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Background: There are limited numbers of PET studies of solid pseudopapillary tumors (SPT) of the pancreas., Materials and Methods: We reviewed the medical records of 37 patients who underwent resection of pancreatic SPT and had been preoperatively evaluated by (18)F-FDG PET or PET/CT scan. Immunohistochemical analysis of glucose transporter-1 (GLUT-1) and hexokinase II (HK-II) was performed., Results: SPT could be categorized into five types according to the morphologic characteristics observed in PET images. Type I (hot FDG uptake in the entire tumor portion) was the most frequent (13, 34.2%), followed by type IV (focal uptake, 12, 31.6%), II (focal defect, 8, 21.1%), III (multiple and geographic uptake, 3, 7.9%), and V (total defective type, 1, 2.6%). The SUVmax in the solid portion of the SPT was 5.3 ± 4.1. The clinical pattern of FDG uptake in SPT was not associated with histopathologic features suggesting malignant potential. The SUVmax of SPT followed a pattern according to pattern of FDG uptake (R(2) = 0.203, p = 0.055), and was significantly associated with adjusted tumor volume (p = 0.001). GLUT-1 was not expressed in SPT, and only eight patients (12.3%) showed mild to moderate expression of HK-II, which was associated with the clinical pattern of SPT in PET images (p < 0.05)., Conclusion: SPT of the pancreas could be categorized according to the morphologic patterns observed in PET images. The clinical significance of FDG uptake, glucose metabolism, and clinical usefulness of PET scan in SPT need to be further investigated, and thus this tumor remains a surgical enigma., (Copyright © 2014 IAP and EPC. Published by Elsevier B.V. All rights reserved.)

Purpose/aim of the Study: To assess the feasibility of krypton-enhanced ventilation CT using dual energy (DE) technique for various krypton concentrations and to determine the appropriate krypton concentration for DE ventilation CT through an animal study., Materials and Methods: Baseline DECT was first performed on seven New Zealand white rabbits. The animals were then ventilated using 20%, 30%, 40%, 50%, 60%, to 70% krypton concentration, and DECT was performed for each concentration. Krypton extraction was performed through a workstation, and results were displayed on a color map. Overlay Hounsfield unit (HU) values were obtained by two observers in consensus readings. A linear mixed model was used to correlate overlay HU values and krypton concentrations. Visual assessments of the homogeneity of krypton maps were also performed., Results: Mean overlay HU values according to krypton concentration were as follows; 20% krypton, 1.68 ± 5.15; 30% krypton, 3.73 ± 5.93; 40% krypton, 6.92 ± 5.51; 50% krypton, 10.88 ± 5.17; 60% krypton, 14.54 ± 4.23; and 70% krypton, 18.79 ± 3.63. We observed a significant correlation between overlay HU values on krypton maps and krypton concentrations (P < .001). For the krypton color maps, all observers determined universal enhancement on the 70% krypton map for all animals., Conclusion: It is feasible to evaluate lung ventilation function using DECT with a krypton concentration of at least 70%.

Objective: The objective of our study was to determine the feasibility of using Metal Artifact Reduction (MAR) software for abdominopelvic dual-energy CT in patients with metal hip prostheses., Materials and Methods: This retrospective study included 33 patients (male-female ratio, 19:14; mean age, 63.7 years) who received total hip replacements and 20 patients who did not have metal prostheses as the control group. All of the patients underwent dual-energy CT. The quality of the images reconstructed using the MAR algorithm and of those reconstructed using the standard reconstruction was evaluated in terms of the visibility of the bladder wall, pelvic sidewall, rectal shelf, and bone-prosthesis interface and the overall diagnostic image quality with a 4-point scale. The mean and SD attenuation values in Hounsfield units were measured in the bladder, pelvic sidewall, and rectal shelf. For validation of the MAR interpolation algorithm, pelvis phantoms with small bladder "lesions" and metal hip prostheses were made, and images of the phantoms both with and without MAR reconstruction were evaluated., Results: Image quality was significantly better with MAR reconstruction than without at all sites except the rectal shelf, where the image quality either had not changed or had worsened after MAR reconstruction. The mean attenuation value was changed after MAR reconstruction to its original expected value at the pelvic sidewall (p < 0.001) and inside the bladder (p < 0.001). The SD attenuation value was significantly decreased after MAR reconstruction at the pelvic sidewall (p = 0.019) but did not show significant differences at the bladder (p = 0.173) or rectal shelf (p = 0.478). In the phantom study, all lesions obscured by metal artifacts on the standard reconstruction images were visualized after MAR reconstruction; however, new artifacts had developed in other parts of the MAR reconstruction images., Conclusion: The use of MAR software with dual-energy CT decreases metal artifacts and increases diagnostic confidence in the assessment of the pelvic cavity but also introduces new artifacts that can obscure pelvic structures.

Objectives: To assess the value of a CT-based abdominal aortic calcification (AAC) score as a surrogate marker for the presence of asymptomatic coronary artery disease (CAD)., Methods: The AAC scores of 373 patients without cardiac symptoms who underwent both screening coronary CT angiography and abdominal CT within one year were calculated according to the Agatston method. Logistic regression was used to derive two multivariate models from traditional cardiovascular risk factors, with and without AAC scores, to predict the presence of CAD. The AAC score and the two multivariate models were compared by calculating the area under the receiver operating characteristic curve (AUC) and the net reclassification improvement (NRI)., Results: The AAC score alone showed a marginally higher AUC (0.823 vs. 0.767, P = 0.061) and significantly better risk classification (NRI = 0.158, P = 0.048) than the multivariate model without AAC. The multivariate model using traditional factors and AAC did not show a significantly higher AUC (0.832 vs. 0.823, P = 0.616) or NRI (0.073, P = 0.13) than the AAC score alone. The optimal cutoff value of the AAC score for predicting CAD was 1025.8 (sensitivity, 79.5 %; specificity, 75.9 %)., Conclusions: AAC scores may serve as a surrogate marker for the presence or absence of asymptomatic CAD., Key Points: • Severe vascular calcification indicates a high probability of coronary artery disease. • Vascular calcification in the abdominal aorta can be quantified by computed tomography. • Abdominal CT could lead to early detection of asymptomatic coronary artery disease.

Objectives: The aims of this study were to analyze cumulative effective dose (cED) and to assess lifetime attributable risk (LAR) of cancer due to radiation exposure during computed tomography (CT) examinations in adolescent trauma patients., Methods: Between January 2010 and May 2011, the adolescent patients with trauma were enrolled in this study. Numbers of CT examinations and body regions examined were collated, and cEDs were calculated using dose-length product values and conversion factors. Lifetime attributable risk for cancer incidence and cancer-associated mortality were quantified based on the studies of survivors of the atomic bombs on Japan. Data were stratified according to severity of trauma: minor trauma, injury severity score of less than 16; and major trauma, injury severity score of 16 or greater., Results: A total of 698 CT scans were obtained on the following regions of 484 adolescent patients: head CT, n = 647; rest of the body, n = 41; and thorax, n = 10. Mean cED per patient was 3.4 mSv, and mean LARs for cancer incidence and mortality were 0.05% and 0.02%, respectively. The majority of patients (98.4%) experienced minor trauma, and their mean cED and LARs for cancer incidence and mortality (3.0 mSv and 0.04% and 0.02%, respectively) were significantly lower than those of patients with major trauma (24.3 mSv and 0.31% and 0.15%, respectively, all P values < 0.001)., Conclusions: The overall radiation-induced cancer risk due to CT examinations performed for the initial assessment of minor trauma was found to be relatively low in adolescent patients. However, adolescent patients with major trauma were exposed to a substantial amount of radiation during multiple CT examinations.

