Novel Bruch's Membrane Opening Minimum Rim Area Equalizes Disc Size Dependency and Offers High Diagnostic Power for Glaucoma

• Published in: Investigative ophthalmology & visual science Vol. 57; no. 15; pp. 6596 - 6603
• Main Authors: Enders, Philip, Adler, Werner, Schaub, Friederike, Hermann, Manuel M, Dietlein, Thomas, Cursiefen, Claus, Heindl, Ludwig M
• Format: Journal Article
• Language: English
• Published: United States 01-12-2016
• Subjects: Adolescent; Adult; Aged; Aged, 80 and over; Bruch Membrane - diagnostic imaging; Child; Child, Preschool; Cross-Sectional Studies; Female; Glaucoma, Open-Angle - diagnosis; Glaucoma, Open-Angle - physiopathology; Humans; Intraocular Pressure; Male; Middle Aged; Nerve Fibers - pathology; Ocular Hypertension - diagnosis; Ocular Hypertension - physiopathology; Optic Disk - pathology; Retinal Ganglion Cells - pathology; Retrospective Studies; Tomography, Optical Coherence - methods; Visual Fields - physiology; Young Adult
• ISSN: 1552-5783; 1552-5783
• DOI: 10.1167/iovs.16-20561

The purpose of this study was to assess the diagnostic power of the novel two-dimensional parameter Bruch's membrane opening minimal rim area (BMO-MRA) in spectral-domain optical coherence tomography (SD-OCT) for detection of glaucoma compared to minimal rim width (BMO-MRW) and retinal nerve fiber layer (RNFL) thickness in large and small optic discs.
In this case-control, cross-sectional study, 207 eyes of 207 participants, including 89 controls and 97 patients with glaucoma and 21 with ocular hypertension (OHT), with a disc size <1.63 mm2 or >2.43 mm2 underwent SD-OCT, confocal laser scanning tomography (CSLT), visual field testing, and clinical examination. Bruch's membrane opening-MRA BMO-MRW, RNFL thickness of SD-OCT and disc margin rim area (DM-RA) of CSLT were evaluated and analyzed for diagnostic power to detect glaucoma.
In healthy eyes with macrodiscs, mean BMO-MRW of 243.14 ± 43.12 μm was significantly smaller than BMO-MRW in microdiscs (338.97 ± 69.39; P < 0.001). Bruch's membrane opening-MRA was comparable between disc size groups with 1.22 ± 0.25 mm2 for macrodiscs and 1.26 ± 0.27 mm2 for microdiscs (P = 0.51), as was RNFL thickness (82.69 ± 15.76 μm versus 78.53 ± 11.01 μm, respectively; P = 0.28). Perimetric mean deviation was -8.7 ± 6.3 dB in glaucoma and -0.6 ± 1.60 dB in OHT patients. Correlation of BMO-MRA and visual field function was rho (ρ) = 0.70 (P < 0.001). Diagnostic power to differentiate glaucoma patients was highest for BMO-MRA. Partial area under the curve (pAUC) for BMO-MRA was 0.14 for specificity between 0.8 and 1.0, exceeding pAUCs of BMO-MRW (P < 0.001), RNFL thickness (P = 0.03), and DM-RA (P = 0.01).
Bruch's membrane opening-based minimum rim area measurements offer advantages compared to one-dimensional parameters assessing neuroretinal rim by SD-OCT. In nonglaucomatous eyes, BMO-MRA values seem comparable for the full range of disc sizes. Bruch's membrane opening-MRA surpasses other parameters in diagnostic power for glaucoma.