Fatty-marrow transformation following radiotherapy for pancreatic cancer detected using dual-energy computed tomography: A case report.

Bone damage, a late side effect of radiotherapy, occurs concurrently with the replacement of fat cells in the bone marrow, causing changes in bone composition. Changes in composition can affect bone quality and disease states, and reduced bone mass can reduce quality of life by increasing the risk of fractures. A 70-year-old woman presented to the orthopedic outpatient clinic with the chief complaint of lower-back pain. The patient reported no history of trauma but was in great pain and had difficulty walking. Since the patient had a history of pancreatic cancer, tumor-marker testing, bone scintigraphy, and dual-energy computed tomography were performed. Although the tumor-marker levels were normal, dual-energy computed tomography and bone scintigraphy revealed fresh compression fractures of the L1 and L3 vertebrae. In addition, dual-energy computed tomography material-discrimination analysis suggested high fat density in the L2 vertebral body. The patient had received approximately 30 Gy radiation to the L2 vertebral body for her pancreatic cancer, which resulted in fatty myelination in the bone. The diagnosis of fatty myelination is made on T1-weighted magnetic resonance images; however, diagnosis remains challenging because of the difficulty in assessing bone morphology on magnetic resonance images. Moreover, some patients are not candidates for magnetic resonance imaging. Dual-energy computed tomography-based material-discrimination analysis can visually depict changes in the bone marrow, and is a valuable diagnostic tool owing to its simplicity.

Hysteroscopic resection with temporary balloon catheter occlusion of bilateral internal iliac arteries for managing retained products of conception after spontaneous abortion: Two cases report.

Retained products of conception (RPOC) is a condition in which trophoblastic tissue remains in the uterus after pregnancy, causing massive hemorrhage in some cases. Though RPOC is commonly treated by intrauterine curettage or hysteroscopic resection uterine artery embolization or hysterectomy may be performed in case of massive bleeding. We experienced two cases of RPOC after surgery for missed abortion that failed to respond to conservative treatment and required surgical treatment. They were treated by hysteroscopic resection with temporary balloon catheter occlusion of bilateral internal iliac arteries for fertility preservation. After the balloon catheters were inflated, the reduction of blood flow to RPOC was observed under transvaginal ultrasound. In both cases, good visualization was maintained throughout the surgery with minimal bleeding. They were discharged the next day and resumed menstruation 1 month after surgery. This paper demonstrates the usefulness of this procedure as a minimally invasive and fertility-preserving surgery.

Adrenocortical carcinoma with multiple liver metastases controlled by bland transarterial embolization and surgery resulting in long-term survival.

Adrenocortical carcinoma (ACC) is a rare malignant tumor with a poor prognosis. Local recurrence or distant metastases occur in more than 50% of cases. Patients with metastases have limited treatment options, and <15% have a 5-year survival time. Herein, we describe a 44-year-old woman with ACC and who underwent retroperitoneal tumor resection. Multiple liver and lung metastases were found 1-year postresection. Mitotane therapy started as systemic treatment. Lung metastases were controlled but liver metastases were progressive. The liver metastases were treated by performing 2 resections and 6 bland transarterial embolization (bland TAE), and are presently controlled with only 2 liver metastases of <20 mm. The present case showed that bland TAE can achieve long-term prevention of the progression of liver metastases of ACC. The ultraselective bland TAE for selective embolization supported by the latest computed tomography analysis techniques during arteriography could minimize liver damage caused by embolization and allowed multiple treatments which prolonged survival. We conclude that bland TAE can be effective for controlling liver metastases of ACC.

Potential of PALBI-T score as a prognostic model for hepatocellular carcinoma in alcoholic liver disease.

