Sonography with intraarterial infusion of carbon dioxide microbubbles (sonographic angiography): value in differential diagnosis of hepatic tumors

Ultrasonographic Angiography in Gallbladder Diseases

Ultrasonographic (US) angiography was performed by sonographic examination with injection of carbon dioxide microbubbles through a catheter following conventional angiography in 41 patients with various gallbladder diseases. Three enhancement patterns were found; strong enhancement in the lesion from the periphery to the center was noted in patients with adenocarcinoma and benign polyp (type I), irregular partial enhancement at the margins of the lesion in those with adenosquamous carcinoma (type II), and internal regular enhancement in those with chronic cholecystitis, xanthogranulomatous cholecystitis and adenomyomatosis (type III). Pseudopolypoid lesion such as gallbladder debris showed no enhancement. US angiography may be useful in the differential diagnosis of gallbladder diseases, especially to differentiate the wall thickening type of gallbladder carcinoma from chronic cholecystitis or adenomyomatosis, and the pseudopolypoid lesion and fundal type of adenomyomatosis from benign polyp or polypoid-type carcinoma.

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.

Contrast-enhanced ultrasonography using Sonazoid(®) is useful for diagnosis of malignant ovarian tumors: comparison with Doppler ultrasound

PURPOSE

The purpose of this study was to assess the usefulness of Sonazoid(®)-enhanced ultrasonography (US) in the diagnosis of ovarian cancer in comparison with Doppler US.

METHODS

Twenty-five ovarian tumor patients who were scheduled to undergo surgery were recruited for this study. The day before the operation, each patient was evaluated with color and power Doppler and baseline US during intravenous infusion of Sonazoid. Each lesion was classified as "benign" or "malignant" on the basis of specific criteria for a Doppler signal or Sonazoid-enhanced pattern. The reference standard was the histology of surgically removed adnexal tumors.

RESULTS

Twenty patients were diagnosed with malignant tumors (invasive cancer, n = 15; metastatic cancer, n = 1; borderline tumor, n = 4), and the remaining five were diagnosed with benign tumors. Sonazoid-enhanced US correctly depicted the presence or absence of intratumoral blood flow in all patients with an accuracy of 92 %. Color Doppler ultrasound depicted the malignancies with an accuracy of 64 %, and power Doppler ultrasound depicted them with an accuracy of 76 %.

CONCLUSION

Our study suggests that Sonazoid-enhanced US is superior to conventional color Doppler US for the diagnosis of malignant ovarian tumors, but not to power Doppler US. The data and their interpretation in our study should be taken with some degree of caution because of the small number of subjects. Further studies involving a larger sample size would be needed to confirm these findings.

Surgical resection for small hepatocellular carcinoma in cirrhosis: the Eastern experience

Detection of small Hepatocarcinoma (HCC) by screening of high-risk populations is important to increase the percentage of patients suitable for curative treatment, which would lead to prolongation of the mean survival of patients with HCC. It should be remembered that small HCC is not always necessarily equivalent to early HCC as defined histologically. With recent advances in diagnostic imaging modalities, including contrast-enhanced ultrasonography and magnetic resonance imaging with liver-specific contrast enhancement, accurate differential diagnosis of early HCCs from dysplastic nodules has become possible. Because a certain proportion of small HCCs is known to show microscopic vascular invasion, surgical resection would be the treatment of first choice. To minimize potential microscopic invasion, anatomic resection and/or resection with a wide margin should be performed, while preserving liver function to the maximum extent possible. Surgical resection, however, cannot prevent multicentric occurrence of HCC, which remains a major issue precluding curative treatment of HCC.

Utility of contrast-enhanced ultrasonography with Sonazoid in radiofrequency ablation for hepatocellular carcinoma

BACKGROUND AND AIMS

Kupffer imaging in contrast-enhanced ultrasonography (CEUS) with Sonazoid, which lasts for 60 min or longer, may be useful in ultrasound-guided percutaneous tumor ablation. The utility of Sonazoid in radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC) was investigated in this study.

METHODS

We analyzed a total of 716 HCC nodules that were detected on dynamic computed tomography in 316 patients. Detectability of these nodules was compared between CEUS and conventional ultrasonography. The effectiveness in the treatment was assessed by comparing the mean numbers of treatment sessions of RFA in patients treated with CEUS and that in historical controls matched for tumor and background conditions.

RESULTS

Detectability of tumor nodule was 83.5% in conventional ultrasonography and 93.2% in CEUS (P=0.04). Sixty-nine nodules in 52 patients were additionally detected with CEUS. The number of additionally detected tumor nodules was positively correlated with serum albumin level (P=0.016). The number of RFA sessions was 1.33±0.45 with CEUS as compared to 1.49±0.76 in the historical controls (P=0.0019).

CONCLUSIONS

CEUS with Sonazoid is useful for HCC detection in patients with a well-conserved liver function reservoir. The decrease in RFA session numbers indicated the utility of Sonazoid in RFA treatment of HCC.

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.

Differential diagnosis of hepatic tumors: value of contrast-enhanced harmonic sonography using the newly developed contrast agent, Sonazoid

OBJECTIVE

To clarify the value of contrast-enhanced harmonic ultrasonography (US) with Sonazoid, a second-generation US contrast agent, in the differential diagnosis of liver tumors compared to dynamic CT.

METHODS

A total of 249 hepatic nodules in 214 patients were studied; these included 177 hepatocellular carcinomas (HCCs), 42 liver metastases, 20 liver hemangiomas, 6 dysplastic nodules and 4 focal nodular hyperplasias (FNHs). After the injection of Sonazoid, nodules were scanned using real-time contrast-enhanced harmonic US in the vascular phases, i.e. the early and late vascular phases, and the Kupffer phase.

