Imaging and clinical findings in segmental arterial mediolysis (SAM)

Segmental arterial mediolysis (SAM) is an uncommon, non-atherosclerotic, non-inflammatory arteriopathy that tends to affect the medium-sized splanchnic branches of the aorta along with renal, carotid, cerebral, and coronary arteries. The clinical presentation ranges from asymptomatic to severe, life-threatening intra-abdominal hemorrhage and shock. SAM overlaps clinically and radiologically with other inflammatory vasculitides. This article describes the pathologic–radiologic correlation, imaging findings, and the management of the disease. Radiologists should be familiar with this disease entity as imaging plays a crucial role in the diagnosis.