Aneurysms: popliteal and visceral artery aneurysms.

Popliteal artery aneurysms (PAAs) occur in approximately 1 of every 100 men ages 65 to 80 years. They can occur bilaterally, and abdominal aortic aneurysm is simultaneously present in 50% of cases. Therefore, patients with PAAs should undergo ultrasonography to exclude abdominal aortic aneurysms and contralateral PAAs. The main risk of PAAs is thrombus/embolus formation causing lower limb ischemia. Any symptomatic PAA or PAA containing a thrombus should be repaired regardless of size. Asymptomatic PAAs should be considered for repair if the diameter is 2 cm or greater. Visceral artery aneurysms are rare and typically are diagnosed incidentally during imaging for other conditions. The most common is splenic artery (SA) aneurysm, but aneurysms also occur in hepatic, mesenteric, celiac, and other arteries. Although uncommon and typically asymptomatic, SA aneurysms are significant because of rupture risk. Current recommendations are that SA aneurysms 2 cm or larger should be repaired. SA aneurysms of any size should be repaired in pregnant women and women of childbearing age because of the high maternal (75%) and fetal (95%) mortality rates associated with rupture. Superior mesenteric artery aneurysms should be repaired, regardless of size because of rupture risk. Other visceral artery aneurysms typically can be monitored and repaired if they reach 2 cm in diameter.