Improvements in Optical Characteristics after Excision of an Overhanging Bleb Developed following Trabeculectomy

INTRODUCTION: To examine the corneal total higher-order aberrations before and after the excision of an overhanging bleb that developed following trabeculectomy. Case Presentation. Two patients who developed overhanging blebs following trabeculectomy with a fornix-based conjunctival flap using mitomycin C (MMC) were assessed. We measured the corneal total higher-order aberrations for a 4 mm pupil diameter using the TOPCON KR-1W wavefront analyzer and the visual acuity before and after bleb excision. The corneal total higher-order aberration (HOA) improved from 0.50 μm to 0.38 μm in case 1 and from 0.59 μm to 0.49 μm in case 2 after bleb excision. The intraocular pressure was identical before and after bleb excision in both cases. No significant changes in the best-corrected visual acuity (BCVA) were noted in case 1; however, BCVA was improved from 20/25 to 20/20 in case 2. Both cases showed improvements in the symptoms of dysesthesia. CONCLUSION: Excision of the overhanging bleb developed following trabeculectomy may have beneficial possibility in some cases where corneal total HOA is affected and reduces the symptoms of dysesthesia.