Contrast-enhanced subtraction harmonic sonography for evaluating treatment response in patients with hepatocellular carcinoma

Contrast-enhanced harmonic endoscopic ultrasonography for differential diagnosis of localized gallbladder lesions

BACKGROUND AND AIM

Differential diagnosis of localized gallbladder lesions is challenging. The aim of the present study was to evaluate the utility of contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) for diagnosis of localized gallbladder lesions.

METHODS

One hundred and twenty-five patients with localized gallbladder lesions were evaluated by CH-EUS between March 2007 and February 2014. This was a single-center retrospective study. Utilities of fundamental B-mode EUS (FB-EUS) and CH-EUS in the differentiation of gallbladder lesions and sludge plug were initially compared. Thereafter, these two examinations were compared with respect to their accuracy in the diagnosis of malignant lesions. Five reviewers blinded to the clinicopathological results evaluated microcirculation patterns in the vascular and perfusion images.

RESULTS

In the differentiation between gallbladder lesions and sludge plug, FB-EUS had a sensitivity, specificity, and accuracy of 82%, 100%, and 95%, respectively, whereas CH-EUS had a sensitivity, specificity, and accuracy of 100%, 99%, and 99%, respectively. FB-EUS-based diagnosis of carcinomas based on tumor size and/or shape had a sensitivity, specificity, and accuracy of 61-87%, 71-88%, and 74-86%, respectively. Additional information regarding irregular vessel patterns in the vascular image and/or heterogeneous enhancement in the perfusion image on CH-EUS increased the sensitivity, specificity, and accuracy for the diagnosis of carcinomas to 90%, 98%, and 96%, respectively. There was a significant difference between FB-EUS and CH-EUS in terms of carcinoma diagnosis.

CONCLUSION

CH-EUS was useful for the evaluation of localized gallbladder lesions.

Diagnostic value of contrast-enhanced ultrasound in hepatocellular carcinoma: a meta-analysis with evidence from 1998 to 2016

Background

This meta-analysis is aimed at determining the diagnostic value of hepatocellular carcinoma (HCC) with contrast-enhanced ultrasound (CEUS).

Materials and Methods

A comprehensive literature search of Pubmed, Web of Science, and the Cochrane Library was performed to identify published studies. The methodological quality of the included studies was evaluated. Data from eligible studies were used to estimate the pooled sensitivity, specificity, diagnostic odds ratio (DOR), positive and negative likelihood ratio (LR) and summary receiver operating characteristic (SROC) curve. Meta-Disc and STATA softwares were utilized for all statistical analyses.

Results

Fifty-three eligible studies (publication years ranged from 1998 to 2016) were selected according to inclusion criteria. The meta-analysis showed that the pooled sensitivity and specificity of CEUS to detect HCC were 0.85 (95% CI: 0.84–0.86) and 0.91 (95% CI: 0.90–0.92), respectively. The pooled positive and negative LRs were 6.28 (95% CI: 4.49–8.77) and 0.16 (95% CI: 0.12–0.22), respectively. The pooled DOR was 55.01 (95% CI: 35.25–83.47). The area under the SCOR curve was 0.9432. Meta-regression and funnel plot indicated that sample size, type of contrast agents and publication bias might be the major sources of heterogeneity.

Conclusions

CEUS is a valuable diagnostic tool for identifying HCC in clinic with highly sensitive and specific.

Isolated splenic granuloma: report of a case with an emphasis on ultrasound findings

There is a marked paucity of reports on contrast-enhanced ultrasonography (US) for focal splenic disease in the literature, and there are no previously reported contrast-enhanced US findings for splenic granuloma. We report the case of a 77-year-old cirrhotic woman with isolated splenic granulomas. We detail the diagnostic difficulty encountered in this case and briefly review the literature.

Inflammatory pseudotumor of the spleen: report of a case with emphasis on contrast-enhanced ultrasound findings

Splenic inflammatory pseudotumor is a rare pathology, and the literature stresses the difficulty of preoperative diagnosis. There are no previous reports of contrast-enhanced ultrasound findings for this tumor in the literature. Our case appears to be the first to be examined using this technique. In our case, contrast-enhanced ultrasound showed the mass to be homogeneously and less enhanced than the surrounding parenchyma in all phases, and it included fine enhanced spots. We also briefly review the literature.

Evaluation of transcatheter arterial embolization therapy on hepatocellular carcinomas using contrast-enhanced harmonic power Doppler sonography: comparison with CT, power Doppler sonography, and dynamic MRI

PURPOSE

The aim of this study was to assess and compare the sensitivity of power Doppler sonography, contrast-enhanced sonography, plain computed tomography (CT), and dynamic magnetic resonance imaging (MRI) for detecting hepatocellular carcinoma (HCC) nodules incompletely treated with transcatheter arterial embolization (TAE).

METHODS

A total of 63 unresectable HCC nodules were examined in this study. The HCCs were treated with TAE. All patients underwent plain CT, power Doppler sonography, contrast-enhanced harmonic power Doppler sonography, and dynamic MRI 1 week after TAE. The sensitivity of each modality to incompletely treated HCC nodules was compared. Detection of the residual viable HCC on angiography or tumor biopsy was regarded as the gold standard for the diagnosis of incomplete treatment.

RESULTS

Twenty-four nodules (38%) were diagnosed as incompletely treated. The sensitivities of plain CT, power Doppler sonography, contrast-enhanced harmonic power Doppler sonography, and dynamic MRI to these incompletely treated nodules were 42% (10/24), 46% (11/24), 88% (21/24), and 79% (19/24), respectively. Eighty percent (19 nodules) of the 24 incompletely treated nodules were located within a depth of less than 8 cm. The sensitivities of plain CT, power Doppler sonography, contrast-enhanced harmonic power Doppler sonography, and dynamic MRI to these superficial incompletely treated nodules were 37% (7/19), 53% (10/19), 100% (19/19), and 74% (14/19), respectively. In contrast, the sensitivities of each modality to deeply located nodules were 60% (3/5), 20% (1/5), 40% (2/5), and 100% (5/5), respectively.

CONCLUSION

Plain CT and power Doppler sonography had a low sensitivity to HCC nodules incompletely treated with TAE. Except for those that were deeply located, contrast-enhanced harmonic sonography showed the highest sensitivity in detecting incompletely treated HCC nodules.

Detection of tumor vascularity in hepatocellular carcinoma with contrast-enhanced Dynamic Flow imaging: Comparison with contrast-enhanced power Doppler imaging

OBJECTIVE

To compare the effectiveness of contrast-enhanced Dynamic Flow imaging and contrast-enhanced power Doppler imaging using Levovist(®) as a microbubble contrast agent in evaluating intratumoral vascularity in hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

Twenty-nine patients with 54 hepatocellular carcinoma nodules (before treatment, 31; after treatment, 23) were studied with both Dynamic Flow and power Doppler imaging with intravenous injection of Levovist(®). Tumor vascularity was categorized as 0, no blood flow signals within the tumor; 1, dotlike blood flow signals within the tumor; 2, moderate blood flow signals within the tumor; and 3, abundant blood flow signals within the tumor. Detectability of intratumoral vascularity of hepatocellular carcinoma in three groups based on tumor depth, blooming and noise artifacts on contrast-enhanced Dynamic Flow and contrast-enhanced power Doppler imaging were also compared with results obtained using dynamic CT as a the gold standard. The effectiveness of contrast-enhanced Dynamic Flow and contrast-enhanced power Doppler imaging in assessing therapeutic effect were compared at the same time.

