Following Macular Edema in RP patients: Comparing Optical Coherence Tomography (OCT) and Clinical Evaluation

Abstract

Abstract: : Purpose: To test the ability of the OCT scanner to detect and monitor (cystoid) macular edema ((C)ME) in patients with RP when correlated with the findings from clinical evaluations. Methods: Cross sectional OCT images through the fovea were evaluated in 81 eyes of 41 patients with RP over a course of eleven months with a scan done every six weeks. Six radiating 6-mm OCT scans at intervals of 30 degrees were obtained and the instrument computed a mean retinal thickness. Patients with thickening or cystoid appearance in the macula in the OCT scan images or an average thickness value > 150µm were flagged as having possible (C)ME. The results were compared with clinical evaluation of the patients which noted CME at the beginning, middle and end of this eleven month period. Results: 14 of the 41 patients were diagnosed with CME on at least one clinical exam. OCT and clinical evaluation agreed for 2/6 eyes for thickening without CME. 28 eyes clinically had CME at some point; 27 were measured by OCT and of them 22 were found to have CME. Of those that were not questionable clinically (22 eyes), OCT measured CME in 18 of 21 measured. 28 eyes were clinically evaluated for CME progression; 27 eyes were measured by OCT and 12 were found to progress the same. Of the 28, 22 were not questionable in terms of CME progression and OCT agreed for 14 of the 21 measured. Conclusions: There is a high degree of correlation between clinically detectable (C)ME at any visit and thickening and/or cystoid appearance in OCT images. There are discrepancies, however, in the clinical and OCT judgments of (C)ME changes over the follow-up period.

Keywords: clinical (human) or epidemiologic studies: nat • macula/fovea • clinical research methodology