Imaging nodules within cirrhotic liver: how do I do it?

Cirrhosis is a chronic liver disease characterized by the presence of diffuse parenchymal necrosis, reactive fibrosis and nodular regeneration. These regenerative nodules may evolve into dysplastic nodules and finally nodules of hepatocellular carcinoma (HCC). Improved survival of cirrhotic patients with HCC depends on eligibility to liver transplantation. The purpose of this paper is to review the imaging features of liver nodules within cirrhotic liver and to propose the imaging strategies when considering the possibility of liver transplantation.     

Innominate artery involvement in type iv Ehlers-Danlos syndrome

We report two cases of innominate artery involvement in patients with Ehlers-Danlos syndrome. In the first patient, spontaneous dissection of the innominate artery was treated successfully. In the other, the patient died of spontaneous rupture of the innominate artery in the early postoperative course after operation for aneurysm of the celiac artery. Arterial complications occurring in Ehlers-Danlos syndrome are rare but pose difficult diagnostic and therapeutic problems for the vascular surgeon due to arterial wall fragility.Presented at the Annual Meeting of the Société de Chirurgie Vasculaire de Langue Française, May 18–19, 1990, Nancy, France.     

Evaluation of noninvasive diagnostic criteria for hepatocellular carcinoma on pretransplant MRI (2010): correlation between MR imaging features and histological features on liver specimen

PurposeTo validate the 2010 diagnostic criteria from the American Association for the Study of Liver Diseases (AASLD) for hepatocellular carcinoma (HCC) on MRI using the surgical liver specimen as a gold standard.Patients and methodsA total of 21 liver transplant recipients were retrospectively included. Each underwent surgery because of HCC between January 2007 and January 2008. Pre-transplant MRI was performed on a 1.5 Tesla MR unit. The T1W and T2W signal and kinetic contrast enhancement were correlated for each lesion with the surgical specimen. Lesion diameters between MRI and specimen were compared (Spearman). A multivariate model was created (R statistics software package) to predict the presence and grade of tumor differentiation (WHO, Edmonson Steiner).ResultsA total of 71 nodules were detected at histology, including 54 HCC (mean size: 25.3 mm) compared to 68 on MRI. There was moderate agreement (r = 0.58, P < 0.001) between the maximum lesion diameters measured on MRI and at histology. Wash-out on MRI provided an accuracy of 75 % for the detection of HCC (sensitivity = 75 %, specificity = 76 %). Adding T2W hyperintensity to the AASLD criteria increased the sensitivity of MRI from 70.3 % to 77.7 % for the diagnosis of HCC and from 67.6 % to 79 % for nodules less than 20 mm in diameter, without affecting specificity. On multivariate analysis, wash out as a single variable was significantly associated with a diagnosis of HCC (P < 0.01, odds ratio 12.0, CI 95 % [2.6–55.5]). T1W hyperintensity (P = 0.04, odds ratio 5.4) and loss of signal on opposed-phase images (P = 0.02, odds ratio 9.2) were predictive of good differentiation.ConclusionOn MRI, the AASLD criteria or presence of wash out within a liver nodule in patients with underlying chronic hepatocellular disease are suggestive of tumoral transformation. The addition of T2W hyperintensity to the AASLD criteria increases the detection of HCC, especially nodules smaller than 20 mm.     

Liver magnetic resonance diffusion weighted imaging: 2011 update

Diffusion-Weighted-Imaging (DWI) assesses proton motion on a cellular scale. Owing to recent instrumentation developments, diffusion sequences are now routinely used for liver imaging. This review will go through the physical principles that underlie this technique, and then highlight up-to-date liver applications including quantification of liver fibrosis, focal lesions detection and characterization, and therapy response monitoring.