Validity and reliability of the angio-disc protocol for the measurement of vascular density glaucoma

Abstract

Introduction: The glaucoma has been considered one of the leading causes of irreversible blindness worldwide, which is why new technologies aimed at detecting earlier changes in glaucomatous damage are emerging to facilitate more timely diagnosis and monitoring. Objective: To evaluate the validity and reliability of the angio disc protocol for measuring vascular density in individuals over 18 years old with and without a diagnosis of Primary Open-Angle Glaucoma (POAG). Methodology: Retrospective study of diagnostic technology. It included 400 randomized eyes from 400 participants, 251 with POAG and 149 healthy individuals. Results: A reduction in vascular density was observed in the GPAA group compared to the control group. The diagnostic capacity of the angio disc protocol to discriminate healthy and POAG was good in almost all parameters, the best AUC were found in the complete image of the disc AUC 0,94, S:91.2 % and E:84.56 %, peripapillary sector AUC 0,92, S :85,26% and E:84.56% and superior and inferior peripapillary hemifields with AUC 0.92, S: 85.66 % - 86,45 % and respectively. The best cutoff to distinguish between healthy individuals and patients was identified in the complete disk image at a value of ≥ 48.22, with an AUC of 0.94, achieving a sensitivity of 91.24% and a specificity of 84.56%, p = 0.001. The likelihood ratios, LR+ of 5,91 and LR- of 0,10, adequately reinforce the test’s ability to confirm or rule out GPAA. Reproducibility in both groups was > 0.9. A strong positive correlation was obtained when comparing vascular density parameters in relation to those of RLNF by tomography. Conclusions: The angio disc protocol could be considered as a complementary diagnostic tool to the clinical diagnosis of POAG.