Bruch's membrane opening in high myopia and its correlation with axial length

PurposeTo measure the Bruch's Membrane Opening (BMO) area and Minimum Rim Width (BMO-MRW) in eyes with high myopia and correlate it with axial length (AL).MethodsA cross-sectional, hospital-based study of 40 participants with high myopia Spherical Equivalent Refraction (SER) ≤ -6D was conducted. Spectral Domain-Optical Coherence Tomography (SD-OCT) of both the eyes (BE) was performed using Glaucoma Module Premiere Edition (GMPE) with Anatomic Positioning System (APS) to measure BMO area and BMO-MRW. The AL in myopic patients was measured using Partial Coherence Interferometry (IOL Master).ResultsThis study included 80 eyes of 40 participants aged 18-35 years. The mean BMO area was 2.28 ± 0.48 mm² in the right eye (RE) and 2.15 ± 0.59 mm² in the left eye (LE) and was significantly correlated with (AL). A statistically significant positive correlation was observed between the BMO area and AL in (BE) (RE: r = 0.465, p = 0.003; LE: r = 0.374, p = 0.029). Likewise, the mean BMO-MRW was RE: 325.69 ± 96 μm; LE: 339.20 ± 79.50 μm. In the RE group, there was a significant negative correlation between the inferior temporal (r = - 0.353, p = 0.027) and inferior nasal quadrants (r = - 0.424, p = 0.007) of the BMO-MRW and AL, whereas in the LE group, all the BMO-MRW quadrants were negatively correlated (p < 0.05) with AL. No significant differences were found between the RE and LE when comparing the means of the refractive error (p = 0.314), AL (p = 0.212), BMO area (p = 0.35), and BMO-MRW (p = 0.819).ConclusionThe findings revealed that BMO area increases and BMO-MRW thickness decreases with increasing AL in high myopic eyes and may contribute to structural vulnerability of the optic nerve head, potentially increasing the risk of glaucomatous damage.