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We introduce two rare obstetric entities. They show very similar image findings, but the prognosis is different. Prognosis is generally favorable for complete hydatidiform mole with coexisting fetus (CHMCF), but placental mesenchymal dysplasia (PMD) has high fetal and neonatal mortality. Differential diagnosis is essential to management of pregnancy. Twin pregnancies with CHMCF are characterized by the coexistence of complete mole (diploid without fetal parts) and a normal live fetus with a normal placenta. US Findings: 1. Normal fetus and normal placenta with umbilical cord insertion 2. Separated molar placenta, vesicular sonographic pattern Differential Diagnosis: Partial mole (Triploid) Hematoma in placenta (normal β-hCG level) Placental mesenchymal dysplasia Biochemistry: β-hCG concentrations are extremely high • Chorionic villus sampling can be useful to differentiate in early pregnancy between CHMCF and partial hydatidiform mole • Amniocentesis or fetal blood sampling • Genotype of a CHM is entirely of paternal origin • Management of pregnancies with CHMCF has not been standardized • Continuation of CHMCF is an acceptable option: Intensive maternal follow up ultrasonography and β-hCG level monitoring • The chance of a live birth is 7 - 37%. • Complications: Fetal death, vaginal bleeding, preeclampsia, hyperthyroidism, gestational trophoblastic neoplasia Case 1: A 31-year old woman, gravida 2, para 0 CC: IUP at 17 weeks with abnormal placenta. Serum β-hCG levels: 234,358 mIU/mL (elevated) Fetal US: IUP at 17 weeks Twin pregnancy with complete H-mole and coexisting fetus Emergency Cesarian section for fetal distress at 27 wks Delivery: Boy, Apgar score 1'-1, 5'-1 Cytogenetic report: 46, XY, normal Pathological Diagnosis: Complete hydatidiform mole with coexisting fetus Case 2: A 32-year old woman, gravida 1, para 0 CC: IVF pregnancy follow up Serum β-hCG levels: 1,873,485 mIU/mL (elevated) Fetal US: IUP at 8 weeks Twin pregnancy with complete H-mole and coexisting fetus Dilatation and evacuation for vaginal bleeding at 10 weeks Pathological Diagnosis: Complete hydatidiform mole with coexisting fetus Part I: multiple fragments of placental tissue (about 5cc) with variable sized cysts (up to 0.7cm) Part II: multiple fragments of placental tissue (5 × 3cm) without grape like cystic change Developed persistent trophoblastic disease and 18 cycle chemotherapy Case 3: A 34-year old woman, gravida 1, para 0 CC: IVF pregnancy follow up fetus Serum β-hCG levels: 306,645 mIU/mL (elevated) Fetal US: IUP at 17 weeks Twin pregnancy with complete H-mole and coexisting fetus Rare placental lesion estimated to occur in 0.02% of pregnancies. Placental enlargement, dilated and tortuous chorionic vessels, and a focal distribution of cystically enlarged villi. US Findings: Typical large and thickened with multicystic, hypoechoic areas Differential Diagnosis: Partial mole, complete hydatidiform mole with coexisting fetus (CHMCF), chorangioma, intervillous hematoma, infarct or nonspecific hydropic changes • Characteristic morphologic features • Lack of trophoblastic hyperplasia –> maternal serum β-hCG levels are not elevated or only slightly elevated • No known risk of persistent gestational trophoblastic disease • No other specific maternal serum markers • Perinatal demise: not certain, but high as 43% • Cause of fetal death: Massive fetal hemorrhage secondary to rupture of delated periumbilical chorionic vessels Case 4: A 34-year old woman, gravida 1, para 0 CC: IUP at 12 weeks weeks Twin pregnancy with complete H-mole and coexisting fetus Serum β-hCG levels: 39,249 mIU/mL Fetal US: IUP at 12 weeks Twin pregnancy with complete H-mole and coexisting fetus Chorionic Villus Sampling (12 weeks) • Normal appearing placenta: 46, XX Normal • Abnormal appearing placenta: 46, XX Normal QF-PCR: placental mesenchymal dysplasia Pathological Diagnosis: Placental mesenchymal dysplasia Case 5: A 35-year old woman, gravida 2, para 1 CC: IUP 19 weeks, abnormal enlarged and honeycomb shaped placenta Serum β-hCG levels: none Fetal US: IUP at 20 weeks Twin pregnancy with complete H-mole and coexisting fetus R/O Placental mesenchymal dysplasia Amniocenthesis: Mosaicism 47,XY +15[3]/46,XX[31] Pathological Diagnosis: Placental mesenchymal dysplasia Complete Hydatidiform Mole with Coexisting Fetus vs Placental Mesenchymal Dysplasia We proposed two differential diagnosis points 1. Proportion of two patterns of placenta - CHMCF: similar size of two patterns of placenta - PMD: dominant vesicular pattern placenta 2. Umbilical cord insertion - CHMCF: center of normal placenta - PMD: junction of two different patterns of placenta → finally insert into abnormal placenta [ABSTRACT FROM AUTHOR]

