Benefits and problems of transarterial therapy in patients with hepatocellular carcinoma and chronic kidney disease.

PURPOSE: To evaluate the feasibility of transarterial therapy (transcatheter arterial chemoembolization and transcatheter arterial infusion) for patients with hepatocellular carcinoma and chronic kidney disease (CKD). MATERIALS AND METHODS: The study enrolled 35 patients who received transarterial therapy. The patients were classified into a CKD group (n = 10 nondialysis chronic kidney disease [NDCKD] and n = 9 end-stage renal disease [ESRD]) or a non-CKD group (n = 16). The survival rates between the two groups were compared using two different starting points: (a) from initial diagnosis of hepatocellular carcinoma and (b) from enrollment in the study. The tolerance of transarterial therapy in patients with CKD was evaluated by comparing the incidence of major adverse events. RESULTS: The 2-year and 5-year survival rates from initial diagnosis were 83.9% and 53.8% in the CKD group and 70.1% and 40.4% in the non-CKD group (P = .478). The corresponding 3-year survival rate from enrollment in the two groups was 25.6% and 41.2%, respectively (P = .995). The 2-year and 5-year survival rates from initial diagnosis were 70.1% and 40.4% in the non-CKD group, 90.0% and 39.4% in NDCKD patients, and 76.2% and 76.2% in ESRD patients (P = .380). The corresponding 2-year survival rates from enrollment in these groups were 54.9%, 48.0%, and 48.6% (P = .943). Severe contrast-induced nephropathy (n = 3) and late-onset death caused by cholesterol crystal embolism (n = 1) were observed in the NDCKD group. CONCLUSIONS: Transcatheter arterial chemoembolization is feasible in patients with CKD by instituting periprocedural hemodialysis with similar 2-year and 5-year survival compared with patients without CKD.

A scoring system based on computed tomography for the correct diagnosis of xanthogranulomatous cholecystitis.

BACKGROUND: Xanthogranulomatous cholecystitis (XGC) is an uncommon variant of chronic cholecystitis. The differential diagnoses of XGC include gallbladder cancer (GBC), adenomyomatosis, and actinomycosis of the gallbladder. PURPOSE: To assess the usefulness of computed tomography (CT) findings in the diagnosis of XGC and differentiation from GBC. MATERIAL AND METHODS: We retrospectively assessed the pathological and radiological records of 13 patients with pathologically proven XGC and 33 patients with GBC. RESULTS: Significant differences were observed for the following five CT findings: diffuse wall thickening (XGC = 85%, GBC = 15%, P < 0.01); absence of polypoid lesions (XGC = 100%, GBC = 48%, P < 0.01); intramural nodules or bands (XGC = 54%, GBC = 9%, P < 0.01); pericholecystic infiltration (XGC = 69%, GBC = 9%, P < 0.01); and pericholecystic abscess (XGC = 23%, GBC = 0%, P = 0.018). We defined the scoring system based on how many of the five CT findings were observed. Our scoring system, which included these findings, revealed that patients with three or more findings had sensitivity of 77% (95% confidence interval [CI] = 57-87) and specificity of 94% (95% CI = 86-98). CONCLUSION: Our scoring system can assist in the differentiation of XGC from GBC.

Image Non-Uniformity Correction for 3-T Gd-EOB-DTPA-Enhanced MR Imaging of the Liver.

