Published papers

We evaluated contrast visual acuity and irregular astigmatism during the early stage after self-sealing small incision cataract surgery in 22 eyes. Three days after surgery, the corrected visual acuity and visual acuity for high contrast chart reached the average values 3 months after surgery. It took 2 weeks for the visual acuity for medium and low contrast chart to reach the average value 3 months after surgery. Irregular corneal astigmatism showed significant increases 3 and 5 days after surgery from preoperative values. It returned to the preoperative value 2 weeks after surgery. There were no differences before and after surgery in regular astigmatism, surface regularity index and surface asymmetry index. The findings show that irregular astigmatism may be a factor in the recovery of visual acuity for medium and low-contrast chart during the early stage after self-sealing small incision cataract surgery.

Purpose: To evaluate the clinical performance of a five-zone refractive multifocal intraocular lens (AMO, model MPC-25NB, Array®). Methods: We performed a retrospective clinical trial of 31 cataract patients (mean age 64.3 years). The parameters studied were intraoperative and postoperative complications, distance and near visual acuity, spectacle use, decreased number of corneal endothelial cells, contrast sensitivity, percentage of glare disability, near binocular vision, and depth of focus. Results: Intraoperatively, iris damage occurred in two eyes (4.2%), vitreous loss in one eye (2.1%), and consecutive rupture of Zinn's zonule and vitreous in one eye (2.1%). Postoperatively, posterior capsule opacification was observed in two eyes (4.2%), temporary intraocular pressure increase in one eye (2.1%), and cystoid macular edema in one eye (2.1%). Uncorrected distance visual acuity of 20/40 or better was achieved by 34 of 37 eyes (91.9%) with less than 1.5 diopters of preoperative keratometric astigmatism; best corrected distance acuity of 20/20 or better was achieved by 41 of 45 eyes (91.1%). Near visual acuity with distance correction of 20/40 or better was achieved by 29 of 43 eyes (67.4%). These data were compared retrospectively with data from control patients who received monofocal lenses, and no significant differences in the decreased number of corneal endothelial cells were found. Mean contrast sensitivities were within normal range for all spatial frequencies. Percentage of glare disability and near binocular vision were within normal limits. Conclusions: Eyes implanted with the five-zone refractive multifocal lens showed better near visual acuity than control eyes and compared favorably in other aspects of visual function, indicating that these lenses are effective and safe.

Light and electron microscopy were used to examine yellow-white opacities around the area of abnormal corneal stromal vascularization from the limbus in 2 patients with hypercholesterolemia. Intracellular lipid droplets were noted in keratocytes near capillaries, and needle-shaped crystals of cholesterol were seen extracellularly, evidence that the opacities resulted from deposition of lipid in the stroma. On the basis of clinical findings in these 2 patients, we hypothesized that accumulation of lipid was responsible for 19 opacities in 32 patients with abnormal corneal stromal vessels. Correlations were found between lipid deposition and serum cholesterol levels in these patients, suggesting that hypercholesterolemia (>200 mg total cholesterol/dl) and abnormal corneal vascularization place a patient at high risk of developing lipid keratopathy (LK). In the early stage of LK, ablation of vascular channels or normalization of serum cholesterol levels could prevent progression of lipid deposition and helped lipid infiltrate to resolve. In this way, early treatment can be effective in preventing the occurrence of LK itself or progression of opacity.

A 21 year old male presented with bilateral lens dislocation. He showed skeletal abnormalities simulating Marfan syndrome, mental retardation and history of convulsion during childhood. He was diagnosed as homocystinuria by laboratory studies. After five years of follow-up, rhegmatogenous retinal detachment developed in the right eye, which was brought to cure by multiple surgeries. Retinal detachment in homocystinuria was difficult to detect and treat because of concomitant systemic and mental problems.