RESULTS

Six enhancement patterns were identified to be significant for the differential diagnosis of hepatic tumors. In HCCs, the presence of intratumoral vessels supplied from the periphery and fast washout (sensitivity, 96.6%; specificity, 94.4%) were the most typical characteristics. In metastases, the presence of rim-like enhancement with peripheral tumor vessels (sensitivity, 88.1%; specificity, 100%) was the typical pattern. In hemangiomas, the presence of intratumoral hypoperfusion images with globular or cotton wool-like pooling, which continue to the late vascular phase (sensitivity, 90.0%; specificity, 99.6%), was typical. In dysplastic nodules, the presence of portal enhancement without arterial supply in the early vascular phase and the presence of intratumoral uptake in the Kupffer phase (sensitivity, 83.3%; specificity, 100%) were the most typical patterns. In FNHs, the presence of a spoke-wheel pattern in the early vascular phase with dense staining in the late vascular phase, and positive uptake within the nodule in the Kupffer phase (sensitivity, 100%; specificity, 100%) were the most typical patterns.

CONCLUSION

Contrast-enhanced harmonic US with Sonazoid allowed intimate vascular and Kupffer imaging and, therefore, is useful for the differential diagnosis of hepatic tumors.

Carbon dioxide microbubbles-enhanced sonographically guided radiofrequency ablation: treatment of patients with local progression of hepatocellular carcinoma

PURPOSE

The aim of our study was to evaluate the usefulness of percutaneous radiofrequency ablation (RFA) using CO2 microbubbles-enhanced sonography for patients with local tumor progression of hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

The tumors of 14 patients with local progression of HCC were treated with CO2 microbubbles-enhanced RFA ablation via a catheter that had been placed in the hepatic artery. We assessed tumor detectability and technical effectiveness. The mean follow-up period was 14.1 months.

RESULTS

Only 6 of the tumors could be found on conventional sonography, whereas 14 tumors were detected on CO2 microbubbles-enhanced sonography. These 14 lesions were successfully treated with RFA guided by CO2 microbubbles-guided sonography. Technical effectiveness was complete in all patients. No serious complications were observed, and there was no local tumor progression during the follow-up period.

CONCLUSION

RFA guided by CO2 microbubbles-guided sonography is a feasible technique for treating local progression of HCC lesions that cannot be adequately depicted by conventional sonography.

Natural course of small nodular lesions with intranodular preserved portal supply in cirrhotic liver

BACKGROUND AND AIM

Due to recent advances in imaging technology, small nodules or lesions in cirrhotic liver are now seen easily. Intranodular blood supply is useful in characterizing these nodules. However, nodules with preserved portal blood supply may be malignant or benign, and it is unknown how often these nodules develop into overt hepatocellular carcinoma (HCC). This study was performed to clarify the rate of malignant transformation in such lesions with preserved portal perfusion in cirrhotic liver.

METHODS

From 1995 to 1997, in 98 patients, we performed CT during arterial portography and ultrasound angiography with intra-arterial CO2 injection for 113 nodules <3 cm in diameter to determine the intranodular blood supply. Of these, 48 nodules in 36 patients were diagnosed as 'benign nature nodules' on the basis of the blood supply of the nodules, which included arterial hypovascularity with preserved portal supply. Percutaneous biopsy of the nodule was undertaken for all nodules for histopathologic diagnosis. Thirty-two nodules in 22 patients that were not diagnosed as early HCC were followed-up clinically without any treatment to clarify the natural course of the nodules.

RESULTS

Twelve nodules in 14 patients did not increase in size and no new nodules appeared in any part of the liver. Ten nodules in 7 patients did not increase in size or arterial vascularity but typical overt HCC appeared in other areas of the liver. Only two nodules in 2 patients increased in size and developed into hypervascular overt HCC during the 15- and 34-month observation periods, respectively.

CONCLUSION

Nodules with preserved portal perfusion in cirrhotic liver have a low risk of malignant transformation compared with the surrounding liver parenchyma.

Role of parametric imaging in contrast-enhanced sonography of hepatic focal nodular hyperplasia

PURPOSE

To assess the value of parametric imaging during contrast-enhanced sonographic examination in the diagnosis of focal nodular hyperplasia (FNH) of the liver.

MATERIALS AND METHODS

Thirty-one patients with solitary FNH underwent contrast-enhanced sonographic examination between January 2003 and June 2004 using SonoVue and a Sequoia scanner equipped with Cadence Contrast Pulse Sequencing software. Contrast enhancement from a time sequence of perfusion frames was estimated using QontraXt software, which provides quantification of perfusion parameters. From the time-intensity curves, we obtained the following parameters: peak enhancement value, Tr (time recovery corresponding to time needed to reach 63% of the peak value), beta parameter corresponding to the exponential factor, and slope corresponding to the slope of the tangent to the arterial phase of enhancement.

RESULTS

Among the 4 parameters studied, the slope of the arterial phase of enhancement was the most sensitive to image the centrifugal arterial flow originating from the central portion of the lesion, whereas peak enhancement value and Tr were the most sensitive to image full enhancement of the lesion. A blinded review revealed equivalent sensitivity in the diagnosis of FNH between the interpretation of the original videoclips and that of the parametric images.

CONCLUSIONS

The results of this study show that parametric imaging can be used in place of original videoclips for clinical reporting of FNH; furthermore, it could help less-experienced sonologists diagnose FNH.

Correlation between enhancement pattern of hepatocellular carcinoma on real-time contrast-enhanced ultrasound and tumour cellular differentiation on histopathology

The objective of this study was to evaluate the correlation between the enhancement pattern of hepatocellular carcinoma (HCC) on contrast-enhanced ultrasound (CEUS) and tumour cellular differentiation on histopathology. 189 HCC lesions in 189 patients were retrospectively evaluated with CEUS and histopathological examination. CEUS was performed with SonoVue and contrast pulse sequencing. Histopathological diagnoses were made according to the Edmonson grading system. Significant differences were shown between the time that the HCC became hypoenhancing or remained echogenic in late phase and tumour cellular differentiation (p = 0.006; p = 0.036), but not with the time of commencement of hyperenhancing or commencement of isoenhancing in arterial phase and portal phase (p = 0.164, p = 0.113; p = 0.186, p = 0.070). The timing of HCC becoming hypoenhancing on CEUS is correlated with tumour cellular differentiation; well differentiated tumours wash out more slowly than poorly differentiated ones.

