Assessment of Liver Transplant Grafts on Gadoxetic Acid Enhanced-MRI in Pediatric Patients

Case Series

Austin J Radiol. 2017; 4(1): 1066.

Assessment of Liver Transplant Grafts on Gadoxetic Acid Enhanced-MRI in Pediatric Patients

Gungoren FZ1,2, Hodge JC¹, Hayat A1,3, Bastati N1, Gehan M4 and Ba-Ssalamah A1*

¹Department of Biomedical Imaging and Image-guided Therapy, Medical University Vienna, Austria

²Department of Radiology, Istanbul Medipol University, Turkey

³Department of Radiology, IBN Sina Hospital, Kuwait

4Department of Pediatrics and Adolescent Medicine, Medical University Vienna, Austria

*Corresponding author: Ba-Ssalamah A, Department of Biomedical Imaging and Image-guided Therapy, Medical University Vienna, Währinger Guertel 18-20A- 1090, Vienna, Austria

Received: March 28, 2017; Accepted: May 15, 2017; Published: May 25, 2017


A wide spectrum of neonatal and pediatric liver diseases can be successfully treated by liver Transplantation (LT). During the last sixty years, refined diagnostic and surgical techniques, improvements in perioperative care, and the advent of better immunosuppressive medications have established LT as a viable treatment option for acute and chronic liver failure in children. As clinical and laboratory findings of LT complications are often nonspecific, imaging tests play a major role in both diagnosis and guidance of therapeutic interventions. In this article, we wanted to emphasize the potential role of gadoxetic acid-enhanced MRI in the evaluation of liver transplant grafts in the pediatric population.We included seven pediatric patients who underwent gadotexic acid-enhanced MRI with different operative procedures.

Our series suggests potentially added value of gadoxetic acid for the evaluation of morphologic LT complications, i.e., vascular, biliary, or anastomotic obstruction, as well as parenchymal disorders, including global or segmental (for example, auxiliary LT) hepatobiliary dysfunction.

Gadoxetic acid-enhanced MRI showed its ability to depict morphological or anatomical postoperative complications, including vascular occlusion or biliary strictures. Contrary to the conventional imaging modalities or nuclear medicine exams, gadoxetic acid-enhanced MRI can also provide us simultaneously with global and segmental functional information, with high spatial resolution and no radiation exposure.

In this article, we show our imaging experience using gadoxetic acidenhanced MRI in the evaluation of LT in children, and its superiority to US, CT, and conventional MRI, by providing anatomic and functional data about the graft.

Keywords: MRI; Contrast material; Liver; Pediatric

Case Presentation

Liver Transplantation (LT) is the only curative treatment of acute or chronic liver failure in pediatric patients [1]. However, contrary to adults, pediatric LT may be performed using a variety of different techniques, according to the indication, graft availability and donorrecipient size match [2]. In kids, a subtotal or total liver graft may be transplanted from a living or deceased donor, respectively. Furthermore, the graft can either replace or be added to the native liver. In the latter case, the so-called auxiliary LT supports the child until his native liver recovers from acute failure [3]. To interpret post-operative images, the radiologist must know the type of LT procedure done, as the complications and prognosis vary with the type of surgery. Although US, and less often angiography and ERCP, have been used to study morphologic complications of the graft post-operatively, until recently, there has been no non-invasive, operator-independent imaging modality to do this [4]. CT remains less than ideal, in the pediatric population, due to its ionizing radiation. Conventional MRI, unlike gadoxetic acid enhanced-MRI, gives only morphologic information, i.e. pertaining to vascular and biliary anastomoses [5]. Using gadoxetic acid enhanced-MRI, however, we are able to obtain information regarding liver function, too. Furthermore, using this specific Contrast Media (CM), we can detect global and segmental parenchymal dysfunction due its unique pharmacokinetic properties [6]. This CM is used routinely in adults and off-label in children, for the work-up of focal liver lesions, diffuse liver diseases and hepatobiliary disorders, including the evaluation of LT grafts [7]. Through the following case series, we illustrate the use of gadoxetic acid enhanced-MRI in a variety of post-op LT patients with a broad spectrum of complications demonstrating its morphologic and functional properties.

Case 1

A 14-year-old boy with known Ulcerative Colitis (UC), Primary Sclerosing Cholangitis (PSC) and Autoimmune Hepatitis (AIH) was brought to the ED with abdominal pain. Laboratory tests demonstrated severe elevation of cholestatic liver function parameters. MRCP performed preoperatively showed a “string of pearls”, i.e. irregularity of the bile duct caliber, very characteristic of PSC (Figure 1a). Gadoxetic acid enhanced-MRI showed diminished uptake and absent excretion of CM in the liver on HBP images consistent with end-stage chronic liver disease (Figure 1b,c). Soon thereafter, he received a whole liver graft, i.e. orthotopic LT. Fivemonths post-op MRI showed good uptake and timely excretion of CM in the HBP (Figure 1d,e). Laboratory tests at both time points also confirmed normal liver function.