The Effect of Diffuse Lamellar Keratitis on Visual Acuity and Contrast Sensitivity following LASIK

PURPOSE To evaluate visual outcome and the changes of contrast sensitivity (CS) after diffuse lamellar keratitis (DLK). METHODS Using retrospective chart review, 48 eyes of 25 patients who underwent laser in situ keratomileusis (LASIK) with Visx S4 (VISX Inc., Santa Clara, CA) and M2 (Moria, France) and who were followed for at least six months were included. They were divided into two groups: DLK and non-DLK, by diagnosis of DLK or its absence after LASIK. Postoperative logMAR visual acuities and logCS measured using the VCTS 6500 (Vistech Consultants, Inc., Dayton, OH) were compared with preoperative values in the DLK and non-DLK groups at three and six months after LASIK. RESULTS There was no difference in logMAR visual acuity between the DLK and non-DLK groups until the sixth postoperative month. However, CS was significantly decreased at 12 and 18 cycle/degree compared with preoperative values (p=0.043 and p=0.045, respectively) in the DLK group, whereas CS was significantly increased at 12 cycle/degree in the non-DLK group (p=0.042) at six months. CONCLUSIONS DLK seemed to be strongly associated with a postoperative decrease of CS.