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Lee and colleagues have recently published the results of a retrospective observational study examining the associations between the rate of change in vascular density and structural parameters of the optic nerve head, macular and retinal nerve fiber layer (RNFL) measured with optical coherence tomography and angiography (OCT/A) in 61 patients with open-angle glaucoma with visual field loss confined to one hemifield to determine if these factors are predictive of the development of a new visual field defect in the unaffected hemifield. These associations were evaluated within separate multivariable cox-proportional hazard models for the OCTA and OCT parameters. These were evaluated separately due to multicollinearity when included in the same model. For structural parameters, they found that a greater rate of change in the RNFL thickness in the normal hemifield, along with greater rates of change in global macular ganglion cell thickness were associated with the development of a new visual field defect (defined by Early Manifest Glaucoma Trial criteria). In the OCTA model, optic nerve head and macular vessel density in the affected and unaffected hemiretinas were associated with the development of a new visual field defect in the perimetrically normal hemifield. Despite the relatively small sample size, this work is additive to several prior case-control studies showing signs of subtle injury in the hemiretina associated with the perimetrically normal hemifield. These results suggest that changes in the vascular and structural parameters maybe a warning sign to alert the clinician of the potential for continued damage. The authors note that there was collinearity between structural and vascular parameters indicating that these parameters were tightly correlated. Thus, it remains unclear if the vascular parameters assessed with OCTA are truly independent of the structural parameters assessed with OCT in the prediction of glaucomatous visual field progression in these patients.