RESULTS

The ability of contrast-enhanced Dynamic Flow Doppler imaging to detect tumor vascularity in the superficial and intermediate hepatocellular carcinoma groups was close to that of contrast-enhanced power Doppler imaging (p>0.05). However, contrast-enhanced Dynamic Flow imaging demonstrated tumor parenchymal stain in 28 hepatocellular carcinoma nodules (61%), which was not detected by contrast-enhanced power Doppler imaging. Further, significantly fewer artifacts appeared in contrast-enhanced Dynamic Flow imaging than in contrast-enhanced power Doppler imaging (p<0.001). In assessing therapeutic response, the sensitivity of contrast-enhanced Dynamic Flow imaging was similar to that of dynamic CT. In deep areas, however, those more than 6 cm below the surface of the body, contrast-enhanced Dynamic Flow imaging was less sensitivity than contrast-enhanced power Doppler imaging (p=0.005).

CONCLUSION

Contrast-enhanced Dynamic Flow imaging provides an effective approach to assessing intratumoral vascularity and therapeutic response in HCC lesions situated less than 6 cm from the surface of the body. It is superior to contrast-enhanced power Doppler imaging in its ability to detect tumor parenchymal stain and production of fewer artifacts.

Qualitative diagnosis of hepatocellular carcinoma by contrast enhanced ultrasonography using Coded Harmonic Angio with Levovist

We attempted to evaluate diagnosis and characterization and to access therapeutic effects in cases of hepatocellular carcinoma (HCC) by contrast enhanced ultrasound (CEUS) using Coded Harmonic Angio (CHA) with Levovist, an intravenous ultrasound contrast agent. Fifty-seven HCC foci in 39 patients, including 37 HCC foci in 28 patients before and after transcatheter arterial chemoembolization or radio frequency ablation, were examined by CEUS using the CHA mode, which is under development. This mode uses digitally encoded pulse sequences that identify and suppress nonmoving tissue signals and enhance contrast signals from Levovist in a gray-scale format. In all cases, abundant tortuous intratumoral blood flow was visualized in the early vascular phase by continuous transmission, while tumor stain was recognized by consecutive 1-to-2 second intermittent transmission. Residual tumor area after treatment was also clearly depicted by intratumoral blood flow and partial enhancement. CEUS using CHA with Levovist is likely to become important in the qualitative diagnosis of hepatic tumor and to improve the efficacy of treatment for HCC.

The usefulness of contrast-enhanced ultrasonography in the early detection of hepatocellular carcinoma viability after transarterial chemoembolization: pilot study

Background/Aims

The therapeutic effect of transarterial chemoembolization (TACE) against hepatocellular carcinoma (HCC) is usually assessed using multidetector computed tomography (MDCT). However, dense lipiodol depositions can mask the enhancement of viable HCC tissue in MDCT. Contrast-enhanced ultrasonography (CEUS) could be effective in detecting small areas of viability and patency in vessels. We investigated whether arterial enhancement in CEUS after treatment with TACE can be used to detect HCC viability earlier than when using MDCT.

Methods

Twelve patients received CEUS, MDCT, and gadoxetic-acid-enhanced dynamic magnetic resonance imaging (MRI) at baseline and 4 and 12 weeks after TACE. The definition of viable HCC was defined as MRI positivity after 4 or 12 weeks.

Results

Eight of the 12 patients showed MRI positivity at 4 or 12 weeks. All patients with positive CEUS findings at 4 weeks (n=8) showed MRI positivity and residual viable HCC at 4 or 12 weeks. Five of the eight patients with positive CEUS findings at 4 weeks had negative results on the 4-week MDCT scan. Four (50%) of these eight patients did not have MRI positivity at 4 weeks and were ultimately confirmed as having residual HCC tissue at the 12-week MRI. Kappa statistics revealed near-perfect agreement between CEUS and MRI (κ=1.00) and substantial agreement between MDCT and MRI (κ=0.67).

Conclusions

In the assessment of the response to TACE, CEUS at 4 weeks showed excellent results for detecting residual viable HCC, which suggests that CEUS can be used as an early additive diagnosis tool when deciding early additional treatment with TACE.

Usefulness of contrast-enhanced ultrasonography to evaluate the post-treatment responses of radiofrequency ablation for hepatocellular carcinoma: comparison with dynamic CT

OBJECTIVE

Contrast-enhanced ultrasonography (CEUS) with Sonazoid® and dynamic computed tomography (CT) were used to evaluate radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC). Local recurrence rate was used as the gold standard of evaluation.

METHODS

From January 2007 to December 2011, 86 HCCs from 70 patients were treated with RFA. CEUS with Sonazoid and dynamic CT were then used to evaluate the effect of RFA. For CEUS and dynamic CT, effects were classified as follows: (1) complete ablated response with safety margin >5 mm (CRSM+); (2) complete ablated response but with safety margin <5 mm (CRSM-); (3) incomplete, residual tumor detected after treatment.

RESULTS

CEUS judged 33 cases as CRSM+, while dynamic CT identified 49 cases. None of these 33 cases from the CEUS group had local recurrences, while dynamic CT had 1 case. CEUS judged 49 cases as CRSM-, compared to 34 cases with dynamic CT. Of these, 9 cases of CEUS and 8 cases of dynamic CT showed local recurrences. Two cases diagnosed as 'incomplete' by CEUS and dynamic CT had recurrences within 1 year.

CONCLUSION

CEUS can be used to assess the efficacy of RFA for HCC, with the potential to reduce the number of CT scans required for confirmation.

Diagnostic imaging of hepatocellular carcinoma: recent progress

The diagnostic imaging of hepatocellular carcinoma (HCC) has recently undergone marked progress. The advent of the ultrasound (US) contrast agent Sonazoid, approved in January 2007, and magnetic resonance imaging (MRI) with the liver-specific MRI contrast agent gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA-MRI), approved in January 2008, are of particular significance. Sonazoid contrast-enhanced US (Sonazoid-CEUS) is useful not only for the diagnosis of HCC, but also for guiding treatment and assessing treatment response. Sonazoid-CEUS has proven to be particularly effective for screening and staging, which used to be considered impossible with CEUS, through the introduction of the newly developed diagnostic technique of defect reperfusion imaging. It is still not possible if other vascular agents such as SonoVue and Definity are used. In particular, Gd-EOB-DTPA-MRI has been suggested to be much more reliable in the differentiation of early HCC from precancerous dysplastic nodules than any other modalities such as multidetector raw computed tomography, dynamic MRI, and superparamagnetic iron oxide-MRI. A decrease in contrast uptake in the hepatocyte phase observed on EOB-MRI is strongly suggestive of cancer, and the absence of early staining in the arterial phase suggests early HCC. The differential diagnostic capacity of Gd-EOB-DTPA-MRI is considered to far exceed that of what were previously the most useful imaging techniques, computed tomography (CT) during hepatic arteriography or CT during arterial portography, and to be comparable to that of the pathological diagnosis by pathologists specialized in liver.

Asian Pacific Association for the Study of the Liver consensus recommendations on hepatocellular carcinoma

INTRODUCTION

The Asian Pacific Association for the Study of the Liver (APASL) convened an international working party on the management of hepatocellular carcinoma (HCC) in December 2008 to develop consensus recommendations.

METHODS

The working party consisted of expert hepatologist, hepatobiliary surgeon, radiologist, and oncologist from Asian-Pacific region, who were requested to make drafts prior to the consensus meeting held at Bali, Indonesia on 4 December 2008. The quality of existing evidence and strength of recommendations were ranked from 1 (highest) to 5 (lowest) and from A (strongest) to D (weakest), respectively, according to the Oxford system of evidence-based approach for developing the consensus statements.

