Hirokazu Onda

Detection of tumor parenchymal blood flow in hepatic tumors : value of second harmonic imaging with a galactose-based contrast agent

Purpose. To evaluate the detectability of tumor vascularity in hepatic tumors by second harmonic imaging with the administration of a microbubble contrast agent, Levovist. Materials and methods: Twenty-four patients with hepatic tumors (21 hepatocellular carcinoma, one focal nodular hyperplasia and two liver metastasis) were studied using Aloka SSD 5500 with the administration of Levovist. Intermittent harmonic gray-scale imaging (HGSI) and intermittent harmonic power Doppler imaging (HPDI) were performed on every tumor and the detectability of the two harmonic imaging modes were compared with that of dynamic CT. Results: Tumor vessels and tumor parenchymal blood flow were obtained in hypervascular tumors in the early arterial phase, and metastasis presented peripheral enhancement. When dynamic CT was taken as a gold standard, the sensitivity, specificity and accuracy of detecting tumor vascularity for intermittent HGSI were 55.6, 100 and 66.7%, and for intermittent HPDI were 83.3, 100 and 87.5%, respectively. The difference of detectability between the two modes was statistically significant (P<0.05). Depth of the lesion from the abdominal wall was a major factor affecting the detectability of tumor vascularity. Conclusion: With the administration of Levovist, intermittent HPDI was more sensitive than intermittent HGSI to demonstrate tumor vessels and tumor blood flow. Second harmonic imaging with Levovist would be a promising valuable means for investigating specific vascular features in hepatic tumors.

Contrast advanced dynamic flow imaging and contrast pulse subtraction imaging: Preliminary results in hepatic tumors

PurposeTo investigate the usefulness of contrast advanced dynamic flow imaging and contrast pulse subtraction imaging in the intranodular hemodynamics of hepatic tumors.Materials and MethodsTen patients underwent contrast advanced dynamic flow imaging and contrast pulse subtraction imaging using Levovist®, a microbubble contrast agent. Fourteen hepatic tumor nodules were studied: 9 were hepatocellular carcinoma, 1 metastasis, 1 hemangioma, 1 adenomatous hyperplasia, and 2 metastatic lymph nodes of hepatocellular carcinoma. Real-time scanning of contrast advanced dynamic flow imaging and intermittent interval-delay scanning of contrast pulse subtraction imaging were carried out in the early arterial phase, the late vascular phase, and the postvascular phase. The results obtained from contrast advanced dynamic flow imaging and contrast pulse subtraction imaging were compared with those obtained by precontrast power Doppler imaging and three-phase dynamic CT, respectively.ResultsThe rate of detection of intranodular vascularity by contrast advanced dynamic flow imaging (93%) or contrast pulse subtraction imaging (93%) was significantly higher than that of precontrast power Doppler imaging (29%) and was as high as that of dynamic CT. Characteristic intranodular hemodynamics were detected in hepatocellular carcinoma, metastasis, hemangioma, and adenomatous hyperplasia with typical appearance of an intranodular blood vessel image in the early arterial phase, a parenchymal stain image in the late vascular phase, and a perfusion defect image in the post-vascular phase.ConclusionContrast advanced dynamic flow imaging and contrast pulse subtraction imaging clearly show the intranodular hemodynamics in hepatic tumors.

Hepatocellular carcinoma associated with secondary haemochromatosis in non-cirrhotic liver: a case report.

We describe one case of hepatocellular carcinoma (HCC) arising in secondary haemochromatosis in a non-cirrhotic liver. The patient was a 40-year-old male. He had severe pancytopenia due to myelodysplastic syndrome (MDS) and developed secondary haemochromatosis as a result of a large amount of erythrocyte transfusion. Multiple nodules of the liver appeared about 6 years after the diagnosis of MDS. Needle biopsy of the nodules histologically confirmed them to be moderately differentiated HCCs. The liver parenchyma was shown to be non-cirrhotic and a deposit of hemosiderin was also identified, consistent with a finding of haemochromatosis of the liver. Transarterial chemoembolization was performed to treat multiple HCCs. There are a number of reports describing HCC occurrence in non-cirrhotic patients with hereditary haemochromatosis. However, HCC in secondary haemochromatosis without cirrhosis is extremely rare.

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.

Intrahepatic huge hematoma due to rupture of small hepatocellular adenoma: a case report.

