Kyoung Doo Song

Samsung Medical Center, Sŏul, Seoul, South Korea

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Publications (40)84.1 Total impact


  • No preview · Article · Feb 2016 · American Journal of Roentgenology
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    ABSTRACT: Background & aims: To investigate the differences in mechanical effects and ablation zone between radiofrequency (RF) ablation with and without Sonazoid uptake in an in vivo rabbit liver model. Methods: Our study was approved by the Institutional Animal Care and Use Committee. Twenty-five rabbits were randomly allotted to one of five ablation durations (i.e., 1, 2, 3, 6, and 12 min). For each rabbit, RF ablation was performed twice, before and 10 min after Sonazoid administration (i.e. control group vs. Sonazoid group) using a 1-cm internally-cooled electrode (40W) equipped with a parallelly-fixed pressure-monitoring device. During ablation, a "popping" sound was perceived and recorded along with tissue pressure changes and RF ablation parameters. Then, the ablation volume and microscopic changes were compared. Results: Popping sounds were more frequently perceived in the control group (21/25 vs. 1/25, P<0.001). The time to first pressure peak was shorter in the Sonazoid group (22.3±1.1s vs. 46.3±4.4s, P<0.001) with similar pressures (39.8±4.2 mmHg vs. 35.6±4.1 mmHg, P=0.350). Time to first roll-off and mean power output were significantly less in the Sonazoid group (17.6±1.2s vs. 71.2±8.2s, P<0.001; 9.4±0.3 W vs. 12.8±0.5 W, P<0.001). Consequently, the Sonazoid group had lower total energy and ablation volumes for all durations. Microscopically, the control group showed larger confluent disruptions, whereas the Sonazoid group showed many smaller disruptions scattered throughout the ablation zones. Conclusions: RF ablation after Sonazoid uptake induces a smaller ablation zone than conventional RF ablation. However, it appears to ablate the liver tissue with less mechanical effects. This article is protected by copyright. All rights reserved.
    No preview · Article · Feb 2016 · Liver international: official journal of the International Association for the Study of the Liver
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    ABSTRACT: Purpose: To evaluate the diagnostic performance of rectal MRI in predicting candidates for local excision (LE; ypT0-1N0) after neoadjuvant chemoradiation therapy (CRT) in patients with rectal cancer. Materials and methods: The institutional review board approved our retrospective study and waived informed consent. Inclusion criteria were as follows: patients with pathologically confirmed mid to lower rectal cancer (cT3NxM0 before neoadjuvant CRT) who underwent neoadjuvant CRT and had MRI performed at 3T before and after neoadjuvant CRT. A total of 168 patients met the study criteria between 2011 and 2012. Two observers independently assessed tumor and nodal stages on MR images obtained after neoadjuvant CRT. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy for identifying a candidate for LE (ypT0-1N0) were calculated. Interobserver agreement was assessed with kappa value. Predictive factors for ypT0-1N0 were evaluated by logistic regression models. Results: MRI had relatively high accuracy, specificity, and NPV (85.9%, 93.8%, and 88.9% for observer 1 and 85.3%, 96.1%, and 86.6% for observer 2), moderate PPV (71.4% and 76.2%), and relatively low sensitivity (57.1% and 45.7%) for predicting ypT0-1N0. The interobserver agreement was fair (kappa value = 0.593). Carcinoembryonic antigen levels after neoadjuvant CRT and the maximal extramural depth of tumor spread were significant predictors of ypT0-1N0 (P = 0.037 and 0.017, respectively). Conclusion: MRI after neoadjuvant CRT can predict a candidate for LE (ypT0-1N0) after neoadjuvant CRT with moderate PPV and relatively high NPV. J. Magn. Reson. Imaging 2016.
