Central Visual Field Damage and Parapapillary Choroidal Microvasculature Dropout in Primary Open-Angle Glaucoma

To determine whether microvasculature dropout (MvD) in the parapapillary choroid is related to the presence of central visual field defects in primary open-angle glaucoma (POAG).

Cross-sectional observational study.

Thirty-two POAG patients with an initial parafoveal scotoma (IPFS) within a 10° radius in 1 hemifield and 42 POAG patients with an initial nasal step (INS) within the nasal periphery outside 10° of fixation in 1 hemifield.

The peripapillary choroidal microvasculature was evaluated on en face images obtained using swept-source OCT angiography. Microvasculature dropout was defined as a focal sectoral capillary dropout with no visible microvascular network identified in the choroidal layer. Factors associated with IPFS, compared with INS, were assessed using logistic regression analyses.

Factors associated with IPFS rather than INS.

Microvasculature dropout was observed in 25 of 32 eyes (78.1%) in the IPFS group, but in only 1 of 42 eyes (2.4%) in the INS group (P < 0.001). In logistic regression analyses, only MvD was a significant factor influencing the presence of IPFS. Systemic risk factors such as cold extremities (P = 0.026), migraine (P = 0.044), lower mean arterial pressure (P = 0.037), and lower ocular perfusion pressure (P = 0.024) were associated significantly with the presence of MvD.

The presence of MvD in the parapapillary choroid was a strong predictor for IPFS.