Purpose. Small incision cataract surgery resulted in early postoperative recovery of visual function because of less intraocular inflammation and irregular astigmatism. Using the Variable Contrast Visual Acuity Charts (VCVAC), we reported that improved visual acuities (VAs) with intermediate- and low-contrast charts correlated negatively with the postoperative level of intraocular inflammation (ARVO 1995). In the present study we observed changes in contrast VA and irregular astigmatism at several time points postoperatively. Methods. Sixteen patients (22 eyes) aged 41-89 years (mean, 65.5) with no ocular pathologies except for cataract were selected as study patients. Phacoemulsification and intraocular lens implantation were performed through a 3-5 mm self-sealing incision. The irregular corneal astigmatism was quantified from the difference between the actual refractive power and the sine curve that approximates the refractive power of the regular cornea. The contrast VA was measured using the VCVAC, which consists of low- (2.5%), intermediate- (15%), and high- (90%) contrast charts. Those measurements were performed preoperatively and at 3 and 5 days, 2 weeks, and 1 month postoperatively. Results. The degree of regular astigmatism was not statistically different at any time postoperatively. However, the degree of irregular astigmatism within the central 2 mm of the cornea was 0.59D at 3 days and 0.51D at 5 days, and improved to 0.38D at 2 weeks postoperatively. The irregular astigmatism at 3 and 5 days postoperatively, which was statistically higher than that preoperatively (0.31D), was negatively correlated with the recovery of VAs with intermediate and low contrast. Conclusions. The irregular astigmatism may also influence the early postoperative VA with intermediate- and low-contrast charts as well as intraocular inflammation.

Purpose.In cataract surgery, sodium hyaluronate(Na-HA) is used not only to maintain the anterior chamber but also to protect ocular tissue such as the corneal endothelium. We compared the protective effects of different molecular weights of Na-HA during phacoemulsification(PEA). Methods.78 postmortem porcine eyes and Na-HA of three different molecular weights labeled with fluorescenct amine (FA-HA) were used: 42×104(group A) , 113×104(group B), and 167×104(group C). 500 μ1 of Na-HA was injected into the anterior chamber and irrigation and aspiration (I/A) or PEA was performed. To measure the endothelial damage, the cornea was dissected at the limbus, and using 0.25% trypan blue, the stained area, i.e., the damaged area was analysed using a video system (Pias LA-555). To evaluate the amount of FA-HA binding to the corneal endothelium, the corneal section was digested by acetate buffer, including 0.25% actinase, fluorescence was measured. Results. Following I/A, a mean area of staining(mm2) was 0.008± 0.016 in group A (4 eyes), 0.00± 0.00 in group B (4 eyes) and C (4 eyes). Following PEA, a mean area of staining (mm2) was 0.364 ± 0.328 in group A (4 eyes), 0.428± 0.841 in group B (4 eyes) and 0.074± 0.086 in group C (4 eyes). The average amount of residual FA-HA (μ g/mg dry Wt.) after PEA was 0.386+ 0.959 in group A(8 eyes), 23.9± 5.66 in group B(7 eyes), and 3.59± 1.38 in group C(7 eyes). The residual level in group B was statistically greater than the other groups (P<0.01). Conclusion Compared with different molecular weight of Na-HA, the residual level of Na-HA after PEA was significantly different, however, the protective effect was not clinically different.

PURPOSE: To evaluate the clinical performance of a five-zone refractive multifocal intraocular lens (AMO, model MPC-25NB, Array). METHODS: We performed a retrospective clinical trial of 31 cataract patients (mean age 64.3 years). The parameters studied were intraoperative and postoperative complications, distance and near visual acuity, spectacle use, decreased number of corneal endothelial cells, contrast sensitivity, percentage of glare disability, near binocular vision, and depth of focus. RESULTS: Intraoperatively, iris damage occurred in two eyes (4.2%), vitreous loss in one eye (2.1%), and consecutive rupture of Zinn's zonule and vitreous in one eye (2.1%). Postoperatively, posterior capsule opacification was observed in two eyes (4.2%), temporary intraocular pressure increase in one eye (2.1%), and cystoid macular edema in one eye (2.1%). Uncorrected distance visual acuity of 20/40 or better was achieved by 34 of 37 eyes (91.9%) with less than 1.5 diopters of preoperative keratometric astigmatism; best corrected distance acuity of 20/20 or better was achieved by 41 of 45 eyes (91.1%). Near visual acuity with distance correction of 20/40 or better was achieved by 29 of 43 eyes (67.4%). These data were compared retrospectively with data from control patients who received monofocal lenses, and no significant differences in the decreased number of corneal endothelial cells were found. Mean contrast sensitivities were within normal range for all spatial frequencies. Percentage of glare disability and near binocular vision were within normal limits. CONCLUSIONS: Eyes implanted with the five-zone refractive multifocal lens showed better near visual acuity than control eyes and compared favorably in other aspects of visual function, indicating that these lenses are effective and safe.

