Evaluation of a Qualitative Approach for Detecting Glaucomatous Progression Using Wide-Field Optical Coherence Tomography Scans

PURPOSE: To determine the effectiveness of detecting glaucomatous progression by a qualitative evaluation of wide-field (12 × 9 mm) scans on optical coherence tomography imaging. This method was compared to a conventional quantitative analysis of the global circumpapillary retinal nerve fiber layer (cpRNFL) thickness. METHODS: A total of 409 eyes with a clinical diagnosis of glaucoma or suspected glaucoma for which two wide-field scans were obtained at least 1 year apart (n = 125) and within one session (n = 284) were included to determine the sensitivity of detecting progression at 95% specificity. Qualitative OCT evaluation was performed in a similar manner to flicker chronoscopy by superimposing the two scans, and the progression probability was graded. A quantitative event-based analysis of the global cpRNFL thickness also was performed. RESULTS: Thirty-three and 25 eyes were deemed to have progressed based on qualitative and quantitative approaches, respectively (P = 0.152). A post hoc review of cases where the two methods disagreed revealed that all eyes missed by the quantitative analysis had established glaucomatous damage that appeared to show characteristic patterns of progression. All eyes missed by the qualitative evaluation appeared to be free of such established damage, and instead showed a generalized reduction in cpRNFL thickness. CONCLUSIONS: Qualitative evaluation of OCT imaging information more frequently detected change consistent with known patterns of glaucomatous progression than global cpRNFL thickness, warranting further studies to evaluate its value. TRANSLATIONAL RELEVANCE: A framework for qualitatively evaluating progressive glaucomatous changes on OCT imaging clinically shows promise.