Purpose: To assess factors affecting tumor visibility on planning ultrasound (US) for percutaneous radiofrequency (RF) ablation to treat small hepatocellular carcinomas (HCCs) primarily detected on computed tomography (CT) or magnetic resonance (MR) imaging. Materials and Methods: Patients referred for planning US for percutaneous RF ablation between September 2008 and June 2009 were prospectively enrolled from nine institutions in Korea. The first small (≤ 3 cm) single HCC or new single HCC after treatment was included. The study enrolled 898 patients (684 men and 214 women, age range 32-86 years). HCCs that were invisible on planning US were compared with visible HCCs with respect to tumor size, distance between the tumor and the diaphragm, subcapsular location, etiology of liver disease, liver cirrhosis, macronodular cirrhosis on US, ascites, Child-Pugh class, serum alpha fetoprotein (AFP) level, body mass index (BMI), previous treatments for HCC, previous chemoembolization treatments for HCC, institutions, and experience of radiologists. Results: Among 898 HCCs, 671 (74.7%) were visible on the planning US. In multivariate analysis, tumor size, distance between the tumor and the diaphragm, liver cirrhosis, and macronodular cirrhosis were statistically significant factors affecting US detection (each P < .05). Conclusions: Smaller tumors, subphrenic location of the tumor, liver cirrhosis, and macronodular cirrhosis were independent predictors of invisible tumors on planning US. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: The purpose of this study was to describe magnetic resonance (MR) findings of focal eosinophilic liver disease using gadoxetic acid (Gd-EOB-DTPA). Materials and Methods: Nineteen patients (M:F=14:5; age range, 26–66 years; mean age, 50 years) with 35 focal eosinophilic liver lesions were included after reviewing the medical records of 482 patients who underwent Gd-EOB-DTPA-enhanced MR imaging (MRI) on a 3.0-T unit between April 2008 and June 2009. The diagnosis of focal eosinophilic liver disease was established by means of percutaneous liver biopsy or surgery and consistent clinical findings. Two radiologists retrospectively reviewed MR images with consensus. Margin, shape and distribution of the lesions were analyzed. We also evaluated signal intensity of focal hepatic lesions on T 1- and T 2-weighted images and patterns of enhancement in dynamic contrast study. Results: The mean diameter of the lesions was 1.7 cm (range, 0.7–6.1 cm). Most of the focal eosinophilic liver lesions [n=31/35 (88.6%)] had poorly defined margins. They were usually isointense or slightly hypointense [n=34/35 (97.2%)] on T 1-weighted images and hyperintense [n=32/35 (91.4%)] on T 2-weighted images. Dynamic study showed enhancement (rim or homogeneous) on the arterial phase [n=21/35 (60%)] and hypointensity on the late venous phase [n=31/35 (88.6%)]. All the lesions were hypointense on the hepatobiliary phase images. Conclusion: Focal eosinophilic liver lesions tend to be hyperintense on the arterial phase and hypointense on the late venous phase during dynamic study of Gd-EOB-DTPA-enhanced MRI. Although these findings mimic other focal hepatic lesions, poorly defined margins of the lesions and peripheral eosinophilia might help distinguish focal eosinophilic liver disease from other hepatic lesions. [Copyright &y& Elsevier]