The causes of hemolysis, elevated liver enzymes, and low platelet count (HELLP) syndrome or hepatic hemorrhage as a serious complication of HELLP are not known. Although spontaneous hepatic rupture associated with HELLP syndrome is a rare complication of pregnancy, hepatic rupture results in life-threatening complications. The cornerstone of prognosis is early diagnosis. Hepatic rupture in HELLP syndrome should be considered a differential diagnosis in pregnant patients with sudden onset of abdominal pain or hypotension. We report a case of 30-year-old primigravida female with spontaneous hepatic rupture caused by HELLP syndrome as a presenting symptom of right upper quadrant abdominal pain.

Objectives: The purpose of this prospective study was to investigate the usefulness of acoustic radiation force impulse (ARFI) elastography of the pancreas for predicting postoperative pancreatic fistula occurrence after pancreatic resection., Methods: Twenty-five patients underwent ARFI elastography of the pancreas before pancreatic resection (11 men and 14 women; mean age, 59.1 years; range, 28-76 years). In each patient, 3 valid ARFI measurements (meters per second) were performed at the head of the pancreas, and the median values were calculated. Patients underwent pancreaticoduodenectomy (n = 18) or distal pancreatectomy (n = 7). Clinically relevant fistulas (grade B or higher) were determined according to the standard criteria used by the International Study Group on Pancreatic Fistula. Preoperative ARFI values were compared between the fistula and nonfistula groups (Mann-Whitney test)., Results: Clinically relevant fistulas (grade B or higher) were observed in 8 patients (32%; fistula group), including 5 of 18 patients with pancreaticoduodenectomy (28%) and 3 of 7 patients with distal pancreatectomy (43%). The ARFI values in the fistula group (median, 1.45 m/s; range, 0.80-1.98 m/s) were lower than in the nonfistula group (median, 1.54 m/s; range, 0.98-3.40 m/s), but there was no statistical significance (P = .1374). When confining the results to only patients with pancreaticoduodenectomy, the ARFI values were significantly lower in the patients with fistulas (median, 0.98 m/s; range, 0.80-1.94 m/s) than in those without fistulas (median, 1.60 m/s; range, 1.08-3.40 m/s; P = .0460)., Conclusions: This preliminary study showed the potential feasibility of a clinical application of ARFI elastography in preoperatively predicting postoperative pancreatic fistulas after pancreaticoduodenectomy. Investigation of this method in larger studies is needed.

Postoperative pancreatic fistula (POPF) combined with postoperative fluid collection, bleeding and abscess formation is one of the most critical morbidities after distal pancreatectomy or pancreaticoduodenectomy. Percutaneous catheter drainage has been commonly used for managing for the postoperative management of abnormal fluid collection. Removal of the catheter is rarely associated with occurrence of life-threatening complication such as serious liver damage. Herein, we report a case of unexpected fatal liver injury complicated by percutaneous catheter drainage treatment after distal pancreatosplenectomy in a patient with pancreatic cancer. We suggest that prudent decision for timing of catheter removal and meticulous care during procedure can reduce the possibility of major liver injury in patients with percutaneous transhepatic catheter drainage.

Objectives: The objectives of the study were to evaluate the image quality and diagnostic performance of sinogram-affirmed iterative reconstruction (SAFIRE) for detecting hepatic metastasis and to estimate the potential radiation dose reduction at abdominal computed tomography (CT)., Materials and Methods: Fifty-nine consecutive patients (mean age, 59.2 years; range, 42-81 years) who had hepatic metastasis and who underwent dual-source abdominal CT were enrolled in this study. The image noise of the liver was compared between full-dose filtered back projection images (FD-FBP) and simulated half-dose images, which used only single-source projection data, and reconstructed with different strengths of SAFIRE (HD-SAFIRE(1-5)) by 1-way analysis of variance with Bonferroni correction. The diagnostic performance for hepatic metastasis was compared by logistic regression with the weighted least squares method and noninferiority test between the FD-FBP images and the half-dose sinogram-affirmed iterative reconstruction (HD-SAFIRE) images., Results: As the SAFIRE strength increased, image noise decreased (P < 0.001). The images of HD-SAFIRE(2) showed similar image noise for liver parenchyma (13.4 Hounsfield unit [HU]), signal-to-noise ratio for liver parenchyma (9.2), and lesion-to-liver contrast-to-noise ratio (4.5), compared with the FD-FBP images (12.6 HU, P = 0.668; 9.6, P > 0.999; and 4.5, P > 0.999, respectively). The diagnostic accuracy for hepatic metastasis with the HD-SAFIRE(2) images (87.5%) was not different from that of the FD-FBP images (87.5%, P > 0.999). The diagnostic performance of the HD-SAFIRE(2) images was also noninferior to that of the FD-FBP images (95% confidence interval lower limit difference [-9.16%] excluding the -10% clinical noninferiority limit). The mean (SD) volume CT dose index of FD-FBP was 11.26 (2.66) mGy, and the mean (SD) radiation dose equivalent associated with HD-SAFIRE was estimated to be 5.63 (1.33) mGy., Conclusions: By applying SAFIRE2, the radiation dose could be reduced by up to 50% compared with the standard-of-care abdominal CT protocol without increasing image noise and without deteriorating diagnostic performance for the detection of hepatic metastasis.

Purpose: We obtained intravoxel incoherent motion (IVIM) parameters through biexponential analysis on diffusion-weighted MR imaging (DWI) using multiple b values. Correlation was evaluated between these parameters and histological microvessel density (MVD) for the possibility of noninvasive evaluation of MVD with DWI., Methods: Twenty-five nude mice with the HT29 colorectal cancer cells implanted were analyzed after undergoing DWI with multiple b values (0, 50, 100, 300, 500, 700, and 1000 s/mm(2)). Tissue diffusivity (D(t)), pseudo-diffusion coefficient (D(p)), and perfusion fraction (f(p)) were calculated using a biexponential analysis, and these parameters were correlated with MVD. The MVD was determined with the CD31 stain. For statistical analysis, Spearman's rank correlation was applied., Results: The mean value and correlation coefficient with MVD for each IVIM parameter were as follows: D(t)  = 0.98 ± 0.06 × 10(-3) mm(2)/s with r = 0.139 (P = 0.508); D(p) = 23.70 ± 7.94 × 10(-3) mm(2)/s with r = 0.782 (P < 0.001); and f(p) = 15.58 ± 5.7% with r = 0.749 (P < 0.001). D(p) and f(p) showed significant correlation with MVD, but D(t) did not., Conclusion: The IVIM parameters, D(p) and f(p), on DWI might be used in the noninvasive evaluation of MVD., (Copyright © 2013 Wiley Periodicals, Inc.)

Objective: To compare the accuracy of multidetector computed tomography (MDCT) and gadoxetic acid-enhanced magnetic resonance imaging (MRI) for the detection of intrahepatic tumor recurrence after curative resection of hepatocellular carcinoma (HCC)., Materials and Methods: Fifty-six patients who underwent MDCT and gadoxetic acid-enhanced MRI for postoperative surveillance after resection of HCC were retrospectively analyzed; 26 patients had a recurrence (36 lesions) and 30 patients did not. Recurrent HCCs were confirmed by histological examinations in two, typical dynamic imaging findings on CT and/or MRI in 28, and by demonstration of growth or tumor staining on angiography on six. Two reviewers graded the confidence for the presence of recurrence on CT and MRI, using a five-point scale. The jackknife free-response receiver operating characteristic method was used to compare diagnostic performance. The accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated., Results: For 36 recurrent lesions, the figure of merit was significantly higher for MRI than MDCT for detecting recurrence for both reviewers (p < 0.005 for both reviewers). In lesion-by-lesion analysis, the sensitivity was significantly higher on MRI (100% for reviewer 1 and 97% for reviewer 2) than on MDCT (44.4% and 66.6%) for both reviewers (p < 0.005 for both reviewers). Also in patient-by-patient analysis, sensitivity was significantly higher on MRI (100% and 96.1%) than on MDCT (57.6% and 76.9%) for both reviewers (p < 0.05 for both reviewers)., Conclusion: Gadoxetic acid-enhanced MRI is superior to MDCT for detecting intrahepatic recurrence after curative resection of HCC.

