Affiliations: Department of Clinical Radiology, University Hospitals – Grosshadern, Ludwig-Maximilians-University, Munich, Germany | Department of Surgery, Klinikum Grosshadern, University of Munich, Munich, Germany
Note: [] Corresponding author: Dr. med. Dirk-André Clevert, Department of Clinical Radiology, University of Munich – Grosshadern Campus, Marchioninistr. 15, 81377 Munich, Germany. Tel.: +49 89 7095 3620; Fax: +49 89 7095 8832; E-mail: Dirk.Clevert@med.uni-muenchen.de.
Abstract: Purpose: This study compared the efficacy of contrast-enhanced ultrasound (CEUS) using a second generation contrast medium versus CT or MRA in the assessment of vascular and biliary complications in postoperative follow-up of liver transplantation. Methods and materials: The study group consisted of 36 consecutive liver transplant recipients who underwent post-transplantation CEUS examination after developing ascites and/or unclear liver function tests. Real time CEUS was performed after a bolus injection of SonoVue® (1.6–2.4 ml, Bracco, Imaging Germany) followed by 10 ml of saline solution. Using contrast harmonic imaging (CHI) technique (Logiq 9, GE) with a 2.5–4-MHz transducer, a low mechanical index was chosen to avoid early destruction of the microbubbles (MI 0.1–0.2). In order to confirm the results, the patients underwent contrast-enhanced MRI or CT. Results: Complications were identified in 16 of 36 patients (44.4%). Five transplants (14%) had hepatic artery thrombosis (n=2) or significant stenosis (n=3). Six transplants (16%) developed portal vein stenosis (n=4) or portal vein thrombosis (n=2). MRI or CT confirmed the findings of the CEUS in all 11 cases. Biliary stricture at the anastomotic site was detected in 5 patients. MR-CP confirmed the findings of all strictures. Conclusion: Due to advances in contrast-enhanced US, vascular and biliary complications in the postoperative period following liver transplantation can be reliably diagnosed non-invasively on the intensive care unit. CEUS shows vascular as well as biliary complications in the postoperative patient with a high degree of accuracy.
