PTGS2 and Alzheimer disease: This “Opinion paper” will comment on current trends in our understanding of specific amyloidogenic and pro-inflammatory changes in the human primary visual cortex and retina as AD advances with particular reference to: (i) the expression of the pro-inflammatory marker cyclooxygenase-2 (COX-2); (ii) the appearance and aggregation of Aβ 42 peptides; (iii) epigenetic mechanisms involving microRNA (miRNA) signaling that appear to be associated with disease propagation; and (iv) how direct and non-invasive analysis of the retina may help to detect and diagnose AD.