BACKGROUND AND AIM: With the control of viral hepatitis, alcoholic hepatocellular carcinoma (HCC) is becoming increasingly important in Japan. In alcoholic cirrhosis, the impact of portal hypertension is significant. Thus, it may be difficult to predict prognosis accurately with the reported prognostic scores. Here we propose the platelet-albumin-bilirubin tumor nodes metastasis (TNM) score (PALBI-T score) as a prognostic model for HCC in alcoholic liver disease, and investigate its usefulness. The PALBI-T score is an integrated score based on the TNM stage and PALBI grade including platelets, reflecting portal hypertension. METHODS: This study included 163 patients with alcoholic HCC treated at our Center from 1997 to 2018. We compared the prognostic prediction abilities of the Japan Integrated Staging (JIS) score, ALBI-T score, and PALBI-T score. The PALBI-T score was calculated similarly to the JIS and ALBI-T scores. Areas under the receiver operating characteristic curve (AUC) were calculated for predicting overall survival (OS). RESULTS: In predicting the 1-year survival, the JIS score had a larger AUC (AUC = 0.925) than the ALBI-T score (AUC = 0.895) and PALBI-T score (AUC = 0.891). On the other hand, there was no significant difference in predicting OS among the integrated scores. The PALBI-T score (AUC = 0.740) had the largest AUC, and the JIS score (AUC = 0.729) and ALBI-T score (AUC = 0.717) were not significantly different from the PALBI grade (AUC = 0.634). The PALBI grade reflected the degree of portal hypertension. CONCLUSION: In patients with alcoholic HCC, the Japan Integrated Staging score is useful for predicting short-term prognosis. The PALBI-T score, which reflects portal hypertension, appears to be a more valid prognostic score for predicting long-term prognosis.

Light Chain Deposition Disease Diagnosed Using Computed Tomography-Guided Kidney Biopsy.

Light chain deposition disease (LCDD) is characterized by the deposition of monoclonal immunoglobulin light chains in the kidney, which can cause end-stage kidney disease if not treated. While kidney biopsy is required for definitive diagnosis, choosing an appropriate biopsy method may be problematic when examining patients with atrophic kidneys. A 66-year-old Japanese man was referred to our institution with a three-month history of leg edema. Clinical investigations revealed proteinuria levels of 7.5 g/day. CT-guided percutaneous kidney biopsy was selected as the biopsy method because atrophic kidneys were poorly visualized on ultrasonography. Kidney biopsy revealed nodular glomerulosclerosis, exclusive deposition of the κ chain, and powdery electron-dense deposits, all of which were indicative of LCDD. Bence-Jones protein was detected in the urine. The patient also had an abnormal serum-free light chain ratio. Bone marrow biopsy revealed multiple myeloma; therefore, the patient was diagnosed to have LCDD with multiple myeloma. The patient was treated with daratumumab, bortezomib, cyclophosphamide, and dexamethasone. After a one-year follow-up, the patient had hematological and renal responses without any treatment-related adverse effects. Our case demonstrates the effectiveness of daratumumab as a treatment for LCDD with nephrotic-range proteinuria. Additionally, we suggest that CT-guided kidney biopsy should be considered as a diagnostic test in patients with kidney atrophy when making a definitive diagnosis.

High false-negative rate of the anterior spinal artery by intercostobronchial trunk arteriography alone compared to CT during arteriography.

OBJECTIVES: This study aimed to assess the frequencies of the anterior spinal arteries identified by CT during arteriography (CTA) and arteriography alone. METHODS: This retrospective study included 137 vessels in 83 patients who performed both bronchial arteriography and CTA and categorized them into three groups based on the catheter tip locations: intercostobronchial trunk (ICBT), bronchial artery (BA), and intercostal artery (ICA). The frequencies of anterior spinal artery identified by CTA and arteriography alone were compared for each group. RESULTS: ICBT, BA, and ICA groups were evaluated by CTA in 46, 79, and 12 vessels, respectively. By CTA evaluation, anterior spinal artery was identified in seven vessels (15.2%) in ICBT group, 0 in BA group and two (16.7%) in ICA group. The frequencies of anterior spinal artery were significantly higher (p < 0.05) in ICBT and ICA groups than in BA group. By arteriography evaluation alone, a faint anterior spinal artery was identified in two vessels (4.3%) in ICBT group, 0 in BA group, and 1 (8.3%) in ICA group. CONCLUSIONS: Anterior spinal artery branched only from the ICBT or ICA and not from the BA in both arteriography and CTA assessments. There was high false-negative rate (71%) of the anterior spinal artery by ICBT arteriography alone assessment compared to CTA assessment. This result explains one of the reasons that spinal ischemia occurs in arteriography-negative spinal artery cases. ADVANCES IN KNOWLEDGE: False-negative rate of anterior spinal artery was 71% (5/7) by intercostobronchial trunk arteriography alone assessment.

Gastric remnant reconstruction with left gastroepiploic artery supercharge after esophagectomy in a patient with an occluded right gastroepiploic artery: A technical and case report.