RESULTS

Participants of the consensus meeting assessed the quality of cited studies and assigned grades to the recommendation statements. Finalized recommendations were presented at the fourth APASL single topic conference on viral-related HCC at Bali, Indonesia and approved by the participants of the conference.

Asian Pacific Association for the Study of the Liver consensus recommendations on hepatocellular carcinoma

INTRODUCTION

The Asian Pacific Association for the Study of the Liver (APASL) convened an international working party on the management of hepatocellular carcinoma (HCC) in December 2008 to develop consensus recommendations.

METHODS

The working party consisted of expert hepatologist, hepatobiliary surgeon, radiologist, and oncologist from Asian-Pacific region, who were requested to make drafts prior to the consensus meeting held at Bali, Indonesia on 4 December 2008. The quality of existing evidence and strength of recommendations were ranked from 1 (highest) to 5 (lowest) and from A (strongest) to D (weakest), respectively, according to the Oxford system of evidence-based approach for developing the consensus statements.

RESULTS

Participants of the consensus meeting assessed the quality of cited studies and assigned grades to the recommendation statements. Finalized recommendations were presented at the fourth APASL single topic conference on viral-related HCC at Bali, Indonesia and approved by the participants of the conference.

The 2008 Okuda lecture: Management of hepatocellular carcinoma: from surveillance to molecular targeted therapy

Hepatocellular carcinoma (HCC) is responsible for approximately 600,000-700,000 deaths worldwide. It is highly prevalent in the Asia-Pacific region and Africa, and is increasing in Western countries. Alpha fetoprotein (AFP) alone is insufficient for HCC screening. A combination with other tumor markers, such as PIVKA-II and AFP-L3, and periodical ultrasound surveillance is necessary. Sensitivity of AFP in depicting HCC is highest, followed by PIVKA-II and AFP-L3, but the order of the specificity is inverse, AFP-L3, PIVKA-II, and AFP. Sonazoid-enhanced ultrasound (US) is extremely useful to characterize hepatic tumors equal to or more than multidetector row computed tomography (MDCT). Sonazoid-enhanced US with defect re-perfusion imaging is a breakthrough technique in the treatment of HCC. Defect re-perfusion imaging will markedly change the therapeutic strategy for liver cancer. Gd-EOB-DTPA-magnetic resonance imaging is a newly developed imaging technique in the detection and diagnosis of HCC. It is the most sensitive tool in the differentiation of early HCC from dysplastic nodules. Regarding the treatment strategy, there has been no established systemic chemotherapy for advanced HCC, except for Sorafenib. Empirically, intrahepatic arterial infusion chemotherapy using implanted reservoir port is known to be effective in response rate and overall survival for advanced HCC with vascular invasion. Sorafenib in combination with transcatheter arterial chemoembolization or adjuvant use after ablation or resection will significantly prolong the life expectancy if ongoing clinical trials provide positive results. In conclusion, it is expected that readers will gain deeper insight into the latest progress and updated diagnosis and treatment of HCC described in this review.

Radiological diagnosis of hepatocellular carcinoma

Treatment of hepatocellular carcinomas (HCC) is often complicated by the fact that early HCCs are mostly asymptomatic and the carcinoma is often discovered at an advanced stage. The aim of diagnostic imaging is to detect HCC at an early stage, when curative options are available. In recent years, there have been many efforts to improve early detection of small HCC. The purpose of this article is to describe the pertinent findings of HCCs in non-invasive, diagnostic imaging, including ultrasound, computed tomography, as well as modern magnetic resonance imaging techniques. Special emphasis is given to the frequently addressed difficulties of differentiation of precancerous lesions and small HCCs. A non-invasive diagnostic approach is considered with a review of the literature.

Superiority of CT arterioportal angiography to contrast-enhanced CT and MRI in the diagnosis of hepatocellular carcinoma in nodules smaller than 2 cm

To evaluate the effectiveness of computed tomography (CT) arterioportal angiography in the diagnosis of hepatocellular carcinoma (HCC) in nodules smaller than 2 cm, we compared the findings of CT during arteriography (CTA) and CT during arterial portography (CTAP) with those of enhanced CT and enhanced magnetic resonance imaging (MRI). Sixty-eight nodules smaller than 2 cm in 53 patients with liver cirrhosis were classified into three groups of CTA and CTAP: (group 1) hyperattenuation on CTA, and hypoattenuation on CTAP (56 nodules, 41 patients); (group 2) hypoattenuation on CTA, and hypoattenuation on CTAP (10 nodules, 10 patients); (group 3) hypoattenuation on CTA, and hyperattenuation on CTAP (2 nodules, 2 patients). Histologically, 96% (54/56), 80% (8/10), and 100% (2/2) of the nodules in groups 1, 2 and 3, respectively, were diagnosed as HCC. In group 1, enhanced CT or enhanced MRI confirmed hypervascularity in only 77% (30/39) and venous washout in 21% (8/39). In groups 2 and 3, enhanced CT or enhanced MRI on 7 and 2 nodules, respectively, revealed no hypervascularity (0%). The results suggested that CT arterioportal angiography is superior to enhanced CT and MRI in nodules smaller than 2 cm for diagnosing HCC (p < 0.01 group 1, p < 0.01 group 2).

New sonographic techniques for the diagnosis and treatment of hepatocellular carcinoma

Ultrasound (US) contrast agents such as Levovist and Sonazoid are now commercially available in Japan. Innovative contrast agents and ultrasound technologies have dramatically changed both diagnostic and treatment strategies for hepatocellular carcinoma (HCC). Contrast-enhanced US is extremely useful in the differential diagnosis of hepatic tumors as well as in evaluation of post-treatment response of HCC after lipiodol transarterial chemoembolization and radio frequency ablation. Harmonic US sensitively detects residual cancer cells in HCC patients after treatment, to facilitate accurate guidance for needle insertion for US monitoring; no other imaging modalities, including computed tomography (CT) or magnetic resonance imaging (MRI), have such capability. In 2005, the breakthrough technology of pure arterial phase imaging, which depicts only intranodular arterial accumulated maximum intensity projection images, was developed from advanced raw data storing and accumulation technologies. This technique can clearly identify whether blood supplyin the tumor is of arterial or portal origin, to facilitate the non-invasive characterization of nodular lesions associated with liver cirrhosis. Again, CT or MRI do not have such capabilities. This innovative technique can help differentiate premalignant lesions from overt HCC. Concurrent real-time imaging of multi-detector CT and US, known as real-time virtual sonography, has recently become available. This technique greatly facilitates the treatment guidance for HCC. These newly introduced sonographic techniques are dramatically changing the diagnostic and therapeutic strategies for HCC, which are expected to improve the prognosis of HCC patients.

Elastographic evaluation of the temporal formation of ethanol-induced hepatic lesions: preliminary in vitro results

OBJECTIVE

The purpose of this study was to evaluate the temporal formation of ethanol-induced hepatic lesions using ultrasound elastography.

METHODS

An in vitro porcine liver was used as the specimen, and 4 lesions were created by injection of 2 mL of ethanol. After the ethanol injection, freehand elastography of the lesion from an identical scan plane was obtained during a time series (with an interval of approximately 30 seconds in the first 2 minutes and 1 minute afterward) using a real-time ultrasound scanner. The area of the lesion in the elastographic sequences was calculated to depict the temporal formation of the lesion.