Background: This study aimed to investigate the clinical relevance of splenic vein thrombosis (SVT) in the splenic vein remnant following minimally invasive distal pancreatosplenectomy (DPS)., Methods: Medical records of patients who underwent laparoscopic or robotic distal pancreatectomy (DP) with or without splenectomy between January 2006 and August 2012 were reviewed. Rates of SVT and clinically relevant postoperative pancreatic fistula (POPF) were compared in a group of patients undergoing DPS and a group having spleen-preserving DP., Results: Seventy-nine patients had minimally invasive DP, of whom 38 (48 per cent) developed SVT in the splenic vein remnant. DPS was associated with POPF (P = 0.001) and SVT (P < 0.001). SVT length was closely related to the amount of peripancreatic fluid collection (P = 0.025) and POPF (P = 0.045). In a comparison of splenic vessel-sacrificing, spleen-preserving DP and DPS, postoperative platelet count was significantly higher in the DPS group (P < 0.001). In addition, grade of SVT (P = 0.092) and POPF (P = 0.065) tended to be associated with DPS, suggesting that SVT may be related to both splenectomy and POPF., Conclusion: Minimally invasive DPS is associated with SVT and POPF. Preservation of the spleen should be considered when treating patients with benign and borderline malignant tumours of the distal pancreas., (© 2013 BJS Society Ltd. Published by John Wiley & Sons Ltd.)

In contrast to patients with underlying cancer or chronic disease, injury patients are relatively young, and can be expected to live their natural lifespan if injuries are appropriately treated. Multiple and repeated diagnostic scans might be performed in these patients during admission. Nevertheless, radiation exposure in injury patients has been overlooked and underestimated because of the emergent nature of such situations. Therefore, we tried to assess the cumulative effective dose (cED) of injury patients in the emergency department. We included patients who visited the emergency department (ED) of a single tertiary hospital due to injury between February 2010 and February 2011. The cED for each patient was calculated and compared across age, sex and injury mechanism. A total of 11,676 visits (mean age: 28.0 years, M:F = 6,677:4,999) were identified. Although CT consisted of only 7.8% of total radiologic examinations (n=78,025), it accounted for 87.1% of the total cED. The mean cED per visit was 2.6 mSv. A significant difference in the cED among injury mechanisms was seen (p<0.001) and patients with traffic accidents and fall down injuries showed relatively high cED values. Hence, to reduce the cED of injury patients, an age-, sex- and injury mechanism-specific dose reduction strategy should be considered.

Although lower vitamin D and higher parathyroid hormone (PTH) concentrations have been associated with hypertension, their independent contribution to blood pressure (BP) is unclear. The independent associations of serum 25-hydroxyvitamin D (25[OH]D) and PTH levels with BP were therefore investigated. This is a population-based cross-sectional study from the Korea National Health and Nutrition Examination Surveys, which includes a total of 4,513 participants (2,019 men and 2,494 women) aged ≥ 50 years. 25(OH)D and PTH were measured by radioimmunoassays, and BP was determined with a sphygmomanometer. Hypertensive subjects had significantly lower 25(OH)D (p = 0.023) and significantly higher PTH (p < 0.001) concentrations than normotensives. In subjects not taking antihypertensive medications, 25(OH)D showed reverse correlations with systolic and diastolic BP, both in men (p = 0.038-0.061 and p = 0.011-0.038, respectively) and in women (p = 0.006-0.018 and p = 0.001-0.011, respectively), while serum PTH concentrations showed positive correlations with systolic and diastolic BP in men (p = 0.001-0.014 and p < 0.001, respectively) and women (p < 0.001-0.008 and p = 0.001-0.040, respectively). When 25(OH)D and PTH were included in the same model, both remained independently associated with BP in men and women. In conclusion, both lower 25(OH)D and higher PTH may be independent factors for the development of hypertension.

Objective: To evaluate the feasibility of sinogram-affirmed iterative reconstruction (SAFIRE) and automated kV modulation (CARE kV) in reducing radiation dose without increasing image noise for abdominal CT examination., Materials and Methods: This retrospective study included 77 patients who received CT imaging with an application of CARE kV with or without SAFIRE and who had comparable previous CT images obtained without CARE kV or SAFIRE, using the standard dose (i.e., reference mAs of 240) on an identical CT scanner and reconstructed with filtered back projection (FBP) within 1 year. Patients were divided into two groups: group A (33 patients, CT scanned with CARE kV); and group B (44 patients, scanned after reducing the reference mAs from 240 to 170 and applying both CARE kV and SAFIRE). CT number, image noise for four organs and radiation dose were compared among the two groups., Results: Image noise increased after CARE kV application (p < 0.001) and significantly decreased as SAFIRE strength increased (p < 0.001). Image noise with reduced-mAs scan (170 mAs) in group B became similar to that of standard-dose FBP images after applying CARE kV and SAFIRE strengths of 3 or 4 when measured in the aorta, liver or muscle (p ≥ 0.108). Effective doses decreased by 19.4% and 41.3% for groups A and B, respectively (all, p < 0.001) after application of CARE kV with or without SAFIRE., Conclusion: Combining CARE kV, reduction of mAs from 240 to 170 mAs and noise reduction by applying SAFIRE strength 3 or 4 reduced the radiation dose by 41.3% without increasing image noise compared with the standard-dose FBP images.

Objective: The purpose of this study was to describe the enhancement patterns of mass-forming intrahepatic cholangiocarcinomas on gadoxetate disodium-enhanced MR images using imaging-histologic correlation., Materials and Methods: We retrospectively evaluated the preoperative gadoxetate disodium-enhanced MR images of 19 patients with mass-forming intrahepatic cholangiocarcinomas. Two readers independently interpreted enhancement patterns on arterial (globally high, rimlike), dynamic (washout, progressive), and hepatobiliary (target, nontarget) phase images. Dynamic enhancement was categorized as washout (hypoenhancement on later phase compared with arterial phase images) or progressive (persistent or gradually increased enhancement). Tumor enhancement ratio and tumor-to-liver signal difference curves were analyzed. The enhancement patterns were correlated with the extent of stromal fibrosis within the tumors., Results: Rimlike arterial enhancement (89%, reader 1; 84%, reader 2) and a progressive dynamic pattern (89%, both readers) were predominant. Tumor enhancement ratio increased gradually from the arterial to the equilibrium phase then decreased in the hepatobiliary phase, but the tumor signal intensities were lower than liver signal intensity in all phases. The two lesions that both readers considered to have globally high arterial enhancement and a washout dynamic pattern presented with minimal or scattered stromal fibrosis. Target appearance in the hepatobiliary phase (reader 1, 42%; reader 2, 47%) was more commonly seen in tumors with central stromal fibrosis (reader 1, p = 0.025; reader 2, p = 0.001)., Conclusion: Mass-forming intrahepatic cholangiocarcinomas may be characterized by rimlike enhancement and a progressive dynamic pattern on gadoxetate disodium-enhanced MR images, and these features seem related to the extent of stromal fibrosis in the tumor. Furthermore, mass-forming intrahepatic cholangiocarcinomas may have a pseudowashout pattern on gadoxetate disodium-enhanced MR images because of progressive background liver enhancement. Therefore, radiologists need to be aware of this pattern as a possible pitfall.

