Increases in central retinal artery blood flow in humans following carotid artery and stellate ganglion irradiation with 0.6 to 1.6 microm irradiation.

The authors applied near-infrared low-level laser irradiation (LLLI) directed to the stellate ganglion (SG) and to the common carotid artery (CCA), and compared the effects on central retinal artery blood flow using color pulse Doppler sonography. In 10 healthy volunteers, LLLI (0.92 W, 1 : 1 duty cycle, 10 min) to both the SG and CCA significantly increased peak systolic blood velocity in the ophthalmic artery (p<0.001, each) and central retinal artery (p<0.001, each) without changes in vessel resistance. Irradiation to the CCA produced a stronger effect than that to the SG in the ophthalmic artery (p=0.007) and central retinal artery (p=0.031). These data suggest that LLLI to the SG or to the CCA is a useful therapy for increasing the retrobulbar blood flow, with irradiation directed to the CCA being more effective than that directed to the SG in clinical settings.

Quantitative analysis of posterior capsule opacification of hydrophobic acrylic intraocular lenses.

Posterior capsule opacification (PCO) remains a common complication of modern cataract surgery, although both modification of materials used and changes in the intraocular lens (IOL) optic edge design have helped to decrease its incidence slightly. Recently, various kinds of quantitative methods have been developed for measuring PCO. The purpose of this study was to compare the quantitative analysis of PCO between different types of IOL designs. Patients enrolled in the study had age-related cataract and underwent uneventful cataract surgery and implantation of either the AcrySof MA30BA (Alcon) or the Sensor AR40e (AMO), which are differently designed hydrophobic acrylic IOLs with a sharp-edged optic design. Postoperative examination was performed at 6 months. Retroillumination photographs of each eye were obtained, and the degree of PCO was assessed using the Evaluation of Posterior Capsule Opacification (EPCO) system. Grade 1 PCO was noted in both the MA30BA and the AR40e groups. There was no significant difference in the mean PCO score between the MA30BA and AR40e groups. Although the sharp-edged optic designs of both IOLs might similarly inhibit PCO at 6 months, a long-term follow-up period is needed to determine if any PCO differences occur between these 2 hydrophobic acrylic IOLs.

Two cases of true exfoliation of the lens capsule after cataract surgery.

True exfoliation of the lens capsule is known to be associated with glassblower's cataract, which is caused by extended exposure to excessive heat. Furthermore, inflammation and trauma are also considered to be predisposing factors. We report two cases of true exfoliation that were confirmed after cataract surgery. Neither patient exhibited true exfoliation before cataract surgery. In addition, neither patient had a history of occupation with exposure to excessive heat, inflammation or trauma. We observed the anterior lens capsules of these two patients with slit-lamp microscopy before and after cataract surgery. True exfoliation disappeared by adhering to the anterior capsule in both cases, and there were no complications during the observation period.

Anterior chamber irrigation with an ozonated solution as prophylaxis against infectious endophthalmitis.

PURPOSE: To assess the validity of anterior chamber irrigation with an ozonated solution as prophylaxis against endophthalmitis. SETTING: Department of Ophthalmology, Nippon Medical School, Tokyo, Japan. METHODS: Viability of human corneal endothelium in culture was assessed by the WST-8 assay, lactate dehydrogenase (LDH) release assay, and trypan blue exclusion assay after exposure to a 4 to 40 parts per million (ppm) solution for 10 to 60 seconds. The in vivo effect was observed 1 week after irrigation of a 4 ppm solution in the rabbit anterior chamber by trypan blue exclusion assay. Bactericidal efficacy of the anterior chamber irrigation with the 4 ppm solution was examined by bacterial colony count of the aqueous humor following methicillin-resistant Staphylococcus aureus (MRSA) contaminated intraocular lens implantation in the porcine eye. RESULTS: The WST-8 assay revealed no significant reduction of viability with 10-second exposure to a 4 ppm solution. Lactate dehydrogenase release and trypan blue exclusion assays similarly demonstrated little damage after 60-second exposure to a 4 ppm solution. In the rabbit cornea 1 week after treatment, damage caused by 30-second exposure to a 4 ppm solution was not significant. The MRSA colony count documented almost complete bactericidal action with 5-second exposure to the 4 ppm solution when no ophthalmic viscosurgical device existed in the anterior chamber. CONCLUSION: Limited damage to the corneal endothelium after 10-second exposure and potent bactericidal action with 5-second exposure suggests the validity of anterior chamber irrigation with a 4 ppm ozonated solution as prophylaxis against endophthalmitis.

