PURPOSE: To evaluate endothelial cell changes following LASIK with residual corneal thickness of less than 250 micro meter. METHOD: We performed noncontact specular microscopy preoperatively, and 1 week, 1, 3, 6, 9 months after surgery to examine 82 eyes which had undergone LASIK. Corneal endothelial density (CD), coefficient of variation of the cell area (CV), and the percentage of hexagonal cells(hexagonality, 6A) were obtained according to the corneal endothelial cell analysis program. Analysis was done according to the parameters such as residual stromal bed thickness, number of laser pulse and percentage of ablated stromal thickness and preoperative spherical equivalent. RESULTS: Changes in CD and CV showed no significant difference throughout the follow-up period after surgery. Hexagonality, however, decreased after surgery. In particular, corneas with residual thickness of less than 235 micro meter or the number of laser pulse over than 400, or ablation more than 30% of stromal thickness showed significant decrease in hexagonality. CONCLUSIONS: This results suggest that LASIK with deep ablation might cause corneal endothelial damages, and at least 235 micro meter or more of residual thickness should be preserved to avoid endothelial damages.
Cornea ; Endothelial Cells ; Follow-Up Studies ; Keratomileusis, Laser In Situ* ; Microscopy

PURPOSE: To evaluate the fundus findings of diabetes mellitus (DM) patients who visited the department of ophthalmology for the first time and to emphasize the importance of early diagnosis and treatment of diabetic retinopathy (DR). METHODS: After 84 DM patients were asked to respond to the questionaire regarding previous medical histories and underwent the general ophthalmological examination, their fundus findings were analyzed and the incidence rates of DR were evaluated according to the prevalence period of DM and the compliance with treatment for DM as well. RESULTS: Motivations of visit to ophthalmology were impairment of visual acuity (46.4%) and requests by medical doctors (35.7%), examinations for other ophthalmologic diseases (13.1%), and mass media (1.2%) in the order. Diagnosis rate of DR in 84 patients who visited our department for the first time was 52.4% and among these, occupying rates of non-proliferative DR and proliferative DR were 47.7% and 52.3% respectively. Incidence rates of DR according to prevalence period of DM were 26.9% in 5 and 10 15 years. Incidence rates of DR according to compliance with treatment for DM were 45%, 50% in regularly and irregularly treated patients respectively. CONCLUSIONS: These results showed that high percentage of DM patients did not take the ophthalmological examination and treatment even though they already had various degree of DR. In these patients, the longer prevalence period of DM, the higher incidence rate of DR, and irregularly treated patients tended to increase the incidence rate of DR compared to regularly treated patients. Thus we emphasize that active public information is required urgently on the importance of early diagnosis and treatment of DR to primary medical doctors to care DM patients as well as DM patients themselves.
Compliance ; Diabetes Mellitus* ; Diabetic Retinopathy ; Diagnosis ; Early Diagnosis ; Humans ; Incidence ; Mass Media ; Ophthalmology ; Prevalence ; Visual Acuity