    No preview · Article · Jan 2016 · Journal of Magnetic Resonance Imaging
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    ABSTRACT: Objectives: To develop and validate a prediction model using magnetic resonance imaging (MRI) for local tumour progression (LTP) after radiofrequency ablation (RFA) in hepatocellular carcinoma (HCC) patients. Methods: Two hundred and eleven patients who had received RFA as first-line treatment for HCC were retrospectively analyzed. They had undergone gadoxetic acid-enhanced MRI before treatment, and parameters including tumour size; margins; signal intensities on T1-, T2-, and diffusion-weighted images, and hepatobiliary phase images (HBPI); intratumoral fat or tumoral capsules; and peritumoural hypointensity in the HBPI were used to develop a prediction model for LTP after treatment. This model to discriminate low-risk from high-risk LTP groups was constructed based on Cox regression analysis. Results: Our analyses produced the following model: 'risk score = 0.617 × tumour size + 0.965 × tumour margin + 0.867 × peritumoural hypointensity on HBPI'. This was able to predict which patients were at high risk for LTP after RFA (p < 0.001). Patients in the low-risk group had a significantly better 5-year LTP-free survival rate compared to the high-risk group (89.6 % vs. 65.1 %; hazard ratio, 3.60; p < 0.001). Conclusion: A predictive model based on MRI before RFA could robustly identify HCC patients at high risk for LTP after treatment. Key points: • Tumour size, margin, and peritumoural hypointensity on HBPI were risk factors for LTP. • The risk score model can predict which patients are at high risk for LTP. • This prediction model could be helpful for risk stratification of HCC patients.
    No preview · Article · Jan 2016 · European Radiology
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    ABSTRACT: Objectives: To identify predictors for the discrimination of intrahepatic cholangiocarcinoma (IMCC) and combined hepatocellular-cholangiocarcinoma (CHC) from hepatocellular carcinoma (HCC) for primary liver cancers on gadoxetic acid-enhanced MRI among high-risk chronic liver disease (CLD) patients using classification tree analysis (CTA). Methods: A total of 152 patients with histopathologically proven IMCC (n = 40), CHC (n = 24) and HCC (n = 91) were enrolled. Tumour marker and MRI variables including morphologic features, signal intensity, and enhancement pattern were used to identify tumours suspicious for IMCC and CHC using CTA. Results: On CTA, arterial rim enhancement (ARE) was the initial splitting predictor for assessing the probability of tumours being IMCC or CHC. Of 43 tumours that were classified in a subgroup on CTA based on the presence of ARE, non-intralesional fat, and non-globular shape, 41 (95.3 %) were IMCCs (n = 29) or CHCs (n = 12). All 24 tumours showing fat on MRI were HCCs. The CTA model demonstrated sensitivity of 84.4 %, specificity of 97.8 %, and accuracy of 92.3 % for discriminating IMCCs and CHCs from HCCs. Conclusions: We established a simple CTA model for classifying a high-risk group of CLD patients with IMCC and CHC. This model may be useful for guiding diagnosis for primary liver cancers in patients with CLD. Key points: • Arterial rim enhancement was the initial splitting predictor on CTA. • CTA model achieved high sensitivity, specificity, and accuracy for discrimination of tumours. • This model may be useful for guiding diagnosis of primary liver cancers.
    No preview · Article · Dec 2015 · European Radiology
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    ABSTRACT: Background & aims: We investigated whether pre- or postablation serum alpha-fetoprotein (AFP) and des-gamma-carboxy prothrombin (DCP) levels can predict prognosis in patients with curative radiofrequency ablation (RFA) for hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). Methods: We retrospectively analyzed 412 patients with HBV-related single HCC treated with percutaneous RFA between January 2004 and December 2013. AFP and DCP levels were measured before (preablation) and 1 month after treatment (postablation). We assessed predictive factors for overall and recurrence-free survival. Results: On univariate analysis, Child-Pugh score, MELD score, platelet count, tumor size, Barcelona Clinic Liver Cancer (BCLC) stage, and pre- and postablation DCP were significant for overall survival; and age, Child-Pugh score, MELD score, platelet count, tumor size, Cancer of the Liver Italian Program (CLIP) score, BCLC stage, and pre- and postablation AFP and DCP were significant for recurrence-free survival. Multivariate analysis revealed significant differences in overall survival by MELD score and tumor size and in recurrence-free survival by BCLC stage. Among the tumor markers, postablation DCP was an independent prognostic factor for overall and recurrence-free survival (hazard ratio [HR], 3.438; 95% confidence interval [CI], 1.331-8.877; p = 0.011 and HR, 4.934; 95% CI, 2.761-8.816; p < 0.001, respectively). Postablation AFP was associated with recurrence-free survival (HR, 1.995; 95% CI, 1.476-2.697; p <0.001) but not overall survival. Conclusions: In patients with HBV-related HCC, postablation serum DCP is a useful biomarker for predicting survival and recurrence after curative RFA. This article is protected by copyright. All rights reserved.
