Ultrasound examination in the diagnosis of popliteal artery aneurysms.

Popliteal artery aneurysm is a potentially limb-threating lesion which is frequently difficult to diagnose by clinical examination or angiography. The risk of limb loss can best be reduced by early diagnosis. Over the past 5 years we have prospectively evaluated ultrasound examination of the popliteal space in screening patients with clinically suspected popliteal artery aneurysms. One hundred patients who were suspected clinically of having a popliteal artery aneurysm underwent bilateral ultrasound examination of their popliteal fossae. There were 21 patients who had abnormal scans. The problems identified were popliteal artery aneurysm in thirteen patients, popliteal artery ectasia in four patients, Baker's cyst in two patients, thrombosis in one patient and popliteal stenosis in one patient. Eight patients with eleven popliteal artery aneurysms by ultrasound also underwent angiography. Seven of the aneurysms were confirmed, four were missed. All eleven aneurysms were confirmed at operation. In addition, angiography did not demonstrate an aneurysm in any patient with a normal ultrasound. This study confirms that ultrasound examination is a quick, accurate, and non-invasive method of screening for popliteal artery aneurysms.