Purtscher Retinopathy

A 46-year-old male with chronic alcohol use disorder is admitted to the ICU with severe acute pancreatitis complicated by SIRS. On hospital day 3, he reports sudden bilateral vision loss with central scotomas. Vital signs show persistent tachycardia and hypotension. Laboratory studies reveal lipase 3200 U/L, triglycerides 900 mg/dL, and calcium 6.9 mg/dL. Dilated funduscopy reveals the findings shown in the diagram. The structure marked **A** — multiple polygonal areas of retinal whitening in the posterior pole — represents the pathognomonic finding of Purtscher retinopathy. Which of the following best describes the pathophysiological mechanism underlying this finding?