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

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.

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.