PURPOSE: Image non-uniformity may cause substantial problems in magnetic resonance (MR) imaging especially when a 3-T scanner is used. We evaluated the effect of image non-uniformity correction in gadolinium ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced MR imaging using a 3-T scanner. METHODS: Two commercially available methods for image non-uniformity correction, surface coil intensity correction (SCIC), and phased-array uniformity enhancement (PURE), were applied to Gd-EOB-DTPA-enhanced images acquired at 3-T in 20 patients. The calibration images were used for PURE and not for SCIC. Uniformity in the liver signal was evaluated visually and using histogram analysis. The liver-to-muscle signal ratio (LMR) and liver-to-spleen signal ratio (LSR) were estimated, and the contrast enhancement ratio (CER) was calculated from the liver signal, LMR, and LSR. RESULTS: Without non-uniformity correction, hyperintensity was consistently observed near the liver surface. Both SCIC and PURE improved uniformity in the liver signal; however, the superficial hyperintensity remained after the application of SCIC, especially in the hepatobiliary-phase images, and focal hyperintensity was shown in the lateral segment of the left hepatic lobe after the application of PURE. PURE increased LMR dramatically and LSR mildly, with no changes in CERs. SCIC depressed temporal changes in LMR and LSR and obscured contrast effects, regardless of the method used for calculation of CER. CONCLUSION: SCIC improves uniformity in the liver signal; however, it is not suitable for a quantitative assessment of contrast effects. PURE is indicated to be a useful method for non-uniformity correction in Gd-EOB-DTPA-enhanced MR imaging using a 3-T scanner.

Evaluation of a respiratory navigator-gating technique in Gd-EOB-DTPA-enhanced magnetic resonance imaging for the assessment of liver tumors.

OBJECTIVES: We investigated the clinical usefulness of respiratory navigator-gating technique for the assessment of liver tumors in Gd-EOB-DTPA-enhanced magnetic resonance (MR) imaging. METHODS: Eighty patients who underwent Gd-EOB-DTPA-enhanced MR imaging to evaluate known or suspected liver tumors were enrolled. Three-dimensional spoiled gradient-recalled echo images of the liver were acquired in the hepatobiliary phase by the following three methods: breath-hold imaging, navigator-gated low-resolution imaging, and navigator-gated high-resolution imaging. Navigator-gated imaging was performed during free breathing. Spatial resolution was identical between breath-hold imaging and gated low-resolution imaging. Signal intensities in the liver, muscle, and spleen were measured in 20 patients. Image quality was visually evaluated in all 80 patients. The detection rate and lesion conspicuity were assessed for 71 malignant liver lesions identified in 29 patients. RESULTS: The liver-to-muscle and liver-to-spleen signal ratios were significantly lower for gated images compared to breath-hold images. Images of acceptable quality were obtained in most patients by all three methods, and the overall image quality of axial images did not differ significantly among the imaging methods, although superior reformatted coronal images were obtained by gated high-resolution imaging. The detection rates of malignant liver lesions were similar among the three imaging methods, although lesion conspicuity was significantly better for breath-hold imaging compared to gated imaging. CONCLUSIONS: Navigator-gated imaging provided image qualities and detection rates of malignant liver lesions comparable to breath-hold imaging in Gd-EOB-DTPA-enhanced MR imaging; however, no additional benefits of high-resolution imaging were proven for lesion evaluation.

Optimal techniques for magnetic resonance imaging of the liver using a respiratory navigator-gated three-dimensional spoiled gradient-recalled echo sequence.

PURPOSE: To optimize the navigator-gating technique for the acquisition of high-quality three-dimensional spoiled gradient-recalled echo (3D SPGR) images of the liver during free breathing. MATERIALS AND METHODS: Ten healthy volunteers underwent 3D SPGR magnetic resonance imaging of the liver using a conventional navigator-gated 3D SPGR (cNAV-3D-SPGR) sequence or an enhanced navigator-gated 3D SPGR (eNAV-3D-SPGR) sequence. No exogenous contrast agent was used. A 20-ms wait period was inserted between the 3D SPGR acquisition component and navigator component of the eNAV-3D-SPGR sequence to allow T1 recovery. Visual evaluation and calculation of the signal-to-noise ratio were performed to compare image quality between the imaging techniques. RESULT: The eNAV-3D-SPGR sequence provided better noise properties than the cNAV-3D-SPGR sequence visually and quantitatively. Navigator gating with an acceptance window of 2mm effectively inhibited respiratory motion artifacts. The widening of the window to 6mm shortened the acquisition time but increased motion artifacts, resulting in degradation of overall image quality. Neither slice tracking nor incorporation of short breath holding successfully compensated for the widening of the window. CONCLUSION: The eNAV-3D-SPGR sequence with an acceptance window of 2mm provides high-quality 3D SPGR images of the liver.