Differential diagnosis of nodular lesions in cirrhotic liver by post-vascular phase contrast-enhanced US with Levovist: comparison with superparamagnetic iron oxide magnetic resonance images

BACKGROUND

We investigated the diagnostic utility of post-vascular phase contrast-enhanced ultrasonography (US) and superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance imaging (MRI) as compared to the histological diagnosis of differential grades of hepatocellular carcinomas (HCCs).

METHODS

Forty-nine patients with histologically characterized liver nodules (well-differentiated HCC, n = 20; moderately differentiated HCC, n = 19; poorly differentiated HCC, n = 1; dysplastic nodule, n = 9) received contrast-enhanced US and SPIO-MRI. Subsequently, we quantitatively evaluated the relationships between the images of the nodules and their histological diagnosis and differential grades.

RESULTS

The ratio of the echogenicity of the tumorous area to that of the nontumorous area with post-vascular phase contrast-enhanced US (post-vascular phase ratio) decreased as nodules became less differentiated (P < 0.05; Kruskal-Wallis test). The ratio of the intensity of the nontumorous area to that of the tumorous area on SPIO-enhanced MR images (SPIO intensity index) also decreased as nodules became less differentiated (P < 0.01). The post-vascular phase ratio correlated with the SPIO intensity index for HCCs and dysplastic nodules (r = 0.76). The conformity of the result from the post-vascular phase contrast-enhanced US and SPIO-MRI was 96%.

CONCLUSIONS

Contrast-enhanced US is a valuable method for predicting the histological grade of HCCs in cirrhotic patients, and may be a good alternative to SPIO-enhanced MRI.

Comparison of IV Contrast-Enhanced Sonography and Histopathology of Pancreatic Cancer

OBJECTIVE

We compared contrast-enhanced sonography findings with pathologic findings in pancreatic cancer to evaluate the ability of contrast-enhanced sonography to depict the pathologic changes associated with pancreatic cancer.

SUBJECTS AND METHODS

Thirty-four patients with pancreatic cancer who underwent surgery were investigated. Sonography was performed with contrast material (Levovist) for all patients before surgery. Pathologic findings were evaluated on the basis of the resected cancer specimens. We compared contrast-enhanced sonography findings with pathologic findings.

RESULTS

All tumors that were hyperechoic on contrast-enhanced sonography were papillary adenocarcinoma, and all tumors that were hypoechoic on contrast-enhanced sonography were ductal adenocarcinoma. Among ductal adenocarcinomas, five (71.4%) of seven tumors for which the size of the hypoechoic area was unchanged on contrast-enhanced sonography had clear tumor margins with no infiltration or inflammation in the margin. In contrast, all tumors for which the size of the hypoechoic area was reduced on contrast-enhanced sonography had unclear tumor margins with infiltration of cancerous cells and inflammation. Nine (90%) of 10 tumors that showed partial contrast enhancement or a vascular shadow in a hypoechoic area had large or medium-sized vessels within a tumor at pathology. In contrast, only one (4.8%) of 21 tumors that did not show the vascular shadow in a hypoechoic area had no large or medium-sized vessels in a tumor.

CONCLUSION

Contrast-enhanced sonography well reflects the pathologic changes of pancreatic cancer and will provide useful information in a pretreatment evaluation. Further studies with a large number of patients will be required to confirm this finding.

Early Detection and Characterization of Hepatocellular Carcinoma: Value of Imaging Multistep Human Hepatocarcinogenesis

The method for early detection of hepatocellular carcinoma (HCC) has been well established in Japan, by means of regularly screening patients at risk for developing HCC by imaging and serological markers of tumor. The principal screening protocol includes performing ultrasonography (US) every 3 months and testing for tumor markers every month in patients at high risk for HCC. There has been another important issue of accurate characterization of nodular lesions found in cirrhotic liver. This problem has been solved by the development of imaging modalities such as US angiography with intra-arterial injection of CO(2), computed tomography during hepatic arteriography and computed tomography during arterial portography. It is most important to differentiate the typical hemodynamic patterns of a low-grade dysplastic nodule having arterial hypovascularity with portal perfusion preserved from those of HCC characterized by arterial hypervascularity with decreased portal perfusion. At present, these findings are easily obtained by contrast-enhanced phase invasion harmonic imaging, which is a noninvasive US technology.

Multiple hypervascular liver nodules in a heavy drinker of alcohol

A case of hypervascular nodules in the liver, but without hepatitis B or C virus infection in a 38-year-old woman with a history of alcohol abuse is presented. An ultrasound disclosed 1-2-cm hypoechoic tumors in the right and left lobes. Magnetic resonance imaging showed high-intensity tumors at both the T1-weighted and T2-weighted sequences. Incremental dynamic computed tomography and hepatic angiography revealed hypervascular tumors. Ultrasound-guided needle biopsy revealed no evidence of hepatocellular carcinoma, metastatic liver cancer, hemangioendothelioma, inflammatory pseudotumors or pseudolymphoma, but demonstrated stellate-scar fibrosis septa, which contained small unpaired arteries without hyperplasia dividing the nodule. Moreover, marked pericellular fibrosis, neutrophilic infiltration and Mallory bodies were observed in the cytoplasm. There was no evidence of bile duct proliferation. From these findings, the diagnosis of alcohol-induced fibrosis, distinctly different from focal nodular hyperplasia, was tenable. Further studies may provide insights into the pathogenesis of nodule formation and hypervascularity in heavy drinkers of alcohol.