RESULTS

The ethanol-induced lesion on elastography appeared as a low-strain region whose boundary was clear and irregular. The elastographic sequences obtained after the ethanol injection showed that the lesion formed quickly in the first 2 minutes and then changed little in shape. The area of the lesion grew notably in the first 2 minutes after ethanol injection, and then it reached a plateau of about 0.7 cm(2).

CONCLUSIONS

Ultrasound elastography is capable of monitoring the temporal formation of ethanol-induced lesions and is a potential imaging modality to evaluate the response of percutaneous ethanol injection therapy.

Diagnosis of gallbladder diseases by contrast-enhanced phase-inversion harmonic ultrasonography

We evaluated the usefulness of contrast-enhanced ultrasonography(US) for detecting and differentiating gallbladder lesions. Contrast-enhanced coded phase-inversion harmonic US was performed on 90 patients with gallbladder abnormalities. After administering Levovist, we observed the gallbladders in real time. Contrast-enhanced coded phase-inversion harmonic ultrasonography was compared with B-mode US and contrast-enhanced computer tomography (CT) with regard to the sensitivity and specificity in depicting the elevated gallbladder lesions. Furthermore, we assessed how the vascular patterns of the elevated gallbladder lesions depicted by contrast-enhanced US correlated with the diagnosis. Contrast-enhanced US efficiently discriminated true lesions from biliary sludge, unlike B-mode US. Consequently, contrast-enhanced US was more specific (100%) than B-mode US (81%), although their sensitivities were similar (98% and 96%, respectively). Contrast-enhanced US was also more sensitive that contrast-enhanced CT (98% versus 79%), although the two methods were equally sensitive (100% versus 95%). We classified the vascular patterns of the abnormalities depicted by contrast-enhanced US in the 90 cases into types 1 to 4, which represent branch-like, heterogeneous, homogeneous, and avascular patterns, respectively. All type 1 and 2 lesions were over 10 mm in size while most (88%) type 3 lesions were 10 mm or less in size. While the majority of carcinomas (86%) were type 1 or 2, three benign lesions also showed these patterns. Thus, the vascular pattern may simply reflect the size of the lesion and therefore its usefulness in diagnosing gallbladder lesions may be limited. Nevertheless, contrast-enhanced US is clearly superior to the other techniques in discriminating biliary sludge from other lesions.

The role of contrast-enhanced sonography of focal liver lesions before percutaneous biopsy

OBJECTIVE

The objective of our study was to evaluate the clinical utility of performing contrast-enhanced sonography before percutaneous biopsy of focal liver lesions.

SUBJECTS AND METHODS

One hundred eighty-six patients with focal liver lesions detected on either sonography or contrast-enhanced CT were randomly divided into two groups: a group who underwent contrast-enhanced sonography and another who underwent unenhanced sonography. The contrast-enhanced sonography group (79 patients, 129 lesions) underwent SonoVue-enhanced sonography before biopsy, and the unenhanced sonography group (107 patients, 143 lesions) did not undergo contrast-enhanced sonography before biopsy. Conventional sonography was used in all patients to guide the biopsy procedures. The pathologic diagnosis was considered definitive and final if the biopsy result was malignant. If the initial biopsy result was benign or negative for malignancy, then the result was either confirmed or denied on the basis of contrast-enhanced CT, MRI, angiography, serum alpha-fetoprotein level, or clinical follow-up over a period of 6 months. In some patients with suspected malignancy, biopsy was repeated when considered necessary during the follow-up. The diagnostic accuracy of the initial biopsy was defined as the percentage of the total number of lesions that were correctly diagnosed at the initial biopsy. The difference in diagnostic accuracy between the two groups was analyzed to evaluate the value of performing contrast-enhanced sonography before biopsy.

RESULTS

Of the 129 lesions in the contrast-enhanced sonography group, 28 (21.7%) were benign and 101 (78.3%) were malignant. Of the 143 lesions in the unenhanced sonography group, 36 (25.2%) were benign and 107 (74.8%) were malignant. There was no significant difference in the distribution of malignant and benign lesions in these two groups (p > 0.05). There was no statistically significant difference in the distribution of lesions by size between the contrast-enhanced and unenhanced sonography groups (chi(2) = 0.619, p > 0.05). The diagnostic accuracy of the initial biopsy was significantly higher in the contrast-enhanced sonography group than in the unenhanced sonography group (95.3% vs 87.4%, respectively; p < 0.05). The diagnostic accuracy of the initial biopsy for malignant lesions < or = 2.0 cm was also significantly higher in the contrast-enhanced sonography group than in the unenhanced sonography group (97.1% vs 78.8%, respectively; p < 0.05). No major complications occurred in our study except one case of pneumothorax in the unenhanced sonography group.

CONCLUSION

Contrast-enhanced sonography before percutaneous focal liver lesion biopsy improved the diagnostic accuracy of the procedure by providing important intralesional information for differentiating viable, denaturalized, or necrotic tissue; consequently, by providing more accurate information about the site of biopsy even in lesions < or = 2.0 cm, contrast-enhanced sonography before biopsy reduced the number of puncture attempts.

A computer-aided temporal and dynamic subtraction technique of the liver for detection of small hepatocellular carcinomas on abdominal CT images

It is often difficult for radiologists to identify small hepatocellular carcinomas (HCCs) due to insufficient contrast enhancement. Therefore, we have developed a new computer-aided temporal and dynamic subtraction technique to enhance small HCCs, after automatically selecting images set at the same anatomical position from the present (non-enhanced and arterial-phase CT images) and previous images. The present study was performed with CT images from 14 subjects. First, we used template-matching based on similarities in liver shape between the present (non-enhanced and arterial-phase CT images) and previous arterial-phase CT images at the same position. Temporal subtraction images were then obtained by subtraction of the previous image from the present image taken at the same position of the liver. Dynamic subtraction images were also obtained by subtraction of non-enhanced CT images from arterial-phase CT images taken at the same position of the liver. Twenty-one of 22 nodules (95.5%) with contrast enhancement were visualized in temporal and dynamic subtraction images. Compared with present arterial-phase CT images, increases of 150% and 140% in nodule-to-liver contrast were observed on dynamic and temporal subtraction images, respectively. These subtraction images may be useful as reference images in the detection of small moderately differentiated HCCs.

Isolated liver metastasis from a renal cell carcinoma 12 years after nephrectomy: report of a case and literature review

We present a rare case of isolated liver metastasis from renal cell carcinoma 12 years after complete resection of the primary site. Such abnormal behavior of renal cell carcinoma has been reported elsewhere in the literature; thus, careful long-term surveillance should be performed in patients with a past history of renal cell carcinoma, even after radical resection of the primary site. We present also contrast-enhanced sonographic findings for this case.

Is microbubble-enhanced ultrasonography sufficient for assessment of response to percutaneous treatment in patients with early hepatocellular carcinoma?

The objective of this study was to assess the efficacy of contrast-enhanced ultrasonography (CEUS) with SonoVue to evaluate the response to percutaneous treatment (ethanol injection/radiofrequency) of hepatocellular carcinoma in comparison with spiral computed tomography (CT) immediately and 1 month after treatment. Forty-one consecutive cirrhotic patients with early stage tumor (not suitable for resection) were included. Spiral CT and CEUS were performed in all patients before treatment, in the following 24 h, and 1 month later. The results of each examination were compared with the 1-month spiral CT, considered the gold standard technique. The 24-h CEUS and the 24-h spiral CT sensitivity to detect residual disease were 27% and 20%, respectively. The 24-h CEUS and the 24-h spiral CT positive predictive value of persistent vascularization detection were 75% and 66%, respectively. The 1-month CEUS detected partial responses in ten out of 11 cases (91% sensitivity, 97% specificity, 95% accuracy). Spiral CT and CEUS performed in the 24 h following treatment are slightly useful to evaluate therapeutic efficacy. The 1-month CEUS has a high diagnostic accuracy compared with spiral-CT in the usual assessment of percutaneous treatment response.

