Aortic and Internal Carotid Atherosclerosis in Patients with Carotid Stenosis: Semiautomatic Volumetric Analysis of Low-Attenuation Plaque on Curved Planar Reformations Using MDCT Angiographic Data.

This retrospective study included 65 patients who underwent multidetector computed tomography (MDCT) carotid angiography; 28 patients were <70 years old (group 1), and 37 were ≥70 years old (group 2). Each low-attenuation (<30 Hounsfield units [HU]) plaque volume (LPV) and total uncalcified plaque volume ([TUPV] ≤150 HU) were semiautomatically measured on each aortic arch and internal carotid artery (ICA) curved planar reformations (CPR), using MDCT angiographic data. Correlation coefficients were employed to assess the impact of each plaque volume on various factors including ICA stenosis. The correlations (r > 0.5) were observed between aortic LPV and each ICA stenosis ratio and >30% stenosis in group 1, between aortic TUPV and male gender in group 1, and between ICA-TUPV and each aortic TUPV or the largest plaque thickness in group 2. Marginal correlations were observed between hyperlipidemia and aortic LPV and ICA-TUPV in group 1. There was no association between cerebral infarction and the aortic and ICA plaques. Both the aortic arch and ICA plaque volumes can be measured clinically. The increasing aortic LPV may be a significant factor associated with the development of ICA stenosis in patients younger than 70 years old.

Impact of Isolated Cerebral Perfusion Technique for Aortic Arch Aneurysm Repair in Elderly Patients.

BACKGROUND: In aortic surgery, a severely atherosclerotic aorta is a known risk factor for perioperative stroke. The authors adopted a novel procedure of selective cerebral perfusion, named isolated cerebral perfusion (ICP), for the prevention of stroke during aortic arch operations. METHODS: Between January 2010 and June 2016, 48 patients (mean age, 80 ± 3 years) at Yokohama City University Medical Center, Yokohama, Japan underwent total aortic arch replacement, which included nine emergency cases with rupture. ICP was routinely performed for extracorporeal circulation during total arch replacement. The ICP procedure included the following steps: First, 9-mm Dacron grafts were anastomosed to the bilateral axillary arteries for systemic perfusion. Next, the left common carotid artery (LCCA) was clamped just before starting systemic perfusion. Dissection of the LCCA and insertion of a balloon-tipped cannula into the LCCA were performed. Extracorporeal circulation through the bilateral axillary arteries and selective cerebral perfusion to the LCCA were simultaneously started. Finally, at a bladder temperature of 25°C, clamping of the brachiocephalic and left subclavian arteries was performed. RESULTS: Preoperative evaluation by enhanced computed tomography confirmed that 62.2% of patients had severely atherosclerotic aortas and 37.8% had shaggy aortas. The overall 30-day mortality rate was 2.1%, whereas that for elective cases was 0%. Neurologic deficits developed in 3 patients (6.3%), 1 patient (2.6%) after an elective procedure. The 1-year and 3-year survival rates were 85.3% and 69.5% overall and 87.0% and 70.4% in elective cases, respectively. CONCLUSIONS: ICP during total aortic arch replacement presents an acceptable procedure for elderly patients with severely atherosclerotic aortas.

Semiautomatic Volumetry of Low Attenuation of Thoracic Aortic Plaques on Curved Planar Reformations Using MDCT Angiographic Data with 0.5 mm Collimation.

To evaluate the relationship of aortic low attenuation plaque volume (LAPV) on multidetector computed tomography (MDCT) with the abdominal aortic aneurysm (AAA), the coronary arterial disease (CAD, ≥50% stenosis), severe (≥90% stenosis) CAD, hypertension, and long-term (≥10 years) hypertension. Curved planar reformations (CPR) of three segments (the ascending, the arch, and the upper descending aorta) of the thoracic aorta were generated with attenuation-dependent color codes to measure LAPV with 0~29 HU and total noncalcified plaque volume (TNPV) with 0~150 HU in 95 patients. Correlation coefficients were employed to assess the impact of each LAPV and TNPV on AAA, CAD, severe CAD, hypertension, and long-term hypertension. Each Mean LAPV/cm and TNPV/cm was statistically greater in the aortic arch than the ascending (p < 0.001 on each) or the proximal descending segment (p < 0.001 on each). LAPV in the aortic arch has moderate correlations with AAA, severe CAD, and long-term hypertension (r = 0.643, 0.639, 0.662, resp.). Plaque volumes in each aortic segment can be measured clinically and the increasing LAPV in the arch may be a significant factor associated with the development of severe atherosclerosis underlying AAA, severe CAD, and long-term hypertension.