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.

Assessment of tumor hemodynamics in small hepatocellular carcinoma: comparison of Doppler ultrasonography, angiography-assisted computed tomography, and pathological findings

AIM

We evaluated the usefulness of Doppler ultrasonography (DUS) for the analysis of tumor hemodynamics in small hepatocellular carcinoma (HCC).

METHODS

We compared Doppler ultrasound (DUS) findings with angiography-assisted computed tomography (Angio-CT) such as CT during arterial portography and during hepatic arteriography in the evaluation of the intratumoral hemodynamics, and with pathologic findings in 45 small HCC nodules (< or =3.0 cm in diameter) of 43 patients. DUS flow pattern of each nodule was categorized into three types: afferent continuous flow (Type 1), afferent pulsatile flow with afferent continuous flow (Type 2), and afferent pulsatile flow without afferent continuous flow (Type 3). Intratumoral blood supply was determined by Angio-CT, and pathologic findings were evaluated on resected or biopsied specimen.

RESULTS

Based on Angio-CT findings, Type 1 nodules showed decreased arterial blood supply (ABS) without decreased portal blood supply (PBS). Type 2 nodules showed unchanged ABS but decreased PBS. Type 3 nodules showed both increased ABS and decreased PBS. DUS findings well represented blood supply of HCC evaluated by Angio-CT. In addition, all Type 1 and 2 nodules were well-differentiated HCC, and all Type 3 nodules were moderately or poorly differentiated HCC; DUS findings well reflected differentiation of HCC.

CONCLUSIONS

DUS is a non-invasive imaging method and can be used for the evaluation of the stage of malignancy of small HCC.

Characterization of hepatic tumors: value of contrast-enhanced coded phase-inversion harmonic angio

OBJECTIVE

Our purpose was to evaluate the value of contrast-enhanced coded phase-inversion harmonic imaging in showing the characteristic intranodular hemodynamics of hepatic tumors. SUBJECTS AND METHODS. Using a microbubble contrast agent we performed coded harmonic angio in 163 patients with 192 hepatic tumor nodules: 153 hepatocellular carcinomas, 13 metastases, 14 hemangiomas, eight dysplastic nodules, and four focal nodular hyperplasias. After injecting Levovist, we performed real-time scanning, interval-delay fast low-angle shot imaging, and sweep scanning in the early arterial phase, late vascular phase, and postvascular phase, respectively.

RESULTS

On contrast-enhanced coded harmonic angio, the typical hemodynamic pattern of hepatocellular carcinomas was shown as abundant tumor vessels supplied from the periphery to the center of the tumor and dense parenchymal tumor staining with fast washout (sensitivity, 92.8%; specificity, 92.3%). The characteristic hemodynamic pattern of metastases was peripheral tumor vessels with a rim parenchymal stain in the vascular phase followed by a perfusion defect in the postvascular phase (sensitivity, 69.2%; specificity, 100%). Hemangiomas were hypovascular in the early arterial phase with gradual spotty or cotton-wool pooling continuing to the late vascular phase (sensitivity, 92.9%; specificity, 100%). Dysplastic nodules were shown as having no early arterial supply with isovascularity in the late vascular phase (sensitivity, 75%; specificity, 100%). Focal nodular hyperplasias were shown to have a spoked wheel pattern of blood vessels accompanied by dense staining in interval-delay scanning (sensitivity, 100%; specificity, 100%).

CONCLUSION

Contrast-enhanced coded harmonic angio is a promising method to provide useful information for the differential diagnosis of hepatic tumors.

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.

Progression to hypervascular hepatocellular carcinoma: correlation with intranodular blood supply evaluated with CT during intraarterial injection of contrast material

PURPOSE

To analyze the correlation between intranodular blood supply of borderline lesions (ie, dysplastic nodules or hypovascular well-differentiated hepatocellular carcinoma [HCC] nodules) and their progression to hypervascular classic HCC in cirrhotic livers.

MATERIALS AND METHODS

One hundred seventy-six borderline lesions seen at computed tomography (CT) during arterial portography (CTAP) and CT during hepatic arteriography (CTHA) were evaluated in 49 patients with cirrhosis who underwent repeated CTAP and/or CTHA but no therapy. On the basis of CTAP findings, nodules were categorized as group A (showing almost the same portal venous supply as the surrounding liver), group B (showing decreased portal venous supply) or group C (showing partially absent portal venous supply); on the basis of CTHA findings, nodules were categorized as group I (showing almost the same arterial supply as the liver), group II (showing decreased arterial supply), or group III (showing partially increased arterial supply).

RESULTS

Progression to classic HCC was observed in 29.4% of group A nodules, 53.9% of group B nodules, and 87.9% of group C nodules within 1,000 days; in 58.6% of group I nodules, 12.9% of group II nodules, and 92.2% of group III nodules within 730 days; and in 0% of nodules in group A and I, 28% of nodules in group B and/or II, and 88.7% of nodules in group C and/or III within 730 days.

CONCLUSION

Evaluation of intranodular blood supply was valuable in predicting the prognosis in borderline lesions, except when only arterial blood supply was evaluated.

Multi-centre clinical study evaluating the efficacy of SonoVue (BR1), a new ultrasound contrast agent in Doppler investigation of focal hepatic lesions

OBJECTIVES

SonoVue is a new ultrasound contrast agent, which consists of stabilised microbubbles of a sulphur hexafluoride gas. The aim of the study was to assess its efficacy in the Doppler investigation of focal hepatic lesions.

