Consistency of Bruch Membrane Opening Detection as Determined by Optical Coherence Tomography.

PURPOSE: To investigate the consistency of Bruch membrane opening (BMO) detection as determined by Cirrus high-definition optical coherence tomography (OCT).

MATERIALS AND METHODS: This study enrolled 106 healthy eyes and 194 glaucomatous eyes who underwent OCT examinations. The location of BMO was evaluated by inspecting 72 cross-sectional optic nerve head (ONH) images (5 degrees intervals for 360 degrees) per eye in which BMO location is automatically detected by the OCT algorithm. The consistency of BMO detection was investigated by comparing consecutive cross-sectional ONH images. If the location of the BMO margin did not agree between images, it was considered as inconsistent BMO detection.

RESULTS: Among 300 eyes, 21 (7.0%) showed inconsistent BMO detection. Inconsistency in BMO detection was associated with a higher degree of myopia (P<0.001). All inconsistent BMO detection was found in areas with β-zone peripapillary atrophy. Eyes with inconsistent BMO detection showed greater changes in ONH parameters and retinal nerve fiber layer thickness than eyes with consistent BMO detection (P<0.001).

CONCLUSIONS: Although BMO locations were consistent in most cases, in some cases, there were inconsistencies in BMO locations determined by OCT, especially in myopic eyes with peripapillary atrophy. Inconsistency in BMO detection resulted in changes in ONH parameters and retinal nerve fiber layer thickness. These finding should be considered when assessing glaucoma by using OCT.