Efficacy of continuous versus intermittent subglottic secretion drainage in preventing ventilator-associated pneumonia in patients requiring mechanical ventilation: A single-center randomized controlled trial.

OBJECTIVE: Aspiration of subglottic secretion is a widely used intervention to prevent ventilator-associated pneumonia (VAP). This study aimed to compare the efficacy of continuous and intermittent subglottic secretion drainage (SSD) in preventing VAP. METHODS: A single-center randomized controlled trial was conducted on adult postoperative patients who were expected to undergo mechanical ventilation for more than 48 hours. Primary outcome measure was incidence of VAP and secondary outcome measures were length of mechanical ventilation and intensive-care unit (ICU) stay. RESULTS: Fifty-nine patients received continuous SSD, while 60 patients received intermittent SSD. Of these 119 patients, 88 (74%) were excluded and 15 and 16 patients were allocated to receive continuous and intermittent SSD, respectively. VAP was detected in 4 (26.7%) and 7 (43.8%) patients in the continuous and intermittent groups, respectively, (p=0.320). The length of mechanical ventilation was significantly shorter (p=0.034) in the continuous group (99.5±47.1 h) than in the intermittent group (159.9±94.5 h). The length of ICU stay was also shorter (p=0.0097) in the continuous group (6.3±2.1 days) than the intermittent group (9.8±4.8 days). CONCLUSIONS: Although continuous SSD did not reduce the incidence of VAP, it reduced the length of mechanical ventilation and ICU stay when compared to intermittent SSD.

Utility of multi-detector computed tomography scans after colorectal endoscopic submucosal dissection: a prospective study.

BACKGROUND AND AIMS: Several reports have described major adverse events after endoscopic submucosal dissection (ESD), such as perforation or bleeding. However, few studies have discussed the occurrence of post-ESD electrocoagulation syndrome (PEECS) after colorectal ESD. In addition, the occurrence of fever without abdominal pain in patients requires postoperative management similar to that required for PEECS. Therefore, we have defined post-ESD inflammatory syndrome (PEIS) composed of both PEECS and fever without abdominal pain. This study aimed to evaluate the correlation between the findings of multi-detector computed tomography (MDCT) imaging and PEIS in patients. METHODS: Between January 2015 and October 2015, we performed colorectal ESD in 100 patients; after this, all patients underwent abdominal examinations by MDCT scans. Nine patients who experienced intraoperative perforations or penetrations were excluded; 91 patients were enrolled in our prospective study. MDCT findings in patients were classified according to the amount of extraluminal gas. The patients were divided into 2 groups based on the presence or absence of extraluminal gas and were assessed for co-occurring PEIS. RESULTS: Among the 91 patients, extraluminal gas was observed in 31 (34%); of these, PEIS occurred in 14 (15%) patients. Patients with extraluminal gas had increased incidence of PEIS compared with patients without extraluminal gas (29% vs 8%, P = .014). CONCLUSIONS: Extraluminal gas was detected by MDCT in many cases and significantly correlated with the occurrence of PEIS, even in cases without obvious intraoperative perforation or penetration. MDCT findings after ESD may be useful for predicting PEIS and appropriate perioperative management.

A new device for fiducial registration of image-guided navigation system for liver RFA.

PURPOSE: Radiofrequency ablation for liver tumors (liver RFA) is widely performed under ultrasound guidance. However, discriminating between the tumor and the needle is often difficult because of cavitation caused by RFA-induced coagulation. An unclear ultrasound image can lead to complications and tumor residue. Therefore, image-guided navigation systems based on fiducial registration have been developed. Fiducial points are usually set on a patient's skin. But the use of internal fiducial points can improve the accuracy of navigation. In this study, a new device is introduced to use internal fiducial points using 2D US. METHODS: 3D Slicer as the navigation software, Polaris Vicra as the position sensor, and two target tumors in a 3D abdominal phantom as puncture targets were used. Also, a new device that makes it possible to obtain tracking coordinates in the body was invented. First, two-dimensional reslice images from the CT images using 3D Slicer were built. A virtual needle was displayed on the two-dimensional reslice image, reflecting the movement of the actual needle after fiducial registration. A phantom experiment using three sets of fiducial point configurations: one conventional case using only surface points, and two cases in which the center of the target tumor was selected as a fiducial point was performed. For each configuration, one surgeon punctured each target tumor ten times under guidance from the 3D Slicer display. Finally, a statistical analysis examining the puncture error was performed. RESULTS: The puncture error for each target tumor decreased significantly when the center of the target tumor was included as one of the fiducial points, compared with when only surface points were used. CONCLUSION: This study introduces a new device to use internal fiducial points and suggests that the accuracy of image-guided navigation systems for liver RFA can be improved by using the new device.