MATERIALS AND METHODS

Seventy patients with focal liver tumours were studied. Four doses (0.3, 0.6, 1.2 and 2.4 ml) of SonoVue were administered intravenously with at least 10 min delay between each injection. A complete colour/power and spectral Doppler imaging investigation of the lesions was performed at baseline pre-dosing and after each SonoVue injection. All examinations were recorded on SVHS videotapes. Baseline and post contrast videotapes were reviewed by the on-site (un-blinded) investigators and by two off-site blinded readers (a) to grade the global quality of the Doppler scans of the focal lesions vascularity and the normal parenchymal vessels (b) to measure the duration of clinically useful Doppler signal enhancement and (c) to determine the diagnostic accuracy and performance of the enhanced versus unenhanced scans using histopathology, tumour markers, CT and/or MR as the reference standard.

RESULTS

A statistically significant improvement was observed at all four SonoVue doses in the off site assessment of global quality of the Doppler examination of tumoral and normal parenchymal vessels in comparison with the baseline (P < 0.05). The median duration of clinically useful enhancement was significantly increased with increasing doses (P < 0.001), ranging between 1.4-2.2 min for the lowest dose and 3.2-3.8 min for the highest dose for the off-site readers. On-site assessment of diagnostic accuracy showed a significant increase in the specificity of the Doppler diagnoses (P < 0.0016) with an increase in the positive and negative predictive values and in the likelihood ratio in differentiating between benign and malignant lesions. Off-site evaluation showed a significant increase in the accuracy of enhanced Doppler diagnosis in comparison with the baseline performance.

CONCLUSION

The results suggest that SonoVue is effective in improving the display of tumoral vascularisation and may be useful in the characterisation of focal liver lesions.

Assessment of vascularity in hepatic tumors: comparison of power Doppler sonography and intraarterial CO(2)-enhanced sonography

OBJECTIVE

The purpose of the study was to compare power Doppler sonography with intraarterial CO(2)-enhanced sonography for revealing vascularity in treated and untreated hepatic tumors.

SUBJECTS AND METHODS

Fifty-five patients with 93 liver tumors were prospectively examined with power Doppler sonography and CO(2)-enhanced sonography. These tumors included 29 hepatocellular carcinomas in patients with no previous treatment, 26 treated hepatocellular carcinomas, and 38 hemangiomas. The vascular depiction of power Doppler sonography was compared with that obtained in the early phase of CO(2)-enhanced sonography. The results of angiography were also recorded for comparison.

RESULTS

In the hepatocellular carcinomas, power Doppler sonography was the same as CO(2)-enhanced sonography in 18 (62%) of 29 tumors, was inferior to CO(2)-enhanced sonography in nine (31%) of 29 tumors, and was superior to CO(2)-enhanced sonography in two (7%) of 29 tumors. In the treated hepatocellular carcinomas, power Doppler sonography was the same as CO(2)-enhanced sonography in 15 (58%) of 26 tumors and was inferior in 11 (42%) of 26 tumors. In hemangiomas, the same vascularity was found in both studies in 15 (39%) of 38 tumors, CO(2)-enhanced sonography was superior in 22 (58%) of 38 tumors, and power Doppler sonography was superior in one (3%) of 38 tumors. As a whole, 45% of the 93 tumors showed better vascular depiction on CO(2)-enhanced sonography. However, 19.4% of tumors were hypovascular using power Doppler sonography but hypervascular using CO(2)-enhanced sonography.

CONCLUSION

Power Doppler sonography is a useful technique for screening hepatic tumor vascularity. CO(2)-enhanced sonography is superior to power Doppler sonography in depicting tumor vascularity in treated hepatocellular carcinomas and in hemangiomas, especially small hemangiomas.

Depiction of vasculature in small hepatocellular carcinoma, and dysplastic nodules evaluated with carbon dioxide ultrasonography and angiography

PURPOSE

To evaluate the vascularity in dysplastic nodules and well-differentiated and moderately to poorly differentiated hepatocellular carcinomas (HCCs) less than 2 cm using carbon-dioxide (CO2) US and angiography.

MATERIAL AND METHODS

A total of 115 pathologically proven small liver tumors (0.7 approximately 2.0 cm) were included in the study. There were 31 dysplastic nodules, 49 well-differentiated HCCs and 35 moderately to poorly differentiated HCCs. A comparative study of angiography and CO2 US was carried out.

RESULTS

Of the dysplastic nodules, 28 out of 31 tumors were hypo- or isovascular at CO2 US. Twenty-seven out of 31 tumors were hypovascular at angiography. Of the well-differentiated HCCs, 38/49 showed hypervascularity at CO2 US while 24/49 tumors were hypervascular at angiography. All moderately to poorly differentiated HCCs showed hypervascularity at CO2 US, compared to 30/35 tumors at angiography.

CONCLUSION

Most of the dysplastic nodules were hypovascular and most of the moderately to poorly differentiated HCCs were hypervascular. The vascularity of well-differentiated HCCs was in between the above tumors. Both CO2 US and angiography were equally effective in demonstrating the vascularities in dysplastic nodules and moderately to poorly differentiated HCCs. CO2 US was significantly superior to angiography when identifying the vascularity in well-differentiated HCCs.

Nonresectable hepatocellular carcinoma: improved percutaneous ethanol injection therapy guided by CO(2)-enhanced sonography

OBJECTIVE

The purpose of our study was to evaluate the usefulness of percutaneous ethanol installation using CO(2)-enhanced sonography for patients with nonresectable hepatocellular carcinoma (HCC).

SUBJECTS AND METHODS

Forty-six patients with 65 HCC lesions were examined with contrast-enhanced sonography with direct injection of CO(2) into the proper hepatic artery during arteriography. We performed percutaneous ethanol injection guided by CO(2)-enhanced sonography for the treatment of hypervascular HCC lesions that could not be treated with conventional percutaneous ethanol injection or with transcatheter arterial embolization.

RESULTS

CO(2)-enhanced sonography detected five additional small HCC lesions before treatment (p<0.05) and 14 new lesions during follow-up (p<0.01), than conventional sonography detected. CO(2)-enhanced sonography showed positive enhancement of residual lesions after initial treatment (n = 3) and incomplete local treatment (n = 5) that were not detected on conventional sonography. These 27 lesions were successfully treated with percutaneous ethanol injection using a mixture of iodized oil and ethanol and guided by CO(2)-enhanced sonography.

