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.

Stability of the central visual field after modern trabeculectomy techniques in eyes with advanced glaucoma.

PURPOSE: To review the surgical results and complications of trabeculectomy techniques in patients with advanced glaucoma and threatened fixation. METHODS: Trabeculectomy had been carried out on 49 advanced glaucoma patients (49 eyes) using mitomycin C and postoperative laser suture lysis. The clinical records prior to and 2 months after surgery were reviewed, and the long-term surgical outcomes were determined. RESULTS: Two months after surgery there were no eyes with fixation loss. Intraocular pressure (IOP) levels were reduced from 22.8 +/- 6.0 to 11.7 +/- 4.7 mmHg. Kaplan-Meier survival analysis showed that the success rate in achieving IOPs of 15 mmHg or lower 5 years after surgery was 70%. The chance of visual acuity remaining within two lines of the preoperative level was 75%. In 29 of the 49 eyes, visual acuities remained at their preoperative level at the time of the final visit, but had decreased to less than 0.1 in three eyes (cataract progression, n = 2; fixation loss, n = 1). CONCLUSION: The results suggest that laser suture lysis and stepwise management of IOP levels, which are performed as part of the modern postoperative management of trabeculectomy, decrease the frequency of fixation loss during the early postsurgical phase.

Loss of vision due to a physiologic pituitary enlargement during normal pregnancy.

BACKGROUND: Physiologic pituitary enlargement during normal pregnancy is well known, but we are unaware of previous reports on a natural course of visual loss due to this disease. METHODS: A 30-year-old woman presented blurred vision in the left eye from the 30th week of pregnancy. At 38 weeks visual acuity was 0.9 in the left eye. Automated perimetry revealed a mild central visual defect in the left eye. A magnetic resonance imaging (MRI) scan revealed pituitary enlargement with compression of the anterior optic chiasm. We observed the natural course of this case. RESULTS: At 16 weeks after delivery, visual acuity was 1.5 in both eyes with normal visual field, and an MRI scan revealed a normal-sized pituitary without compression of the optic chiasm. CONCLUSIONS: Ophthalmologists should be aware of visual loss by physiologic pituitary enlargement to avoid unreasonable neurosurgical procedures.

Rho-associated protein kinase inhibitor, Y-27632, induces alterations in adhesion, contraction and motility in cultured human trabecular meshwork cells.

We investigated the roles of Rho-associated protein kinase (ROCK) in regulating activities such as adhesion, contraction and migration in cultured human trabecular meshwork (TM) cells. Human TM cells in culture were treated with Y-27632, a specific ROCK inhibitor. Trypan blue exclusion test and TUNEL staining showed little or no direct toxicity of Y-27632 on TM cells. By MTT assay, Y-27632 did not significantly affect the proliferation of TM cells. The cell adhesion assay showed that Y-27632 promoted the cell adhesiveness to both fibronectin and collagen type I in a dose-dependent manner. Collagen gel contraction activity of TM cells was significantly inhibited by the treatment of Y-27632 in a dose-dependent manner. The addition of Y-27632 accelerated motility of TM cells in wound healing assay. Phosphorylated LIM kinase 2 and cofilin, related to actin bundling and integrin clustering, were dephosphorylated (activated) by Y-27632. In conclusion, Y-27632 elicits profound effects on TM cell activities including adhesion, gel contraction, and cell motility. These Y-27632-induced changes of TM cells may be relevance to the physiology of the aqueous outflow system.

NMDA-induced retinal injury is mediated by an endoplasmic reticulum stress-related protein, CHOP/GADD153.

We investigated the role of an endoplasmic reticulum stress-associated protein, CHOP/GADD153, after NMDA-induced mouse retinal damage. After injection of NMDA into the vitreous, TUNEL-positive cells were detected in the retinal ganglion cell layer (GCL) and inner nuclear layer (INL) at 6 h after NMDA injection, and these gradually increased in number up to 24 h. Analysis by real-time RT-PCR revealed that CHOP mRNA was induced by about 3-fold, at 2 h after NMDA injection. Immunoreactivity for the CHOP protein was intense in cells of the GCL following NMDA treatment. Immunoblot analysis showed that NMDA injection increased the expression of CHOP protein in the retina. Compared with wild-type mice, CHOP/ mice were more resistant to NMDA-induced retinal cell death as determined by TUNEL assay. At 7 days after NMDA treatment, the thickness of the inner plexiform layer and INL were larger in CHOP/ mice than in wild-type mice. The number of residual cells in the GCL following NMDA treatment was significantly higher in CHOP/ mice than in wild-type mice. In conclusion, CHOP is induced in mouse retina by NMDA treatment, and CHOP/ mice are more resistant to NMDA-induced retinal damage, suggesting that CHOP plays an important role in NMDA-induced retinal cell death.

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.