    No preview · Article · Oct 2015 · Liver international: official journal of the International Association for the Study of the Liver
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    Kyoung Doo Song · Woo Kyoung Jeong

    Full-text · Article · Jun 2015 · Clinical and molecular hepatology
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    ABSTRACT: To investigate the early imaging findings and growth rate of pancreatic ductal adenocarcinoma (PDAC), and to assess whether MR imaging detects early PDAC better than CT. The institutional review board approved this retrospective study and waived the requirement for informed consent. Twenty-two patients were included, and two radiologists, by consensus, assessed the presence of focal lesions, interruption of the main pancreatic duct (MPD), MPD dilatation, and pancreatitis, volume doubling time (VDT) of PDAC on prediagnostic MR imaging. Two other observers independently reviewed three image sets (CT images, unenhanced MR images, and unenhanced and contrast-enhanced MR images) for the detection of early PDAC. Paired Wilcoxon signed rank test and receiver operating characteristic (ROC) curve analysis were used for statistical analyses. In 20 (90.9%) patients, prediagnostic MR exams showed abnormality, and all of them showed focal lesions on the first abnormal prediagnostic MR exams. Thirteen lesions (65%) showed no MPD interruption and one lesion (5%) was accompanied by pancreatitis. The mean VDT of PDAC was 151.7 days (range, 18.3-417.8 days). Diagnostic performance of unenhanced MR images (Az, 0.971-0.989) and combined unenhanced and contrast-enhanced MR images (Az, 0.956-0.963) was significantly better than that of CT images (Az, 0.565-0.583; p<0.01) for both observers, CONCLUSION: The most common early imaging finding of PDAC on prediagnostic MR exams was a focal lesion with no MPD interruption with a mean volume doubling time of five months. MR imaging was superior to CT for the detection of early PDAC. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
    No preview · Article · May 2015 · European journal of radiology
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    ABSTRACT: To compare the performance of the 15-gauge (G) internally cooled electrode with that of the conventional 17-G internally cooled electrode. A total of 40 (20 for each electrode) and 20 ablation zones (ten for each electrode) were made in extracted bovine livers and in in vivo porcine livers, respectively. Technical parameters, three dimensions [long- (Dl), vertical- (Dv), and short-axis diameter (Ds)], volume, and the circularity (Ds/Dl) of ablation zone were compared. Total delivered energy was higher in the 15-G group than in the 17-G group in both ex vivo and in vivo studies (8.78 ± 1.06 kcal vs 7.70 ± 0.98 kcal, p = 0.033; 11.20 ± 1.13 kcal vs 8.49 ± 0.35 kcal, p = 0.001; respectively). The three dimensions of ablation zone had a tendency to be larger in the 15-G group than in the 17-G group in both studies. The ablation volume was larger in the 15-G group than in the 17-G group in both ex vivo and in vivo studies (29.61 ± 7.10 cm(3) vs 23.86 ± 3.82 cm(3), p = 0.015; 10.26 ± 2.28 cm(3) vs 7.79 ± 1.68 cm(3), p = 0.028; respectively). The circularity of ablation zone was not significantly different in both studies. The size of ablation zone was larger in the 15-G internally cooled electrode than in the 17-G electrode in both ex vivo and in vivo studies. Advances in Knowledge: Radiofrequency ablation of hepatic tumours using 15-G electrode is useful to create larger ablation zone.
    No preview · Article · Apr 2015 · The British journal of radiology
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    ABSTRACT: To evaluate the natural course of subcentimeter hypervascular nodules at high risk for developing into hepatocellular carcinomas (SHNHR) using serial magnetic resonance imaging (MRI) in patients with a history of hepatocellular carcinoma (HCC). An SHNHR was defined as a subcentimeter hypervascular nodule having typical imaging findings of HCC on gadoxetic acid-enhanced MRI and diffusion-weighted imaging. We included 39 patients with 46 SHNHRs (mean size ± standard deviation, 6.1 ± 1.6 mm; range, 3.2 - 9.0 mm). Overt HCC was defined as pathology proven HCC or a nodule larger than 1 cm with typical imaging findings of HCC. The cumulative rate and the independent predictive factors for progression to overt HCC were evaluated. The median follow-up period was 139 days (range, 64 - 392 days). The cumulative progression rate to overt HCC at 3, 6, 9, and 12 months was 13.9 %, 61.7 %, 83.2 %, and 89.9 %. The initial size of SHNHR was a significant predictor of progression to overt HCC, with an optimal cut-off value of 5.5 mm. The progression rate of SHNHR to overt HCC within 12 months was high (89.9 %) in patients with history of HCC. The initial size of SHNHR was an important predictor for progression to overt HCC. • Most SHNHRs (89.9 %) progressed to overt HCCs within 12 months. • Initial size was an important predictor for progression to overt HCCs. • The optimal cut-off value for initial nodule size was 5.5 mm.