CONCLUSION

CO(2)-enhanced sonography is a sensitive method for detecting residual viable lesions and small new HCC lesions that cannot be detected with conventional sonography. Percutaneous ethanol injection guided by CO(2)-enhanced sonography can treat hypervascular HCC lesions that cannot be treated with conventional percutaneous ethanol injection or transcatheter arterial embolization.

Hepatocellular carcinoma: depiction of tumor parenchymal flow with intermittent harmonic power Doppler US during the early arterial phase in dual-display mode

PURPOSE

To assess the effectiveness of contrast material-enhanced intermittent harmonic Doppler ultrasonography (US) in depicting tumor vessels and tumor parenchymal flow (stain) in hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

Fifty-eight patients with 65 HCC nodules were examined by using intermittent harmonic power Doppler US and digital subtraction harmonic B-mode US, both with intravenous administration of SH U 508A. Vascular findings at early arterial phase harmonic US were classified as positive enhancement or nonenhancement, depending on the tumor vascularity relative to the surrounding liver parenchyma. These results were compared with those of three-phase helical dynamic computed tomography (CT).

RESULTS

For hypervascular HCCs, there was excellent depiction of tumor vessels and tumor stain with the two intermittent harmonic US methods. The sensitivity and specificity for depiction of tumor vascularity were 93% (41 of 44 nodules) and 100% (21 of 21), respectively, with intermittent harmonic power Doppler US and 86% (38 of 44) and 100% (21 of 21), respectively, with subtraction US, as compared with these values at dynamic CT. Attenuation was an important factor in the depictability of tumor vascularity at harmonic US.

CONCLUSION

Contrast-enhanced intermittent harmonic US enables noninvasive demonstration of tumor vessels and especially tumor stain in HCC.

Power Doppler sonography of hepatocellular carcinomas with portal-vein blood supply

We report the power Doppler imaging (PDI) findings in 2 cases of hepatocellular carcinoma (HCC) with a portal-vein blood supply. Gray-scale sonography in both cases showed a well-circumscribed nodule, hypoechoic in case 1 and hyperechoic in case 2. PDI revealed an afferent tumor vessel with constant flow in both nodules, and CT during arterial portography demonstrated a portal-vein supply to both nodules. The nodules were diagnosed by percutaneous core biopsies as highly differentiated HCC. We also examined with PDI another 64 patients with 76 HCC nodules, and none of the nodules showed a constant-flow afferent tumor vessel. The presence of a constant-flow afferent tumor vessel indicates a supplying portal vein; but this is not diagnostic of HCC, and biopsy remains necessary to establish a final diagnosis.

Ultrasound contrast harmonic imaging of abdominal organs

Ultrasound contrast agents consist of microbubbles, which are the most effective acoustic backscatters. The interaction between the insonating ultrasound beam and the microbubbles is very complex and basic understanding of their behavior under various sound fields has been fundamental to the development of improved methods of visualizing and displaying the contrast agents. Although echo enhancers have been under development for a long time, their clinical applications have been limited to enhancing the Doppler signals in difficult cases. However, recent advances in harmonic imaging and the development of new tissue-specific contrast agents stand to broaden the scope of ultrasound diagnostic potential beyond simply rescuing failed Doppler examinations. This article reviews the current and potential applications of ultrasound contrast harmonic imaging in the abdomen.

Hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is increasing in many countries as a result of an increase in hepatitis C virus (HCV) infection since World War II. The epidemiology of HCC varies with the global region. There have been conflicting observations from different parts of the world concerning the frequency of HCC in patients who in the distant past had post-transfusion non-A, non-B hepatitis. The genetic basis of hepatocarcinogenesis is still poorly understood. In hepatitis B virus (HVB) associated HCC, codon 249 mutation in the p 53 gene seems more related to exposure to aflatoxin B1 than to hepatocarcinogenesis itself. HCC that occurs in children in high HBV endemic regions could be associated with germ-line mutations, but little information is available; not much is known about chemical hepatocarcinogens in the environment other than aflatoxins. The X gene of HBV seems to play an important role in HBV-associated hepatocarcinogenesis. There are preliminary observations on the molecular mechanism of HCV-associated HCC, such as HCV core protein inducing HCC in transgenic mice and the NS3 genome transforming NIH 3T3 cells. Pathological distinction between preneoplastic and very early transformed lesions still depends on classical morphology, and a more genetically oriented differential diagnosis is required. Clinical diagnosis based on modern imaging has improved greatly, but is still unsatisfactory in the differential diagnosis of preneoplastic and early transformed nodules, because the vasculature changes that occur within the nodule are not accurately discerned with the current imaging. Use of sensitive des-gamma-carboxy prothrombin (PIVKA II) assay, and lectin affinity chromatography separating HCC specific subspecies of AFP molecules with a more practical biochemical technique will further improve diagnosis. Early diagnosis and transplantation are the best treatment at the moment, but transplantation is not widely available because of the donor shortage. Despite successful resection, the remnant cirrhotic liver frequently develops new HCC lesions, seriously curtailing long-term survival. All-out efforts should be directed to the prevention of HCC, through prevention of viral hepatitis, prevention of acute hepatitis from becoming chronic, prevention of chronic hepatitis from progressing to cirrhosis, and prevention of the cirrhotic liver from developing HCC (chemoprevention). At the moment, very few such studies exist.