Prediction of Time to Castration-Resistant Prostate Cancer Using Bone Scan Index in Men with Metastatic Hormone-Sensitive Prostate Cancer.

INTRODUCTION: We evaluated bone scan index (BSI) as a predictive biomarker for time to castration-resistant prostate cancer (CRPC) in patients with metastatic hormone-sensitive prostate cancer (mHSPC). MATERIALS AND METHODS: We identified 85 consecutive mHSPC patients treated with first-line androgen deprivation therapy. We analyzed the correlations between time to CRPC and clinicopathological characteristics, including age, prostate-specific antigen (PSA) level, Gleason score, clinical TNM stage, hemoglobin, lactate dehydrogenase, C-reactive protein, and BSI. RESULTS: The median BSI was 2.7%. Progression to CRPC occurred in 55 (64.7%) patients and the median time to CRPC was 12.9 months. In multivariate analysis, 3 significant risk factors for time to CRPC were identified: age (>73 vs. ≤73 years; hazard ratio [HR] 0.53), p = 0.038, PSA level (>270 vs. ≤270 ng/mL; HR 0.53, p = 0.038), and BSI (>2.7 vs. ≤2.7%; HR 2.97, p < 0.001). CONCLUSION: Age, PSA level, and BSI were found to be significant predictive factors for time to CRPC in patients with mHSPC.

Emergent Uterine Arterial Embolization Using N-Butyl Cyanoacrylate in Postpartum Hemorrhage with Disseminated Intravascular Coagulation.

Although it is widely accepted that uterine artery embolization (UAE) is an effective therapeutic strategy for postpartum hemorrhage (PPH), no consensus has been reached regarding the efficacy of UAE in patients with PPH with disseminated intravascular coagulation (DIC). This single-center retrospective cohort study included patients treated with UAE using NBCA for PPH between 2010 and 2015. The patients were divided into DIC and non-DIC groups, according to the obstetrical DIC score and the overt DIC diagnostic criteria issued by the International Society of Thrombosis and Haemostasis (ISTH), and their clinical outcomes were compared. There were 28 patients treated with UAE using NBCA. Complete hemostasis was achieved by UAE in 19 of 28 patients. In eight of nine patients with unsuccessful hemostasis, surgical hemostatic interventions were performed after UAE, and hemostasis was achieved in seven patients. UAE using NBCA showed no significant intergroup differences in complete hemostasis according to the presence or absence of DIC based on obstetrical DIC score (70% versus 62.5%, P = 1.000) or ISTH DIC score (54.5% versus 76.5%, P = 0.409). UAE using NBCA may be a useful first-choice treatment for PPH with DIC.

Prognostic Value of Automated Bone Scan Index in Men With Metastatic Castration-resistant Prostate Cancer Treated With Enzalutamide or Abiraterone Acetate.

PURPOSE: Bone scan index (BSI) is an objective tool for quantifying bone metastasis load. We assessed its prognostic usefulness in patients with metastatic castration-resistant prostate cancer (CRPC) treated with enzalutamide (ENZ) or abiraterone acetate (AA). MATERIALS AND METHODS: We analyzed 40 patients who received ENZ or AA treatment (ENZ/AA) for metastatic CRPC. The Cox proportional hazards model and a C-index were used to investigate associations between overall survival (OS) and BSI, and patient age, prostate-specific antigen, time to CRPC, previous docetaxel use, and pain. RESULTS: Median OS after ENZ/AA was 17.8 months. All patient deaths (n = 19; 47.5%) were from prostate cancer. In multivariate analysis, decreased BSI was an independent predictor for longer OS (hazard ratio, 8.97; P = .011). Inclusion of BSI improved the C-index from 0.721 to 0.792 in predicting OS after ENZ/AA. CONCLUSIONS: Decreased BSI after ENZ/AA independently predicts longer OS.

