[Evaluation of the Validity of ROI Setting in CEI Used for the Assessment of Liver].

PURPOSE: The enhancement effect ratio using ethoxybenzyl (EOB) contrast is useful in the assessment of liver fibrosis. Since the enhancement effect ratio is calculated by setting a region of interest (ROI) in the liver, the ROI setting method may affect the enhancement effect ratio. One of the methods of setting the ROI in liver fibrosis evaluation is by placing the ROI in each Quinault segment, but this method requires considerable time. Therefore, it is necessary to consider a reproducible ROI setting method in contrast to the method of placing ROIs in each Quinault segment. METHOD: In contrast to the method of placing one ROI in each Quinault segment, we examined the method of setting four ROIs (two in the right lobe and two in the left lobe) and two ROIs (one in the right lobe and one in the left lobe). The size of the ROI was set to 1 cm2, 4 cm2, and the maximum area that fits within each placement area. CONCLUSION: In the ROI setting method for CEI calculation, reproducibility can be maintained by setting the number of ROIs in four locations and by setting ROIs of 4 cm2 or more.

Cloning of the dog bile salt export pump (BSEP; ABCB11) and functional comparison with the human and rat proteins.

The dog bile salt export pump (BSEP; ABCB11) was cloned and expressed in a Sf9 insect cell system. The deduced amino acid sequence encodes a 1325-amino-acid protein, which shows 89.4% and 80.2% homology with human BSEP and rat Bsep, respectively. The transcript of the dog Bsep gene was detected at a high level in liver, but not other tissues, by quantitative RT-PCR. The BSEP-expressing membrane vesicles isolated from Sf9 cells exhibited saturable uptake of [(3)H]taurocholic acid with Michaelis constants (K(m)) of 33.7, 22.2 and 19.9 microM for the dog, rat and human transporters, respectively. The uptake of [(3)H]taurocholic acid by all three transporters was significantly inhibited by troglitazone, glibenclamide, and other several inhibitors, while pravastatin inhibited dog Bsep and human BSEP, but not rat Bsep at 100 microM. The IC(50) of troglitazone for dog Bsep, human BSEP, and rat Bsep were 32, 20, and 60 microM, and those of pravastatin were 441, 240 and >1,000 microM, respectively. In conclusion, while dog Bsep shows similar ATP-dependent bile acid transport characteristics to human BSEP and rat Bsep, there is a species difference in affinity for drugs such as pravastatin and troglitazone.

Insomnia in patients on hemodialysis for a short versus long duration.

BACKGROUND: Many studies have investigated insomnia and the factors associated with this condition in hemodialysis (HD) patients, although the influence of HD duration has not been thoroughly investigated. In the present study, we investigated the factors, especially the duration of HD, associated with insomnia in HD patients. PATIENTS AND METHODS: A total of 138 patients undergoing HD were recruited, and the Japanese version of the Pittsburgh Sleep Quality Index (PSQI) was used to assess the quality of sleep. Subjects with a total PSQI score up to 4 and those with a score of at least 5 were identified as normal subjects and subjects with insomnia, respectively. Additionally, we assessed restless legs syndrome, depression using the Center for Epidemiologic Studies Depression Scale, and health-related quality of life (QOL) using the Short Form 8 Health Survey. We divided the subjects into two groups according to the median HD duration. RESULTS: The prevalence rate of insomnia was 54.3% among all the subjects. Twenty-one subjects (15.2%) had depression, 26 (18.8%) had restless legs syndrome, and 75 (54.3%) had insomnia. The median HD duration was 4 years. The scores of components 1 and 4 of the PSQI, subjective sleep quality and habitual sleep efficiency, did not show a significant difference between the normal and insomnia groups. The score of component 7, daytime dysfunction, showed a significant difference between the short and long HD duration groups. In multiple regression analysis, the score of the Short Form 8 Health Survey showed a significant association with the PSQI score in the long HD duration group, but no variable showed a significant association in the short HD duration group. CONCLUSION: Patients with a longer duration of HD indicated that insomnia has an influence on their daily activities, with a significant association between insomnia and QOL. Greater attention should be paid to poor QOL and troubles in daily activities caused by insomnia in patients with a longer HD duration.

Early detection of global cerebral anoxia: improved accuracy by high-b-value diffusion-weighted imaging with long echo time.

