Feasibility of transcolonic and transgastric abdominal vascular ultrasound

Abstract

Abdominal vascular ultrasound is hampered by tissue attenuation. To improve imaging, the feasibility of real-time color Doppler transcolonic and transgastric abdominal vascular ultrasound was evaluated. A monoplane 5 MHz transesophageal probe was inserted via a proctoscope in five patients with normal colons. At 25 cm (end of proctoscope), the aortic bifurcation and iliac arteries were dynamically imaged with high resolution. In three patients undergoing abdominal surgery, the surgeon grasped the probe and advanced it further through the descending to the transverse colon to examine further vascular structures. High resolution two-dimensional imaging and color Doppler flow were obtained from the abdominal aorta, the origins and proximal portions of the superior mesenteric artery, and the renal and the inferior mesenteric arteries. Additionally, the inferior vena cava, left renal vein, and portal system were imaged. All vascular structures imaged were within 3 cm of the probe. In two additional patients undergoing abdominal surgery and transesophageal echocardiography, the surgeon grasped the probe in the stomach and placed it on various vascular structures. The results were similar and the celiac trunk was also imaged. This technique, when integrated with fiberoptics for guidance, could provide a method for abdominal vascular ultrasound with less tissue-imposed attenuation, providing high resolution imaging and allowing additional structure recognition. This has potential applications for studying patients with disease of the abdominal aorta or its branches.