Abstract: Purpose: To compare the in vivo gastric injury observed during radiofrequency (RF) ablation of the liver abutting the stomach before and after the intragastric administration of chilled saline. Materials and methods: Twenty RF ablation zones were created in the livers of 10 pigs with a 1-cm-exposed active tip of an internally cooled electrode under ultrasound guidance for 10min. Ten RF ablation zones were created before (non-saline group) and after (saline group) the intragastric administration of approximately 1000mL of chilled saline, and 20 RF ablation zones were made in the posterior part of the left lobe abutting the stomach. The frequency and severity of the thermal injury observed in the stomach of the two groups were compared histologically. Results: All the resected gastric specimens showed thermal injuries of varying degrees of severity. The largest diameter of the gastric injury was significantly smaller in the saline group (mean 1.5cm; range 1.3–1.8cm) than in the non-saline group (mean 2.1cm; range 1.8–2.4cm) (p =0.000). The saline group showed significantly less thermal injury to the muscular layer of the gastric wall by the histopathology (p =0.033). Conclusions: The intragastric administration of chilled saline might be a useful technique for reducing the severity of gastric injury during RF ablation of the liver abutting the stomach. [Copyright &y& Elsevier]

Purpose: To evaluate the features of the Günther-Tulip filter (GTF) with or without tilting toward the anterior or posterior direction with use of phantom models and to describe our preliminary clinical experience to detect tilting and to reposition the GTF with regard to the maneuver's feasibility and usefulness. Materials and Methods: Two types of phantom models were made by inserting a GTF in a tube with or without tilting toward the anterior or posterior direction. Changes of the fluoroscopic features were observed in the postero-anterior projection. For the clinical trials, transjugular placement of the GTF in the inferior vena cava (IVC) was performed in 12 patients. As the result of the phantom study, repositioning of the filter was repeated until the four anchoring hooks stood on an imaginary line before releasing. Finally, cavograms were obtained and the angles were measured between the axis of the filter and the IVC axis and the coronal plane in the lateral projection. Results: In the phantom study, the four anchoring hooks stood in a transverse imaginary line when the filter without tilting was located at the center of the fluoroscopic projection. In the clinical trials, the mean number of repositionings was 1.67, and the mean angles between the axis of the filter and the IVC axis and the coronal plane in the lateral projection of the cavogram were 0.08 degrees +/- 2.32 and 0.18 degrees +/- 5.09, respectively. Conclusions: For placement of the Günther-Tulip filter, the maneuver to detect tilting and to reposition it was feasible and useful to prevent tilting seen after initial placement. [ABSTRACT FROM AUTHOR]

Objectives To determine the prognostic value of Gd-EOB-DTPA MRI findings of liver metastasis from breast cancer. Methods 29 metastatic lesions from 12 breast cancer patients who received chemotherapy were retrospectively reviewed. We evaluated hepatobiliary phase of the lesions and classified them as a “target” or “non-target” appearance. The relationship of appearance or SI ratio with tumor response was analyzed. Results A non-target appearance was more frequent in disease control group than in non-control group [14/18 (77.8%) vs. 4/18 (22.2%)], and it was associated with a better response [ p = 0.048]. Conclusion HBP analysis may be useful to predict the response to chemotherapy and survival. [ABSTRACT FROM AUTHOR]

The purpose of this work was to evaluate cases of benign ovarian mature teratoma (MT) with enhancing solid components on pelvic magnetic resonance imaging (MRI) and to correlate the MRI findings with the pathology reports. We retrospectively reviewed MRI findings and pathologic reports of 126 patients with pathologically confirmed ovarian MT. Enhancing solid components were observed in 24 (18.8%) of 128 benign MTs. The largest diameter ranged from 5.9 to 42.2 mm. The appearance was variable. Of 24 tumors, 19 (79.2%) had regular borders. On pathologic analysis, solid components of benign MTs were identified as glial tissue, thyroid tissue, fibrous stroma, or vessels. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: The purpose of the study was to determine significant imaging features to differentiate between infiltrative hepatocellular carcinoma (HCC) and confluent fibrosis (CF) in liver cirrhosis using Gd-EOB-DTPA-enhanced 3-T magnetic resonance imaging. Material and methods: Nineteen infiltrative HCCs and eight CFs were included. We evaluated the difference in imaging findings and apparent diffusion coefficient (ADC) between the two entities. We compared T2-weighted image (WI) and hepatobiliary phase (HBP) in terms of the clarity of the lesion outer margin. Results: Seventeen infiltrative HCCs showed lobulated margin, while focal CFs showed either straight (n =3) or irregular margins (n =5) (P =.001). All infiltrative HCCs had intact or bulging contours, and all focal CFs showed capsular retraction (P =.001). Fourteen infiltrative HCCs and two focal CFs showed arterial enhancement (P =.035). The ADC of infiltrative HCCs was significantly lower than that of CFs (P =.001). Satellite nodules were noted in 10 infiltrative HCCs. In terms of outer margin clarity, infiltrative HCCs showed a more distinct margin on HBP than on T2-WI (P =.005), while these two sequences were not significantly different in focal CFs (P =1.000). Conclusion: HBP improved the imaging characteristics of infiltrative HCC, allowing it to be distinguished from focal CF. Infiltrative HCC showed lower ADC values than focal CF. Lobular configuration, contour bulging, enhancement pattern, associated satellite nodules and portal vein thrombosis were still found to be highly suggestive MR findings for infiltrative HCC. [Copyright &y& Elsevier]

Abstract: Purpose: To determine specific imaging features of hepatic metastasis from colorectal cancer, focusing on the hepatobiliary phase (HBP) of gadoxetic acid-enhanced MRI. Materials and methods: Over a 2-year period, 79 hepatic metastatic lesions were identified from 32 patients (22 men and 10 women) who proven colorectal cancer and underwent gadoxetic acid-enhanced 3.0T MRI. Hepatic metastases were proven pathologically in 16 patients: by surgical liver resection (n =14) and by US-guided biopsy (n =2). The remaining 16 patients were considered to have hepatic metastasis based on imaging studies and clinical information. Two radiologists evaluated the imaging features of each MRI sequence, including high resolution T2WI, dynamic contrast enhancement study with hepatobiliary phase, and diffusion weighted image. We also compared SI of the lesions on T2WI and HBP. Results: T2WI showed homogeneous high SI (n =25; 31.7%), target appearance (n =3; 3.8%), reversed target appearance (n =2; 2.6%), and heterogeneously high SI (n =49; 62%). On HBP, homogeneous defect were seen in 22 lesions (27.9%), target appearance in five lesions (6.4%), reversed target appearance in two lesions (2.5%), and heterogeneous defect in 50 lesions (63.3%); including reticular (70%), partially globular (26%), and diffuse GGO-like (4%) patterns. According to the imaging features on HBP, the homogeneous defect and heterogeneous defect groups had a mean ADC value of 0.99×10−3 and 1.07×10−3 mm2/s, respectively, without statistically significant difference. Conclusion: Hepatic metastasis from colorectal cancer usually showed as a heterogeneous defect on HBP and a heterogeneous high SI on T2WI. The generally accepted “true defect” was not a common finding in hepatic metastasis from colorectal cancer. [Copyright &y& Elsevier]

Abstract: Purpose: The purpose was to describe magnetic resonance imaging (MRI) findings of breast cancer liver metastasis using gadoxetic acid (Gd-EOB-DTPA) with an emphasis on the added value of the hepatobiliary phase (HBP). Material and methods: Nine patients with 13 liver metastases were included in the study after the medical records of 29 breast cancer patients who underwent Gd-EOB-DTPA-enhanced MRI between February 2008 and June 2010 were reviewed. The diagnoses of liver metastasis were established by percutaneous liver biopsy or surgery and on the basis of image findings. Two radiologists retrospectively evaluated signal intensity (SI) and