Early experience in the use of Levovist ultrasound contrast in the evaluation of liver masses

The aim of the present paper was to assess the utility of Levovist in defining the pathology of liver masses. Levovist is a new ultrasound contrast agent consisting of galactose microparticles, air bubbles and palmitic acid. Prospective studies were performed in patients referred for further evaluation of known liver masses. Levovist was peripherally injected and colour Doppler ultrasound studies were performed. Findings were correlated with clinicopathology and three other imaging modalities: biphasic spiral CT, CT arterial portography and contrast MRI. Twenty-five patients were studied (15 male and 10 female) in the age range 25-74 years. Liver masses ranged from 0.5 to 7 cm in maximum diameter. Thirteen lesions were benign and 12 were malignant (four hepatomas (HCC) and eight metastases). Levovist enhancement occurred in 18 lesions. Of these, six were benign (four focal nodular hyperplasias (FNH) and two haemangiomas). All 12 malignant lesions demonstrated enhancement. The HCC showed a mosaic pattern of central and peripheral enhancement, and the FNH demonstrated a spoke-wheel pattern. It was not possible to distinguish between haemangiomas and malignant lesions. Non-enhancing lesions may well be benign, with all malignancies showing some enhancement. Characteristic enhancement patterns were found for HCC (mosaic) and FNH (spoke-wheel). It was not possible to distinguish between metastases and benign lesions (haemangiomas) when the pattern of enhancement was peripheral.

Clinical evaluation of contrast-enhanced color Doppler sonography in the differential diagnosis of liver tumors

PURPOSE

We investigated the value of contrast-enhanced color Doppler sonography in the differential diagnosis of liver tumors.

METHODS

We prospectively examined 105 focal liver lesions in 100 patients by real-time gray-scale sonography, color Doppler sonography, and contrast-enhanced color Doppler sonography with galactose-based microbubbles (SH U 508A; Levovist). The final diagnoses of the liver lesions as confirmed by pathology or additional imaging techniques were 31 metastases, 25 hemangiomas, 19 hepatocellular carcinomas, 19 focal nodular hyperplasias, 2 cholangiocellular carcinomas, and 9 other lesions.

RESULTS

Vascularity could be detected in 43 (41%) of the 105 lesions by conventional color Doppler sonography compared to 67 (64%) by contrast-enhanced color Doppler sonography. Contrast-enhanced color Doppler sonography identified moderate or extensive vascularity in all 19 focal nodular hyperplasias, moderate or extensive vascularity in 16 hepatocellular carcinomas and both cholangiocellular carcinomas, and no or minor vascularity in all but 3 hemangioma. The combination of gray-scale, conventional color Doppler, and contrast-enhanced color Doppler sonography led to the correct diagnosis in 81% of cases (85 of 105), compared to 57% (60/105) for gray-scale and conventional color Doppler sonography and 31% (33/105) for gray-scale sonography alone.

CONCLUSIONS

Contrast-enhanced color Doppler sonography improves the detection of tumor vascularity and is useful in the differential diagnosis of liver lesions.

Usefulness of measurement of Lens culinaris agglutinin-reactive fraction of alpha-fetoprotein as a marker of prognosis and recurrence of small hepatocellular carcinoma

OBJECTIVE

Lens culinaris agglutinin-reactive fraction of alpha-fetoprotein (AFP-L3%) is a recently described marker of hepatocellular carcinoma (HCC), and its usefulness has been demonstrated in many studies. We evaluated the usefulness of serial measurement of AFP-L3% as a marker of prognosis and recurrence after treatment of small HCC.

METHODS

AFP-L3% was measured before and after initial treatment in 60 patients with small HCC (maximum diameter < or = 2 cm). AFP-L3% was taken as the ratio of AFP-L3 to total AFP and multiplied by 100%, and levels > or = 10% were considered positive. Outcomes and recurrence were compared between patients AFP-L3%-negative after initial treatment (Group A, n = 43) and patients who were AFP-L3%-positive after initial treatment (Group B, n = 17).

RESULTS

Before treatment, AFP-L3% was positive in 14 (23.3%) of the 60 patients. The cumulative survival rate of Group A was significantly longer (p = 0.0091) than that of Group B. The recurrence rate was significantly higher in Group B (p = 0.0104) than in Group A. When recurrence was limited to intrahepatic metastasis, the recurrence rate was significantly higher in Group B (p = 0.0064). However, the recurrence rate of multicentric occurrence did not differ significantly between Groups A and B.

CONCLUSIONS

Measurement of AFP-L3% after treatment may be useful for understanding prognosis and recurrence of HCC.

Inflammatory pseudotumor of the liver in a patient with chronic hepatitis C: difficulty in differentiating it from hepatocellular carcinoma

A case of an inflammatory pseudotumor of the liver in a 75-year-old female with chronic hepatitis C whose radiologic features simulated that of hepatocellular carcinoma (HCC) is presented. On imaging studies, hypervascularity by CO2 ultrasound (US) angiography, enhancement at an early phase and isodensity at a late phase by incremental dynamic computed tomography (CT), perfusion defect by CT during arteriography (CTAP), and clinical background of hepatitis C virus (HCV) infection strongly suggested HCC. A US-guided needle biopsy revealed a mainly diffuse and polyclonal proliferation of lymphocytes positive for leukocyte common antigen (pan-lymphocyte cells), L-26 (B cell lymphocytes), and UCHL-1 (T cell lymphocytes), negative for both kappa and lambda light chains and sparsely distributed neutrophils and histiocytes. No lymphoid follicles were observed. The liver tissue around this tumor showed chronic hepatitis with mild activity and mild fibrosis. These histopathologic findings suggested that the diagnosis of inflammatory pseudotumor of the liver was tenable. As it is difficult to differentiate between inflammatory pseudotumor of the liver and HCC by imaging studies alone, supplemental biopsy, where possible, should be obtained when diagnostic imaging of tumors suggesting HCC is carried out. We emphasize that histopathology is a true gold standard in the diagnosis of this disease.