Flash-echo contrast sonography in the evaluation of response of small hepatocellular carcinoma to percutaneous ablation

PURPOSE

To evaluate the use of flash-echo contrast sonography (FECS) in subtraction mode in assessing small hepatocellular carcinoma (HCC) after percutaneous local ablation therapy.

METHODS

Between March 2000 and February 2002, we prospectively assessed small HCCs after percutaneous local ablation therapy using FECS in subtraction mode. Thirty-three patients (22 men, 11 women) with 35 tumors ranging in size from 1.1 to 3.0 cm (mean +/- SD, 2.0 +/- 0.5) were enrolled. Twenty-one tumors received percutaneous ethanol injection only, 13 tumors received percutaneous microwave ablation therapy only, and the remaining tumor received both treatments. CT, hepatic angiography, and follow-up were used as gold standards in analyzing the accuracy of FECS in detecting residual tumors.

RESULTS

The agreements between FECS and CT, FECS and hepatic angiography, and all 3 imaging modalities were 80% (28/35), 85.7% (30/35), and 77.1% (27/35), respectively. Twenty-one patients with 23 completely ablated tumors were followed up for 5 to 39 months (mean +/- SD, 20.2 +/- 11.2). Recurrent disease was detected in 11 (52.4%) patients; local tumor recurrence occurred in 4 (17.4%) patients. The sensitivity, specificity, accuracy, and positive and negative predictive value of FECS in detecting viable tumors were 53.8% (7/13), 90.9% (20/22), 77.1% (27/35), 77.8% (7/9), and 76.9% (20/26), respectively.

CONCLUSIONS

FECS in subtraction mode shows good agreement with hepatic angiography and CT in the assessment of small HCC after percutaneous local ablation therapy. The sensitivity of FECS in detecting residual tumors is suboptimal.

Assessment of the therapeutic response of hepatocellular carcinoma treated with transcatheter arterial chemoembolization: comparison of contrast-enhanced sonography and 3-phase computed tomography

OBJECTIVE

The purpose of this study was to compare contrast-enhanced sonography with 3-phase computed tomography (CT) in assessing the therapeutic response of hepatocellular carcinomas (HCCs) treated with transcatheter arterial chemoembolization (TACE).

METHODS

Twenty-nine nodular HCCs treated with TACE were examined with contrast-enhanced sonography, 3-phase helical CT, and conventional angiography. Contrast-enhanced sonographic and CT findings were interpreted separately and prospectively for the presence or absence of contrast enhancement in the treated HCCs. Conventional angiography served as the reference standard.

RESULTS

Intratumoral enhancement was seen in 19 HCCs (61%) on contrast-enhanced sonography and 12 HCCs (39%) on CT. Enhancement patterns on sonography were blush in 8 (42%), branching in 2 (11%), nodular in 4 (21%), and stippled in 5 (26%). Of the 19 HCCs with intratumoral enhancement on contrast-enhanced sonography, 13 (68%) showed tumor staining on angiography. Of the 12 HCCs without intratumoral enhancement on sonography, 1 (8%) showed tumor staining on angiography. The sensitivity and specificity of contrast-enhanced sonography in depicting flow in HCCs treated with TACE were 93% and 65%, respectively. The sensitivity and specificity of 3-phase CT were 64% and 100%.

CONCLUSIONS

Contrast-enhanced sonography is a more sensitive imaging method than 3-phase CT in depicting vascularity in HCCs treated with TACE.

Malignant fibrous histiocytoma of the spleen: report of a case and literature review

There is a marked paucity of reports on malignant fibrous histiocytoma (MFH) of the spleen in the literature, and there are no previous reports of its color Doppler sonographic (US) and contrast-enhanced US findings. We report on an 82-year-old male with splenic MFH (inflammatory subtype), with an emphasis on color Doppler and contrast-enhanced US findings.

Gallbladder adenoma: report of a case with emphasis on contrast-enhanced US findings

There is a marked paucity of contrast-enhanced ultrasound (US) findings of gallbladder disease in the literature, and there is only one previous case of gallbladder adenoma. We report such a case. US showed a 2-cm polypoid lesion at the gallbladder body. Color Doppler US showed the hypervascular nature of the lesion, and contrast-enhanced US revealed the lesion to be homogeneously enhanced, suggesting that the lesion was composed of the same pathology. The lesion was surgically resected, and was found to be an adenoma without cancer foci. This case suggests that contrast-enhanced US is an effective tool in diagnosing a gallbladder adenoma.

Hepatic angiomyolipoma: identification of an efferent vessel as a hepatic vein by contrast-enhanced harmonic sonography

Two cases of hepatic angiomyolipoma were studied by contrast-enhanced harmonic sonography. The special tumor hemodynamics, namely the efferent blood flow of the hepatic angiomyolipoma draining into the hepatic vein, were clearly shown on harmonic imaging, and they corresponded well with those seen on angiography and computed tomography during angiography. Benign hepatic tumors were diagnosed preoperatively in both cases according to the hemodynamic findings. Hepatic angiomyolipoma was finally identified histologically. The special tumor hemodynamics might be one of the important characteristics of hepatic angiomyolipoma. Contrast-enhanced harmonic sonography is useful for the detection of special tumor hemodynamics and may facilitate the differential diagnosis from other hepatic tumors, especially malignant liver tumors.

Hemodynamic and morphologic changes of peripheral hepatic vasculature in cirrhotic liver disease: A preliminary study using contrast-enhanced coded phase inversion harmonic ultrasonography

AIM: To provide the useful information for the diagnosis of liver cirrhosis by observing the morphology of peripheral hepatic vessels and the hemodynamics of microbubble arrival time in these vessels.

METHODS: Twenty-one subjects including 5 normal volunteers and 16 patients (liver cirrhosis, n=10; chronic hepatitis, n=6) were studied by contrast-enhanced coded phase inversion harmonic sonography (GE LOGIQ 9 series) using a 6-8 MHz convex-arrayed wide-band transducer. The images of peripheral hepatic artery, portal and hepatic vein were observed in real-time for about 2 min after intravenous injection of Levovist. The time when microbubbles appeared in the peripheral vessels (microbubble arrival time) was also recorded. The morphologic changes of peripheral hepatic vasculature were classified as marked, slight, and no changes based on the regularity in caliber, course, ramification, and the delineation of vessels compared to normal subjects.

RESULTS: The microbubble arrival time at peripheral artery, portal, and hepatic vein was shorter in cirrhotic patients than in chronic hepatitis patients and normal subjects. The marked, slight and no morphologic changes of peripheral hepatic vasculature found in 5 (5/6, 83.3%), 1 (1/6, 16.7%), and 0 (0/6, 0%) liver cirrhosis patients, respectively, and in 1 (1/10, 10%), 6 (6/10, 60%), and 3 (3/10, 30%) chronic hepatitis patients, respectively. There was a significant difference between the two groups (P<0.001).

CONCLUSION: Evaluation of the hemodynamics and morphology of peripheral hepatic vasculature by contrast-enhanced coded pulse inversion harmonic sonography can provide useful information for the diagnosis of liver cirrhosis.

