Liver Graft Volume Estimation by Manual Volumetry and Software-Aided Interactive Volumetry: Which is Better?

PURPOSE: Estimation of graft volume is critical in living donor liver transplantation (LDLT). In this study, we aimed to evaluate the accuracy of software-aided automated computer tomography (CT) volumetry in the preoperative assessment of graft size for LDLT and to compare this method with manual volumetry. MATERIALS AND METHODS: Forty-one donors (27 men; 14 women) with a mean age in years ± standard deviation (28.4 ± 6.6) underwent contrast-enhanced CT prior to graft removal for LDLT. A liver transplant surgeon determined the weights of liver grafts using automated 3-dimensional volumetry software, and an abdominal radiologist specializing in liver imaging independently and blindly used the commercial interactive volumetry-assisted software on a viewing workstation to determine the liver volume on CT images. Both results were then compared to the weights of actual grafts obtained during surgery. Intraclass correlation coefficients were used to assess the consistency of numerical measurements and Pearson correlation coefficients were calculated to detect a linear relationship between numerical variables. To compare correlation coefficients, z scores were used. RESULTS: Regarding the right and left lobe graft volume estimation by the surgeon, there was a positive correlation between the results and actual graft weight (r = 0.834; P = .001; and r = 0.587; P = .001, respectively). Likewise, graft volume estimation by the radiologist for the right and left lobe was also positively correlated with the actual graft weight (r = 0.819; P = .001 and r = 0.626, P = .001, respectively). There was no significant difference between correlation coefficients (P = .836). CONCLUSION: Volumetric measurement of donor graft using 3-dimensional software provides comparable results to manual CT calculation of liver volume.

Diagnostic performances of intravoxel incoherent motion and conventional diffusion-weighted imaging in the differential diagnosis of benign and malignant portal vein thrombus.

PURPOSE: To evaluate the diagnostic accuracy of intravoxel incoherent motion (IVIM) and diffusion-weighted imaging (DWI) parameters in the differential diagnosis of portal vein thrombus (PVT). METHODOLOGY: Thirty-five patients with PVT were enrolled in this retrospective study. Precontrast axial in-phase and out-of-phase T1-weighted (W) turbo field echo (TFE), axial and coronal T2-W single-shot turbo spin echo, IVIM with b values between 0 and 1300 s/mm2 and conventional DWI with b factors of 50, 400, and 800 s/mm2 with single-shot echo-planar imaging, and postcontrast dynamic T1-W volumetric interpolated breath-hold examination images obtained with 1.5 T MR unit were evaluated. For quantitative analysis of conventional DWI, an ADC map was reconstructed from conventional DWI using all b values. For quantitative evaluation of IVIM, the SI was calculated from each b value. A specific software program was applied to calculate D (true diffusion coefficient), D* (pseudodiffusion coefficient associated with blood flow), and f (perfusion fraction). The differentiation between benign and malignant PVT was based on the criteria outlined in the study by Catalano et al. (Radiology 254:154-162, 2010). RESULTS: The ADC values of the malignant PVT were significantly lower than those of benign PVTs (p = 0.005). Malignant PVTs had a tendency to show higher f values in comparison with benign PVTs without statistical significance (p = 0.750). The best discriminative parameter was ADC values, which demonstrated a sensitivity of 80.0% and a specificity of 72.7% with cut-off value of 1.00 × 10-3 mm2/s. CONCLUSION: ADC values might be more superior tool than IVIM parameters in differentiation between malignant and benign PVT.

Liver Apparent Diffusion Coefficient Changes during Telaprevir-Based Therapy for Chronic Hepatitis C.

BACKGROUND: Diffusion-weighted imaging (DWI) has become an established diagnostic modality for the evaluation of liver parenchymal changes in diseases such as diffuse liver fibrosis. AIMS: To evaluate the parenchymal apparent diffusion coefficient value (ADC) changes using diffusion-weighted imaging (DWI) during telaprevir-based triple therapy. STUDY DESIGN: Diagnostic accuracy study. METHODS: Seventeen patients with chronic hepatitis C virus (HCV) virus and twenty-five normal volunteers were included. All of the patients took 12-weeks of telaprevir-based triple therapy followed by 12-weeks of PEGylated interferon and ribavirin therapy. They were examined before treatment (BT), as well as 12-weeks (W12) and 24-weeks (W24) after treatment by 3 Tesla magnetic resonance imaging (MRI). DWI was obtained using a breath-hold single-shot echo-planar spin echo sequence. Histopathologically, liver fibrosis was classified in accordance with the modified Knodell score described by Ishak. Quantitatively, liver ADCs were compared between patients and normal volunteers to detect the contribution of DWI in the detection of fibrosis. In addition, liver ADCs were compared during the therapy to analyze the effect of antiviral medication on liver parenchyma. RESULTS: The liver ADC values of fibrotic liver parenchyma were significantly lower than those of the healthy liver parenchyma (p<0.001). However, we were not able to reach a sufficiently discriminative threshold value. The ADC values showed a declining trend with increasing fibrotic stage. No statistically significant correlation (p=0.204) was observed. Compared with those before treatment, the liver ADC values after telaprevir-based triple therapy were significantly decreased at W12. A significant increase in the liver ADC values was also observed after the cessation of telaprevir therapy at W24 with a return to initial values. CONCLUSION: Liver ADC values appear to indicate the present but not the stage of liver fibrosis. DWI may be a helpful research tool for the assessment of antiviral drug effects.

Surgical experience in a baby with congenital broncho-biliary fistula.

Congenital tracheobiliary and bronchobiliary fistulae are rare malformations in which patent communications exist between the respiratory system and biliary tract, respectively. We present a newborn who was admitted with respiratory distress and bilious tracheal discharge. Investigation revealed a bronchobiliary fistula originating from the left main bronchus, as well as biliary atresia. Excision of the bronchobiliary fistula was successful and the connection between biliary tract and gastrointestinal system was established by performance of a Roux-en-Y cholecysto-jejunostomy. Diagnostic tools, differential diagnosis, and surgical correction strategies are discussed.