The effect of the YK lens in keratoconus.

PURPOSE: To report the clinical results of the use of the YK contact lens (Lucid Co., Seoul, Korea) for keratoconus. METHODS: One hundred and twenty nine keratoconic eyes were fitted with a YK lens which has one base curve and three peripheral curves. A light feather touch fluorescein pattern was obtained based on topographic indices. Visual acuity, comfort, mean wearing time, and ocular tissue changes were evaluated. Mean follow up was 17.5 +/- 13.8 months (range 6-75). RESULTS: One hundred and twenty six (97.6%) eyes tolerated the contact lenses. A total of 94.5% of the eyes achieved a visual acuity of 20/40 or better (average 0.79 +/- 0.21), and flatter base curve radius (BCR) was related to better visual acuity. One hundred and seventeen (90.7%) eyes reported that the lenses were comfortable. Mean wearing time was 12.1 h per day (range 4-18). Changes in keratometric values were not significant between baseline and final follow-up visit. CONCLUSIONS: The YK lens can provide successful visual outcome, with comfort, and no significant influence on the progression of keratoconus.

Inhibitory effects of bevacizumab on angiogenesis and corneal neovascularization.

BACKGROUND: To evaluate the inhibitory effects of bevacizumab (Avastin) on angiogenesis using cultured human umbilical vein endothelial cells (HUVECs) in vitro and on corneal neovascularization by subconjunctival injection of bevacizumab in vivo. METHODS: After the HUVECs were exposed to different concentrations of bevacizumab stimulated with VEGF (10 ng/ml) for 2, 6, and 24 hours, cellular-activity-like proliferation, migration and tube formation were assessed. Subconjunctival injection of bevacizumab (2.5 mg/0.1 ml) was performed after corneal chemical burn injury. Then the cornea was evaluated by biomicroscopy, fluorescein angiography, and light microscopy. RESULTS: The inhibitory effects of bevacizumab on VEGF-induced HUVECs proliferation showed a dose-dependent response for 2 and 6 hours, but all groups were effectively inhibited regardless of the concentration of bevacizumab for 24 hours. The inhibitory effects of bevacizumab on the migration of VEGF-induced HUVECs showed a time- and dose-dependent response. The inhibitory effects of bevacizumab on VEGF-induced HUVECs tube formation showed a dose-dependent response only for 24 hours. On days 3 and 8 after the subconjunctival injection, bevacizumab-treated eyes showed less neovascular growth than BSS-treated eyes in biomicroscopic, fluorescein angiographic, and light microscopic findings in vivo. CONCLUSIONS: Bevacizumab effectively inhibits angiogenesis and corneal neovascularization, and could be used as a inhibitor of corneal neovascularization in the future.

Cellular toxicity of calf blood extract on human corneal epithelial cells in vitro.

PURPOSE: To investigate the biologic effects of the calf blood extract on corneal epithelial cells in vitro. MATERIALS AND METHODS: The effects on corneal epithelial cells were evaluated after 1, 4, 12, and 24 h of exposure to various concentrations of calf blood extract (3, 5, 8 and 16%). The MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide) assay was performed to measure levels of cellular metabolic activity. The lactate dehydrogenase (LDH) assay was performed to determine the extent of cellular damage. Cellular morphology was examined using phase-contrast microscopy. The scratch wound assay was performed to quantify the migration of corneal epithelial cells. RESULTS: At the 3 and 5% concentrations of calf blood extract, MTT values were similar to those observed in the control group. However, at a concentration of 8 and 16%, cellular metabolic activity was significantly decreased after 4 h of exposure to calf blood extract. After 12 h of exposure to 8 and 16% concentrations of calf blood extract, LDH activity and cellular morphological damage to the corneal epithelial cells were significantly increased. There was no evidence of cellular migration after 12 h exposure to 5% or higher concentration of calf blood extract because of cellular toxicity. CONCLUSIONS: Compared with normal corneal epithelial cells, the cellular activity was decreased, and toxicity was increased after over 12 h of exposure to more than 5% concentration of calf blood extract. Further clinical studies will be necessary to determine the optimal concentration and exposure time for the topical application of eye drops containing calf blood extract.