BACKGROUND AND PURPOSE: Early and accurate detection of global cerebral anoxia is important for determination of prognosis and further management. We evaluated whether accuracy in early detection of global cerebral anoxia was improved by high-b-value diffusion-weighted imaging (DWI) with long echo time (TE). METHODS: Routine DWI (b = 1000 s/mm(2); TE = 139 ms), high-b-value DWI (b = 3000 s/mm(2); TE = 190 ms), T2-weighted imaging (T2WI), and fluid-attenuated inversion recovery (FLAIR) imaging were acquired in six patients who experienced cardiopulmonary arrest within 24 hours and six volunteers. Region of interest-based analysis was performed. Regions of interest of patients showing significant decrease in apparent diffusion coefficient (ADC) values than volunteers were considered abnormal. Three neuroradiologists independently assessed images of the patients for conspicuity of hyperintensity within regions of interest. Receiver operating characteristic (ROC) analysis was performed, and the area under the curve (Az) was compared among sequences and observers. Average contrast and contrast-to-noise ratios between abnormal regions of interest and regions of interest of normal surrounding parenchyma were calculated. RESULTS: For all observers, high-b-value DWIs achieved the largest Az, and FLAIR imaging the lowest Az. Az of routine DWI and T2WI were between these values. High-b-value DWI and FLAIR imaging showed no significant interobserver variation in Az, whereas routine DWI and T2WI did. High-b-value DWI also achieved the largest contrast and contrast-to-noise ratios. CONCLUSION: High-b-value DWI with long TE improved accuracy in early detection of global cerebral anoxia. Application of the sequence would facilitate early diagnosis.

Percutaneous sacroplasty for hemorrhagic metastases from hepatocellular carcinoma.

Percutaneous injection of bone cement is a promising treatment for metastatic tumors. We present a case of hemorrhagic sacral metastases from hepatocellular carcinoma treated successfully by percutaneous sacroplasty with combined injections of bone cement and n-butyl cyanoacrylate resulting in pain relief.

Intravertebral cleft sign on fat-suppressed contrast-enhanced MR: correlation with cement distribution pattern on percutaneous vertebroplasty.

RATIONALE AND OBJECTIVES: Filling intravertebral clefts during percutaneous vertebroplasty (PVP) is considered to be important for optimal pain control. It is often difficult to detect clefts on non-contrast MR and some fractures show a solid pattern distribution of injected cement without a cleft sign on non-contrast MR. In this study, we evaluated usefulness of fat-suppressed contrast-enhanced MR to predict a solid pattern distribution of injected cement on PVP. MATERIALS AND METHODS: Twenty-six patients with 35 vertebral compression fractures due to osteoporosis were studied. We performed sagittal T1-weighted, T2-weighted and fat-suppressed contrast-enhanced T1-weighted images prior to PVP. First we evaluated the presence of fluid-filled or gas-containing clefts on non-contrast MR. Next we evaluated contrast-enhanced MR of the same vertebrae for the presence of cleft-shaped unenhanced areas within the diffuse enhancement area. We correlated MR findings with cement distribution patterns of injected cement. RESULTS: Based on MR findings, 35 osteoporotic fractures were divided into 3 types. Type 1 (11 fractures, 31%): There were no clefts on non-contrast MR and no unenhanced areas on contrast-enhanced MR; Type 2 (13, 37%): There were no clefts on non-contrast MR but there were unenhanced areas on contrast-enhanced MR; Type 3 (13, 37%): There were clefts on non-contrast MR and unenhanced areas on contrast-enhanced MR. Of 35 osteoporotic fractures, thirteen vertebral fractures (37%) were noted to contain clefts on non-contrast MR, while 24 vertebral fractures (69%) contained unenhanced areas on contrast-enhanced MR. Cement distributed as a solid pattern within clefts or unenhanced areas in all fractures with them. CONCLUSION: Fat-suppressed contrast-enhanced MR is useful to predict a solid pattern distribution of injected cement prior to PVP.

Anterior spinal artery and artery of Adamkiewicz detected by using multi-detector row CT.

BACKGROUND AND PURPOSE: Our purpose was to evaluate the visualization of the artery of Adamkiewicz (AKA) and the anterior spinal artery (ASA) by using multi-detector row CT. Preoperative detection of the AKA and ASA is important for prevention of ischemic complications of thoracoabdominal aortic surgery. METHODS: Data from contrast-enhanced CT of the abdomen of 19 consecutive patients with known or suspected liver disease were evaluated. The scanning range was set from the level of the diaphragm to the lower edge of the liver. After bolus injection of contrast material (100 mL of iohexol, 350 mgI/mL, 5 mL/s), arterial phase scans were obtained by using a four-channel multi-detector row CT scanner. The scanning parameters included a detector row configuration of 4 x 2 mm, a pitch of 5:1, a gantry rotation speed of 0.5 s, 120 kVp, and 150 mAs. Arterial phase coronal multiplanar reconstruction scans obtained parallel to the spinal cord were evaluated by two neuroradiologists. The detectability of ASA and AKA was analyzed. RESULTS: The AKA was visualized on the scans of 13 of 19 patients (68%). The segmental level of AKA origin ranged from T10 to L2. The AKA originated from the left side in nine patients (69%) and the right side in four patients (31%). The ASA was visualized on the scans of all patients (100%). For 16 of the 19 patients, the ASA was detected in its full length from the cranial edge of the scan range. However, the ascending branch of the ASA distal to the junction of the AKA was not detected for the remaining three patients. CONCLUSION: The AKA and ASA can be visualized by using multi-detector row CT with the use of IV administered contrast material. Multi-detector row CT could be a useful tool in the evaluation of spinal vascular structures.