INTRODUCTION: Gastric remnant reconstruction is commonly used for esophagectomy reconstruction. However, standard reconstruction cannot be performed in some patients with a specific medical history. We report a case of esophagectomy and gastric remnant reconstruction with left gastroepiploic artery (LGEA) supercharge to treat esophageal cancer in a patient in whom the right gastroepiploic artery (RGEA) had previously been occluded. PRESENTATION OF CASE: A 65-year-old man underwent endoscopic submucosal dissection for thoracic esophageal squamous cell carcinoma. He was diagnosed with pathological T1b cancer with lymphatic invasion and a positive horizontal margin, and needed curative resection. He had previously undergone RGEA embolization to treat a pseudoaneurysm caused by chronic pancreatitis. We successfully performed esophagectomy and gastric remnant reconstruction with preoperative left gastric artery embolization and intraoperative LGEA supercharge. DISCUSSION: An absent RGEA blood supply is not always a contraindication for gastric remnant reconstruction when the collateral blood flows are well developed and supercharge can maintain the blood supply to the gastric remnant. CONCLUSIONS: Gastric remnant reconstruction with preoperative selective arterial embolization and intraoperative supercharge represents one of the options for high-risk patients with an altered gastric blood supply.

Quantitative analysis of gadoxetic acid-enhanced MRI for the differential diagnosis of focal liver lesions: Comparison between estimated intralesional gadoxetic acid retention by T1 mapping and conventional processing methods.

PURPOSE: To compare the estimated quantity of intratumor gadoxetic acid retention using T1 mapping of gadoxetic acid-enhanced magnetic resonance imaging (MRI) versus conventional processing methods for the differential diagnosis of focal liver lesions. METHODS: Seventy patients with hepatic lesions (colorectal metastasis (CRM) [n = 28], hepatocellular carcinoma (HCC) [n = 20], hemangioma [n = 12], and intrahepatic cholangiocarcinoma (ICC) [n = 10]) underwent gadoxetic acid-enhanced MRI, including pre- and post-contrast T1-weighted imaging and T1 mapping. Quantitative analyses included the lesion-to-liver signal intensity ratio (SIR) on hepatobiliary phase images, the pre- and post-contrast lesion T1 value difference (ΔT1 [ms]), and the lesion retention index (LRI [%]), which was the estimated intralesional gadoxetic acid retention calculated on pre- and post-contrast T1 maps using a two-compartment pharmacokinetic model. Results were compared between the four subcategories of focal liver lesions using the Kruskal-Wallis test, followed by the post-hoc Dunn's test and receiver operating characteristic (ROC) analysis to distinguish between pairs of the four lesion subcategories. RESULTS: This study identified significant differences in the LRI of the four lesion subcategories (p <  0.01), without significant differences in ΔT1 or SIR. Post-hoc analysis demonstrated significant differences in CRM vs. hemangioma (p <  0.01), hemangioma vs. ICC (p <  0.01), and HCC vs. ICC (p =  0.047) for the LRI. CONCLUSIONS: The quantity of intratumor gadoxetic acid retention estimated using pre- and post- contrast T1 mapping could distinguish focal liver lesions, unlike conventional processing methods, and captured unique lesion characteristics.

Which surgical procedure is effective for refractory chronic subdural hematoma? Analysis of our surgical procedures and literature review.

Refractory chronic subdural hematoma (CSDH) is rare but remains a difficulty for neurosurgeons, and no consensus on treatment procedures has been established. To discuss effective surgical procedures for refractory CSDH, we analyzed our surgical procedures and outcomes for refractory CSDH. We defined patients with refractory CSDH as those who presented with two or more recurrences. Fourteen patients with refractory CSDH were analyzed. Eight patients underwent burr-hole irrigation and closed-system drainage alone, four patients received embolization of the middle meningeal artery (MMA), and two patients with organized CSDH underwent large craniotomy with outer membranectomy as the third surgery. Two of the eight patients (25%) treated with burr-hole irrigation and drainage alone showed a third recurrence. No further recurrences were identified in patients treated with embolization of the MMA or craniotomy. However, statistical analysis showed no significant difference in cure rate between patients treated with burr-hole irrigation and drainage alone and patients treated with burr-hole irrigation and drainage with embolization of the MMA (P = .42). Similarly, no significant differences in cure rate were seen between patients treated with burr-hole irrigation and drainage alone and patients treated with craniotomy (P = .62). When selecting a surgical procedure, assessing whether the CSDH is organized is crucial. Embolization of the MMA may be considered as one of the optional treatments for refractory CSDH without organized hematoma. On the other hand, for refractory cases of organized CSDH, hematoma evacuation and outer membranectomy with large craniotomy or mini-craniotomy assisted by an endoscope may be suitable, as previous reports have recommended.