Duodenal adenoma with production of massive mucus: report of a case with emphasis on US findings

Duodenal adenoma with massive mucus production is very rare. We report such a case. Ultrasonography (US) showed the presence of massive mucus, and contrast- enhanced US revealed the thickened wall to be homogeneously enhanced, suggesting that the lesion was composed of the same pathology. The US results were confirmed histologically by endoscopically guided biopsy. Thus, contrast-enhanced US helps determine the biopsy point and determine good diagnostic strategies.

Hepatic angiomyolipoma: identification of an efferent vessel to be hepatic vein by contrast-enhanced harmonic ultrasound

We report two patients with rare hepatic angiomyolipoma and demonstrate the special tumour haemodynamics with contrast-enhanced harmonic ultrasound. This reliably identified the efferent vessel of the hepatic angiomyolipoma to be the hepatic vein in both cases, which corresponded well with that seen on conventional angiography and CT angiography. This haemodynamic finding may be an important characteristic of hepatic angiomyolipoma, and facilitate the differential diagnosis from other benign and malignant hepatic tumours.

Imaging of focal liver lesions: low-mechanical-index real-time ultrasonography with SonoVue

OBJECTIVE

The purpose of this study was to evaluate the usefulness of a contrast-enhanced contrast-specific ultrasonographic technique with a low mechanical index for characterization of focal liver lesions.

METHODS

Contrast-specific ultrasonography was used to assess 144 patients with 147 focal liver lesions: 87 primary liver carcinomas, 27 hemangiomas, 16 focal nodular hyperplasias, 5 hepatic abscesses, 3 inflammatory pseudotumors of the liver, and 9 metastases. A sulfur hexafluoride gas-based contrast agent was used with a mechanical index of 0.08 to 0.11.

RESULTS

On contrast-enhanced ultrasonography, the typical hemodynamic pattern of primary liver carcinoma was the whole-lesion enhancement or mosaic enhancement in the arterial phase with an enhancement defect in the late phase (sensitivity, 92.0%; specificity, 86.7%). The most common enhancement pattern of hemangioma was that enhancement appeared in the periphery first and progressively filled into the lesion center (sensitivity, 96.3%; specificity, 97.5%). The enhancement pattern of focal nodular hyperplasia was that the whole lesion enhanced early and rapidly in the arterial phase with a centrifugal radiating configuration and appeared isoechoic or hyperechoic until the late phase (sensitivity, 87.6%; specificity, 94.5%). The central scar was detected in 31.3% of cases in the late phase. The specific enhancement of a hepatic abscess was the honeycomblike enhancement in all phases (sensitivity, 80.0%; specificity, 100%). No enhancement of a lesion in all phases was specific for an inflammatory pseudotumor of the liver.

CONCLUSIONS

Contrast-enhanced real-time ultrasonography is a promising approach in the noninvasive characterization of focal liver lesions and can be useful as a first-line imaging technique clinically when a focal liver lesion is detectable on ultrasonography.

Treatment of hepatocellular carcinoma with percutaneous radiofrequency ablation: usefulness of contrast harmonic sonography for lesions poorly defined with B-mode sonography

OBJECTIVE

The purpose of this study was to assess the usefulness of contrast harmonic sonography guidance in percutaneous radiofrequency ablation of hepatocellular carcinomas that could not be adequately depicted by B-mode sonography. SUBJECTS AND METHODS. Twenty-one patients with 21 hepatocellular carcinomas prospectively underwent radiofrequency ablation treatment with contrast harmonic sonography as guidance. Twenty-five patients with 25 hepatocellular carcinomas were retrospectively selected as the historical control group under the same conditions as the study group; the control group patients were treated under B-mode sonography guidance.

RESULTS

Twenty (95.2%) of the 21 patients were successfully treated during a single treatment session, and the remaining patient (4.8%) required two treatment sessions with contrast harmonic guidance. On the other hand, only eight (32%) of the 25 control subjects were successfully treated during a single treatment session using B-mode sonographic guidance without contrast imaging. The difference between these two groups was statistically significant (p = 0.002).

CONCLUSION

Contrast harmonic sonography helps in the placement of radiofrequency ablation electrodes in hypervascular hepatocellular carcinomas that cannot be adequately depicted by B-mode sonography.

Dynamic imaging of pancreatic diseases by contrast enhanced coded phase inversion harmonic ultrasonography

BACKGROUND

Coded phase inversion harmonic ultrasonography, a newly available sonographic technique, enables visualisation of slow flow in minute vessels in a real time fashion with the use of a sonographic contrast agent containing monosaccharide. Our purpose was to employ this novel technique to observe microvessels in pancreatic tumours.

SUBJECTS AND METHODS

Sixty five patients with suspicious pancreatic tumours received contrast enhanced coded phase inversion harmonic ultrasonography, contrast enhanced computed tomography, and endosonography. Final diagnoses based on histological findings were pancreatic ductal carcinomas in 49 patients, inflammatory pseudotumours with chronic pancreatitis in seven, and endocrine tumours in nine. For contrast enhanced coded harmonic ultrasonography, Levovist, a contrast agent, was injected intravenously as a bolus. When the first microbubble signal appeared in the pancreas, images of the ideal scanning plane were displayed in a real time continuous fashion (vessel images). Subsequently, interval delay scanning (perfusion images) was taken to demonstrate parenchymal flow. Tumour vascularity was evaluated by using the two types of imaging. Sensitivities for depicting pancreatic tumours were compared between three examinations.

RESULTS

Contrast enhanced ultrasonography demonstrated tumour vessels in 67% of pancreatic ductal carcinomas, although most were relatively hypovascular compared with the surrounding pancreatic tissue. The vascular patterns of tumours obtained by contrast enhanced ultrasonography were closely correlated with those obtained by contrast enhanced computed tomography. Values for sensitivity in depicting pancreatic tumours of 2 cm or less in size were 68% for contrast enhanced computed tomography, 95% for endosonography, and 95% for contrast enhanced ultrasonography.

CONCLUSION

Contrast enhanced coded phase inversion harmonic ultrasonography successfully visualised fine vessels in pancreatic tumours and may play a pivotal role in the depiction and differential diagnosis of pancreatic tumours.

Contrast-enhanced power Doppler sonography of ductal pancreatic adenocarcinomas: correlation with digital subtraction angiography findings

PURPOSE

The purpose of this prospective study was to utilize contrast-enhanced power Doppler sonography to evaluate the enhancement characteristics of ductal pancreatic adenocarcinomas and correlate them with the tumor vascularity observed on digital subtraction angiography (DSA).

METHODS

Twenty consecutive patients with ductal pancreatic adenocarcinoma underwent power Doppler sonography and DSA. Tumor vascularity was assessed using unenhanced and contrast-enhanced power Doppler sonography. The contrast agent Levovist was administered intravenously by bolus injection of a dose of 2.5 g at a concentration of 350 mg/mL; saline was administered immediately thereafter. The patients were asked to hold their breath for 30 seconds (for the period 15-45 seconds after saline injection) while the early phase of enhancement was studied; the delayed phase of enhancement was observed between 60 and 120 seconds after saline administration, while patients breathed gently.

