Correlation between anterior chamber angle status and limbal stem cell deficiency in primary angle-closure glaucoma.

PURPOSE: To investigate the correlation between the opening and closing states of anterior chamber angle (ACA) and the density of limbal epithelial basal cells (LEBCs) in subjects with primary angle-closure glaucoma (PACG).

DESIGN: Cross-sectional observational study.

METHODS: A total of 54 eyes of 29 patients diagnosed with PACG were included in the study. 54 eyes from normal subjects were included as control. Automatic evaluation system for ultrasound biomicroscopy images of anterior chamber angle was used to assist ophthalmologists in identifying the opening or closing state of ACA, and the in vivo confocal microscopy (IVCM) was used to evaluate the density of LEBCs in different directions.

RESULTS: 1. The average density of LEBCs in the superior, inferior, nasal and temporal limbus of the eyes in the PACG group was lower than that in the control group, and this pattern did not align with the density distribution observed in the control group. 2. In the early, moderate and advanced PACG, the density of LEBCs corresponding to the closed angle was lower than that in the control group (P<0.05). Compared with the density of LEBCs corresponding to the closed angle and the open angle, the closed angle of PACG in the early, moderate and advanced stages was less than that in the open angle (P<0.05 in the early and moderate stages; advanced stage P>0.05). 3. The basal cell density was processed by dimensionless analysis. In the data calculated by averaging and minimizing, both closed angle dimensionless values were smaller than the open angle (P<0.05). 4. Comparative analysis was conducted among the normal, open-angle, and closed-angle conditions in the superior, inferior, nasal, and temporal limbus. In the early stage of PACG, significant differences were observed in 4 limbal regions (P<0.05), while in the moderate PACG stage, this difference was noted in 3 limbal regions (P<0.05). In advanced PACG, 2 limbal regions exhibited significant differences (P<0.05). These findings suggest that during the early PACG stage, angle closure is the predominant influencing factor on LEBCs density, while in the advanced stage, the decrease in density is attributed to a combination of angle closure and the natural progression of the disease.

CONCLUSION: There is a significant correlation between anterior chamber angle status and LEBCs. Advanced PACG and angle closure should be highly suspected of the occurrence of limbal stem cell deficiency (LSCD).