Central vascular structures as a characteristic finding of regenerative nodules using hepatobiliary phase gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid-enhanced MRI and arterial dominant phase contrast-enhanced US.

OBJECTIVE: We investigated the characteristic findings of regenerative nodules (RNs) for differentiating early hepatocellular carcinoma (HCC) from high-grade dysplastic nodules (HGDNs) using magnetic resonance imaging (MRI) with gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid (Gd-EOB-DTPA; EOB-MRI) and contrast-enhanced ultrasonography (CEUS) in patients with chronic liver disease. SUBJECTS AND METHODS: Pathologically confirmed lesions (100 early HCCs, 7 HGDNs, and 20 RNs with a maximum diameter of more than 1 cm and mean maximal diameters of 15.5, 15.1, and 14.8 mm, respectively) were enrolled in this retrospective study. The signal intensities of these lesions during the hepatobiliary phase of EOB-MRI were investigated, and findings characteristic of RNs using this modality were also evaluated using CEUS. RESULTS: Ninety-eight of the 100 early HCCs that were hypo-intense (n = 95), iso-intense (n = 2), or hyper-intense (n = 1) and the seven HGDNs that were hypo-intense (n = 6) or hyper-intense (n = 1) during the hepatobiliary phase of EOB-MRI exhibited centripetal vessels during the arterial dominant phase of CEUS, although one early HCC that was hypo-intense exhibited both centrifugal and centripetal vessels. Eighteen of the 20 RNs and one early HCC that were hyper-intense with a small central hypo-intensity and the remaining two RNs that were hyper-intense on EOB-MRI exhibited centrifugal vessels during the arterial dominant phase of CEUS. The small central hypo-intense area corresponded to central vascular structures in the lesion, such as the hepatic artery and portal vein running from the center to the periphery, when viewed using CEUS. CONCLUSION: Central vascular structures may be a characteristic finding of RNs when observed during the hepatobiliary phase of EOB-MRI and the arterial dominant phase of CEUS.

Effect of transarterial embolization for post-partum hemorrhage on subsequent pregnancy.

Although pregnancy after transarterial embolization (TAE) has occasionally been reported, gelatin sponge was used as the embolic agent in most of these cases. Reports on the effect of TAE with permanent embolic agents such as N-butyl cyanoacrylate or coil on subsequent pregnancies are rare. We describe placenta accreta associated with difficult hemostasis in two patients who became pregnant after TAE with permanent embolic agents. In pregnancy after TAE with permanent embolic agents, placenta accreta occurs frequently and well-developed collateral vessels are highly likely, resulting in difficult hemostasis. Although the acceptability of pregnancy after TAE with permanent embolic agents is controversial, patients should be informed that pregnancy is extremely high risk.

Prognostic value of a computer-aided diagnosis system involving bone scans among men treated with docetaxel for metastatic castration-resistant prostate cancer.

BACKGROUND: The bone scan index (BSI), which is obtained using a computer-aided bone scan evaluation system, is anticipated to become an objective and quantitative clinical tool for evaluating bone metastases in prostate cancer. Here, we assessed the usefulness of the BSI as a prognostic factor in patients with metastatic castration-resistant prostate cancer (mCRPC) treated using docetaxel. METHODS: We analyzed 41 patients who received docetaxel for mCRPC. The Bonenavi system was used as the calculation program for the BSI. The utility of the BSI as a predictor of overall survival (OS) after docetaxel was evaluated. The Cox proportional hazards model was used to investigate the association between clinical variables obtained at docetaxel treatment, namely PSA, patient age, liver metastasis, local therapy, hemoglobin (Hb), lactase dehydrogenase (LDH), albumin (Alb), PSA doubling time, and BSI and OS. RESULTS: The median OS after docetaxel therapy was 17.7 months. Death occurred in 22 (53.7%) patients; all deaths were caused by prostate cancer. In multivariate analysis, three factors were identified as significant independent prognostic biomarkers for OS after docetaxel; these were liver metastases (yes vs no; HR, 3.681; p = 0.026), Alb (<3.9 vs ≥ 3.9; HR, 3.776; p = 0.020), and BSI (>1% vs ≤ 1%; HR, 3.356; p = 0.037). We evaluated the discriminatory ability of our models including or excluding the BSI by quantifying the c-index. The BSI improved the c-index from 0.758 to 0.769 for OS after docetaxel. CRPC patients with a BSI >1 had a significantly shorter OS than patients with a BSI ≤ 1 (p = 0.029). CONCLUSIONS: The BSI, liver metastases and Alb were independent prognostic factors for OS after docetaxel. The BSI might be a useful tool for risk stratification of mCRPC patients undergoing docetaxel treatment.