Magnetic Resonance Imaging Grading System for Preoperative Diagnosis of Leiomyomas and Uterine Smooth Muscle Tumors.

STUDY OBJECTIVE: To evaluate a new magnetic resonance imaging (MRI) grading system for preoperative differentiation between benign and variant-type uterine leiomyomas including smooth muscle tumors of uncertain malignant potential (STUMPs). DESIGN: Retrospective analysis (Canadian Task Force classification III). SETTING: Teaching hospital (Teine Keijinkai Hospital). PATIENTS: Three-hundred thirteen patient medical records were retrospectively reviewed if treated for uterine myomas and diagnosed with variant type leiomyomas or STUMPs (n = 27) or benign, typical leiomyomas (n = 286) and treated between January 2012 and December 2014. INTERVENTION: Uterine myoma classifications using MRI findings according to a 5-grade system (grades I-V) based on 3 elements. MEASUREMENTS AND MAIN RESULTS: Uterine myoma MRI classifications were based on 3 elements: T2-weighted imaging (high or low), diffusion-weighted imaging (high or low), and apparent diffusion coefficient values (high or low; apparent diffusion coefficient < 1.5 × 10-3 mm2/sec was considered low). Grades I to II were designated as typical or benign leiomyomas, grade III as degenerated leiomyomas, and grades IV to V as variant type leiomyomas or STUMPs. Accuracy levels were 98.9%, 100%, 94.3%, 58.8%, and 41.9% for grades I through V lesions, respectively. The grades were divided into 2 groups to discriminate benign leiomyomas and STUMPs (grades I-III were considered negative and grades IV-V positive). Grades IV to V scored 85.2% for sensitivity, 91.3% for specificity, 47.9% positive predictive value, 98.5% negative predictive value, a 9.745 positive likelihood ratio, and a .162 negative likelihood ratio. CONCLUSION: This novel MRI grading system for uterine myomas may be beneficial in differentiating benign leiomyomas from STUMPs or variant type leiomyomas and could be a future effective presurgical assessment tool.

Clinical Investigation of Refractory Chronic Subdural Hematoma: A Comparison of Clinical Factors Between Single and Repeated Recurrences.

BACKGROUND: Chronic subdural hematoma (CSDH) is sometimes refractory, and this is troublesome for neurosurgeons. Although many studies have reported risk factors or treatments in efforts to prevent recurrence, those have focused on single recurrence, and few cumulative data are available to analyze refractory CSDH. METHODS: We defined refractory CSDH as ≥2 recurrences, then analyzed and compared clinical factors between patients with single recurrence and those with refractory CSDH in a cohort study, to clarify whether patients with refractory CSDH experience different or more risk factors than patients with single recurrence, and whether burr-hole irrigation with closed-system drainage reduces refractory CSDH. RESULTS: Seventy-five patients had at least 1 recurrence, with single recurrence in 62 patients and ≥2 recurrences in 13 patients. In comparing clinical characteristics, patients with refractory CSDH were significantly younger (P = 0.04) and showed shorter interval to first recurrence (P < 0.001). Organized CSDH was also significantly associated with refractory CSDH (P = 0.02). Multivariate logistic regression analysis identified first recurrence interval <1 month (odds ratio, 6.66, P < 0.001) and age <71 years (odds ratio, 4.16, P < 0.001) as independent risk factors for refractory CSDH. On the other hand, burr-hole irrigation with closed-system drainage did not reduce refractory CSDH. CONCLUSIONS: When patients with risk factors for refractory CSDH experience recurrence, alternative surgical procedures may be considered as the second surgery, because burr-hole irrigation with closed-system drainage did not reduce refractory CSDH in our study.

A case of extrahepatic growth-type hepatocellular carcinoma presenting with bleeding from colonic metastasis.

A 60-year-old woman visited our hospital due to hematochezia. Colonoscopy revealed a 50-mm-diameter submucosal tumor with ulceration of the left side of the transverse colon, and magnetic resonance imaging (MRI) demonstrated the presence of small hepatic nodules. Submucosal tumor of the colon with liver metastasis was therefore diagnosed. To prevent tumor bleeding, we performed partial transverse colectomy. The histopathological diagnosis was moderately differentiated hepatocellular carcinoma presenting as a submucosal tumor with a high frequency of vascular invasion. Computed tomography (CT) angiography revealed a 40-mm-diameter confluent multinodular-type hepatocellular carcinoma with outward spread from segment II and multiple intrahepatic metastases. Our final diagnosis was hepatocellular carcinoma with hematogenous colon metastasis.

