Purpose: To evaluate morphological abnormalities of Schlemm's canal (SC) among primary open-angle glaucoma (POAG) patients with a family history of POAG (group A), those without a family history of POAG (group B), and patients with normal-tension glaucoma (group C) from the aspect of aging. Methods: A total of 160 trabeculectomy specimens from 133 POAG patients were processed for light microscopy using immunohistochemical staining of thrombomodulin and transmission electron microscopy. The following parameters were statistically evaluated: SC length, the percentage of the thrombomodulin-negative area (PTNA) of SC, and the inner-wall SC endothelial cell density (SC-ECD/100 μm). Results: No significant differences in age were observed among the three groups (group A: 56.71 ± 14.83; group B: 58.13 ± 18.13; group C: 56.61 ± 9.78). Length of SC in the group A patients (198.70 ± 81.65 μm, n = 70 eyes) was significantly shorter than in group B (250.30 ± 70.83 μm, n = 67 eyes), and group C (277.70 ± 65.52 μm, n = 23 eyes) patients. A positive correlation of patient age and SC length was observed in group B (r = 0.45, P = 0.0013), but SC length in group A tended to decrease with aging (r = −0.22, P = 0.07). No significant difference in SC was found between group A and B patients before age 50 years (P = 0.30). Correlations between patient age and increase of PTNA (r = 0.38, P = 0.0013) and patient age and decrease of SC-ECD (r = −0.53, P = 3.95 × 10⁻⁶) were observed only in the group B cases. Conclusions: Our findings suggest that SC in group A may easily collapse during middle age, while SC in group B remains open and SC endothelial cells drop out at around middle age.

S analyzed using the Kaplan-Meier method, defining death as: (1) Intraocular pressure (IOP) <6 mmHg, or ≥22 mmHg, and <20% reduction of preoperative IOP, (2) additional glaucoma surgery, (3) loss of light perception. Prognostic factors of age, sex, previous surgery, type of glaucoma, synechial closure, preoperative IOP, type of GDI (single-, double-plate Molteno, Baerveldt 350) and GDI combined with trabeculectomy were investigated employing proportional hazards analysis. Results: One hundred and twenty-four eyes of 109 patients aged 53.3 ± 7.8 years old were analyzed. Types of GDI were single-plate (15.3%), double-plate Molteno (71.8%), and Baerveldt 350 (12.9%). The results of survival rate analysis were 86.1, 71.1, 71.1, and 64.6% for 1, 3, 5, and 10 years respectively. Thirty-four eyes (27.4%) died because of uncontrolled IOP (19.4%), loss of light perception (5.6%), and additional glaucoma surgery (2.4%). Single-plate Molteno was the only risk factor for failure. Persistent unphysiological hypotony (0.8%) and bullous keratopathy (5.6%) were observed. Conclusion: Nonvalved GDI surgery and GDI combined with trabeculectomy using nonabsorbable tube ligature proved to be an excellent device for any type of glaucoma in Japanese patients. Hypotony and corneal endothelial loss are the most serious complication in the long-term results of our patients....

Glaucoma is one of the primary causes of blindness worldwide. Canal opening surgery, a type of minimally invasive glaucoma surgery (MIGS) applied in cases of mild to moderate glaucoma, has gained increasing popularity in recent years due to its efficacy in reducing the intraocular pressure, its safety profile, the simplicity of its technique, and the reduced likelihood of compromised vision. Nevertheless, the existing body of histopathological studies remains insufficient for a comprehensive understanding of post-surgical wound healing. Consequently, debates persist among researchers regarding the mechanism through which Schlemm’s canal opening surgery reduces the intraocular pressure, as well as the surgical techniques that may impact the outcomes and the factors influencing surgical success. As the history of MIGS is relatively short and lacks sufficient systemic reviews or meta-analyses evaluating the influence of individual factors, this review was conducted to illuminate the disparities in researchers’ opinions at the current stage of research.

In this retrospective study, we investigated vascular abnormalities in sarcoidosis using fluorescein gonioangiography (FGA) to detect angle neovascularization (ANV), fundus fluorescein angiography (FFA), and pathological specimens from the aspects of microangiopathy. In 57 sarcoidosis patients, clinical data was reviewed by dividing the cases into three groups (Group I: histologically diagnosed; Group II: positive bilateral hilar lymphadenopathy (BHL); Group III: negative BHL). The FFA, FGA, and pathological examination data in the autopsy eyes and trabeculectomy specimens were investigated. FGA and FFA detected ANV (91%) and nodule-associated abnormalities (87%), respectively. No intraocular pressure (IOP) elevation was observed after continuous topical betamethasone, except in the steroid responder group. Maximum IOP had significant correlation with nodules in the angle (p = 0.02696) and visual field defect (p = 0.0151). Granulomas adjacent to blood vessels, including the Schlemm’s canal, and thickening of the retinal blood vessel wall caused occlusion of those vessels. Photocoagulation was required for retinal tears (14%) and the retinal blood vessel occlusion (7%). Suppression of IOP elevation via continuous topical betamethasone may be important to avoid irreversible outflow-route changes and optic-nerve damage, and the concept of microangiopathy in ocular sarcoidosis may be important for understanding the proper treatment of serious complications.