Prognostic value of the bone scan index using a computer-aided diagnosis system for bone scans in hormone-naive prostate cancer patients with bone metastases.

BACKGROUND: The bone scan index (BSI) using a computer-aided diagnosis system for bone scans is expected to be an objective and quantitative clinical tool for evaluating bone metastatic prostate cancer. This study aimed to evaluate the pretreatment BSI as a prognostic factor in hormone-naive prostate cancer patients with bone metastases. METHODS: The study included 60 patients with hormone-naive, bone metastatic prostate cancer that was initially treated with combined androgen blockade therapy. The BONENAVI system was used for calculating the BSI. We evaluated the correlation between overall survival (OS) and pretreatment clinicopathological characteristics, including patients' age, initial prostate-specific antigen (PSA) value, Gleason scores, clinical TNM stage, and the BSI. Cox proportional hazards regression models were used for statistical analysis. RESULTS: The median follow-up duration was 21.4 months. Clinical or PSA progression occurred in 37 (61.7%) patients and 18 (30.0%) received docetaxel. Death occurred in 16 (26.7%) patients. Of these deaths, 15 (25.0%) were due to prostate cancer. The median OS was not reached. In multivariate analysis, age and the BSI were independent prognostic factors for OS. We evaluated the discriminatory ability of our models, including or excluding BSI by quantifying the C-index. The BSI improved the C-index from 0.751 to 0.801 for OS. Median OS was not reached in patients with a BSI ≤ 1.9 and median OS was 34.8 months in patients with a BSI >1.9 (p = 0.039). CONCLUSIONS: The pretreatment BSI and patients' age are independent prognostic factors for patients with hormone-naive, bone metastatic prostate cancer.

Use of vessel patterns on contrast-enhanced ultrasonography using a perflubutane-based contrast agent for the differential diagnosis of regenerative nodules from early hepatocellular carcinoma or high-grade dysplastic nodules in patients with chronic liver disease.

OBJECTIVE: We evaluated the use of tumor vessel patterns observed during arterial-phase contrast-enhanced ultrasonography (US) to differentiate regenerative nodules (RN) from early hepatocellular carcinoma (HCC) or high-grade dysplastic nodules (HGDN) in patients with chronic liver disease. SUBJECTS AND METHODS: Pathologically confirmed lesions (83 early HCC, 6 HGDN, and 13 RN with mean maximal diameters of 15.4, 15.3, and 16.2 mm, respectively) were enrolled in this retrospective study. We performed contrast-enhanced US using a perflubutane-based contrast agent. We then classified the tumor vessels observed during the arterial phase of contrast-enhanced US into two patterns: peripheral vessels (centripetal pattern) and central vessels (centrifugal pattern). RESULTS: Eighty-one (97.6%) of the 83 early HCC exhibited various enhancement patterns (hypovascular, 44.6%; isovascular, 25.3%; and hypervascular, 27.7%) and a peripheral vessel pattern, while the remaining 2 lesions (2.4%) exhibited hypovascular enhancement and a central vessel pattern. All 6 HGDN lesions were hypovascular with a peripheral vessel pattern. Twelve (92.3%) of the 13 RN were hypovascular with a central vessel pattern, and the remaining one (7.7%) was hypervascular with a central vessel pattern. When lesions exhibiting a central vessel pattern during arterial-phase contrast-enhanced US were diagnosed as RN, the sensitivity, specificity, and accuracy of these diagnoses were 100%, 97.8%, and 98.0%, respectively. CONCLUSION: The tumor vessel patterns observed during arterial-phase contrast-enhanced US may be useful for differentiating RN from early HCC or HGDN in patients with chronic liver disease.

Renal perfusional cortex volume for arterial input function measured by semiautomatic segmentation technique using MDCT angiographic data with 0.5-mm collimation.

