In Vivo Confocal Microscopy of Keratic Precipitates in Fuchs Heterochromic Uveitis Syndrome

Abstract

In vivo confocal microscopy (IVCM) enables large-field in vivo examination of the corneal endothelium and corneal precipitates. Keratic precipitates (KP) are prominent features of Fuchs Heterochromic uveitis syndrome (FHUS). The aim of this study was to investigate the effect of KP on the corneal endothelium. Eight patients with clinically diagnosed FHUS and KP between July 2007 and May 2008 underwent slit lamp examination and IVCM. KP (shape, area), endothelial cell count and percentage of hexagonal cells were measured and compared with an age-matched control group and with not affected healthy contralateral eyes. The age of participants ranged between 26 and 67 years. KP had a diameter ranging between 37 to 217 microm (mean 137 microm) with an average area of KP of 5630 microm (2). The mean endothelial cell count in the study group was 2541 +/- 299 cells/mm (2), 2722 +/- 312 cells/mm (2) in the control group (p = 0,18) and 2397 +/- 192 cells/mm (2) in not affected contralateral eyes (p = 0.17). The percentage of hexagonal cells was 59.1 % in FHUS study group and 69.1 % in the control group (p = 0.0002) and 68.6 % in not affected contralateral eyes (p = 0.0495). KP in FHUS cause a focal damage of endothelial cells reflected in a decreased percentage of healthy hexagonal cells. The degree of endothelial cell damage seems to be low as it does not lead to a significant reduction in the endothelial cell count.