sizes of metastases and patterns of enhancement in an HBP. The SI ratio was calculated as the SI of the central hyperintense portion in “target” lesions divided by the SI of nearby normal liver parenchyma on the HBP. We also measured apparent diffusion coefficient (ADC) values from Diffusion Weighted Image (DWI). Results: Liver metastases were all hypointense [n=13/13 (100%)] on T1-weighted imaging (WI), and many lesions had a “target” appearance with a central high SI and a peripheral low SI rim (47%) on T2WI. Dynamic study showed rim enhancement on the arterial phase (85%) and a “target” appearance, consisting of a central enhancing portion with peripheral washout or hypointense rim, on the HBP (62%). The mean SI ratio was 0.7. The mean ADC value of “target” appearing metastases was 1.25 (×10−3 mm2/s; range 1.3–1.6) compared with a mean value of 0.8 (×10−3 mm2/s; range 0.8–1.4) in homogeneous defect on the HBP. There was statistically significant difference (P<.05). Conclusion: Breast cancer liver metastases commonly demonstrated as a peripheral ring enhancement on arterial dominant phase and a target sign with a central round enhancing portion and a peripheral hypointense rim on the HBP. [Copyright &y& Elsevier]

Abstract: Purpose: To validate the diagnostic performance of quadruple phase low tube voltage liver CT through the comparison with Gd-EOB-DTPA enhanced liver MRI for the detection of HCC. Materials and methods: Non-obese patients (38 men, eight women) with 68 HCCs underwent quadruple-phase CT at 16 MDCT (using low tube voltage, 80kVp; moderately high tube current, 280mAs) and Gd-EOB-DTPA-enhanced 3T MRI. Three observers independently and randomly reviewed the CT and MR images on a tumor-by-tumor basis. The diagnostic accuracy of these techniques for detecting HCC was assessed using alternative free-response receiver operating characteristic analysis. Sensitivity and positive predictive values were evaluated. The mean effective doses for the low dose CT were also evaluated. Results: The areas under the ROC curves were 0.963, 0.959, and 0.941 for low dose CT and 0.981, 0.982, and 0.976 for MRI. Differences in Az of the two techniques for each observer were not statistically significant (P >.05). Differences in sensitivity and positive predictive values between the two techniques for each observer were not also statistically significant: sensitivity (86.8%, 82.4%, 85.3% for CT and 95.6%, 94.1%, 91.2% for MRI) and positive predictive values (92.2%, 90.3%, 89.2% for CT and 92.9%, 92.8%, 92.5% for MRI). Six HCCs (8.8%) in five patients were observed only on hepatobiliary phase of MRI, and all were smaller than 1.5cm. The mean effective dose for CT was approximately 10.2mSv. Conclusions: Quadruple-phase low-dose liver CT (80kVp, 280mAs) had relatively good diagnostic performance for detecting HCC in non-obese patients. Because no significant difference was observed between low-dose CT and MRI, the use of low-dose liver CT can be justified based on its reduced radiation effects. [Copyright &y& Elsevier]

Abstract: Objective: To evaluate the value of the fade-out sign in the diagnosis of fatty liver (FL) on hepatic ultrasound (US). Methods: We evaluated 127 patients who underwent hepatic US, including 70 patients with FL and 57 normal control subjects. US images were qualitatively evaluated for the presence of the fade-out sign. This sign was considered present if there was a dark band on the deep portion of the liver on the harmonic image when compound sonography (CS) was converted to tissue harmonic CS mode. The degrees of FL were classified into mild, moderate, and severe. The distribution of lengths of dark bands in three groups was examined, and a multiple comparison of the average dark band length was carried out using one-way ANOVA. Results: The fade-out sign was seen in 55 of 70 FL patients (78.6%) compared to 3 of 57 control subjects (5.3%) (p <0.001). The sensitivity, specificity, accuracy, and positive predictive value of the fade-out sign for the US diagnosis of FL were 78%, 94%, 85.8%, and 94.8%, respectively. Among the 70 FL, there were 28 mild FL (mean length of dark band; 8.3mm±8.2), 31 moderate FL (mean; 28mm±6.3), and 11 severe FL (mean; 51mm±8.3). There were significant differences in band length according to severity (p <0.01). Conclusion: The fade-out sign on hepatic harmonic US was frequently present in FL. As fat infiltration increased, the fade-out sign lengthened. The fade-out sign offers a specific and new sign of FL. [Copyright &y& Elsevier]

