Corneal endothelial cell loss after trabeculectomy and phacoemulsification in one or two steps: a prospective study.

OBJECTIVE: The objective of this study was to analyse the results of the surgical treatment of coexisting cataract and glaucoma and its effects on corneal endothelial cell density (CECD). METHODS: We include two longitudinal prospective studies: one randomised that included 40 eyes with open angle glaucoma that received one- (n = 20) or two-step (n = 20) phacotrabeculectomy and another that included 20 eyes that received phacoemulsification. We assess the impact of surgery on different clinical variables and in particular in CECD using Confoscan 4™ confocal microscopy and semiautomatic counting methods. RESULTS: Phacoemulsification and phacotrabeculectomy, but not trabeculectomy, increase significantly best-corrected visual acuity and anterior chamber depth and trabeculectomy and one- or two-step phacotrabeculectomy decreased similarly the intraocular pressure. We document percentages of endothelial cell loss of 3.1%, 17.9%, 31.6% and 42.6% after trabeculectomy, phacoemulsification and one- or two-step phacotrabeculectomy, respectively. The coefficient of variation did not increase significantly after surgery but the percentage of hexagonality decreased significantly after phacoemulsification and after two-step phacotrabeculectomy. CONCLUSIONS: Trabeculectomy, phacoemulsification and phacotrabeculectomy are surgical techniques that cause morphological changes and decrease the densities of the corneal endothelial cells. Trabeculectomy produces lesser endothelial cell loss than phacoemulsification, and phacoemulsification lesser cell loss than phacotrabeculectomy. Two-step phacotrabeculectomy (trabeculectomy followed 3 months later by phacoemulsification) causes more cell loss than one-step phacotrabeculectomy, and this could be due to the cumulative effects of two separate surgical traumas or to a negative conditioning lesion effect of the first surgery. For the treatment of coexisting glaucoma and cataract, one-step phacotrabeculectomy is the treatment of choice.

Corneal endothelial cell loss after trabeculectomy or after phacoemulsification, IOL implantation and trabeculectomy in 1 or 2 steps.

BACKGROUND: To assess endothelial cell damage after glaucoma surgery and combined glaucoma and cataract surgery in one or two steps using confocal biomicroscopy. METHODS: This is an observational retrospective study. Eighty eyes from 62 patients between 60 and 83 years of age were studied. Eyes fell into a control group (n = 21) and three experimental groups, in which trabeculectomy (group 1; n = 21) or trabeculectomy and phacoemulsification and intraocular lens implantation had been performed, in one (group 2; n = 21) or two (group 3; n = 17) steps between 6 months and 5 years before. RESULTS: In the control group, mean corneal endothelial cell density (+/-SD) was 2,619 +/- 319 cells/mm(2), whereas in the experimental groups 1, 2 and 3 it was 2,447 +/- 425, 1,968 +/- 342 and 1,551 +/- 323 cells/mm(2) respectively. Cell densities found in the combined surgery groups were significantly smaller than the densities of the control or trabeculectomy groups. The variation coefficient of the endothelial cell area (+/-SD) was 41.19 +/- 7.46% in the control group and 38.9 +/- 6.02, 42.37 +/- 9.53 and 45.71 +/- 11.96% in groups 1, 2 and 3 respectively, differences that were not statistically significant. The percentage of hexagonality (+/-SD) was 51.10 +/- 8.41% in the control group and 51.4 +/- 6.88, 45.13 +/- 8.40 and 42.37 +/- 9.53% in the experimental groups 1, 2 and 3 respectively, but again there were no significant differences between them. CONCLUSIONS: Combined trabeculectomy, phacoemulsification and intraocular lens implantation causes more endothelial cell damage than trabeculectomy alone, and the two-step combined procedure causes more damage to the endothelium than the one-step combined procedure.