Usefulness of color Doppler ultrasonography (CDUS) and three-dimensional spiral computed tomographic angiography (3D-CT) for diagnosis of unruptured abdominal visceral aneurysm.

A 52-year-old Japanese man was transferred to our center where screening by means of ordinal ultrasonography and color Doppler ultrasonography revealed an abdominal visceral aneurysm. Although we were unable to confirm the site of this aneurysm by means of ultrasonographic examination, thin-sliced contrast enhanced computed tomography and three-dimensional spiral computed tomographic angiography showed that the aneurysm was situated at the root of the splenic artery. Transcatheter arterial embolization of the aneurysm was performed by metallic coil with occlusion of the main route of the splenic artery because it was technically difficult to embolize the aneurysm alone while preserving the main splenic arterial flow. Angiography of the celiac trunk after transcatheter arterial embolization showed no enhancement of the aneurysm or splenic artery, and superior mesenteric arteriography after transcatheter arterial embolization showed enhancement of the spleen by collateral circulation from the superior mesenteric artery. One year after transcatheter arterial embolization, repeated contrast enhanced computed tomography revealed the enhancement of the spleen, and color Doppler ultrasonography revealed no blood flow in the aneurysm. Color Doppler ultrasonography and 3D-spiral computed tomographic angiography are both useful for diagnosis of a visceral aneurysm, for confirmation of its exact site and form, and for deciding upon a treatment procedure.