Consistency Between Humphrey Guided Progression Analysis (GPA) And Optical Coherence Tomography (OCT) In Identification And Diagnosis Of Glaucoma Progression

Objectives:To evaluate the consistency between Humphrey guided progression analysis (GPA) and optical coherence tomography (OCT) in identifying and diagnosis of glaucoma progression, and to determine the most sensitive OCT parameters in identifying glaucomatous structural damage.Methods:This study included 142 eyes of 142 patients. Images were obtained by Stratus OCT (Carl Zeiss Meditec, Inc.,Shanghai) along with standard automated perimetry (SAP) visual fields.The median follow up time was 2.8 years.Glaucoma progression was judged by the guided progression analysis software (Carl Zeiss Meditec, Inc.,Shanghai). Random coefficient models and receiver operating characteristic (ROC) curves were applied to evaluate the relationship between OCT parameters over time and progression as judged by GPA.Results:From all 142 eyes,19 (13%) eyes showed progression (dealt with as the PROGRESSORS group) over time by standard automated perimetry guided progression analysis-SAP GPA. Three OCT parameters were able to distinguish progressors from nonprogressors; average thickness, inferior average and Rim area (VCS).Mean rates of change in RNFL average thickness were significantly higher in progressors than in nonprogressors (-3.43μm/y vs.-0.720μm/y; P<0.05) with sensitivity of 67.5% and specificity of 94.7%.The mean rate of change for inferior average and Rim area(VCS) parameters were higher in progressors than in nonprogressors (P<0.05), with sensitivity of 60.2%,53.7% and specificity of 73.7%,73.7% respectively.These three parameters had the largest areas under the ROC curves; average thickness (0.828), inferior average (0.716),and rim area(VCS) (0.641).Conclusion:The Strarus OCT significantly detected glaucoma progression in all cases showing progression by SAP-GPA, with high specificity and moderate sensitivity. RNFL parameters performed significantly better than ONH parameters in distinguishing progressors from nonprogressors with special emphasis on RNFL average thickness parameter. Stratus OCT is a useful technique for detection of glaucoma progression.