Objectives: This study aims to evaluate whether (18)F-FDG excretion patterns reflect renal function in malignant obstructive uropathy and to evaluate if these patterns predict internal ureteral stent success., Methods: One hundred twelve patients who underwent PET/CT for abdominal tumors and displayed hydronephrosis on CT and 59 patients who underwent PET/CT for cancer screening were included in a retrospective study. Hydronephrosis was graded by initial CT and correlated with visual analysis of (18)F-FDG renal parenchymal uptake and excretion patterns. Stent insertion was performed for 84 patients after PET. Follow-up CT was reviewed for hydronephrosis improvement., Results: There were 4 PET patterns in obstructive hydronephrosis which correlated linearly with hydronephrosis severity and serum creatinine levels. Patients with no parenchymal retention and renal excretion (PET pattern 1) showed 97% (28/29) hydronephrosis improvement after stent insertion, and patients with no parenchymal retention and no renal excretion showed 0% (0/9) hydronephrosis improvement after stent insertion. Multivariate analysis showed creatinine levels and PET pattern predicted stent success, but CT hydronephrosis did not., Conclusions: There are 4 PET patterns of obstructive hydronephrosis which correlated with hydronephrosis grade and creatinine levels. Some of these PET patterns can be useful in the prediction of hydronephrosis improvement after stent insertion. Recognition of these patterns in obstructive hydronephrosis may be helpful in improving patient prognosis and quality of life.

Purpose: To compare the breathhold, navigator-triggered, and free-breathing techniques in diffusion-weighted magnetic resonance imaging (MRI) for the evaluation of focal liver lesions on a 3.0T system., Materials and Methods: Fifty-two patients (36 men, 16 women; mean age, 56.4 years) with focal liver lesions underwent breathhold, navigator-triggered, and free-breathing diffusion-weighted imaging (DWI) of the liver on a 3.0 Tesla (T) system. All sequences were performed with b values of 50 and 800 s/mm(2) and identical parameters except for signal averages (two for navigator-triggered, one for breathhold, and four for free-breathing) and repetition time (3389 ms for navigator-triggered, 1500 ms for breathhold, and 4400 ms for free-breathing). A total of 74 lesions (50 malignant, 24 benign) were evaluated. The signal-to-noise ratios (SNR) of the liver and lesions, contrast-to-noise ratios (CNR) of each lesion, and ADC values of the liver and lesions were compared for each DWI sequence. The detection sensitivity and characterization accuracy were also compared., Results: The SNRs of the liver and lesions were significantly lower for breathhold DWI than for non-breathhold DWI (navigator-triggered and free-breathing DWI) for all b values. The CNRs of the lesions were also significantly lower for breathhold DWI than for non-breathhold DWI. The ADC values of the liver and focal lesions measured using the three DWI techniques were not significantly different and showed good correlation. For lesion detection and characterization, there were no significant differences between breathhold and non-breathhold DWI., Conclusion: Both breathhold and non-breathhold DWI are comparable for the detection or characterization of focal liver lesions at 3.0T; however, non-breathhold DWI provides higher SNR and CNR than breathhold DWI. In addition, although free-breathing and navigator-triggered DWI sequences show similar performance for 3.0T liver imaging, free-breathing DWI is more time efficient than navigator-triggered DWI., (Copyright © 2013 Wiley Periodicals, Inc.)

Background: Renal dysfunction is the most important factor to consider when predicting a patient's risk of developing contrast-induced nephropathy (CIN). Measurement of creatinine (Cr) via rapid point-of-care blood urea nitrogen/creatinine testing (POCT-BUN/Cr) to determine CIN risk could potentially reduce the time required to achieve an accurate diagnosis and to initiate and complete treatment in the emergency department (ED). The aim of our study was to compare the results of POCT-BUN/Cr and reference laboratory tests for BUN and serum Cr., Materials and Methods: A retrospective analysis of suspected stroke patients who presented between November 2009 and November 2010, and had BUN and Cr levels measured by POCT-BUN/Cr, and the reference laboratory tests performed with the blood sample which was transferred to the central laboratory by an air-shoot system. Two assays were conducted on the whole blood (POCT) and serum (reference) by trained technicians. The time interval from arrival at the ED to reporting of the results was assessed for both assays via a computerised physician order entry system., Results: The mean standard deviation (SD) interval from arrival at the ED to reporting of the results was 11.4 (4.9) min for POCT-BUN/Cr and 46.8 (38.5) min for the serum reference laboratory tests (p<0.001). Intra-class correlation coefficient (ICC) analysis demonstrated a high level of agreement (the consistency agreement) between POCT and the serum reference tests for both BUN (ICC=0.914) and Cr (ICC=0.980)., Conclusions: This study suggests that POCT-BUN/Cr results correlate well with those of serum reference tests in terms of BUN and Cr levels and, in turn, predicting CIN. POCT-BUN/Cr is easily performed with a rapid turnaround time, suggesting its use in the ED may have substantial clinical benefit.

As a result of recent developments in imaging modalities and wide spread routine medical checkups and screening, more incidental liver lesions are found frequently on US these days. When incidental liver lesions are found on US, physicians have to make a decision whether to just follow up or to undergo additional imaging studies for lesion characterization. In order to choose the next appropriate imaging modality, the diagnostic accuracy of each imaging study needs to be considered. Therefore, we tried to compare the accuracy of contrast-enhanced multidetector CT (MDCT) and Gd-EOB-DTPA-enhanced MRI for characterization of incidental liver masses. We included 127 incidentally found focal liver lesions (94 benign and 33 malignant) from 80 patients (M∶F = 45∶35) without primary extrahepatic malignancy or chronic liver disease. Two radiologists independently reviewed Gd-EOB-DTPA-enhanced MRI and MDCT. The proportion of confident interpretations for differentiation of benign and malignant lesions and for the specific diagnosis of diseases were compared. The proportion of confident interpretations for the differentiation of benign and malignant lesions was significantly higher with EOB-MRI(94.5%-97.6%) than with MDCT (74.0%-92.9%). In terms of specific diagnosis, sensitivity and accuracy were significantly higher with EOB-MRI than with MDCT for the diagnosis of focal nodular hyperplasia (FNH) and focal eosinophilic infiltration. The diagnoses of the remaining diseases were comparable between EOB-MRI and MDCT. Hence, our results suggested that Gd-EOB-MRI may provide a higher proportion of confident interpretations than MDCT, especially for the diagnosis of incidentally found FNH and focal eosinophilic infiltration.

Purpose: To define the histological characteristics of hepatocellular carcinomas (HCCs) showing atypical dynamic enhancement patterns on gadoxetic acid-enhanced dynamic magnetic resonance imaging (EOB-MRI)., Materials and Methods: We evaluated a total of 130 small (≤ 3 cm) HCCs from 114 patients that were surgically removed after EOB-MRI. Two radiologists blinded to the histological findings retrospectively classified the HCCs into typical or atypical lesions. Gross morphology, nuclear histological grade, presence of vascular invasion, and capsule formation and infiltration were compared between the two groups using Chi-square or Fisher tests., Results: Atypical dynamic enhancement patterns were seen in 23 HCCs (17.7%). None of the atypical HCC showed vascular invasion (P < 0.001). Atypical HCCs also showed more frequently smaller size (1.6 ± 0.6 cm versus 2.1 ± 0.6 cm, P = 0.001) with 86.9% (n = 20) of which 2 cm or less in diameter (P = 0.001), vaguely nodular appearance (56.5% vs 3.7%, P < 0.001), and nuclear grade I (69.6% versus 6.5%, P < 0.001), while less frequently showed capsule formation (26.1% versus 77.6%, P < 0.001) or capsular infiltration (16.7% versus 77.1%, P = 0.005)., Conclusion: Atypical HCCs on EOB-MRI may be characterized by the absence of vascular invasion, smaller (< 2 cm or less) size, vaguely nodular appearance, and well differentiation, and infrequent capsule formation or capsular infiltration., (Copyright © 2012 Wiley Periodicals, Inc.)

