Abstract
Abstract: :
Purpose: The corneal endothelium plays an important role in maintenance of corneal clarity by regulating the water content of the stroma. Although specular microscopy allows evaluation of the morphology of the corneal endothelium, it has not been possible clinically to assess endothelial function other than by measurement of corneal thickness. The basal cell layer of the corneal epithelium yields a high–intensity image in confocal microscopy. We therefore measured the intensity of the basal cell layer of the corneal epithelium in confocal microscopic images and calculated the basal cell layer (BCL) index by computer–assisted analysis in order to determine whether this parameter might reflect corneal endothelial function. Methods: A total of 14 eyes of 11 cataract patients (mean age, 73.0 years) was subjected to cataract surgery (phacoemulsion–aspiration) and intraocular lens implantation without surgical complications. Confocal microscopy was performed preoperatively and postoperatively. The intensity of the images of the basal cell layer of the epithelium at the center of the cornea was determined with a newly developed intensity measurement program. We defined the BCL index as the average intensity of the basal cell layer in five images. The anterior chamber reaction was also determined by a laser flare meter and corneal thickness was measured. Results: The coefficient of variation of the BCL index was 5.46 ± 3.90% (mean ± S.D.) for all 14 eyes. The mean BCL index was 107.4 ± 8.3 before surgery and 125.2 ± 19.5, 114.9 ± 10.1, 105.6 ± 11.5, 108.8 ± 15.1, and 111.6 ± 15.8 at 1, 3, 5, 7, and 14 days postsurgery, respectively. The mean BCL index 1 day after surgery was significantly (P < 0.02) increased compared with the preoperative value. The changes in the BCL index correlated well with those in the anterior chamber flare value and in corneal thickness after surgery. Conclusions: The BCL index appears to change in parallel with corneal endothelial function and might therefore prove clinically useful as a parameter for assessment of such function
Keywords: cornea: endothelium • imaging/image analysis: clinical • clinical (human) or epidemiologic studies: systems/equipment/techniques