    No preview · Article · Mar 2015 · European Radiology
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    ABSTRACT: Purpose: To compare radiofrequency (RF) ablation with nonanatomic resection (NAR) as first-line treatment in patients with a single Barcelona Clinic Liver Cancer (BCLC) stage 0 or A hepatocellular carcinoma (HCC) and to evaluate the long-term outcomes of both therapies. Materials and methods: This retrospective study was approved by the institutional review board. The requirement for informed consent was waived. Data were reviewed from 580 patients with HCCs measuring 3 cm or smaller (BCLC stage 0 or A) who underwent ultrasonographically (US) guided percutaneous RF ablation (n = 438) or NAR (n = 142) as a first-line treatment. Local tumor progression, intrahepatic distant recurrence, disease-free survival, and overall survival rates were analyzed by using propensity score matching to compare therapeutic efficacy. In addition, major complications and length of postoperative hospital stay were compared. Results: Before propensity score matching (n = 580), the 5-year cumulative rates of local tumor progression for RF ablation and NAR (20.9% vs 12.7%, respectively; P = .093) and overall survival rates (85.5% vs 90.9%, respectively; P = .194) were comparable, while the 5-year cumulative intrahepatic distant recurrence rates (62.7% vs 36.6%, respectively; P < .001) and disease-free survival rates (31.7% vs 61.1%, respectively; P < .001) in the NAR group were significantly better than those in the RF ablation group. After matching (n = 198), there were no significant differences in therapeutic outcomes between the RF ablation and NAR groups, including 5-year cumulative intrahepatic distant recurrence (47.0% vs 40.2%, respectively; P = .240) and disease-free survival rates (48.9% vs 54.4%, respectively; P = .201). RF ablation was superior to NAR for major complication rates and length of postoperative hospital stay (P < .001). Conclusion: In patients with one BCLC stage 0 or A (≤ 3 cm) HCC who received RF ablation or NAR as first-line treatment, there were no significant differences in long-term therapeutic outcomes; however, RF ablation was associated with fewer major complications and a shorter hospital stay after treatment.
    No preview · Article · Feb 2015 · Radiology
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    ABSTRACT: Objective: The purpose of this study was to investigate the value of enhancement kinetics and ancillary imaging findings on gadoxetic acid-enhanced and diffusion-weighted (DW) MR imaging for diagnosing hepatocellular carcinomas (HCCs) without the typical enhancement pattern on contrast-enhanced multiphasic MDCT in patients with chronic liver disease. Materials and methods: Eighty-two surgically confirmed HCCs without the typical enhancement pattern (hypervascular in the arterial phase, followed by washout on the portal or equilibrium phases) on triple-phase MDCT were enrolled in this study. The patients were classified into four categories based on the CT density pattern of arterial and equilibrium phases (isodense-isodense, hypodense-hypodense, isodense-hypodense, and hyperdense-isodense) compared to liver parenchyma. Signal intensity of HCCs on T2-weighted images (T2WI), arterial phase, 3 min late-phase, hepatobiliary phase (HBP) and DW images with a b value of 800 s/mm2 were qualitatively evaluated, and ADC values were measured. Fisher's exact test and Chi-square test were used to compare the frequency and trend of hyperintensity on T2WI, hypointensity on HBP images, hyperintensity on DW images, and histopathologic grades between groups with different CT density patterns. Kruskal-Wallis test was used to compare the ADC value between groups. Results: Thirty and 52 HCCs were categorized as hypervascular (hyperdense-isodense) and non-hypervascular HCCs (3, isodense-isodense; 37, hypodense-hypodense; 12, isodense-hypodense), respectively. Most HCCs showed hyperintensity on T2WI (77/82, 93.9%) and DW images (81/82, 98.8%) and hypointensity on HBP images (80/82, 97.6%). Thirty-eight HCCs (38/82, 46.3%) showed typical HCC enhancement pattern on dynamic MR images. There were no significant differences in the frequency and trend of signal intensity on T2WI, HBP images, DW images, and histopathologic grades with regard to the four CT density patterns (p<0.05). No significant difference in mean ADC values between groups was identified (p<0.05). Conclusion: Gadoxetic acid-enhanced and DW MR imaging can help diagnose HCCs with atypical enhancement patterns on multiphasic CT in patients with chronic liver disease.