Abstract: Purpose: To describe the paradoxical high signal intensity of hepatocellular carcinoma (HCC) in the hepatobiliary phase on gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI). Materials and Methods: A database search was performed to identify cases of HCC that showed unusual prolonged enhancement in the hepatobiliary phase of Gd-EOB-DTPA MRI. All patients received 3.0-T liver MRI including precontrast T1-weighted images, T2-weighted images and a post Gd-EOB-DTPA-enhanced dynamic study. The signal intensity of HCC was measured at pre-enhanced, arterial, portal, delayed and hepatobiliary phase using regions of interest. Radiologic and pathologic correlation was performed for the paradoxically prolonged enhancing portion of HCC in the hepatobiliary phase. Results: Four patients (all male, age range 44–70; mean 57.5 years) were included in this study. All patients showed HCC lesions that were low signal intensity (SI) on T1-WI, high SI on T2-WI, enhanced in arterial phase, and washed-out in delayed phase. All cases showed paradoxically high SI in hepatobiliary phase, which was unusual for HCC. Pathologically, they were all diagnosed as well-differentiated HCC with prominent cytoplasm and a bile secreting appearance. Conclusion: HCC may demonstrate the prolonged high signal intensity at the hepatobiliary phase on Gd-EOB-DTPA enhanced MRI. These HCCs tended to be highly differentiated and to have prominent bile secretion. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: To evaluate multidetector CT features of right intrahepatic portosystemic venous shunt (IPSVS). Materials and Methods: Pathways of right IPSVS were evaluated from 20 patients. Diameters of right portal veins were measured in IPSVS patients, 30 cirrhotic and 30 healthy patients. Result: Among 22 IPSVSs, shunt between posterior branch and inferior phrenic vein was most common. Diameters of the posterior branch were larger in IPSVS patients than in other groups. Conclusion: Most right IPSVSs drain to inferior phrenic vein through dilated posterior branch. [ABSTRACT FROM AUTHOR]

Purpose: To verify changes in the signal-to-noise ratios (SNRs) and contrast-to-noise ratios (CNRs) of hypervascular hepatocellular carcinomas (HCCs) on ferucarbotran-enhanced dynamic T1-weighted MR imaging.Materials and Methods: Fifty-two patients with 61 hypervascular HCCs underwent ferucarbotran-enhanced dynamic MR imaging, and then hepatic resection. Hypervascular HCCs were identified when definite enhancement was noted during the arterial dominant phase of three-phase MDCT. Dynamic MR Images with T1-weighted fast multiplanar spoiled gradient-recalled echo sequence (TR200/TE4.2) were obtained before and 20 s, and 1, 3, 5, and 10 min, after bolus injection of ferucarbotran. We estimated the signal intensities of tumors and livers, and calculated the SNRs and CNRs of the tumors.Results: On ferucarbotran-enhanced dynamic MR imaging, SNR measurements showed a fluctuating pattern, namely, an increase in SNR followed by a decrease and a subsequent increase (or a decrease in SNR followed by a increase and a subsequent decrease) in 50 (82.0%) of 61 tumors, a single-peak SNR pattern (highest SNR on 20 s, 1, 3, or 5 min delayed images followed by a decrease) in seven (11.5%), and a decrease in SNR followed by an increase in four (6.6%). Maximum absolute CNRs with positive value were noted on 10 min delayed images in 41 (67.2%) tumors, and maximum absolute CNRs with negative value were observed on 20 s delayed images in 12 (19.7%) and on 1 min delayed images in eight (13.1%).Conclusion: Despite showing various SNR and CNR changes, the majority of hypervascular HCCs demonstrated a fluctuating SNR pattern on ferucarbotran-enhanced dynamic MR imaging and a highest CNR on 10 min delayed image, which differed from the classic enhancement pattern on multiphasic CT. