Fig. 3.

Another case of celiac artery compression syndrome (CACS) with inferior pancreaticoduodenal artery aneurysm. In a 51-year-old woman, accidental 22-mm abdominal visceral aneurysm was observed (a), and pancreaticoduodenal artery aneurysm resection was performed. Despite “arterial compression hook sign”-positive (b), the expiration peak systolic velocity (PSV) has a low flow velocity with systolic spikes without diastolic flow (c). PSV at different respiratory positions. c) expiration PSV (106 cm/s); d) inspiration PSV (493 cm/s). Unlike typical CACS, when a blood vessel is nearly occluded during expiration, peak systolic velocity rises during inspiration rather than expiration. Such a reverse phenomenon occurs when the celiac artery is compressed very strongly and almost occluded. SMA Superior mesenteric artery, CA celiac artery, Ao aorta, An aneurysm