Detection of hepatocellular carcinoma: comparison of T2-weighted breath-hold fast spin-echo sequences and high-resolution dynamic MR imaging with a phased-array body coil

The purpose of our study was to compare T2-weighted breath-hold fast spin-echo sequence (BHFSE) and high-resolution dynamic MR imaging (HR-DMRI) in the detection of hepatocellular carcinoma (HCC). Short and long T2-weighted BHFSE sequences and biphasic HR-DMRI including arterial-dominant and delayed phase images with a phased-array body coil were performed in 30 consecutive patients with 37 HCCs. The lesion-to-liver contrast-to-noise ratio (CNR) was quantitatively measured. The lesion conspicuity and delineation was qualitatively rated according to a four-point scale. The lesion-to-liver CNR was highest with the arterial-dominant phase HR-DMRI and was significantly higher than those obtained with both short and long T2-weighted BHFSE and those obtained with unenhanced and delayed HR-DMRI. The CNR obtained with short T2-weighted BHFSE was significantly higher than those obtained with long T2-weighted BHFSE and with unenhanced and delayed HR-DMRI. The sensitivity for the sequences was 78.4% (29/37) for short T2-weighted BHFSE, 67.6% (25/37) for long T2-weighted BHFSE, 37.8% (14/37) for unenhanced HR-DMRI, 97.3% (36/37) for arterial-dominant phase HR-DMRI, and 43.2% (16/37) for delayed HR-DMRI. The sensitivity of serial dynamic MR imaging combined with unenhanced, arterial-dominant phase imaging and delayed phase imaging was 100% (37/37). The score in the qualitative analysis of the lesion conspicuity and delineation was highest for the arterial-dominant phase HR-DMRI and was significantly higher than that for the short T2-weighted BHFSE. The score for the short T2-weighted BHFSE was significantly higher than that for the long T2-weighted BHFSE and that for the unenhanced HR-DMRI. Arterial-dominant phase HR-DMRI is superior to the T2-weighted BHFSE technique, and also HR-DMRI combined with unenhanced, arterial-dominant and delayed phases is the most sensitive technique in the detection of HCC.

Clinical utility of Lens culinaris agglutinin-reactive alpha-fetoprotein in small hepatocellular carcinoma: special reference to imaging diagnosis

BACKGROUND/AIMS

Blood concentration levels of alpha-fetoprotein like the Lens culinaris agglutinin-reactive fraction (AFP-L3) are a useful marker for predicting the long-term prognosis of hepatocellular carcinoma. This study investigated the relationship between serum AFP-L3 and various imaging modalities.

METHODS

Sixty-three patients with small hepatocellular carcinomas < or = 2 cm in diameter were studied. Serum AFP-L3 concentrations were measured by lectin-affinity electrophoresis coupled with antibody-affinity blotting and expressed as % AFP-L3 (the percent of AFP-L3 as total AFP). A clinical "cutoff level" of 10% was used in this study to indicate the presence of hepatocellular carcinoma. Selective hepatic intraarterial digital subtraction angiography (DSA), ultrasonographic angiography with carbon dioxide microbubbles (USAG), and computed tomography during arterial portography (CTAP) were performed to evaluate the hemodynamics of hepatic nodules.

RESULTS

Fourteen (22.2%) of the 63 patients were positive for % AFP-L3. The % AFP-L3 levels (n=45, 4.4%) of patients with hypervascular tumors were significantly higher than those (n=15, 0.0%) of patients with isovascular or hypovascular tumors as determined by USAG (p=0.0061). The % AFP-L3 levels (n=53, 4.4%) of patients with a negative portal blood supply were significantly higher than the % AFP-L3 levels (n=7, 0.0%) of patients with a positive portal blood supply as determined by CTAP (p=0.0140). The % AFP-L3 levels of patients with tumors with a long doubling time (DT) were significantly lower than for patients with tumors with a short DT (p=0.0176).

CONCLUSION

AFP-L3 is a positive indicator which may be more specific for small advanced hepatocellular carcinoma.

A case of progressive multiple focal nodular hyperplasia with alteration of imaging studies

Focal nodular hyperplasia (FNH) of the liver is a lesion characterized by a well circumscribed region of hyperplastic liver tissue with stellate fibrosis. The pathogenesis of the lesion is unknown but various authors consider that FNH may be a response to a preexisting vascular abnormality. We experienced a case of progressive multiple FNH, in which the hemodynamic change as shown by imaging modalities, may support this hypothesis. The patient, a 38-yr-old woman, was found by chance to have multiple portal venous shunts and multiple FNH in both lobes of her liver. Because of their benign characteristics, we followed the nodules periodically without any special treatment. After about 4 yr, the nodules increased both in size and number. In addition, digital subtraction angiography showed that the diameter of the artery had become larger. The hemodynamic change revealed by imaging studies in this case supports the hypothesis that one of the pathogens of FNH is a secondary hepatocellular response to arterial hyperperfusion caused by some vascular malformations.

Carbon dioxide enhanced ultrasonography of hepatic haemangiomas

The purpose of this study was to characterize the imaging manifestations of carbon dioxide enhanced ultrasonography (CO2US) in hepatic haemangiomas. CO2US was performed for 52 haemangiomas in 25 patients and for 352 various hepatic nodules in 192 patients. Characteristic enhancement patterns for hepatic haemangiomas were noted. All 39 large haemangiomas (> 1 cm) demonstrated peripheral nodular enhancement in the early and parenchymal phases associated with delayed washout character (> 30 min). Centripetal fill-in of CO2 was noted in 82.1% of large haemangiomas. Two enhancing patterns were noted in 13 small haemangiomas (< 1 cm): peripheral nodular (69.2%) and homogeneous (30.8%). Delayed washout was also noted in all small haemangiomas. Centripetal fill-in of CO2 was hard to define in small haemangiomas. None of the other 352 hepatic nodules had the same imaging features. In conclusion we found that CO2US is valuable in differentiating hepatic haemangiomas from other liver tumours in clinically doubtful cases.