methods: Using light microscopy, we examined enucleated human globes for BMDs.

Results: In 247 eyes, BMDs were detected in 15 (6.1%) eyes (axial length:27.0-36.0 mm), in 10 of them in the macular region. Prevalence and size of BMDs (mean:1.93 ± 1.62 mm; range:0.22mm-6.24 mm) correlated with longer axial length (OR:1.52; 95%CI:1.19,1.94; P = 0.001) and higher prevalence of scleral staphylomas (OR:16.3; 95%CI:2.67,99.3; P < 0.001). The BMDs were smaller than corresponding gaps in the retinal pigment epithelium (RPE) (1.93 ± 1.62 mm versus 2.61 mm ± 1.73 mm; P = 0.003), and larger than corresponding gaps in the inner nuclear layer (0.43 ± 0.76 mm; P = 0.008) and inner limiting membrane bridges (0.13 ± 0.33 mm; P = 0.001). Choriocapillaris thickness, BM thickness and RPE cell density did not vary (all P > 0.05) between the BDM border and adjacent areas. In the BMD, choriocapillaris and RPE were absent. The sclera was thinner in the BDM area than in adjacent areas (0.28 ± 0.19 mm versus 0.36 ± 0.13 mm; P = 0.006).

Conclusions: BMDs as hallmarks of myopic macular degeneration are characterized by longer gaps in the RPE and smaller gaps in the outer nuclear layer and inner nuclear layer, by localized scleral thinning, and by a spatial association with scleral staphylomas. Thickness of the choriocapillaris and density of the RPE cell layer, both absent within the BDMs, do not vary between the BMD border and adjacent regions. The results suggest an association between BDMs and absolute scotomas, stretching of the adjacent retinal nerve fiver layer, and an axial elongation-associated stretching effect on BM as etiology of the BDMs.

Keywords: Axial myopia; Bruch’s membrane; Bruch’s membrane defects; Myopia; Myopic macular degeneration; Myopic maculopathy.