Diagnostic value of superficial macular vascular density in detecting early changes of primary open-angle glaucoma

Glaucoma is the leading cause of irreversible blindness worldwide and early diagnosis is essential to preserve the visual health of the population. The objective of this study is to estimate the diagnostic value of macular superficial vascular density in the detection of early changes in primary open-angle glaucoma.

Observational, analytical, and cross-sectional study in 222 eyes (215 participants) and three study groups: negative control (111 healthy subjects), mild glaucoma (55 patients), and positive control (56 patients). CIRRUS™ 5000 technology (version 11.0) was used. To make both eyes equivalent, transposition was performed on the vertical axis in the left eye. The apparent macular vascular density (6 × 6 mm) was obtained by image processing in sectors of interest using the Python algorithm. Areas under the curve with negative control groups and mild glaucoma were calculated.

Both groups were similar in age, sex, systemic diseases and ocular biometry. Vascular densities showed low diagnostic capacity (AUC = 0.56-0.65). The apparent macular vascular densities in outer rings 240-300° and 205-245° (respectively AUC = 0.90 and 0.89) showed better diagnostic capacity (p < 0.05) than neuroretinal ring area, minimum ganglion cell thickness (AUC = 0.82; both) and retinal nerve fiber layer thickness (AUC = 0.79).

Superficial macular vascular density in areas of anatomical interest for glaucomatous damage is the best parameter of optical coherence tomography for the detection of early changes in primary open-angle glaucoma.