The CLASS Surgical Site Characteristics in a Clinical Grading Scale and Anterior Segment Optical Coherence Tomography: A One-Year Follow-Up

PURPOSE: We combined a clinical grading scale and swept source anterior segment OCT to describe the successful and failed CLASS. MATERIAL AND METHODS: 23 patients in the successful group and 17 patients in the failed group were compared in terms of the IBAGS grades and AS-OCT findings at one, three, and twelve months postoperatively. RESULTS: The majority in the successful group presented shallow blebs (91%, 57%, and 52% at 1M, 3M, and 12M, resp.). 59% of the failed group presented no bleb (H0 E0) from the early postoperative period with the rate increasing to 88% at 3M and 100% at 12M. The scleral lake was detected in all the successful patients. The successful group showed significantly higher rates of TDM integrity (P < 0.001), IF (P < 0.001), and SCF (P < 0.05), but there were no significant differences in the rates of microcysts between the groups (P > 0.05). We found a significant decrease in the SL anteroposterior extent (P=0.003) and SL height (P < 0.001) over time, with no significant correlation between the above parameters and IOP. CONCLUSIONS: The subconjunctival bleb may be a sign of the successful CLASS when it matches the AS-OCT findings of TDM integrity, maintained scleral lake, and intrascleral fluid. A validated OCT pixel intensity measurement is required to evaluate the bleb reflectivity.