Usefulness of the navigator-echo triggering technique for free-breathing three-dimensional magnetic resonance cholangiopancreatography.

PURPOSE: To prospectively compare the navigator-echo triggering technique (navigator technique) and the conventional respiratory triggering technique using bellows (bellows technique) for free-breathing three-dimensional (3D) magnetic resonance cholangiopancreatography (MRCP) under clinical conditions. MATERIALS AND METHODS: Forty patients referred for evaluation of biliary or pancreatic diseases underwent 3D MRCP examination using both navigator and bellows techniques. Two independent radiologists visually evaluated the image quality of 12 segments of the pancreaticobiliary tree in a blinded manner. In addition, the clarity of the lesion was compared between the two techniques in a side-by-side manner. RESULT: MRCP images were successfully acquired using both techniques in all patients. No significant difference in acquisition time was found between the two techniques. The image quality was significantly better using the navigator technique than using the bellows technique for the following seven segments: the head, body, and tail of the pancreatic duct; right hepatic duct; anterior and posterior segments of the right hepatic duct; and cystic duct. The other segments (common hepatic and bile duct, left hepatic duct, medial and lateral segments of left hepatic duct, gallbladder) showed no significant difference. The clarity of lesion depiction was significantly better using the navigator technique than using the bellows technique. CONCLUSION: Respiratory-triggered 3D MRCP using the navigator technique was shown to be feasible in routine clinical practice. The navigator technique improved the image quality of free-breathing 3D MRCP compared with the bellows technique. The clarity of lesion visualization was also better using the navigator technique than using the bellows technique.

Improved reproducibility of simple quantitative indices from 99mTc-GSA liver functional imaging.

OBJECTIVE: We evaluated intra- and interoperator reproducibilities in calculating the conventional indices HH15 and LHL15 from (99m)Tc-diethylenetriamine pentaacetic acid galactosyl human serum albumin ((99m)Tc-GSA) scintigraphy, and proposed new, simple methods for the calculation of quantitative indices. METHODS: The results of (99m)Tc-GSA scintigraphy in 33 patients were retrospectively analyzed. Heart and liver ROIs were drawn manually to cover cardiac blood pool and entire liver, respectively, and HH15 and LHL15 were calculated. In addition, square regions of interest (ROIs) of fixed sizes were placed at the highest activity in blood pool and the liver. Using the square heart ROI, sHH15, an equivalent of HH15, was computed. Fractional liver uptake at 15 min (FLU15) was calculated using the square heart and liver ROIs. Intra- and interoperator reproducibilities, as well as correlation with Indocyanine green retention rate at 15 min (ICG R15), were assessed for these four indices by linear regression analysis. RESULTS: Substantial intra- and interoperator variabilities were found for HH15 and LHL15. The correlation coefficients for intra- and interoperator comparisons were 0.884 and 0.869 for HH15, respectively, and 0.919 and 0.917 for LHL15, respectively. The use of square ROIs instead of hand-drawn ROIs improved reproducibility. The correlation coefficients for intra- and interoperator comparisons were 0.988 and 0.973 for sHH15, respectively, and 0.989 and 0.975 for FLU15, respectively. Correlation with ICG R15 was better for sHH15 (r = 0.619) and FLU15 (r = -0.656) than for HH15 (r = 0.439) and LHL15 (r = -0.490). CONCLUSIONS: HH15 and LHL15 showed substantial intra- and interoperator variabilities, and the use of square ROIs are indicated to provide better reproducibility.