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To compare the diagnostic performance of a variety of magnetic resonance imaging (MRI) sequences, in order to identify the most effective ferucarbotran-enhanced sequence for the detection of multiple small hepatic VX2 carcinomas in rabbits. Methods: Fifteen rabbits with experimentally induced 135 VX2 carcinomas in the liver underwent ferucarbotran-enhanced MRI using the following nine pulse sequences: a fat-suppressed fast spin-echo (FSE) sequence with two echo times (TE) (proton density- and T2-weighted images), four different T2*-weighted fast multiplanar GRASS (gradient-recalled acquisition in the steady state) (FMPGR) with the combination of three TEs (9, 12, 15ms, respectively) and two flip angles (20°, 80°, respectively), T2*-weighted fast multiplanar spoiled GRASS (FMPSPGR), T1-weighted FMPSPGR, and dynamic T1-weighted FMPSPGR. All images were reviewed by three radiologists with quantitative and qualitative analysis. Results: Tumor-to-liver contrast-to-noise ratio of the proton density-weighted FSE sequence was significantly higher than those of the others (p <0.05). The lesion conspicuities of proton density- and T2-weighted FSE and T2*-weighted FMPGR (TE/flip angle, 9/20° and 12/20°) images were better and the image artifacts of T2*-weighted FMPGR (TE/flip angle, 15/20° and 12/80°) and T2*-weighted FMPSPGR images were more prominent than those of the others (p <0.05). The lesion detection in T2- and proton density-weighted FSE and T2*-weighted FMPGR (TE/flip angle, 12/20°) images were superior to those of the others and for the detection of very small hepatic tumors of less than 5mm, the sensitivities of these sequences were less than 30%. Conclusion: Ferucarbotran-enhanced T2- and proton density-weighted FSE and T2*-weighed FMPGR (TE/flip angle, 12/20°) images were found to be the most effective pulse sequences for the detection of multiple small hepatic VX2 carcinomas but these sequences were limited in the detection of very small hepatic tumors of less than 5mm in size. [Copyright &y& Elsevier]

Purpose: To assess the utility of contrast-enhanced agent detection imaging (ADI) in the assessment of the therapeutic response to percutaneous radiofrequency (RF) ablation in patients with hepatocellular carcinoma (HCC). Materials and Methods: Ninety patients with a total of 97 nodular HCCs (mean, 2.1+/-1.3 cm; range, 1.0-5.0 cm) treated with percutaneous RF ablation under the ultrasound guidance were evaluated with contrast-enhanced ADI after receiving an intravenous bolus injection of a microbubble contrast agent (SH U 508A). We obtained serial contrast-enhanced ADI images during the time period from 15 to 90 s after the initiation of the bolus contrast injection. All of the patients underwent a follow-up four-phase helical CT at 1 month after RF ablation, which was then repeated at 2-4 month intervals during a period of at least 12 months. The results of the contrast-enhanced ADI were compared with those of the follow-up CT in terms of the presence or absence of residual unablated tumor and local tumor progression in the treated lesions. Results: On contrast-enhanced ADI, technical success was obtained in 94 (97%) of the 97 HCCs, while residual unablated tumors were found in three HCCs (3%). Two of the three tumors that were suspicious (was not proven) for incomplete ablation were subjected to additional RF ablation. The remaining one enhancing lesion that was suspicious of a residual tumor on contrast-enhanced ADI was revealed to be reactive hyperemia at the 1-month follow-up CT. Therefore; the diagnostic concordance between the contrast-enhanced ADI and 1-month follow-up CT was 99%. Of the 94 ablated HCCs without residual tumors on both the contrast-enhanced ADI and 1-month follow-up CT after the initial RF ablation, five (5%) had CT findings of local tumor progression at a subsequent follow-up CT. Conclusion: Despite its limitations in predicting local tumor progression in the treated tumors, contrast-enhanced ADI is potentially useful for evaluating the early therapeutic effect of percutaneous RF ablation for HCCs. [ABSTRACT FROM AUTHOR]