RESULTS

None of the 20 pancreatic carcinomas showed any color signals on power Doppler sonography before administration of the contrast medium. Seventeen (85%) of the 20 pancreatic carcinomas also showed no enhancement in the early and delayed phases of contrast-enhanced power Doppler sonography. However, in the early phase of contrast-enhanced power Doppler sonography; 1 lesion showed pronounced enhancement and 2 showed mild enhancement. On DSA, the 17 carcinomas showing no enhancement on power Doppler sonography were found to be hypovascular, whereas the remaining 3 carcinomas with contrast enhancement on power Doppler sonography were found to be hypervascular.

CONCLUSIONS

The enhancement characteristics of the ductal pancreatic adenocarcinomas correlated well with the tumor vascularity observed on DSA. However, further study is needed to determine the accuracy of contrast-enhanced sonography in the diagnosis of pancreatic masses.

Qualitative assessment of tumor vascularity in hepatocellular carcinoma by contrast-enhanced coded ultrasound: comparison with arterial phase of dynamic CT and conventional color/power Doppler ultrasound

The purpose of this study was to evaluate the detection rate of tumor vessels and vascularity in hepatocellular carcinoma (HCC) by contrast-enhanced coded US using Levovist, and to compare with conventional color/power Doppler US (CDUS) and dynamic CT. Ninety nodules (72 hypo/isoechoic nodules, 18 hyperechoic nodules) in 61 patients were studied. We observed tumor vessels by continuous transmission at the early vascular phase (40 s following administration of Levovist) and vascularity by intermittent transmission (intervals of 2-3 s) at the late vascular phase (40 to approximately 120 s). The detection rate of tumor vessels at the early vascular phase was 97% in hypo/isoechoic nodules and 70% in hyperechoic nodules with high density in dynamic CT being higher than that by CDUS. Tumor vascularity at the late vascular phase in hypo/isoechoic and hyperechoic nodules was hyper-enhancement in 78 and 40%, iso-enhancement in 19 and 40%, and hypo-enhancement in 3 and 0%, respectively. The detection rates of tumor vessels and vascularity in hyperechoic nodules were similar to those by CDUS. The detection rates of tumor vessels and vascularity were not affected by the tumor size in HCC tumors with high density in dynamic CT. Contrast-enhanced US with Levovist was superior to CDUS and equal to dynamic CT to assess tumor vessels in hypo/isoechoic nodules. Although it was equal to CDUS for hyperechoic nodules, this modality is useful in evaluating tumor hemodynamics.

Differential diagnosis of hepatic tumors by using contrast enhancement patterns at US

PURPOSE

To assess the accuracy of pattern-based classification of contrast material-enhanced wideband harmonic gray-scale ultrasonographic (US) images in the differential diagnosis of hepatic tumors.

MATERIALS AND METHODS

A total of 183 hepatic lesions in 183 patients were studied; lesions included 116 hepatocellular carcinomas, 42 liver metastases, and 25 liver hemangiomas. After injection of a galactose-palmitic acid contrast agent, lesions were scanned with contrast-enhanced wideband harmonic gray-scale US in the arterial, portal venous, and late venous phases. The enhancement patterns were classified, and multiple logistic regression analysis was used to identify diagnostic patterns that enabled differentiation between hepatic tumors.

RESULTS

Five enhancement patterns were found to be significant in predicting different hepatic tumors. In hepatocellular carcinomas, the presence of intratumoral vessels in the arterial phase and homogeneous or heterogeneous enhancement in the portal phase were the most typical patterns. In metastases, the absence of intratumoral vessels in the arterial phase and ring enhancement or a perfusion defect in the portal phase were the most typical patterns. In hemangiomas, the absence of intratumoral vessels in the arterial phase and peripheral nodular enhancement in the portal phase were the most typical patterns. The sensitivity, specificity, and accuracy of diagnosis based on combinations of enhancement patterns were, respectively, 94.8%, 94.0%, and 94.5% for hepatocellular carcinoma; 90.5%, 94.3%, and 93.4% for metastasis; and 88.0%, 99.4%, and 97.8% for hemangioma.

CONCLUSION

Contrast-enhanced wideband harmonic gray-scale US is a useful tool for differentiating among the hepatic tumors studied.

Characterization of focal hepatic lesions with contrast-enhanced C-cube gray scale ultrasonography

AIM: To characterize enhancement patterns of focal hepatic lesions using C-cube gray scale sonography with a microbubble contrast agent and to evaluate its usefulness in differential diagnosis of hepatic lesions.

METHODS: Fifty-four patients with 58 focal hepatic lesions were examined with Levovist-enhanced C-cube gray scale sonography. The final diagnosis of hepatic lesions was 29 primary liver cancers, 4 metastases, 8 hemangiomas, 12 focal nodular hyperplasias, 2 inflammatory pseudotumors of the liver and 3 angiomyolipomas. The initiation time of enhancement in various lesions and enhancement duration after administration of contrast agent were compared. Vascular findings in lesions were classified as peripheral enhancement, homogenous enhancement, mosaic enhancement and no enhancement depending on microbubble signals in the lesion relative to the liver parenchyma.

RESULTS: The initiation time of enhancement in hemangioma (48 ± 12 s) was significantly later compared to other lesions (P < 0.05). The enhancement duration of malignancies (69 ± 33 s in primary liver cancer, 61 ± 23 s in metastasis) was significantly shorter compared to benign lesions (P < 0.05). Intranodular enhancement appearing at arterial phase and decreasing at portal venous phase was considered characteristic for malignancy. Intranodular enhancement did not appear earlier than the liver parenchyma, and peripheral enhancement pattern was regarded as positive findings for hemangioma. Intranodular enhancement appeared in the arterial phase, and homogenous enhancement pattern sustained in the whole portal venous phase were regarded as positive findings for focal nodular hyperplasia. No microbubble signals appeared in two inflammatory pseudotumors of the liver.

CONCLUSION: C-cube gray scale sonography can demonstrate dynamic intranodular enhancement in various focal hepatic lesions. The information provided by this methodology may be useful in the differential diagnosis of hepatic lesions.

Radiofrequency ablation of hepatocellular carcinoma: therapeutic response using contrast-enhanced coded phase-inversion harmonic sonography

OBJECTIVE

This study was performed to evaluate the usefulness of contrast-enhanced coded phase-inversion harmonic sonography in assessing the therapeutic response of percutaneous radiofrequency ablation in patients with hepatocellular carcinoma.

SUBJECTS AND METHODS

Sixty-seven patients with a total of 107 examinations on 91 hepatocellular carcinoma nodules underwent coded harmonic angio, a technique of coded phase-inversion harmonic sonography, using the IV microbubble contrast agent Levovist before and after percutaneous radiofrequency ablation. The intratumoral blood vessels and tumor parenchymal stain were detected in the early arterial phase and the late vascular phase, respectively. The results of contrast-enhanced imaging with coded harmonic angio were compared with those of three-phase dynamic CT.

RESULTS

Before treatment, all examined 107 hepatocellular carcinoma nodules were found to be hypervascular on contrast-enhanced imaging with coded harmonic angio. After radiofrequency ablation, contrast-enhanced coded harmonic angio detected persistent signal enhancement in 41 examined nodules (38.3%), whereas this technique showed no intratumoral enhancement in the remaining 66 (61.7%) examined nodules. Compared with dynamic CT, the sensitivity, specificity, and diagnostic accuracy of contrast-enhanced coded harmonic angio were 95.3%, 100%, and 98.1%, respectively. With contrast-enhanced coded harmonic angio, we found that it was difficult to identify the safety margin that can be detected on dynamic CT.

CONCLUSION

Contrast-enhanced imaging with coded harmonic angio may provide an alternative approach that has high diagnostic agreement with dynamic CT in assessing the therapeutic effect of radiofrequency ablation in hypervascular hepatocellular carcinomas, in spite of having limitations in identifying the safety margin.

