In-vivo Confocal Microscopy of the Corneal Endothelium in Young Adults With Down's Syndrome

Abstract

Purpose: : To examine the corneal endothelial cells with in-vivo confocal microscopy in Down’s syndrome and normal control subjects.

Methods: : Six well-functioning young adults with Downs’s syndrome (mean age 25.7 years, range 20-29) and nine control subjects (mean age 23.0 years, range 20-28) were examined with in-vivo confocal microscopy (Nidek ConfoScan3). None of the examined subjects had keratoconus. Manual, variable-frame analysis of the endothelial cells was performed and compared between the two groups.

Results: : Mean density of endothelial cells was 2654 and 2897 cells/mm² in the Down’s syndrome group and the control group, respectively (p=0.12). Mean endothelial cell area in the Down’s syndrome patients was 397 µm²/cell, while it was 366 µm²/cell in the controls (p=0.14). When comparing mean cell area in the total number of cells counted, the difference between the Down’s syndrome group and the control group was highly statistically significant (p<0.001). Mean coefficient of variation (CV) of mean cell area (polymegatism) was 0.29 in both groups. The mean percentage of hexagonal endothelial cells was 66% among the Down’s syndrome patients and 61% in the control group (p=0.19).

Conclusions: : The mean size of the endothelial cells was increased in the Down’s syndrome group compared to the controls. There was no difference in the frequency of polymegatism or pleomorphism in the two groups.

Keywords: cornea: endothelium • microscopy: confocal/tunneling