Background: Advanced and delicate laparoscopic techniques are usually required for safe and successful laparoscopic spleen-preserving distal pancreatectomy. The unique characteristics of robotic surgical system are thought to be useful for this minimally invasive procedure., Methods: From September 2007 to May 2011, patients who underwent robot-assisted, spleen-preserving, distal pancreatectomy for benign and borderline malignant tumors of the pancreas were retrospectively reviewed. Perioperative clinicopathologic surgical outcomes were evaluated., Results: Twenty-two patients were attempted for robot-assisted, spleen-preserving, distal pancreatectomy, and in 21 patients (95.5 %), the spleen was saved either by splenic vessels conservation (SVC; n = 17, 81 %) or by splenic vessels sacrifice (SVS; n = 4, 19 %). Seven patients were male and 15 were female with a mean age of 43.2 ± 15.2 years. Pathologic diagnosis included MCT in five patients, SCT in five, SPT in four, IPMT in three, NET in three, and other benign conditions in two. The mean operation time was 398.9 ± 166.3 min, but it gradually decreased as experiences were accumulated (Rsq = 0.223, p = 0.023). Intraoperative blood loss was 361.3 ± 360.1 ml, and intraoperative transfusion was required in four patients (18.1 %). A soft diet was given for 1.2 ± 0.4 days, and the length of hospital stay was 7.0 ± 2.4 days postoperatively. Clinically relevant pancreatic fistula was noted in two patients (9.1 %) but was successfully managed conservatively. Most patients (87.5 %) showed patency in conserved both splenic vessels, and only two patients (12.5 %) had partially or completely obliterated in splenic veins in the SVC-SpDP group. Partially impaired splenic perfusion was observed in one patient in the SVS-SpDP group. The perfusion defect area decreased without any clinical symptom after 4 months., Conclusions: The robotic surgical system is thought to be beneficial for improving the spleen-preservation rate in laparoscopic distal pancreatectomy. Robot-assisted approach can be chosen for patients who require spleen-preserving distal pancreatectomy.

Objective: The purpose of our study was to assess the relationship between time intervals of CT examinations and the stages of hepatocellular carcinomas (HCCs) detected during the surveillance of patients with liver cirrhosis., Materials and Methods: In this study, 73 patients with 93 HCCs (reference standard: surgery, n=7 [8 HCCs]; biopsy, n=2 [3 HCCs]; imaging criteria, n=64 [82 HCCs]) who showed no evidence of HCC on prior CT examinations were included. Patients were stratified into three groups based on the time interval between the two CT examinations: groups A (interval≤1 year, n=21), B (interval between 1 and 2 years, n=25), and C (interval≥2 years, n=27). Tumor stages according to the American Joint Committee on Cancer (AJCC), the Barcelona Clinic Liver Cancer (BCLC) staging system, and the Milan criteria were evaluated retrospectively by two reviewers. The Fisher exact test was used to compare tumor stages. Spearman correlation coefficients were used to assess the correlation between the CT interval and tumor size., Results: One (4%) HCC in group B and four (15%) HCCs in group C were larger than 5 cm in diameter, whereas no tumor was larger than 3 cm in diameter in group A. There was no difference in tumor diameter between groups, but tumor size was positively correlated with time interval between examinations (Spearman correlation coefficient, 0.472; p<0.001). In group A, 19 (90%) patients had cancers categorized as T1, and the remaining patients had cancers categorized as T2. In group B, one (4%) patient had a cancer that was categorized as T3b according to the AJCC classification, in the intermediate stage according to the BCLC classification, and above the Milan criteria. In group C, three (11%) patients had T3b cancers, and five had cancers in either intermediate or higher stage and above the Milan criteria., Conclusion: HCC detected on CT performed within 1 year of a negative examination was at a curable stage in patients with liver cirrhosis.

Objective: The aim of this study was to determine the registration error of an ultrasound (US) fusion imaging system during an ex vivo study and its clinical value for percutaneous radiofrequency ablation (pRFA) during an in vivo study., Materials and Methods: An ex vivo study was performed using 4 bovine livers and 66 sonographically invisible lead pellets. Real-time CT-US fusion imaging was applied to assist the targeting of pellets with needles in each liver; the 4 sessions were performed by either an experienced radiologist (R1, 3 sessions) or an inexperienced resident (R2, 1 session). The distance between the pellet target and needle was measured. An in vivo study was retrospectively performed with 51 nodules (42 HCCs and 9 metastases; mean diameter, 16 mm) of 37 patients. Fusion imaging was used to create a sufficient safety margin (>5 mm) during pRFA in 24 nodules (group 1), accurately target 21 nodules obscured in the US images (group 2) and precisely identify 6 nodules surrounded by similar looking nodules (group 3). Image fusion was achieved using MR and CT images in 16 and 21 patients, respectively. The reablation rate, 1-year local recurrence rate and complications were assessed., Results: In the ex vivo study, the mean target-needle distances were 2.7 mm±1.9 mm (R1) and 3.1±3.3 mm (R2) (p>0.05). In the in vivo study, the reablation rates in groups 1-3 were 13%, 19% and 0%, respectively. At 1 year, the local recurrence rate was 11.8% (6/51). In our assessment of complications, one bile duct injury was observed., Conclusion: US fusion imaging system has an acceptable registration error and can be an efficacious tool for overcoming the major limitations of US-guided pRFA., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Objective: The purpose of our study was to evaluate interobserver variability between the radiologist and emergency physician in detecting blunt liver trauma by conventional and contrast-enhanced ultrasound (US) (CEUS)., Methods: We created 20 sites of blunt liver trauma in rabbits and performed conventional US and CEUS on the animals. A radiologist and an emergency physician independently evaluated the degree of liver trauma. Using contrast-enhanced computed tomography as a reference standard, the diagnostic performance of US and CEUS was calculated. Interobserver variability between radiologist and emergency physician was compared before and after contrast enhancement of US., Results: Overall sensitivity and specificity for detecting liver trauma on conventional US, regardless of the degree of trauma, were 61.1% and 100% for the radiologist and 50% and 100% for the emergency physician. On CEUS, the sensitivity and specificity were 94.4% and 100% for both the radiologist and emergency physician. The interobserver agreement between emergency physician and radiologist increased from 0.867 to 0.955 after contrast enhancement on US., Conclusions: Contrast-enhanced US may permit a more accurate diagnosis for liver trauma than conventional US by both the radiologist and emergency physician. Contrast-enhanced US may also reduce interobserver variability for this diagnosis., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Objectives: To investigate the effectiveness of qualitative diffusion-weighted imaging (DWI), subtraction of unenhanced from arterial phase images, and hepatobiliary phase (HBP) images in estimating the histopathological grade of hepatocellular carcinoma (HCC)., Methods: We retrospectively reviewed gadoxetic acid-enhanced magnetic resonance images of 175 patients with 201 surgically resected HCCs. The signal intensity and its relationship with histopathological grade were assessed for each sequence and a combination of sequences., Results: There was a tendency towards higher grades in tumours showing restricted diffusion on DWI (P < 0.001) or arterial enhancement on subtraction imaging (P < 0.001), but not hepatocyte-defect on HBP images (P = 0.33). When lesions were divided into three groups based on combined findings on DWI and subtraction imaging, a linear trend was observed between group and grade (P < 0.001). The positive predictive value (PPV) of the combination of no restricted diffusion and no arterial enhancement in predicting well-differentiated HCC was 100%, higher than the PPV of individual findings on DWI (74%) or subtraction imaging (81%)., Conclusions: DWI and subtraction imaging are helpful for predicting the histopathological grade of HCC, especially when the two sequences are considered together., Key Points: • Predicting the histopathological grade of hepatocellular carcinoma (HCC) preoperatively is important. • Diffusion-weighted imaging (DWI) and subtraction imaging are recently developed MR techniques. • Retrospective study showed DWI and subtraction imaging helps predict HCC grades. • Management of patients with HCC becomes more appropriate.

