Confocal microscopic characteristics of stage of 1 to 4 diffuse lamellar keratitis after laser in situ keratomileusis

Purpose: To evaluate 4 stages of diffuse lamellar keratitis (DLK) after laser in situ keratomileusis using confocal microscopy. Setting: Department of Ophthalmology, Johann Wolfgang Goethe-University, Frankfurt am Main, Germany. Methods: This retrospective study comprised 17 eyes (15 patients): 11 cases of stage 1 DLK, 5 cases of stage 2, 1 case of stage 3, and 2 cases of stage 4. All eyes were examined by slitlamp biomicroscopy and confocal microscopy. Results: In all cases of stage 1 and 2 DLK, confocal microscopy showed infiltration of inflammatory cells into the flap stroma and the interface. The density of the infiltrates and the number of cells varied within the stage 1 corneas; all stage 2 corneas had dense infiltrates. In the eye with stage 3 DLK, an aggregation of presumed cell remnants was noticed. In the stage 4 cases, there was no active inflammation but stromal folds and numerous activated keratocytes were detected. Conclusions: Confocal microscopy showed differences in the appearances of the DLK groups. There were similarities in the features of stages 1 and 2. Only stages 1 and 2 represented active inflammation, whereas stages 3 and 4 showed the result of accumulation and decay of the inflammatory cells. (C) 2002 ASCRS and ESCRS.