Popliteal cystic adventitial disease unmasked by intravascular ultrasound.

Cystic adventitial disease (CAD) of the popliteal artery is a rare, nonatherosclerotic cause of intermittent claudication that often mimics peripheral arterial disease, leading to misdiagnosis. We report a 60-year-old man with progressive claudication and duplex evidence of popliteal occlusion. After lesion crossing, intravascular ultrasound (IVUS) revealed a cystic intramural lesion consistent with CAD, prompting surgical repair with complete symptom resolution. A focused literature review identified five IVUS-diagnosed cases, predominantly in middle-aged men. Conventional imaging frequently failed to establish the diagnosis. IVUS reliably identified CAD and guided appropriate management when standard imaging was inconclusive.