Transcatheter arterial embolization of hypervascular tumors with HepaSphere: prospective multicenter open label clinical trial of microspheres in Japan.

PURPOSE: To evaluate the feasibility and safety of transcatheter arterial embolization (TAE) with the use of HepaSphere microspheres for hypervascular tumors. MATERIALS AND METHODS: This was a prospective multicenter open label clinical trial involving six institutions in Japan. TAE was performed with the HepaSphere microspheres for hypervascular tumors in various locations. The endpoint of the study was the feasibility and safety of the procedure. The feasibility and safety were evaluated according to technical success and adverse events, respectively. Adverse events that were related to TAE were evaluated by using the Common Terminology Criteria for Adverse Events, version 4.0. RESULTS: Twenty-four patients were enrolled. The technical success rate was 100 % (24/24). Twenty-two (92 %) patients developed a total of 50 symptomatic adverse events, including 30 grade 1 events, 17 grade 2 events, and 3 grade 3 events. The most frequent adverse event was fever with an incidence of 63 %, followed by abdominal pain (25 %). CONCLUSION: TAE for hypervascular tumors with the HepaSphere microspheres was feasible and rarely caused major adverse events. TRIAL REGISTRATION: This trial was registered in JAPIC Clinical Trials Information (JapicCTI-111534).

Efficacy and long-term outcomes of radiofrequency ablation in the elderly with hepatocellular carcinoma.

AIM: The use of radiofrequency ablation (RFA) in elderly patients is increasing in those with hepatocellular carcinoma (HCC). This study compares the elderly (≥75 years old) to non-elderly patients (<75 years old) in the outcomes of the efficacy and safety of RFA. METHODS: Three hundred and thirty-five patients, 103 elderly and 232 non-elderly, with naive HCC who were treated with RFA from 1999 to 2012 were enrolled. Patient characteristics, complications, length of hospital stay, overall survival (OS), median survival time (MST), recurrence-free survival (RFS) and factors related to OS were analyzed. RESULTS: Median age was 79 years (range, 75-88) in the elderly group and 65 years (38-74) in the non-elderly group. The proportion of women (45.6% and 28.0%), hepatitis C virus infection (63.1% and 50.4%) and comorbidities (78.6% and 44.0%) in the elderly group compared to the non-elderly group, respectively, was significantly higher. No difference existed in the complications and length of hospital stay. The 5-year OS rates and MST were 67.3% and 90.5 months in the elderly group and 60.9% and 86.4 months in the non-elderly group, respectively (P = 0.486). The median RFS time was 20 months in the elderly group and 18.7 months in the non-elderly group (P = 0.429). In multivariate analysis, the Child-Pugh grade and tumor-node-metastasis stage were significantly associated with OS (P < 0.001, =0.003); age was not (P = 0.355). CONCLUSION: RFA in elderly patients is as effective and safe as in non-elderly patients for the treatment of HCC.

Correlation between surgical manipulations and the variation of surgeon's heart rate in brain surgery: technical note.

For improvement of surgical performance and safety, we record surgeries by video cameras. However, analysis of the video records is time consuming. To help this task, we are developing methods to automatically mark up significant time points in the surgery. As a possible mean for the marking, we focused on the surgeon's heart rate. During a craniotomy of an intracranial glioma, we recorded the surgeon's electrocardiogram using a telemeter and measured the R-to-R interval (RRI). We detected the stable state of heart rate as a peak-to-peak RRI of less than 5% of the mean of RRI data from 15 consecutive heartbeats. We also quantified the frequency of brain touches by the surgeon under the surgical microscope. We examined the association between the stability of surgeon's heart rate and the brain touches using a chi-square test. As the result, the stable state of surgeon's heart rate was associated with the brain touches (p < 0.05, odds ratio 5.1). We edited a one-minute digest video of the surgery based on only the heart rate data, and it was sufficient to understand how the surgery was preceded.

Implantable arterial port-related bloodstream infection in patients with primary or metastatic hepatic malignancies.

The incidence of implantable arterial post-related bloodstream infections (IAP-RBSI) among patients with unresectable hepatic malignancies is not well defined. We reviewed the 9-year incidence of implantable arterial post-related bloodstream infections in patients with hepatic malignancies, at a tertiary care center in Japan. The incidence was 1.9 infections per 10,000 catheter-days.

Feasibility of the virtual needle tracking system for percutaneous radiofrequency ablation of hepatocellular carcinoma.

