Wide-field contact specular microscopy analysis of corneal endothelium post trabeculectomy

Purpose This study investigates the possible role of the filtration bleb in the continuous decrease in corneal endothelial cell (CEC) density observed following trabeculectomy. Methods This study involved 51 eyes of 37 glaucoma patients who underwent trabeculectomy. The CEC density was determined by contact specular microscopy in three areas: (1) the cornea center, (2) near the trabeculectomy filtration bleb, and (3) the opposite side of the bleb. The eyes were grouped according to post-surgical follow-up years: 0–1 (Group 1), 1–2 (Group 2), 2–3 (Group 3), 3–4, (Group 4), and 4+ years (Group 5). Results The mean CEC densities at the opposite side of the bleb, in the cornea center, and near the bleb were 2210 ± 487, 1930 ± 528, and 1519 ± 507 cells/mm 2 , respectively, in all eyes. The CEC density was significantly lower near the bleb than at the other two sites. The coefficient of variation was significantly higher near the bleb than at the other two sites. The CEC densities at the cornea center and at the opposite side of the bleb showed no significant differences. However, the CEC densities near the bleb showed time-dependent decreases to 1790, 1601, 1407, 1339, and 1224 cells/mm 2 for Groups 1, 2, 3, 4, and 5, respectively. Conclusions CEC density following trabeculectomy decreased near the bleb, but not at the cornea center, suggesting that the involvement of the filtration bleb in CEC density loss should be further examined to elucidate the pathology of CEC loss following trabeculectomy.