Comparison of corneal, endothelial, and anterior segment parameters in eyes with and without pigment dispersion.

Background: To evaluate the differences of central corneal thickness (CCT), corneal endothelial cell morphology, and biometric parameters of the anterior chamber and iridocorneal angle in pigment dispersion syndrome (PDS), pigmentary glaucoma (PG), primary open-angle glaucoma (POAG), and healthy group.

Methods: Twenty- three eyes in the PDS group, 39 eyes in the PG group, 33 eyes in the POAG group, and 45 eyes in the healthy control group were included in this cross-sectional retrospective study. Corneal endothelial cell density, the coefficient of variation in the cell area, hexagonality, and central corneal thickness (CCT) were obtained by specular microscopy (CEM 530, NIDEK, Japan). Anterior chamber depth (ACD), iridocorneal angle parameters and CCT were measured by anterior segment optical coherence tomography (AS-OCT) (Visante OCT, Carl Zeiss AG, Germany).

Results: The mean CCT via specular microscopy (SM-CCT) was measured at the thinnest value in the PG group (531.20 ± 34.91 µm) and the thickest in the control group (569.13 ± 37.52 µm). CV value was higher in PG (34.65 ± 6.84) and POAG group (34.27 ± 9.93) and lower in control group (28.82 ± 5.18) (p = 0,005). The mean AS-OCT-CCT was the thinnest in the PG group (513.61 ± 39.94 µm), and the thickest in the control group (547.04 ± 36.72 µm) (p = 0.001). All parameters of the iridocorneal angle were larger in the PDS and PG groups (p < 0.001). In the correlation analysis of the glaucomatous eyes, a negative correlation between the C/D ratio and SM-CCT and AS-OCT-CCT (p = 0.037, p = 0.017, respectively) and a positive correlation between the pRNFL thickness and AS-OCT- CCT (p = 0.002).

Conclusion: CCT values obtained with both SM and AS-OCT were found to be significantly thinner in PG cases. CV, which is the measure of polymegatism, was found to be significantly higher in PG cases.