AIM: To evaluate the feasibility of the real-time virtual needle tracking system for percutaneous radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC). METHODS: An electromagnetic field created by an ultrasound (US) machine detected the tracking bracket mounted onto the RFA needle. When the needle tip was confirmed to be in the accurate plane extracorporeally, the needle was inserted into the liver using the virtual navigation US system, and RFA was performed. Eight patients with eight liver lesions underwent percutaneous RFA under ultrasound for HCC from October to November 2012 using the real-time electromagnetic virtual needle tracking system (VirtuTRAX). RESULTS: The average size of the tumors was 11.5 mm with one lesion in S4, two in S5, two in S7 and three in S8. Sufficient margins were obtained in a single session in all cases. Using only B-mode, the needle tip was obscured due to the condition of the surrounding liver or subcutaneous fat tissue, but it was identifiable with the use of the virtual needle tracking device in all cases. In one case where the lesion was large, the needle was placed twice deliberately, but the second puncture was made difficult by the ablation artifact of the first puncture. With the tracking device, however, it was possible to perform the second puncture accurately. CONCLUSION: The virtual tracking system is useful in cases where the needle tip is obscured due to surrounding liver conditions or when multiple punctures are necessary due to the ablation artifact's obscuring the needle tip. Freehand puncturing may be possible in the future using this technique with further improvements in the system.

Pancreatic neuroendocrine neoplasm: correlation between computed tomography enhancement patterns and prognostic factors of surgical and endoscopic ultrasound-guided fine-needle aspiration biopsy specimens.

PURPOSE: To retrospectively determine whether enhancement patterns in the pancreatic and equilibrium phases of computed tomography (CT) for pancreatic neuroendocrine neoplasms are related to prognostic factors of surgical and endoscopic ultrasound-guided fine-needle aspiration biopsy specimens. METHODS: Twenty-five pancreatic neuroendocrine neoplasms in 22 patients underwent preoperative dynamic CT. Tumors were classified into two groups by enhancement patterns on preoperative CT. A washout pattern was defined as peak enhancement in the pancreatic phase with washout of at least 60 Hounsfield units in the equilibrium phase. Group 1 comprised tumors showing a washout pattern in more than half of tumor and Group 2 comprised tumors showing a washout pattern in less than half of the tumor. The Ki-67 index and the presence of vascular invasion were evaluated in surgical specimens. The Ki-67 index from biopsy specimens was compared with that from surgical specimens. RESULTS: There were 12 surgical specimens in Group 1 and 13 in Group 2. Group 2 showed significant correlations with larger Ki-67 indices (p < 0.05) and positive vascular invasion (p < 0.05). The Ki-67 index discrepancy between biopsy and surgical specimens of Group 2 was significantly greater than that of Group 1 (p < 0.05). CONCLUSIONS: Pancreatic neuroendocrine neoplasms in which less than half of the tumor showed a washout pattern were correlated with poor prognostic factors. Analysis of enhancement patterns may provide predictive information about whether endoscopic ultrasound-guided fine-needle aspiration biopsy is reliable for the assessment of Ki-67 index.

Feasibility of fused imaging for the evaluation of radiofrequency ablative margin for hepatocellular carcinoma.

AIM: To evaluate the feasibility of fusion of conventional imaging modalities to facilitate assessment of ablative margin of radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC). METHODS: Two hundred and thirty-nine liver lesions in 109 patients underwent percutaneous RFA under ultrasound for HCC from January 2008 to December 2010. Within these patients, 13 lesions in 12 patients who developed local tumor progression in the follow-up period of at least 8 months were retrospectively reviewed. Imaging obtained before and after RFA was used for creating fused images on a workstation. Ablative margins were assessed using only axial images, and with fused images. RESULTS: The ablative margin was assessed as sufficient in all 13 lesions using side-by-side axial images; however, all lesions were assessed as insufficient with fused imaging evaluation. The reason for the discrepancy of the assessment results were differences in the respiratory dislocation of the liver in the pre- and post-RFA images in eight lesions (61.5%), and rotational displacement of the liver and the torso in five (38.5%). The site of local tumor recurrence relative to the HCC lesion was craniocaudal in 12 lesions, dorsoventral in seven and lateral in seven. In all lesions, the site of local tumor recurrence was congruent with the area of the thinnest ablative margin. CONCLUSION: Assessment of ablative margin with fused imaging revealed insufficiency of ablation previously evaluated as sufficient with conventional axial imaging. Fused imaging evaluation has proved to be an accurate and useful tool for the assessment of RFA margins.