OBJECTIVE: The purpose of this study was to evaluate the usefulness of renal perfusional cortex volume for arterial input function. MATERIALS AND METHODS: This retrospective study included 45 potential kidney donors--33 patients with aortic dissection and 12 patients with renovascular hypertension--who underwent both MDCT angiography with 0.5-mm collimation and renal (99m)Tc-diethylenetriamine pentaacetic acid (DTPA) scanning using the modified Gates method. Each perfusional cortex volume for the arterial input function and parenchymal volume was measured by semiautomatic segmentation using the region-growing technique. Linear regression analysis and correlation coefficients were used to assess the impact of the cortical volume, parenchymal volume, and renal scanning glomerular filtration rate (GFR) on estimated GFR (eGFR) using a modified Modification of Diet in Renal Disease (MDRD) equation. RESULTS: The correlation coefficient was higher for the total renal DTPA GFR adjusted for body surface area, weight-adjusted perfusion cortex volume, and adjusted total parenchyma volume in rank (r = 0.712, 0.642, 0.510, respectively, p< 0.0001 for each). The coefficient of the right renal perfusional cortex volume percent with a mean value of 52.1% ± 10.1% was 0.826 (p < 0.0001) for the right renal DTPA GFR percent with a mean value of 51.0% ± 12.1% (range, 22.0-89.5%), although the value for the right renal parenchymal volume percent with a mean value of 49.5% ± 5.5% was 0.764 (p < 0.0001). CONCLUSION: Weight-adjusted perfusional cortex volume for arterial input function can be measured clinically and may replace renal DTPA scanning using the modified Gates method.

Quantitative analysis of vascular signs on early postmortem multi-detector computed tomography.

PURPOSE: To clarify the postmortem multi-detector computed tomography (MDCT) vascular signs that occur shortly after death. MATERIALS AND METHODS: The vascular signs in MDCT images were evaluated quantitatively in 96 early postmortem cardiac arrest patients, 47 cardiac arrest patients who survived due to resuscitation and 47 control patients without cardiac arrest. RESULTS: Elliptical (40 cases) or collapsed deformity (2 cases, in only the abdominal aorta) and high-attenuated sedimentation (19 cases in the aorta and 10 cases in superior or inferior vena cava) were limited to the postmortem patients. The incidence of elliptical deformity was higher for the abdominal aorta, descending thoracic aorta and ascending thoracic aorta in rank. The sedimentation was observed in the ascending thoracic aorta with a higher frequency than in the descending thoracic and abdominal aorta. A high-attenuating wall in any portion of the aorta was observed in 34 of the postmortem patients, 11 of the surviving patients and 10 of the control group, with a predominance of the ascending thoracic aorta. CONCLUSION: Elliptical deformity in the abdominal and descending thoracic aorta and high-attenuated sedimentation in the ascending thoracic aorta were shown to be signs of postmortem MDCT shortly after death.

Contrast-enhanced ultrasonography findings using a perflubutane-based contrast agent in patients with early hepatocellular carcinoma.

OBJECTIVE: We evaluated the contrast-enhanced ultrasonography (US) imaging features of early hepatocellular carcinomas (HCCs) and compared these findings with those obtained using contrast-enhanced computed tomography (CT). SUBJECTS AND METHODS: Forty-three patients with 52 early HCCs with a mean maximal diameter of 15.6mm were enrolled in this retrospective study. After confirming the location of the target lesion using fusion imaging combining conventional US and hepatobiliary phase of contrast-enhanced magnetic resonance (MR) imaging with gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid, we evaluated findings of contrast-enhanced US using a perflubutane-based contrast agent. The contrast-enhanced US detection rates for hyper-vascularity in early HCCs were compared with those obtained for contrast-enhanced CT. RESULTS: Transient hypo-vascularity subsequent to iso-vascularity during arterial phase and iso-vascularity during portal and post-vascular phases were the predominant contrast-enhanced US findings seen for 25 (48.1%) of the 52 early HCCs. Nine (17.3%) showed iso-vascularity during all three phases, while 1 (1.9%) showed hypo-vascularity during all three phases. The remaining 17 (32.7%) showed partial or whole hyper-vascularity during arterial phase, iso-vascularity during portal phase, and iso- or hypo-vascularity during post-vascular phase. The detection rate for the hyper-vascularity of early HCCs using contrast-enhanced US (32.7%, 17/52) was significantly higher than that obtained using contrast-enhanced CT (21.2%, 11/52) (P<0.05 by McNemar test). CONCLUSION: Hypo-vascularity, iso-vascularity, and hyper-vascularity were observed during the arterial phase of contrast-enhanced US in 50.0%, 17.3%, and 32.7% of the early HCCs, respectively. Contrast-enhanced US was more sensitive than contrast-enhanced CT for the detection of hyper-vascularity in early HCCs. Of note, early HCCs might not exhibit the early arterial enhancement that is generally considered to be a typical finding for HCCs.