Purpose. To determine whether basic fibroblast growth factor (bFGF) and transforming growth factor-β2 (TGF-β2) influence the contractile activity and the expression of α-smooth muscle actin (α-SMA) in bovine lens epithelial cells (LECs). To examine whether modulation of contractile activity by these growth factors depends on changes of α-SMA expression. Methods. Bovine LECs were cultured in collagen gel in MED 5 medium (F-12 nutrient mixture supplemented with 5% fatal bovine scrimp) with or without bFGF (1 to 100 ng/ml) or TGF-β2 (0.01 to 10 ng/ml). To evaluate collagen gel contraction, the longest and shortest diameters of the gels were measured daily for 7 days, and the area was determined. Detection of α-SMA in the gels was performed immunohistochemically using a mouse monoclonal antibody against α-SMA. The percentage of α-SMA-positive cells to the total number of cells was determined. Results. Control gels cultured with MED 5 medium alone contracted to 15.8% ± 3.4% of their original area after 7 days. TGF- β2 significantly increased this contraction in a dose-dependent manner, whereas bFGF significantly decreased it. Approximately 30% of cells in the control gels were α-SMA positive. TGF-β2 significantly increased the α- SMA positivity dose dependently, whereas bFGF significantly decreased it. The percent positivity for α-SMA and the gel area showed a significant negative correlation. Conclusions. TGF-β2 increased collagen gel contraction and α- SMA expression in bovine LECs, whereas bFGF decreased these parameters. Because collagen gel contraction was correlated with α-SMA expression, the modulation of LEC contractile activity by growth factors may be related to an effect on α-SMA.

PURPOSE: To determine whether basic fibroblast growth factor (bFGF) and transforming growth factor-beta 2 (TGF-beta 2) influence the contractile activity and the expression of alpha-smooth muscle actin (alpha-SMA) in bovine lens epithelial cells (LECs). To examine whether modulation of contractile activity by these growth factors depends on changes of alpha-SMA expression. METHODS: Bovine LECs were cultured in collagen gel in MED 5 medium (F-12 nutrient mixture supplemented with 5% fetal bovine serum) with or without bFGF (1 to 100 ng/ml) or TGF-beta 2 (0.01 to 10 ng/ml). To evaluate collagen gel contraction, the longest and shortest diameters of the gels were measured daily for 7 days, and the area was determined. Detection of alpha-SMA in the gels was performed immunohistochemically using a mouse monoclonal antibody against alpha-SMA. The percentage of alpha-SMA-positive cells to the total number of cells was determined. RESULTS: Control gels cultured with MED 5 medium alone contracted to 15.8% +/- 3.4% of their original area after 7 days. TGF-beta 2 significantly increased this contraction in a dose-dependent manner, whereas bFGF significantly decreased it. Approximately 30% of cells in the control gels were alpha-SMA positive. TGF-beta 2 significantly increased the alpha-SMA positivity dose dependently, whereas bFGF significantly decreased it. The percent positivity for alpha-SMA and the gel area showed a significant negative correlation. CONCLUSIONS: TGF-beta 2 increased collagen gel contraction and alpha-SMA expression in bovine LECs, whereas bFGF decreased these parameters. Because collagen gel contraction was correlated with alpha-SMA expression, the modulation of LEC contractile activity by growth factors may be related to an effect on alpha-SMA.