Robbins CB, Thompson AC, Bhullar PK, et al. - In this cross-sectional study, researchers used optical coherence tomography (OCT) and OCT angiography (OCTA) to assess changes in the structure and microvasculature of the retina and choroid in eyes of people with Parkinson disease (PD) vs the eyes of age- and sex-matched cognitively healthy control people. This investigation was carried out at the Duke Neurological Disorders Clinic in Durham, NC. In total, 124 eyes of 69 patients with PD (39 men [56.5%]; mean [SD] age, 71.7 [7.0] years) and 248 eyes of 137 control participants (77 men [56.2%]; mean [SD] age, 70.9 [6.7] years) were analyzed. The authors discovered that compared with age- and sex-matched control participants, people with PD had decreased retinal vessel and perfusion densities, increased total choroidal area and choroid luminal area, and decreased choroidal vascularity index. Given the observed population variations in these noninvasive retinal biomarkers, further research into their clinical utility in PD is required.