Background: Pretreatment identification of the sentinel lymph nodes (SLNs) in gastric cancer patients may have great advantages for minimally invasive treatment. No reliable method for the detection of SLNs during the pretreatment period in gastric cancer has been established. The aim of this study was to determine whether computed tomographic (CT) lymphography using nanoscale iodized oil emulsion via endoscopic submucosal injection can visualize LNs., Methods: Five dogs underwent CT lymphography after endoscopic submucosal injection of 2 ml of a nanoscale iodized oil emulsion. CT images were taken before and 30, 90, and 210 min after contrast injection. Intraoperative SLN detection was performed using endoscopically injected indocyanine green lymphography for comparison., Results: Computed tomographic lymphography with nanoscale iodized oil emulsion enabled the visualization of 19 enhanced LNs (mean = 3.8/dog, range = 3-6) with a 100% SLN detection rate. The locations of the SLNs were the lesser curvature (n = 7), greater curvature (n = 1), infrapyloric (n = 3), and left gastric (n = 8) areas. Contrast enhancement of SLNs continuously increased and peaked after 210 min at 142.4 ± 42.3 HU. No green LNs were visualized in the three locations that were detected by CT lymphography. However, no additional LNs were visualized using the dye method. The concordance rate based on the LNs between the SLNs on CT lymphography and the green LNs using the ICG method was 84% (16/19), whereas the concordance rate of the stations identified by CT lymphography and the dye method was 78.6% (11/14)., Conclusions: Computed tomographic lymphography using nanoscale iodized oil emulsion is a promising tool for preoperative SLN detection for early gastric cancer if the biological safety of the nanoscale iodized oil emulsion can be established.

Background: To evaluate hepatocellular carcinoma (HCC) that developed in patients with no evidence of a tumor during a prior ultrasound (US) performed within 1 year of the diagnosis., Methods: We retrospectively analyzed data for 100 consecutive patients with liver cirrhosis who had undergone US within 1 year prior to HCC diagnosis and who showed no liver lesions on the previous US. Size and T stage of HCC were assessed as well as whether patients met surgical criteria for liver transplantation as HCC treatment [Milan or University of California at San Francisco (UCSF) criteria]., Results: The mean interval between the negative and diagnostic scans was 5 months, 13 days. HCC presented as a single nodule in 69 patients (size, 0.8-8.0 cm), as two or more nodules in 18 patients, and as the diffuse form of HCC in 13 patients. HCC presented as a small tumor (<3 cm) in 48 patients. T stages were: T1 in 26 patients, T2 in 45, T3 in 18, and T4 in 11. The Milan criteria were met in 79 patients. Eighty-five patients fulfilled the UCSF., Conclusion: Patients may present with advanced HCC, even if sonographic findings were negative within 1 year prior to diagnosis., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Portal annular pancreas is one of the pancreatic fusion anomalies in which the uncinate process of the pancreas extends to fuse with the dorsal pancreas by encircling the portal vein or superior mesenteric vein. We report two consecutive patients with portal annular pancreas. The first case is a 71-year-old male patient who underwent a pancreaticoduodenectomy for intraductal papillary mucinous neoplasm in the head of pancreas. His preoperative computed tomography scan showed the suprasplenic type portal annular pancreas. The second case is a 74-year-old female patient who underwent a laparoscopic anterior radical antegrade modular pancreatosplenectomy (RAMPS) for pancreatic body cancer. In operative finding, portal confluence (superior mesenteric vein-splenic vein-portal vein) was encased with the uncinate process of pancreas in both cases. Therefore, they required pancreatic division at the pancreatic neck portion twice. During the postoperative period, grade B and A, respectively, postoperative pancreatic fistulas occurred and were controlled by conservative management. Surgeons need to know about this rare pancreatic condition prior to surgical intervention to avoid complications, and to provide patients with well-designed, case-specific pancreatic surgery.

Purpose: Fitz-Hugh-Curtis Syndrome (FHCS) is a clinical entity characterized by inflammation of the liver capsule associated with genital tract infection. The aim of this study is to provide physicians with clinical suggestions for diagnostic approaches based on a series of patients who were diagnosed with FHCS., Materials and Methods: We conducted a retrospective study of patients who were diagnosed with FHCS after presenting to the emergency department (ED). The symptoms, physical examinations, laboratory findings, radiological findings, and progress of the patients were reviewed., Results: During the four-year study period, a total of 82 female patients received a final diagnosis of FHCS in the ED. Chlamydia trachomatis was identified as a pathogen in 89% of the patients. Their clinical characteristics and laboratory findings were described. Fifty-two patients (63.4%) were admitted to the hospital. All of the admitted patients improved after treatment combining antibiotic therapy with conservative care., Conclusion: FHCS should be considered as a differential diagnosis for female patients of childbearing age with right upper abdominal pain. Timely diagnosis using biphasic computed tomography (CT) with arterial and portal phases may help ensure adequate medical treatment as well as avoid invasive procedures.

Purpose: To compare the diagnostic performance of a diffusion-weighted imaging (DWI) dataset and a gadofluorine M-enhanced imaging dataset for identifying lymph node (LN) metastases in a rabbit rectal cancer model., Materials and Methods: VX2 carcinomas were injected into the rectum of 26 rabbits. Four weeks later, T2-weighted imaging (T2WI), pre-T1WI, DWI, and post-T1WI were performed. Two radiologists independently reviewed the DWI set (T2WI, pre-T1WI, DWI) and the gadofluorine M set (T2WI, pre- and post-T1WI) and recorded their confidence scores for LN metastasis on a per-LN basis. Receiver operating characteristic (ROC) analysis was performed to compare the area under the ROC curve (A(z) ) of the two imaging sets. Histopathologic results were used as the reference standard., Results: The A(z) and sensitivity of the gadofluorine M set were comparable to those of the DWI set (A(z) , for reader 1, 0.849, 0.829, P = 0.571; for reader 2, 0.923, 0.876, P = 0.212; sensitivity, for reader 1, 97%, 97%; for reader 2, 97%, 92%, P = 0.304). The specificity of the former was greater than that of the latter (for reader 1, 65%, 53%, P = 0.0003; for reader 2, 81%, 68%, P = 0.01)., Conclusion: Gadofluorine M-enhanced images provided greater specificity than DWI for identifying LN metastases, whereas the A(z) and sensitivity of the former were comparable to those of the latter., (Copyright © 2012 Wiley Periodicals, Inc.)

Objective: To assess whether reticular hypointensity on hepatobiliary phase images of gadoxetic acid-enhanced magnetic resonance imaging (EOB-MRI) is a diagnostic finding of sinusoidal obstruction syndrome (SOS) in patients with hepatic metastases who have undergone chemotherapy., Methods: We retrospectively analysed EOB-MRI of 42 patients who had undergone chemotherapy before hepatic resection of colorectal hepatic metastases. Two radiologists, who were unaware of whether or not the patients had SOS, reviewed the hepatobiliary phase images to determine the presence of hypointense reticulation in the liver using a 5-point scale. The sensitivity, specificity and area under the receiver operating characteristics curve (A(z)) were calculated for each reviewer., Results: The sensitivity, specificity and A(z) for the diagnosis of SOS were 75%, 100% and 0.957 for reader 1 and 75%, 96.2% and 0.936 for reader 2, respectively. In one patient who received a false-positive diagnosis by one reader, there was sinusoidal fibrosis on histological examination, but not diagnostic for SOS. False-negative diagnosis occurred in four patients for both readers; histology of these patients showed minimal and localised sinusoidal congestion and fibrosis., Conclusions: Reticular hypointensity on hepatobiliary phase images of EOB-MRI is highly specific for the diagnosis of SOS in patients with treated colorectal hepatic metastases., Key Points: Gadoxetic acid enhanced magnetic resonance imaging (EOB-MRI) can identify the sinusoidal obstruction syndrome (SOS). The diagnosis can be achieved with high specificity and good interobserver agreement. SOS typically demonstrates diffuse hypointensity on hepatobiliary phase images on EOB-MRI. EOB-MRI may be falsely negative in patients with minimal degree of SOS.