Quantitative cerebral blood flow measurement with dynamic perfusion CT using the vascular-pixel elimination method: comparison with H2(15)O positron emission tomography.

BACKGROUND AND PURPOSE: Blood vessels are usually conspicuous on dynamic CT perfusion images. The presence of large vessels may lead to overestimation of the quantitative value of cerebral blood flow (CBF). We evaluated the efficacy of the vascular-pixel elimination (VPE) method in quantitative CT perfusion imaging, in comparison with positron emission tomography (PET). METHODS: Five healthy volunteers underwent CT perfusion and PET studies. A four-channel multi-detector row CT scanner was used. Dynamic cine scanning was performed after bolus injection of an intravenous contrast agent. CT-CBF was calculated by the central volume principle and deconvolution method. PET was performed after infusion of (15)O-labeled water. PET-CBF was calculated by using a nonlinear least squares method. Average CBF values of the whole section, gray matter, and white matter with both CT and PET were compared after image registration. The comparison was performed with and without VPE. In the VPE method, the vascular pixels were defined by the cerebral blood volume value of the pixel. The threshold of VPE was changed from 5 to 20 mL/100 g. Pixel-by-pixel correlation between CT-CBF and PET-CBF and linear regression analysis were also performed. RESULTS: Without VPE, CT-CBF was overestimated in all subjects. As the VPE threshold decreased, CT-CBF decreased and the correlation coefficient increased. The best correlation was observed at a VPE threshold of 8 mL/100 g in four of the five subjects. Average CT-CBF values, without VPE, of the whole section, gray matter, and white matter were 59.01, 66.73, and 42.53 mL/100 g/min, respectively. With VPE (threshold, 8 mL/100 g), average CT-CBF values of the whole section, gray matter, and white matter were 45.56, 52.75, and 30.38, respectively. The corresponding PET-CBF values were 46.86, 50.89, and 38.20 mL/100 g/min, respectively. CONCLUSION: Vascular pixels should be excluded from the calculation of CT-CBF to avoid overestimation of the CBF values. If vascular pixels are excluded, CBF calculation with CT perfusion imaging is considerably accurate.

Differences in UGT1A1, UGT1A7, and UGT1A9 polymorphisms between Uzbek and Japanese populations.

BACKGROUND AND OBJECTIVES: Uridine-diphosphate glucuronosyltransferase 1A (UGT1A) is a key enzyme involved in irinotecan metabolism, and polymorphisms in the UGT1A gene are associated with irinotecan-induced toxicity. The aim of this study was to elucidate the allele frequencies of UGT1A polymorphisms in healthy Uzbek volunteers, and to compare them with those of the Japanese population. METHOD: A total of 97 healthy volunteers from Uzbekistan were enrolled and blood samples were collected from each participant. Genotyping analysis was performed by fragment size analysis for UGT1A1*28, direct sequencing for UGT1A7*3 and UGT1A9*22, and TaqMan assays for UGT1A1*93, UGT1A1*6, UGT1A1*27, UGT1A1*60, and UGT1A7*12. The frequencies of polymorphisms were compared with the Japanese population by using the data previously reported from our study group. RESULTS: When the Uzbek and Japanese populations were compared, heterozygotes or homozygotes for UGT1A1*28, UGT1A1*60, and UGT1A1*93 were significantly more frequent in the Uzbek population (P < 0.01). The rate of UGT1A7*12 was not significantly different between the two populations, whereas UGT1A1*6 and UGT1A9*22 were significantly less frequent in the Uzbek population (P < 0.05). UGT1A7*1 were less prevalent in the Uzbek population than in the Japanese population (P < 0.01). CONCLUSION: The Uzbek population has different frequencies of polymorphisms in UGT1A genes compared with the Japanese population. A comprehensive study of the influence of UGT1A1 polymorphisms on the risk of irinotecan-induced toxicity is necessary for optimal use of irinotecan treatment.

Diffusion tensor MR imaging of the cervical spinal cord in patients with multiple sclerosis.

Our purpose was to evaluate the ability of diffusion tensor imaging (DTI) to characterize cervical spinal cord white matter (WM) in patients with multiple sclerosis (MS). DTI were obtained in 21 MS patients and 21 control subjects (CS). Regions of interest (ROIs) were placed at C2/3, C3/4, and C4/5 within the right, left, and dorsal (WM) to calculate fractional anisotropy (FA) and the apparent diffusion coefficient (ADC). Measurements in plaques and normal-appearing white matter (NAWM) of MS patients were compared with mean FA and ADC of WM in CS. FA was significantly lower in all regions in MS patients than in CS. ADC was significantly higher in all regions in MS patients than in CS except for in the dorsal WM at C2/3 and the bilateral WM at C4/5. The mean FA was 0.441 for plaques and 0.542 for NAWM, as compared with 0.739 in CS. The mean ADC was 0.810 x 10(-3) mm(2)/s for plaques and 0.722 x 10(-3) mm(2)/s for NAWM, as compared with 0.640 x 10(-3) mm(2)/s for CS. FA and ADC showed significant differences between plaques, NAWM and control WM(P < 0.01).