Abstract
Abstract: :
Purpose: The features of morphology and density of keratocytes in healthy corneas provide a baseline to evaluate reaction of stromal tissue to corneal wounding. The majority of previous studies examined the density of keratocytes in healthy corneas using rabbit model. This study investigated morphology and density of keratocytes across the cornea in a feline model using confocal microscopy. Methods: Ten eyes of 5 cats with an age ranging from 1 to 2 years were used in this study. The cornea of all eyes was confirmed normal with slit–lamp biomicroscopy prior to confocal microscopy. The animals were evaluated by confocal microscopy (Confoscan 2, Fortune Technologies) under general anaesthesia. The digital images were acquired from the central cornea and the images from anterior (> 300 µm from endothelium), middle (150 – 300 µm from endothelium) and posterior cornea (< 150 µm from endothelium) were selected for analysis of morphology, density and size of keratocytes. Results: Cell size of keratocytes was similar across the anterior to posterior cornea in all eyes examined (n = 10). However, cell morphology changed from flat or elongated to round when observed from the posterior to anterior stroma. In addition, the keratocytes looked more homogeneous towards anterior stroma. There was a gradual increase in keratocyte density from posterior to anterior stroma, which is different from that in human stroma where high density of keratocytes only occurs in the superficial stroma adjacent to the Bowman’s layer. The mean density of keratocytes (Table 1) between the anterior and posterior feline stroma was highly significantly different (p < 0.001). Table 1:
Conclusion: Both morphology and density of keratocytes in a healthy feline cornea vary with different stromal layers. These features should be considered to avoid misleading interpretation during an in vivo or histological assessment of wounded corneas.
Keywords: cornea: stroma and keratocytes • cornea: stroma and keratocytes • cornea: stroma and keratocytes