Unlabelled: We determined whether suppression of sclerostin levels by estrogen treatment was mediated by anti-resorptive effect. Raloxifene, but not bisphosphonates, suppressed circulating sclerostin concentration, suggesting that sclerostin may mediate the action of estrogen on bone metabolism, independently of their anti-resorptive effects., Introduction: Circulating sclerostin concentrations are higher in postmenopausal than in premenopausal women, and estrogen treatment suppresses sclerostin levels in both men and women. We determined whether anti-resorptives may suppress the circulating sclerostin levels., Methods: We conducted a retrospective observational study. Eighty postmenopausal women were treated with raloxifene for 19.4 ± 7.7 months (n = 16), bisphosphonates for 19.2 ± 6.7 months (n = 32), or were untreated (n = 32) for 17.1 ± 4.6 months. Plasma sclerostin concentrations were measured before and after treatment., Results: Plasma sclerostin levels after treatment were significantly lower in the raloxifene than in the control group (55.8 ± 23.4 pmol/l vs. 92.1 ± 50.4 pmol/l, p = 0.046), but were similar between the bisphosphonate and control groups. Relative to baseline, raloxifene treatment markedly reduced plasma sclerostin concentration (-40.7 ± 22.8%, p < 0.001), with respect to both control (-7.5 ± 29.1%) and bisphosphonate (-3.1 ± 35.2%) groups. Changes in bone-specific alkaline phosphatase and osteocalcin levels showed reverse associations with sclerostin concentration changes in the raloxifene (γ = -0.505, p = 0.017) and control (γ = -0.410, p = 0.020) groups., Conclusions: Raloxifene, but not bisphosphonates, significantly suppressed circulating sclerostin concentration, suggesting that sclerostin may mediate the action of estrogen on bone metabolism, independently of their anti-resorptive effects.

Background: Margin-negative pancreatectomy provides only chance to cure pancreatic cancer. However, borderline resectable pancreatic cancer (BRPCa) has the risk of incomplete palliative resection., Materials and Methods: We retrospectively reviewed 32 patients with BRPCa who underwent a pancreatectomy following preoperative chemoradiation therapy (CCRT (+)/Px group) and compared these patients with those with resectable pancreatic cancer (RPCa) who underwent pancreatectomy without preoperative CCRT (CCRT (-)/Px group, n=104)., Results: Eighteen patients (56.2%) showed more than 50% significant pathological response to CCRT. The degree of pathological responses showed a positive relationship between final pT stage (p=0.075). More frequent vascular resection (p<0.001), transfusion (p=0.076), and longer operation time were observed in the CCRT(+)/Px group. However, similar R0 resection rates (p=0.272), lower pT stage (p<0.001), smaller number of metastastic lymph nodes (p=0.002), and lower incidence of lymph node metastasis (p=0.032) were noted in the CCRT(+)/Px group. The overall disease-specific survival were similar (median survival, 30.5 months (95% CI; 23.6-37.4) vs. 26.3 months (95% CI; 15.9-36.7), p=0.709), and no statistical differences in cancer recurrence risks were noted between the two groups (p=0.505)., Conclusion: Pancreatectomy following preoperative neoadjuvant CCRT can be a potential strategy for margin-negative resection in BRPCa patients.

Purpose: To determine whether peritumoral hypointensity seen on hepatobiliary phase images of preoperative gadoxetate disodium-enhanced magnetic resonance imaging (EOB-MRI) is useful for predicting microvascular invasion of hepatocellular carcinoma (HCC)., Materials and Methods: This study was approved by the Institutional Review Board. In all, 104 HCC masses in 104 patients who had undergone EOB-MRI and liver surgery within 1 month after EOB-MRI were evaluated. Two radiologists independently recorded the presence of a peritumoral hypointensity on hepatobiliary phase. Interobserver agreement was assessed and consensus records were used. Tumor size was measured. A chi-square test and independent t-test were used for univariate analysis. Multiple logistic regression was performed to determine factors for predicting microvascular invasion. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of peritumoral hypointensity were calculated., Results: Sixty HCCs had microvascular invasion and 44 did not. Interobserver agreement in determining peritumoral hypointensity was excellent (κ = 0.83). By univariate analysis, peritumoral hypointensity and tumor size were significant for predicting microvascular invasion of HCC. On multiple logistic regression analysis, only peritumoral hypointensity was significant in predicting microvascular invasion of HCC (P = 0.013). The sensitivity, specificity, PPV, and NPV of peritumoral hypointensity were 38.3%, 93.2%, 88.5%, and 52.6%, respectively., Conclusion: Peritumoral hypointensity on the hepatobiliary phase of EOB-MRI is not sensitive but has high specificity for predicting microvascular invasion of HCC., (Copyright © 2011 Wiley Periodicals, Inc.)

Objective: To quantify the cumulative effective dose (cED) of radiation due to repeated CT and PET/CT examinations after curative resection of gastric cancer and to assess the lifetime attributable risk (LAR) estimates based on Biological Effects of Ionizing Radiation VII models., Subjects and Methods: Patients who underwent a curative resection for gastric cancer between January 2006 and December 2006 and were followed-up until May 2010 were included in this study. The cED was calculated by using the dose-length product values and conversion factors for quantitative risk assessment of radiation exposure. cED and LAR were compared between early and advanced gastric cancer patients and among American Joint Committee on Cancer TNM stage groups (stage I, II, and III). The nonparametric Mann-Whitney U and Kruskal-Wallis tests, followed by a post-hoc analysis with Bonferroni adjustment, were employed as part of the statistical analysis., Results: The overall median cED was 57.8 mSv (interquartile range [IQR], 43.9-74.7). The cED was significantly higher in the advanced (median, 67.0; IQR, 49.1-102.3) than in the early gastric cancer group (median, 52.3; IQR, 41.5-67.9) (p < 0.001), and increased as the TNM stage increased. For radiation exposure, 62% of all patients received an estimated cED of over 50 mSv, while 11% of patients received over 100 mSv. The median LAR of cancer incidence was 0.28% (IQR, 0.20-0.40) and there were significant differences between the early gastric cancer and advanced gastric cancer group (p < 0.001) as well as among the three TNM stage groups (p = 0.015). The LAR of cancer incidence exceeded 1% in 2.4% of the patients., Conclusion: The cED increases proportionally along with tumor stage and, even in early gastric cancer or stage I patients, cED is much higher than that found among the general population. Considering the very good prognosis of early gastric cancer after curative surgery, the cED should be considered when designing a postoperative follow-up CT protocol.

Objectives: The purpose of this study was to investigate the ability of sonography to identify acute epiglottitis in the emergency department., Methods: Fifteen patients with a final diagnosis of acute epiglottitis from indirect laryngoscopy by an otolaryngologist were enrolled in the study. To compare the normal epiglottis and acute epiglottitis, 15 healthy volunteers were assigned to a control group. The sonographic appearances of the epiglottitis and the pre-epiglottic space were recorded. The anteroposterior diameter of the epiglottis at the midpoint and both edges in a transverse view was measured in all participants., Results: A statistically significant difference (P < .001) was observed in the anteroposterior diameter of the epiglottis at the midpoint and both lateral edges between the patients and healthy volunteers. However, there was overlap in the ranges for the midpoint but no overlap in both lateral edges between groups. The upper-limit value for the healthy control group was 3.2 mm at both lateral edges, whereas the cutoff values of the right and left edges were 3.7 and 3.6 mm, respectively, according to the lower-limit value for the epiglottitis group., Conclusions: The anteroposterior diameter of the epiglottis was significantly different between the patients with epiglottitis and the healthy volunteers. Because of this significant difference in the anteroposterior diameter of the epiglottis, sonography can be used as a rapid, noninvasive, and effective diagnostic tool for identifying cases of epiglottitis in the emergency department.

