Pathologic investigation failure of trabeculotomy.

PURPOSE: To investigate the reason for failure of trabeculotomy using trabeculectomy (TLE) specimens involving the area of previous trabeculotomy. MATERIALS AND METHODS: Thirteen TLE specimens from 13 patients with open-angle glaucoma were processed for transmission electron microscopy and light microscopy, involving immunohistochemical staining of thrombomodulin, D2-40 (podoplanin), and CD34. RESULTS: All intraocular pressure after trabeculotomy decreased to normal and then returned to the same or a higher level compared with that before TLE. Eleven and 2 TLE specimens were taken from areas with no peripheral anterior synechia (PAS) and PAS areas, respectively. The 4 types of histologic change in the trabecular meshwork were observed: (1) persistence of a disconnected trabecular meshwork with swelling or degeneration at the cut edge; (2) fusion of the trabecular meshwork; (3) a membrane covering the innermost trabecular meshwork; and (4) pigmented cell invasion into the disconnected trabecular meshwork at the PAS site. Schlemm canal (SC) opening into the anterior chamber and SC occlusion were observed in 2 and 8 eyes, respectively. CONCLUSIONS: Opening of SC into the anterior chamber observed in the eyes with failed trabeculotomy suggested that the enhancement of conventional routes may not be important for the intraocular pressure-lowering effect. All 4 types of histologic change in the trabecular meshwork, as mentioned above, may reduce enhancement of the newly created unconventional routes by trabeculotomy.

Trabeculectomy with mitomycin for open-angle glaucoma in phakic vs pseudophakic eyes after phacoemulsification.

OBJECTIVE: To determine whether previous phacoemulsification adversely affects surgical prognosis of trabeculectomy with mitomycin for open-angle glaucoma. METHODS: The study is a retrospective, consecutive, comparative case series. At 2 clinical centers, we reviewed 226 medical records of eyes with open-angle glaucoma undergoing initial trabeculectomy, including 175 phakic eyes (phakic group) and 51 pseudophakic eyes that had previously undergone phacoemulsification with superior conjunctival incision (pseudophakic group). Primary outcome was the probability of success after trabeculectomy. Surgical failure was defined as an additional glaucoma surgery or 1 of the following 3 criteria: intraocular pressure (IOP) of 21 mm Hg or greater (A); IOP of 18 mm Hg or greater (B); and IOP of 15 mm Hg or greater (C). Multivariable analysis was performed using the Cox proportional hazards model. RESULTS: The mean follow-up period was 37.5 months. The probability of success for criteria A, B, and C at 1 and 3 years in the phakic vs the pseudophakic group was 97.8% and 92.6%, respectively, vs 78.6% and 65.1%, respectively, for criterion A (P < .001); 92.9% and 81.3%, respectively, vs 72.8% and 63.7%, respectively, for criterion B (P = .004); and 73.1% and 54.2%, respectively, vs 53.1% and 38.4%, respectively, for criterion C (P = .009). The multivariable model confirmed that pseudophakia independently contributes to surgical failure (criterion A relative risk, 4.59 [P < .001]; criterion B, 2.88 [P = .004]; and criterion C, 2.02 [P = .009]). The pseudophakic group required more postoperative laser suture lysis (P = .01). CONCLUSION: Previous phacoemulsification is a prognostic factor for surgical failure of trabeculectomy with mitomycin for open-angle glaucoma.

Long-term relationship between intraocular pressure and visual field loss in primary open-angle glaucoma.

PURPOSE: To investigate the dependence upon intraocular pressure (IOP) of the progression of visual field defects in eyes with primary open-angle glaucoma (POAG), in which the mean IOP was maintained at < or =21 mm Hg. METHODS: This study involved 100 eyes with POAG, which were followed up for > or =5 years. The mean IOP levels were maintained at < or =21 mm Hg during the follow-up period. The relationship between the IOP and the progression of visual field defects, which was scored using the Advanced Glaucoma Intervention Study criteria, was investigated retrospectively. RESULTS: Compared with the baseline scores, the visual field defect scores had significantly worsened by the end of the follow-up period (P<0.0001, Wilcoxon paired signed rank test). The change in the visual field defect score (2.5+/-0.5) in eyes with average IOP levels of > or =16 mm Hg (n=36) was significantly greater (P=0.031, Mann-Whitney U test) than the change (1.3+/-0.3) in eyes with average IOP levels of <16 mm Hg (n=64). Moreover, IOP of > or =18 mm Hg made a major contribution to the aggravation of visual field defects in eyes with POAG. CONCLUSIONS: Eyes with POAG and with mean IOP levels maintained at < or =21 mm Hg underwent IOP-dependent progression of their visual field defects. Our results suggest that further IOP lowering would be beneficial in such cases.

A case of Chandler's syndrome revealed by ultrastructural studies of the trabecular meshwork.

PURPOSE: To investigate ultrastructural changes in the aqueous outflow route and discuss the mechanisms associated with intraocular pressure (IOP) elevation in a patient with presumably early stage Chandler's syndrome. METHODS: A 47-year-old man underwent trabeculectomy because of elevated IOP. A specimen obtained during surgery was studied by transmission electron microscopy. RESULTS: Electron microscopy showed the presence of a monolayer composed of corneal endothelium-like cells and thick basement membrane-like material. Neovascularization was also observed in the corneoscleral trabeculum. CONCLUSIONS: Our results indicate that several mechanisms, including the formation of basement membrane-like tissue, infiltration of inflammatory cells and neovascularization, might contribute to the elevation of IOP in Chandler's syndrome. These may occur even when there is no history of conspicuous inflammatory reaction in the anterior ocular segments.