Clinical features of ocular trauma in emergency department.

This study analyzed a hospital-based study to investigate the incidence and clinical features of ocular traumatic emergencies in Korea. Over a 6-year period, 1809 patients with ocular traumatic emergency each individually underwent clinical study including subject characteristics, type of ocular emergency, disease severity, etiology of ocular trauma, injury location, cause of decreased visual acuity, management of ocular injury, and final visual acuity. The homogeneity of each finding of the clinical features of ocular traumatic emergency was tested by an X2 test at a 95% level of certainty. During follow-up periods ranging from 3 days to 23 months (mean 2.0 months), the 1809 patients with ocular traumatic emergency, 1183 males (65.4%) and 626 females (34.6%), were studied. The incidence of ocular emergencies peaked in the third decade of life, irrespective of gender (P < 0.05). Corneal abrasion was the most common etiology among 1,552 (85.8%) closed injuries, and corneal laceration among 257 (14.2%) open injuries (P < 0.05). There were 542 cases (30%) of severe ocular injury, such as penetrating ocular injury, blow out fracture, and intraocular foreign body (IOF), and 1267 (70%) of less severe ocular injury, such as superficial ocular injury or contusion. The most common etiology of severe ocular injury was penetrating ocular injury, and that of less severe injury was corneal injury (P < 0.05). The main causative activity of ocular injuries was work in 631 cases (34.9%), assault in 398 (22.0%), play in 278 (15.4%), traffic accidents in 145 (8.0%) and sports in 128 (7.1%). Five hundred and fifty-four cases (32.5%) underwent surgical intervention. There was an improvement of visual acuity in 502 cases (70.1%), no change in 122 (17.0%), and worsening in 92 (12.9%). We suggest that preventive educational measures be instigated at workplaces to reduce the incidence of ocular traumatic emergency, especially severe ocular injury.

Intraocular pressure and influencing systemic health parameters in a Korean population.

AIM: To evaluate the relationship between intraocular pressure (IOP) and systemic health parameters such as age, gender, body mass index (BMI), total cholesterol, high density lipoprotein (HDL), and triglyceride (TG) in a Korean population. MATERIALS AND METHODS: A total of 30,893 healthy subjects underwent automated multiphasic tests, including non-contact tonometry, automated perimetry, fundus photography, and blood samplings for total cholesterol, HDL, and TG. Seven age groups were divided by decades ranging from 20 to 29 years to 80 + years. The association between IOP and BMI, plasma lipid profiles was examined using cross-sectional analysis. RESULTS: The mean age of subjects was 47.7 years. The mean IOP of subjects was 15.4 ± 3.2 mmHg for both eyes. The mean IOP of men was significantly higher than women ( P = 0.000). By multiple linear regression analysis, IOP was positively associated with gender (male), BMI, total cholesterol, and TG and negatively associated with age ( P = 0.000). BMI, total cholesterol, and TG had significantly positive correlations with IOP after adjusting for age, gender, and other variables which can influence the IOP ( P = 0.000). CONCLUSIONS: In a Korean population, the mean IOP, total cholesterol, TG, and BMI values of men were higher than women. IOP was found to increase with total cholesterol, TG, BMI, and to decrease with only age regardless of sex.

Subperiosteal hematoma after surgical treatment for subarachnoid hemorrhage.

After the surgical treatment for subarachnoid hemorrhage, computed tomography and magnetic resonance imaging clearly demonstrated a fracture in the medial wall of the left orbit and a superonasal subperiosteal hematoma. Removal of the subperiosteal hematoma and correction of the fracture were successful. Subperiosteal hematoma is an unusual complication after inadvertent neurosurgical manipulation.