    No preview · Article · Jan 2015 · European Journal of Radiology
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    ABSTRACT: Purpose: To compare the long-term outcomes of repeated hepatic resection and radiofrequency (RF) ablation for recurrent hepatocellular carcinoma (HCC) by using propensity score matching. Materials and methods: This retrospective study was approved by the institutional review board, and the requirement to obtain informed consent was waived. Thirty-nine patients who underwent repeated hepatic resection and 178 who underwent RF ablation for recurrent HCC (mean tumor size ± standard deviation, 1.8 cm ± 0.7) between November 1994 and December 2012 were included in the study. Patients ranged in age from 24 to 85 years (mean, 54.9 years). Men ranged in age from 25 to 85 years (mean, 54.8 years), and women ranged in age from 24 to 76 years (mean, 55.4 years). A 1:2 repeated hepatic resection group-RF ablation group matching was done by using propensity score matching. The overall survival (OS) and disease-free survival (DFS) were compared before and after propensity score matching. Complications were assessed. Results: Before matching, OS rates at 1, 3, 5, and 8 years were 88.8%, 88.8%, 83.9%, and 56.3%, respectively, with repeated hepatic resection and 98.9%, 82.5%, 71.0%, and 58.3% for RF ablation. DFS rates at 1, 3, and 5 years were 66.1%, 48.5%, and 43.1% for repeated hepatic resection and 70.1%, 40.8%, and 30.0% for RF ablation. After matching, the OS rates at 1, 3, 5, and 8 years were 98.7%, 85.7%, 72.1%, and 68.6%, respectively, and the DFS rates at 1, 3, and 5 years were 71.8%, 45.1%, and 39.4% in the RF ablation group (n = 78). Neither the OS nor DFS rate was significantly different between the two groups before matching (P = .686 and P = .461) and after matching (P = .834 and P = .960). The postoperative mortality rate was 2.6% in the repeated hepatic resection group and 0% in the RF ablation group. Conclusion: The long-term OS and DFS were not significantly different between repeated hepatic resection and RF ablation for patients with recurrent HCC after hepatic resection.
    No preview · Article · Jan 2015 · Radiology
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    ABSTRACT: To evaluate the feasibility of half-dose gadoxetic acid (0.0125mmol/kg) for liver MRI at 3-T compared to standard-dose (0.025mmol/kg) in patients at risk for nephrogenic systemic fibrosis (NSF). Forty patients who underwent both half-dose and standard-dose gadoxetic acid-enhanced MRIs were included. Contrast enhancement index (CEI) was calculated for liver, aorta, pancreas and kidney. Two observers independently rated and performed a one-to-one direct comparison of enhancement quality for both groups. Liver CEIs were not significantly different on arterial phase between the two groups but CEIs of standard-dose MRIs were greater than half-dose MRIs on other phases (P<0.001). CEIs were not significantly different on arterial phase for the aorta or on any phases for the pancreas. Kidney CEIs of standard-dose MRIs were greater than half-dose MRIs on all phases (P<0.05). Enhancement quality of both groups was diagnostic and did not significantly differ for any organs. In one-to-one direct comparisons of enhancement quality, equal ratings were given in 87.5% (35/40) of cases by observer 1 and 85.0% (34/40) by observer 2. Liver MRI using half-dose gadoxetic acid at 3-T can be a feasible alternative for standard-dose MRI in patients at risk for NSF. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
    No preview · Article · Dec 2014 · European Journal of Radiology
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    ABSTRACT: Objectives: The objective of this study was to compare the targeting and ablation performance between a newly developed radiofrequency (RF) electrode embedded with an electromagnetic position sensor (EMPS) at the electrode tip and a conventional RF electrode. Materials and methods: The institutional animal care and use committee approved this study. The targeting of paint balls within phantoms was performed under ultrasonography guidance by 2 radiologists (beginner vs expert) with an "in-plane" and "out-of-plane" approaches using the new RF electrode and a conventional RF electrode (n = 20 for each method). To evaluate the targeting performance, the electrode placement time and the number of electrode pullbacks for redirection were compared between the 2 electrodes. The ablation performance was also compared by analyzing the ablation volumes in ex vivo bovine and in vivo porcine livers (n = 30 and n = 24, respectively) and the cellular viability of the ablation zone in in vivo specimens. Results: In the phantom study, the RF electrode embedded with an EMPS showed a significantly shorter electrode placement time compared with the conventional RF electrode in both the in-plane and out-of-plane approaches by both radiologists (P < 0.05). The electrode pullback rate for both radiologists was lower in the new RF electrode than in the conventional RF electrode, but it did not reach statistical significance in the in-plane approach by the expert (P = 0.059). The ablation volumes analyzed with and without cellular viability in the ex vivo and in vivo studies were not significantly different between the 2 electrodes (P > 0.05). Conclusions: The RF electrode embedded with an EMPS is faster than the conventional electrode in the electrode placement into the target lesions. The ablation performance is not significantly different between the 2 electrodes.
