CT Angiography and Ultrasound in Evaluating Blood Vessels Before Liver Transplantation: A Comparative Study / 中国医学影像学杂志

ABSTRACT

Purpose To discuss the value of phase III CT angiography (CTA) and ultrasound in evaluating the preoperative vascular anatomical variation and the lumen patency of the patients with liver transplantation. Materials and Methods The clinical and imaging data of 126 patients with liver transplantation in the First Affiliated Hospital of Zhengzhou University were collected. CT scan in arterial phase, portal venous phase, venous phase and CTAreconstruction and ultrasound examination were performed before surgery. CTA images included volume rendering (VR), maximum intensity projection (MIP), curve plane reformation (CPR), and multi-plane reformation (MPR). The anatomical variations and lumen patency of the hepatic artery, the portal vein system, the hepatic vein and the inferior vena cava were observed. The accuracy of CTA and ultrasound of the evaluation of blood vessels in patients with liver transplantation was compared with the criteria of intraoperative exploration and postoperative pathological results. Results Among 126 patients with liver transplantation, all the hepatic artery lumen was unobstructed, with 98 cases of normal anatomical structure and 28 cases (22.2％) of anatomical variation, including Michel type II 7.1％ (9/126), type III 6.3％ (8/126), type IV 3.2％ (4/126), type V 2.4％ (3/126), type VI 0.8％ (1/126); 2.4％(3/126) of Michel classification was not included. The diagnostic accuracy of CTA for arterial anatomical variations was 100.0％, and the patency diagnosis of the lumen was consistent with the operation, and the anatomical variation cannot be evaluated. In 126 patients, there were 94 cases of portal vein patency, and 32 cases of portal vein embolus, including 21 cases with thrombus and 11 cases with tumor embolus. The diagnostic accuracy of CTA and ultrasound for portal vein embolus was 93.7％ and 96.0％, respectively; and there was no statistical significance (P>0.05). The diagnostic accuracy of them for thrombosis was 96.0％ and 91.3％, respectively; and there was statistical significance (P<0.05). The diagnostic accuracy of them for the tumor thrombus was 97.6％ and 92.1％, respectively; and there was statistical significance (P<0.05), CTA could show the collateral circulation around the portal vein. The diagnostic accuracy of CTA and ultrasound for venous patency was both 99.3％. The diagnostic accuracy of CTA and ultrasound for the anatomy of hepatic venous trunk was 99.2％ and 95.2％, respectively; and there was no statistical significance (P>0.05). Conclusion CTA can accurately evaluate the hepatic artery variation of liver transplantation. It has a high accuracy rate for the qualitative diagnosis of portal vein emboli, and can display collateral circulation. Its overall preoperative diagnostic value is better than that of ultrasound.