Heidelberg Retina Tomograph and Frequency Doubling Technology

Abstract

Abstract: : Purpose: To determine if there is a relationship between Heidelberg Retina Tomograph (HRT) parameters and the Frequency Doubling Technology (FDT) indices. Methods: One eye was randomly chosen from 85 patients with primary open angle glaucoma (abnormal visual field and/or abnormal optic nerve and IOP more than 22 mmHg) All the patients were examined with Humphrey Perimeter, program 30-2, SITA standard, FDT, program C 20-5 and HRT. Findings were analyzed using Pearson's correlation coefficient. Results:Among all studied subjects we found a statistically significant correlation (Pearson's r) (p<0.05) between FDT mean deviation and cup shape measure (CSM) (r=-0.41), retinal nerve fiber layer thickness (r=0.33) and retinal nerve fiber layer cross sectionl area (r=0.34), and between FDT pattern standard deviation and volume above reference (0.27), area below reference (r=0.3), cup shape measure (r=0.25), retinal nerve fiber layer thickness (r=-0.36) and retinal nerve fiber layer cross sectionl area (r=-0.34). Using a linear regression model CSM was the most predictive parameter of FDT mean deviation (B=-24.7, SE=5.98; beta=-0.5, p<0.001). Conclusions: The presence of significant correlations between some HRT parameters, such as cup shape measure and visual field indices suggests that both HRT parameters and FDT indices could be good indicators of the degree of the glaucomatous ONH damage.

Keywords: visual fields • optic disc • perimetry