    No preview · Article · Oct 2014 · Investigative Radiology
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    ABSTRACT: Objective: The purpose of this article is to evaluate the antiangiogenic effects of brivanib using dynamic contrast-enhanced MRI (DCE-MRI) in an orthotopic mouse model of human hepatocellular carcinoma (HCC). Materials and methods: With human HCC (HepG2 cell line) orthotopic nude mouse xenografts, brivanib was administered orally to the treatment group, and the vehicle was administered to the control group for 14 days. DCE-MRI was performed before the start of the therapy and 7 and 14 days after the start of therapy. Treatment-induced changes in tumor volume and microvessel density (MVD) assessed by CD31 immunohistochemistry were analyzed. Perfusion parameters, including volume transfer constant between blood plasma and extravascular extracellular space (K(trans)), fractional extravascular extracellular space per unit volume of tissue (ve), and rate constant between extravascular extracellular space and blood plasma (Kep), were calculated using the two-compartment model. Results: Brivanib shows potent antitumor activity in tumor volume. The mean (± SD) MVD of the tumors was statistically significantly lower in the brivanib-treated group (40.8 ± 17.3 vessels/field) than in the control group (55.2 ± 9.05 vessels/field) (p < 0.05). In the control group, the K(trans) value increased statistically significantly between the baseline and 14 days after treatment (p = 0.048). In the brivanib-treated group, the K(trans) and ve values decreased statistically significantly between baseline and 7 days after treatment (p = 0.024 and p = 0.031, respectively) and between baseline and 14 days after treatment (p = 0.043 and p = 0.018, respectively). The difference between the K(trans) and ve values between baseline and 14 days after treatment showed a statistically significant difference between the two groups (p = 0.004 and p = 0.034, respectively). Conclusion: DCE-MRI is feasible in the orthotopic mouse model of human HCC, and it can noninvasively monitor brivanib-induced changes in tumor microvasculature.
    No preview · Article · Jun 2014 · American Journal of Roentgenology
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    ABSTRACT: To determine the value of fusion imaging with contrast-enhanced ultrasonography (CEUS) and computed tomography (CT)/magnetic resonance (MR) images for percutaneous radiofrequency ablation (RFA) of very-early-stage hepatocellular carcinomas (HCCs) that are inconspicuous on fusion imaging with B-mode ultrasound (US) and CT/MR images. This retrospective study was approved by our institutional review board and the requirement for informed consent was waived. Fusion imaging with CEUS using Sonazoid contrast agent and CT/MR imaging was performed on HCCs (<2 cm) that were inconspicuous on fusion imaging with B-mode US. We evaluated the number of cases that became conspicuous on fusion imaging with CEUS. Percutaneous RFA was performed under the guidance of fusion imaging with CEUS. Technical success and major complication rates were assessed. In total, 30 patients with 30 HCCs (mean, 1.2 cm; range, 0.6-1.7 cm) were included, among which 25 (83.3%) became conspicuous on fusion imaging with CEUS at the time of the planning US and/or RFA procedure. Of those 25 HCCs, RFA was considered feasible for 23 (92.0%), which were thus treated. The technical success and major complication rates were 91.3% (21/23) and 4.3% (1/23), respectively. Fusion imaging with CEUS and CT/MR imaging is highly effective for percutaneous RFA of very-early-stage HCCs inconspicuous on fusion imaging with B-mode US and CT/MR imaging.