Contrast enhancement patterns of hepatic tumours during the vascular phase using coded harmonic imaging and Levovist to differentiate hepatocellular carcinoma from other focal lesions

The purpose of the study was to assess contrast enhancement patterns of hepatic tumours during the vascular phase using contrast-enhanced ultrasound and Levovist to differentiate hepatocellular carcinoma from other hepatic tumours. 89 hepatic tumours in 82 consecutive patients were evaluated using coded harmonic ultrasound imaging. The procedure used a phase inversion harmonic technique and coded technology. We observed images for 2 min from the beginning of the administration as the vascular phase using continuous transmission and intermittent transmissions of 1 s or 2 s. The contrast agent Levovist was administered intravenously as a bolus infusion of 2.5 g. Tumour vessels with flow spreading into the tumour and/or homogeneously stained hyperechoic images were observed in 34 of the 41 hepatocellular carcinomas (sensitivity, 82.9%; specificity, 93.8%). Peripheral enhancements were characteristic of intrahepatic cholangiocarcinoma and metastatic hepatic tumours (sensitivity, 60.0% and 83.3%; specificity, 65.5% and 76.4%, respectively). Pooling at the periphery or throughout the tumour was apparent only in haemangioma (sensitivity, 76.5%; specificity, 100%). A tortuous feeding artery and spoke-like vascularization were evident only in the two focal nodular hyperplasias. Contrast-enhanced ultrasound using coded harmonic ultrasound imaging and Levovist provided detailed information about tumour vascularity and contrast enhancement patterns in hepatic tumours.

Transcatheter arterial chemoembolization of hepatocellular carcinoma: usefulness of coded phase-inversion harmonic sonography

OBJECTIVE

The purpose of our study was to assess the value of coded phase-inversion harmonic sonography performed approximately 1 week after the patients had undergone transcatheter arterial chemoembolization with iodized oil for hepatocellular carcinoma.

SUBJECTS AND METHODS

We studied 40 patients with 44 nodules measuring 1.5-11.0 cm in diameter (mean +/- SD, 3.9 +/- 2.0 cm) who underwent transcatheter arterial chemoembolization. Coded phase-inversion harmonic sonography, a technique based on a combination of phase-inversion harmonics and coded technology, was performed with a contrast agent approximately 1 week after chemoembolization. The results were compared with those obtained using dynamic CT (n = 44 lesions) and dynamic MR imaging (n = 20 lesions). We also evaluated the recurrence of hepatocellular carcinoma during clinical follow-up in 17 patients who did not undergo additional local therapy.

RESULTS

The detection rates of intratumoral vascularity of coded phase-inversion harmonic sonography, dynamic CT, and dynamic MR imaging were, respectively, 38 (86%) of 44 lesions, 19 (43%) of 44 lesions, and 10 (50%) of 20 lesions. Of 19 nodules of hepatocellular carcinoma treated only by transcatheter arterial chemoembolization, 17 nodules showed enhancement on coded phase-inversion harmonic sonography, suggesting incomplete responses. In all 17 nodules, apparent recurrence was noted on dynamic CT during clinical follow-up, even in nodules that had been observed to be completely filled with iodized oil 1 week after the chemoembolization.

CONCLUSION

We found coded phase-inversion harmonic sonography to be highly sensitive and accurate for evaluating the treatment response in patients with hepatocellular carcinoma even shortly after treatment. Consequently, it allows early recognition of the need for additional local ablation therapy and estimation of the risk of hepatocellular carcinoma recurrence.

Assessment of image quality of contrast-enhanced power doppler imaging in hepatocellular carcinoma with the personal ultrasound imager: Comparison with the conventional machine

OBJECTIVE

To evaluate the usefulness of contrast-enhanced power Doppler imaging with the personal ultrasound imager in depicting intratumoral vascularity in hepatocellular carcinoma.

MATERIALS AND METHODS

Contrast-enhanced power Doppler imaging was used to examine 52 hepatocellular carcinoma nodules in 29 patients, using both the personal ultrasound imager and the conventional ultrasound machine in combination with intravenous injection of Levovist(®). Results obtained using dynamic CT were used as the gold standard. The ability of the personal ultrasound imager to detect intratumoral vascularity was compared with that of the conventional ultrasound machine, and the usefulness of the personal ultrasound imager in assessing therapeutic effect after nonsurgical treatment was compared with that of dynamic CT at the same time.

RESULTS

The personal ultrasound imager and the conventional ultrasound machine, using the fundamental power Doppler imaging mode (p=0.13) and contrast-enhanced power Doppler imaging mode (p=0.41), did not differ significantly in depicting the vascularity of the 52 hepatocellular carcinomas. The sensitivity, specificity, and accuracy of contrast-enhanced power Doppler imaging on the personal ultrasound imager were 95.5%, 87.5%, and 94.2%, respectively, in close agreement with results obtained using dynamic CT. After the 22 hepatocellular carcinomas were treated, the personal ultrasound imager provided diagnostic accuracy of 90.9% on residual tumors when compared with results obtained by dynamic CT, and results obtained using the conventional ultrasound machine were similar.

CONCLUSION

The highly portable personal ultrasound imager using Levovist(®)-enhanced power Doppler imaging can clearly depict the intratumoral vascularity of hepatocellular carcinoma nodules before and after treatment, achieving results very close to those obtained using the conventional diagnostic ultrasound machine. The personal ultrasound imager is an alternative to the conventional ultrasound machine for depicting tumor vascularity.

Contrast-enhanced power Doppler sonography and helical computed tomography for assessment of vascularity of small hepatocellular carcinomas before and after percutaneous ablation

PURPOSE

We compared the usefulness of Levovist-enhanced power Doppler imaging (PDI) and helical CT in the depiction of tumor vascularity before and after percutaneous ablation of small hepatocellular carcinomas (HCCs).

METHODS

Thirty-one cirrhotic patients with solitary unresectable HCCs smaller than 5 cm (mean size, 2.7 +/- 0.8 cm; range, 1.5-5.0 cm) recruited over a 15-month period were treated with percutaneous ethanol injection (n = 9) or radiofrequency ablation (n = 22). PDI, contrast-enhanced PDI (using Levovist), and multiphase contrast-enhanced helical CT were performed before and after percutaneous ablation, and vascularity findings were compared.

RESULTS

Levovist significantly increased baseline intratumoral Doppler signals on PDI compared to non-contrast PDI. The most frequent tumor vascularity pattern was heterogeneous (45%). Vascularity was identified in all tumors by both contrast-enhanced PDI and helical CT before ablation. After percutaneous ablation, intratumoral vascularity was detected in 11 tumors by contrast-enhanced PDI and in 15 tumors by CT. The sensitivity, specificity, and diagnostic accuracy of contrast-enhanced PDI in demonstrating intratumoral vascularity, with CT being the gold standard, were 66%, 93%, and 81%, respectively. There was significant agreement between the 2 modalities in the depiction of tumor vascularity after ablation (kappa = 0.6, p = 0.001). However, there were 5 false negatives and 1 false positive with contrast-enhanced PDI. Complete tumor necrosis was achieved in 21 patients (68%).

CONCLUSIONS

There was a good concordance between contrast-enhanced PDI and helical CT in the depiction of HCC vascularity before and after percutaneous ablation. However, although contrast-enhanced PDI may be useful for real-time guidance of treatment, its low sensitivity makes it inadequate to accurately assess the completeness of ablation.