Objective: To assess the diagnostic accuracy of multi-detector-row computed tomography (MDCT) for the detection of ampullary adenomas or adenocarcinomas in situ., Materials and Methods: We retrospectively reviewed 21 computed tomography (CT) images from 20 patients with ampullary tumors, and 22 CT images from 22 patients without periampullary tumor. Three radiologists blindly and independently reviewed CT images. The sensitivities and specificities for identification of ampullary masses were calculated in all cases and in cases with adequate duodenal distension. The sensitivities and specificities for the diagnosis of ampullary tumors were calculated using the following criteria: identification of mass alone; presence of extrahepatic bile duct (EBD) dilation or identification of mass; presence of pancreatic duct (PD) dilation or identification of mass. Paired t-tests were performed to assess differences in mean values., Results: The mean sensitivity and specificity of MDCT for the detection of an ampullary mass in all cases were 47.6% and 86.4%, and in cases with adequate duodenal distension, 66.7% (p=0.07) and 80.5% (p=0.32), respectively. When the presence of EBD dilation or identification of mass were used as criteria, the mean sensitivity and specificity were 73.0% (p=0.03) and 60.6% (p=0.03), respectively. When presence of PD dilation or identification of mass were used as criteria, the mean sensitivity and specificity were 47.6% and 81.8% (p=0.23)., Conclusions: MDCT is moderately accurate for the diagnosis of ampullary adenoma or adenocarcinoma in situ. When EBD dilation or identification of mass were used as criteria, the sensitivity can be improved., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

Unlabelled: The association between serum osteocalcin levels and metabolic syndrome (MS) in Korean individuals was investigated. Serum osteocalcin levels are significantly lower in subjects with MS than in those without the disease, regardless of glucose metabolism., Introduction: Osteocalcin was recently shown to affect energy metabolism. In the present study, we investigated the possible association between serum osteocalcin concentrations and MS., Methods: A cross-sectional community-based survey was conducted. Serum osteocalcin, type 1 collagen C-telopeptide (CTX) and total alkaline phosphatase (ALP) concentrations were determined in 567 subjects. MS was defined according to NCEP-ATP III criteria., Results: Serum osteocalcin concentrations were significantly lower in subjects with MS than those without MS in postmenopausal women (18.923 ± 7.685 vs 22.513 ± 7.344 ng/ml, P<0.001) and marginally lower in subjects with MS than those without MS in men (14.550 ± 5.090 vs 16.125 ± 4.749 ng/ml, P=0.086) after adjustment for age and BMI. Further controlling with CTX or ALP did not affect this association in postmenopausal women; however, controlling with osteocalcin abolished the association between CTX and MS. Significant differences in serum osteocalcin levels by MS status were noted in subjects with normal glucose tolerance as well as those with abnormal glucose tolerance (P=0.032 and P<0.001, respectively). Compared with subjects with the highest quartile of osteocalcin, those in the lower quartile groups (Q1-Q3) had significantly increased risks of MS (ORs=5.18, CIs=1.15-23.42) in men. In postmenopausal women, the ORs for MS were significantly higher in the lowest quartile than in the highest quartile (ORs=5.25, CIs=2.42-11.36)., Conclusions: These findings suggest that osteocalcin is associated with MS, independently of glucose metabolism.

Objective: To define diagnostic criteria for differentiating malignant ampullary carcinoma from benign ampullary obstruction on MR imaging., Materials and Methods: Nineteen patients with ampullary carcinoma and 22 patients with benign ampullary obstruction were enrolled. At the first session, two radiologists independently evaluated specific imaging findings, and then reached consensus decisions. At the second session, another two radiologists, who were informed about useful differentiation criteria based on the results from the first session, reviewed images and determined the causes of ampullary obstruction. Sensitivity and specificity were calculated for each interpretation session, and the Cohen κ statistic was used to evaluate interobserver agreement., Results: Findings of the presence of an ampullary mass (P<0.001), papillary bulging (P<0.001), irregular (P=0.021) and asymmetric (P<0.001) common bile duct (CBD) narrowing, and proportional biliary dilatation (P<0.001) were more commonly seen in patients with an ampullary carcinoma. The sensitivity and specificity of the first session were 84.2% and 86.4% after consensus. The sensitivity increased to 100% for both the readers at the second session, while the specificity decreased to 63.6% and 59.1%, respectively., Conclusions: Identification of an ampullary mass, papillary bulging, irregular and asymmetric narrowing of the CBD, or proportional biliary dilatation may improve the diagnosis of ampullary carcinoma in patients with ampullary obstruction., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

Pancreatic tumors can be classified by their morphologic features on CT. The subtypes include solid tumors, mixed cystic and solid lesions, unilocular cysts, multilocular cystic lesions, and microcystic lesions. Endoscopic US and MRI can provide detailed information for classifying pancreatic lesions. Each subtype has different kinds of tumors and malignant potential, thus the classification can be useful for a better differential diagnosis and treatment planning. For this purpose, we suggest an appropriate modified classification system by using the imaging features of pancreatic tumors with an emphasis on CT findings and illustrate various findings of typical and atypical manifestations.

Purpose: To retrospectively compare the diagnostic accuracy for the detection of colorectal liver metastases between gadoxetic acid-enhanced MRI (EOB-MRI) and diffusion-weighted imaging (DWI) on 3.0 Tesla (T) system, and then to determine whether a combination of the two techniques may improve the diagnostic performance., Materials and Methods: Forty-seven patients underwent MR imaging at 3.0T, including DWI (DWI set) and dynamic and hepatobiliary phase EOB-MRI (EOB set) for the preoperative evaluation of colorectal liver metastases. All suspicious metastases were confirmed by hepatic surgery. Two blinded readers independently reviewed three different image sets, which consisted of DWI set, EOB set, and combined set. The accuracy was assessed by the area (Az) under the alternative-free response receiver operating characteristic curve, and the sensitivity and positive predictive value (PPV) were calculated., Results: We found a total of 78 confirmed colorectal liver metastases in 42 of 47 patients. Each reader noted higher diagnostic accuracy of combined set of EOB-MRI and DWI than DWI set and EOB set, without statistical significance. Regardless of the size of colorectal liver metastasis, each reader detected significantly more metastases on combined set than on DWI set, and PPV was significantly higher with DWI set than with EOB set or with combined set for one reader., Conclusion: EOB-MRI was more useful for the detection of colorectal liver metastases, while DWI was more useful for their characterization. The combination of EOB-MRI and DWI showed significantly higher accuracy and sensitivity for the preoperative detection of small colorectal liver metastases than DWI., (Copyright © 2011 Wiley-Liss, Inc.)

Unlabelled: In a candidate gene association study, we found that SMAD2 promoter alleles and haplotypes were significantly associated with bone mineral density (BMD) at the lumbar spine and various proximal femur sites. Our results suggest that SMAD2 polymorphisms may be one of genetic determinants of BMD in postmenopausal women., Introduction: SMAD2, which is the specific intracellular transducer of TGF-ß, is thought to participate in bone metabolism by playing a critical role in the development and function of osteoclasts and osteoblasts. We performed association analyses of the genetic variation in SMAD2 to ascertain the contribution of this gene to BMD and risk of osteoporotic fracture., Methods: We selected three SMAD2 promoter single-nucleotide polymorphisms (SNPs) based on heterozygosity and validation status. Postmenopausal Korean women (n = 1,329) were genotyped for these SNPs, and their BMD and risk of fractures were assessed. BMD at the lumbar spine and proximal femur was measured using dual-energy X-ray absorptiometry. P values were corrected for multiple testing by the effective number of independent marker loci (P (cor))., Results: We found that SMAD2 -35302C>T, -34952A>G, and ht2 were significantly associated with BMD at both the lumbar spine and femur neck (P (cor) = 0.020-0.046), whereas SMAD2 -36201A>G and ht1 affected the femur neck BMD (P (cor) = 0.018-0.031). The genetic effects of these three polymorphisms on BMD at the lumbar spine and femur neck were risk-allele dependent in additive model. The three polymorphisms and two hts were also significantly associated with BMD at other proximal femur sites, such as the total femur, trochanter, and femur shaft (P (cor) = 0.001-0.046). However, none of the polymorphisms or hts was associated with an increased risk of fracture., Conclusions: Our results suggest that SMAD2 polymorphisms may be one of genetic determinants of BMD in postmenopausal women.