    Preview · Article · Mar 2014 · Clinical and molecular hepatology
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    ABSTRACT: To evaluate the feasibility of using coronary magnetic resonance angiography (CMRA) with stress-perfusion and delayed-enhancement MRI as a screening tool for the detection of coronary artery disease (CAD) in asymptomatic subjects. Three hundred and forty-one self-referred asymptomatic subjects were enrolled in this study. Cardiac MR imaging was performed using a 1.5-T scanner with a 32-channel cardiac coil. Coronary artery stenosis, regional wall motion abnormalities, myocardial perfusion abnormalities, and delayed myocardial enhancement were analyzed. The occurrence of new chest pain and cardiac events was assessed in 332 subjects (97.3 %) over an average 29 ± 6 months (range, 18-39 months) follow-up period. A total of 3296 (82.4 %) of 4000 coronary artery segments examined exhibited diagnostic image quality on combined whole-heart and volume-targeted CMRA. Combined MRI detected significant CADs in 13 (3.8 %) of 341 subjects. Among these, 11 subjects (84.6 %) had both coronary artery stenosis (≥50 % by diameter) on CMRA and stress-perfusion defects in corresponding areas. Five of the 13 subjects showed evidence of old myocardial infarctions on delayed-enhancement MRI. Three subjects (0.9 %) underwent percutaneous coronary intervention after CAD was detected on cardiac MRI. There were no cardiac events during the follow-up period in subjects who complied with follow-up. Normal stress-perfusion and delayed-enhancement MRI lead to excellent outcomes when used to predict future cardiac events in asymptomatic subjects. Coronary MRA correlates well with stress-perfusion MRI for detecting significant CAD and helps exclude CAD in asymptomatic individuals.
    Preview · Article · Jan 2014 · Journal of Cardiovascular Magnetic Resonance
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    ABSTRACT: To evaluate the incidence and causes of mistargeting after fusion imaging-guided percutaneous radiofrequency (RF) ablation of hepatocellular carcinomas (HCCs). Between September 2011 and March 2013, 955 HCCs in 732 patients were treated with percutaneous RF ablation. Among them, ablation of 551 HCCs was accomplished under fusion imaging guidance, and seven mistargetings were noted in seven patients (male-to-female ratio = 6:1; mean age, 60.1 y; range, 47-73 y). The incidence of mistargeting and the cause of liver disease in the patients with mistargeting were evaluated. The causes of mistargeting were assessed according to the following classification: small size of HCC, subcapsular location, subphrenic location, confusion with pseudolesions, poor conspicuity of HCC, poor sonographic window, and poor electrode path. The incidence of mistargeting after fusion imaging-guided RF ablation was 1.3% (7 of 551). All patients with mistargeting were hepatitis B virus carriers. The most common cause of mistargeting was the small size of HCC (100%; 7 of 7), followed by confusion with surrounding pseudolesions (85.7%; 6 of 7), subcapsular (71.4%; 5 of 7) and subphrenic locations (71.4%; 5 of 7), poor conspicuity of the HCC (71.4%; 6 of 7), poor sonographic window (28.6%; 2 of 7), and poor electrode path (28.6%; 2 of 7). The incidence of mistargeting after fusion imaging-guided RF ablation was 1.3%. The most common cause of mistargeting was the small size of HCC, followed by confusion with surrounding pseudolesions, subcapsular and subphrenic locations, and poor conspicuity of the HCC.
    No preview · Article · Dec 2013 · Journal of vascular and interventional radiology: JVIR
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    ABSTRACT: Hepatocyte specific contrast agents including gadoxetic acid and gadobenate dimeglumine are very useful to diagnose various benign and malignant focal hepatic lesions and even helpful to estimate hepatic functional reservoir. The far delayed phase image referred to as the hepatobiliary phase makes the sensitivity of detection for malignant focal hepatic lesions increased, but specificity of malignant diseases, including hepatocellular carcinoma, metastasis and cholangiocarcinoma, characterization remained to be undetermined.
    Full-text · Article · Dec 2013 · Clinical and molecular hepatology