Corneal Properties in Primary Open Angle Glaucoma Assessed Through Scheimpflug Corneal Topography and Densitometry

Abstract

Purpose: To compare corneal topography and densitometry measurements in patients with primary open angle glaucoma (POAG) and healthy subjects. Patients and Methods: 200 eyes of 75 patients with POAG and 125 healthy controls underwent corneal topography and densitometry (Oculus Pentacam HR). The data compared in the two groups were: anterior chamber angle (ACA), depth (ACD) and volume (ACV), keratometry (K minimum, K maximum and K mean), central corneal thickness (CCT), central anterior elevation (CAE), anterior elevation apex (AEA), maximum anterior elevation (MAE) and posterior elevation apex (PEA). Densitometry measurements were made at three depths on a 12▒mm-diameter circle divided into 4 concentric rings (0-2▒mm, 2-6▒mm, 6-10▒mm and 10-12▒mm). The diagnostic capacity of the corneal variables was assessed through the areas under the receiver operator characteristics (ROC) curve (AUC). Results: The corneal density of practically all depth layers and total corneal density were significantly higher in the POAG than control group (P<0.05). Total corneal density was positively correlated with age (r=0.623; P<0.001) and also showed a good diagnostic capacity for glaucoma (AUC=0.617; IC 95% [0.541-0.697]; P<0.001). In a multiple linear regression designed to assess its relationship with age, gender, CCT and Km, age emerged as a significant confounder both in controls (coef. 0.315; P<0.001; 95% CI [0.246-0.384]) and patients (coef. 0.370; P<0.001; 95% CI [0.255-0.486]). Conclusion: Corneal densitometry measurements showed a good diagnostic capacity for POAG suggesting this type of examination could have clinical applications in the diagnosis and management of glaucoma.