Estimation of the Absolute Defects in the Visual Field using OCT in Glaucoma Patients who Cannot Perform a Reliable Test.

Abstract

Background: To find a method to predict the visual field (VF) of glaucoma patients who cannot perform a reliable test by using RNFL thickness and VF of other glaucoma patients. Methods: Seventy eight primary open angle and pseudoexfoliation glaucoma follow-up patients were included in the study. Optic disc OCT measurements and VF analysis were obtained in the same day. Garway-Heats maps made, RNFL sectors matched with pattern deviation 24-2 VF sectors and absolute defects were counted. Regression analysis were made. Equations generated between RNFL thickness and absolute defect number. Correlation analysis were performed for the numbers of absolute defects and the findings.Results: The regression analysis was significantly linear for defect number and RNFL thickness in sectors 3, 4, and 6 (t values were 0.047, 0.04, and 0.001, respectively, p < 0.05). The analysis was nonlinear in other sectors (t values were 1.66, 0.37, 0.14, 0.88, and 0.36, respectively, for sectors 1, 2, 5, 7, and 8, p > 0.05). The linear and nonlinear equations were generated for these sectors. The correlation between the number of absolute defects of the patient and the number we found by using our formulas in VF Sectors of 1,3,4 and 8 there was a strong correlation (r=0.68, r=0.57, r=0.82 and r=0.58 respectively). In VF sectors 3,5,6 and 7 there was a weak correlation (r= 0.22, r= 0.47, r=0.32 and r=0.48 respectively).Conclusion: We think the method that we found is practical to predict the VF of a patient who can not perform it.