Use of contrast-enhanced ultrasonography with a perflubutane-based contrast agent performed one day after transarterial chemoembolization for the early assessment of residual viable hepatocellular carcinoma.

OBJECTIVE: We evaluated the efficacy of contrast-enhanced ultrasonography (US), compared with contrast-enhanced computed tomography (CT), for early assessments after transarterial chemoembolization (TACE) for the treatment of hypervascular hepatocellular carcinoma (HCC) lesions. SUBJECTS AND METHODS: Thirty-two patients with 59 HCC lesions who were scheduled to receive TACE were enrolled in this prospective study. TACE was performed by injecting a mixture of iodized oil and miriplatin hydrate, followed by a gelatin sponge. Digital subtraction angiography (DSA) and/or contrast-enhanced CT were performed 2-6 months after TACE and were used as the reference standard for residual HCC; the detection rates for residual viable HCC using contrast-enhanced US with a perflubutane-based contrast agent and a high mechanical index (MI) mode performed one day after TACE were also compared with those obtained using contrast-enhanced CT performed one month after TACE. The comparisons were made using the McNemar test. RESULTS: Forty-seven (79.7%) of the 59 HCC lesions were diagnosed as having residual viability based on DSA and contrast-enhanced CT findings obtained 2-6 months after TACE. Eight (17.0%) of the 47 HCC lesions that were diagnosed as having residual viability using one-day contrast-enhanced US were not detected using one-month contrast-enhanced CT because of artifacts produced by the high attenuation of the iodized oil. The detection rate for residual HCC lesions using one-day contrast-enhanced US (95.7%, 45/47) was significantly higher than that using one-month contrast-enhanced CT (78.7%, 37/47) (P<0.05). CONCLUSION: Contrast-enhanced US performed one day after TACE is more sensitive than contrast-enhanced CT performed one month after TACE for detecting residual viable HCC.

Use of fusion imaging combining contrast-enhanced ultrasonography with a perflubutane-based contrast agent and contrast-enhanced computed tomography for the evaluation of percutaneous radiofrequency ablation of hypervascular hepatocellular carcinoma.

OBJECTIVE: We evaluated the efficacy of fusion imaging, which fuses contrast-enhanced ultrasonography images with arterial-phase, contrast-enhanced CT images as a reference on a single screen in real time, for the evaluation of the effectiveness of radiofrequency ablation for treatment of hypervascular hepatocellular carcinoma. MATERIALS AND METHODS: Eighty hepatocellular carcinoma lesions with a maximum diameter of between 1 and 3 cm that were scheduled for treatment with radiofrequency ablation were enrolled in this prospective study. After bolus injection of perflubutane-based contrast agent, fusion imaging combining contrast-enhanced ultrasonography images and arterial-phase, contrast-enhanced CT images was performed one day after radiofrequency ablation. We used two functions, which were subsets of the fusion imaging, to confirm the location of the hepatocellular carcinoma lesions in the ablated areas and to evaluate the presence or absence of an adequate safety margin. Contrast-enhanced CT was performed one month after the ablation. Two blinded observers reviewed the images obtained using both modalities to evaluate the effect of ablation. RESULTS: When the one-month contrast-enhanced CT images were used as the reference standard, the sensitivity, specificity, and accuracy of the one-day fusion imaging for the diagnosis of adequate ablation were 97%, 83%, and 96%, respectively; the kappa value for the agreement between the findings obtained using the two modalities was 0.75. CONCLUSION: Fusion imaging combining contrast-enhanced ultrasonography images and arterial-phase, contrast-enhanced CT images as a reference appears to be a useful method for the early evaluation of the efficacy of radiofrequency ablation for the treatment of hypervascular hepatocellular carcinoma.