Morphological changes of cornea in iridocorneal endothelial syndrome under the confocal microscopy

Abstract

To evaluate the morphological changes of cornea in iridocorneal endothelial syndrome (ICE) under the examination of in vivo confocal microscopy. The experimental design was retrospective observation case series. Twenty-three eyes of 23 consecutive patients, each diagnosed as ICE, had their both eyes examined with the in vivo confocal microscopy (NIDEK, confoscan 3.0). The images were recorded and analyzed by software NAVIS. Measurements were performed on endothelium density, average endothelial area, the percentage of hexagonal cells and the percentage of endothelium with nuclei, and the ANOVA was done to assess the differences. In vivo confocal microscopy highlighted two main patterns of endothelial changes: "kite-like" and "epithelial-like" abnormal endothelium, characterised by marked hyperreflective nuclei and loss of regularity in cellular size and shape. With the progression of disease, the endothelium density and the percentage of hexagonal endothelial cells decreased, which were (1687.1 +/- 122.6), (1210.6 +/- 168.7), (947.3 +/- 145.2), (856.8 +/- 73.4) cells/mm2 and (51.5 +/- 6.3)%, (39.8 +/- 9.2)%, (32.7 +/- 8.1)%, (24.1 +/- 5.6)% respectively in detail. In contrast, the average endothelial area the percentage of endothelium with nuclei increased, which were (678.3 +/- 56.3), (928.7 +/- 96.2), (1188.5 +/- 72.6), (1337.5 +/- 60.8) microm2 and (12.6 +/- 1.4)%, (56.8 +/- 3.7)%, (78.7 +/- 5.6)%, (84.3 +/- 2.8)%. The differences all had statistical significance (F = 7.158, 7.736, 6.876, 14.452 respectively, P = 0.000). The morphology of keratocyte and endothelium were normal, compared with the contralateral healthy eyes. However, the stromal nerves became thicker and more tortuous with the disease advancement. The application of confocal microscopy indicates that the ICE is characterised by epithelial-like endothelial cells with hyperreflective nuclei. The technique has great potential in diagnosing ICE, especially in evaluating the disease progression.