Uncommon non-traumatic scalp entities: a pictorial review

Non-traumatic emergent scalp abnormalities are uncommon and may be easily overlooked on routine neuroimaging. However, by nature of its superficial anatomic location, the scalp is frequently the first site of physical abnormality noted by patients. Although scalp pathology is rarely the primary indication for obtaining cross-sectional imaging, the rich vascular supply to the scalp means that this region is commonly linked to disease processes in the skull, intracranial vasculature, and more distant anatomical structures. In this pictorial essay, we present a unique spectrum of scalp lesions encountered on CT and MRI, spanning vascular, hematologic, infectious, and neoplastic etiologies, emphasizing relevant anatomy, characteristic imaging features, and practical diagnostic considerations to help reduce perceptual error.