Involvement of macrophage chemotactic protein-1 and interleukin-1beta during inflammatory but not basic fibroblast growth factor-dependent neovascularization in the mouse cornea.

Corneal neovascularization develops in several pathologic conditions, but its underlying mechanisms remain elusive. We used a mouse inflammatory corneal model (corneas cauterized with silver nitrate) and assessed the role of monocyte/macrophage-attracting factors, macrophage chemotactic protein-1 (MCP-1), and a proinflammatory cytokine, IL-1beta, on macrophage recruitment and neovascularization. Both MCP-1, IL-1beta protein, and mRNA levels increased markedly 12 hours after the chemical cauterization. In situ hybridization showed that MCP-1 was located in corneal epithelial cells, and IL-1beta was located in corneal epithelial cells and infiltrating inflammatory cells. In addition, double staining of corneas with antibodies specific for monocytes/macrophages and IL-1beta revealed that IL-1beta was found in infiltrating monocytes/macrophages at Day 2 after cauterization. Both IL-1beta and MCP-1 induced neovascularization in a rat cornea model, and the cauterization-induced corneal neovascularization was partially inhibited by subconjunctival injection of anti-IL-1beta or anti-MCP-1. Coadministration of two antibodies inhibited corneal neovascularization slightly more than that by the administration of each. In contrast, administration of the anti-MCP-1 or anti-IL-1beta showed minimal inhibition of basic fibroblast growth factor-driven corneal neovascularization by mouse cornea assay. Cauterized corneas treated with anti-MCP-1 antibody had significantly fewer monocytes/macrophages than control. These results indicate the existence of distinct monocyte/macrophage-involved angiogenic pathways in mouse cornea, in which MCP-1 released from corneal epithelial cells attracts monocytes/macrophages into the cornea, where they release IL-1beta leading to inflammatory neovascularization. In addition, the IL-1beta and MCP-1 released from the corneal epithelial cells may directly induce corneal neovascularization.

The effect of up- and downregulation of MnSOD enzyme on oxidative stress in human lens epithelial cells.

PURPOSE: Gene knockouts serve as useful experimental models to investigate the role of antioxidant enzymes in protection against oxidative stress in the lens. In the absence of gene knockout animals for Mn-containing superoxide dismutase (MnSOD), the effect of this enzyme on oxidative stress was investigated in a human lens epithelial cell line (SRA 01/04) in which the enzyme was up- or downregulated by transfection with sense and antisense expression vectors for MnSOD. METHODS: Human lens epithelial cells (SRA 01/04) were transfected with plasmids containing sense and antisense human cDNA for MnSOD. The enzyme levels were determined by Western blot analysis and immunocytochemistry. The protective effect of the enzyme against the cytotoxicity of H(2)O(2) was evaluated by cell viability, DNA strand breaks, and morphologic changes observed by transmission electron microscopy. In addition, the protective effect of this enzyme against photochemically induced stress and UVB irradiation in cells was assessed by measuring the damage of cellular DNA. RESULTS: The MnSOD level in upregulated cells was three times higher than in downregulated cells, and the enzyme surrounded the nucleus. Cells with elevated enzyme levels were more resistant to the cytotoxic effect of H(2)O(2) with greater cell viability. MnSOD-deficient cells showed dramatic mitochondrial damage when exposed to 50 micro M H(2)O(2) for 1 hour. Similarly, oxidative challenge by H(2)O(2), photochemically generated reactive oxygen species, or UVB irradiation produced greater DNA strand breaks in MnSOD-deficient cells than in those in which the enzyme was upregulated. CONCLUSIONS: These findings demonstrate the protective effect of MnSOD in antioxidant defense of cultured lens epithelial cells. This approach to modulating the enzyme level in cultured cells provides a new experimental model for study of the role of antioxidant enzymes in the lens.