Evaluation of a Region-of-Interest Approach for Detecting Progressive Glaucomatous Macular Damage on Optical Coherence Tomography

PURPOSE: To evaluate a manual region-of-interest (ROI) approach for detecting progressive macular ganglion cell complex (GCC) changes on optical coherence tomography (OCT) imaging. METHODS: One hundred forty-six eyes with a clinical diagnosis of glaucoma or suspected glaucoma with macular OCT scans obtained at least 1 year apart were evaluated. Changes in the GCC thickness were identified using a manual ROI approach (ROI(M)), whereby region(s) of observed or suspected glaucomatous damage were manually identified when using key features from the macular OCT scan on the second visit. Progression was also evaluated using the global GCC thickness and an automatic ROI approach (ROI(A)), where contiguous region(s) that fell below the 1% lower normative limit and exceeded 288 μm(2) in size were evaluated. Longitudinal signal-to-noise ratios (SNRs) were calculated for progressive changes detected by each of these methods using individualized estimates of test–retest variability and age-related changes, obtained from 303 glaucoma and 394 healthy eyes, respectively. RESULTS: On average, the longitudinal SNR for the global thickness, ROI(A) and ROI(M) methods were −0.90 y(−1), −0.91 y(−1), and −1.03 y(−1), respectively, and was significantly more negative for the ROI(M) compared with the global thickness (P = 0.003) and ROI(A) methods (P = 0.021). CONCLUSIONS: Progressive glaucomatous macular GCC changes were optimally detected with a manual ROI approach. TRANSLATIONAL RELEVANCE: These findings suggests that an approach based on a qualitative evaluation of OCT imaging information and consideration of known patterns of damage can improve the detection of progressive glaucomatous macular damage.