Hepatocellular adenoma sometimes causes intraperitoneal hemorrhage. It is, however, rare for small hepatocellular adenoma to cause intrahepatic huge hemorrhage without intraperitoneal bleeding. Here we describe such a rare case of hepatocellular adenoma with huge intrahepatic hemorrhage in a 25-year-old female, who had taken oral contraceptives for the last 2 weeks. She was admitted to our hospital with a sudden onset of right-upper-quadrant abdominal pain and temporally fell in shock state. Plain CT depicted low density area measuring more than 13 cm in diameter in the right lobe of the liver. Huge tumor was also suggested by abdominal ultrasound, contrast enhanced CT, magnetic resonance imaging (MRI) and angiography. The patient was diagnosed as intrahepatic rupture of hepatic tumor. Because of the risk of re-hemorrhage and malignancy, she underwent right hepatic lobectomy. Histopathologial examination of the resected specimen showed a typical small hepatocellular adenoma with the surrounding huge hematoma in the liver. The case presented here is very rare but seems to be suggestive to the natural course and management of hepatocellular adenoma.

Contrast-enhanced agent detection imaging: Early experience in hepatocellular carcinoma

Purpose: To investigate the usefulness of contrast-enhanced Agent Detection Imaging in assessing intratumoral vasculature in hepatocellular carcinoma.Materials and Methods: Fourteen hepatocellular carcinoma nodules in 11 patients were studied with contrast-enhanced Agent Detection Imaging, a wide-band color Doppler imaging method, employing, Levovist®, a microbubble contrast agent. High acoustic power was used with contrast-enhanced Agent Detection Imaging. Intermittent transmission of Agent Detection Imaging was performed at intervals of 200, 500, and 350 milliseconds in the early arterial phase (10 to 40 seconds), late vascular phase (1 to 3 minutes) and postvascular phase (5 to 7 minutes), respectively. The results were compared with those of three-phase dynamic CT.Results: Intratumoral blood vessels in the early arterial phase and tumor parenchymal stain in the late vascular phase were depicted in 12 (88%) of the 14 hepatocellular carcinoma nodules, while all nodules were demonstrated as perfusion defect in the postvascular phase on contrast-enhanced Agent Detection Imaging. The results of Agent Detection Imaging, that were compared with those of dynamic CT, were all 100% : diagnostic sensitivity (12/12), specificity (2/2), and accurary (14/14).Conclusion: Contrast-enhanced Agent Detection Imaging is a promising method for depicting intratumoral vascularity in hepatocellular carcinoma.

Value of new contrast harmonic technique for detecting tumor vascularity in hepatocellular carcinoma: Preliminary results.

Purpose: To investigate the value of a new wide-band contrast harmonic imaging method in depicting intratumoral vascularity in hepatocellular carcinoma.Materials and Methods: Twenty-two patients with 28 hepatocellular carcinoma nodules evaluated with Contrast Harmonic Echo, a new wide-band harmonic imaging method, using Levovist® as a contrast-enhancing agent. Intermittent imaging was carried out in the early arterial phase for 10 to 40 seconds, in the late vascular phase for 1 to 2 minutes, and in the postvascular phase for 5 to 7 minutes. Subtraction images were obtained using the multishot method during the late vascular phase. The ability of Contrast Harmonic Echo imaging to detect vascularity in hepatocellular carcinoma was compared to that of unenhanced color Doppler imaging by analzing results obtained using dynamic CT as a gold standard.Results: Contrast harmonic Echo imaging detected intratumoral vessels, tumor parenchymal stain, and perfusion defect in the early arterial phase, the late vascular phase, and the postvascular phase, respectively. In the late vascular phase, the subtraction image clearly delineated the tumor parenchymal strain. Intratumoral vascularity was detected in 25 (89%) of the hepatocellular carcinoma nodules by Contrast Harmonic Echo, compared with 15 (54%) when color Doppler imaging was used (p<0.05). The diagnostic sensitivity, specificity, and accuracy of Contrast Harmonic Echo were 96.1%, 100% and 96.4%, respectively, corresponding to results obtained using dynamic CT.Conclusion: Contrast Harmonic Echo imaging is superior to unenhanced color Doppler imaging in depicting intratumoral vessels and parenchymal stain, and agrees closely with results obtained with three-phase dynamic CT.

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

ObjectiveTo evaluate the usefulness of contrast-enhanced power Doppler imaging with the personal ultrasound imager in depicting intratumoral vascularity in hepatocellular carcinoma.Materials and MethodsContrast-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.ResultsThe 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.ConclusionThe 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.

Imaging findings of biliary hamartomas (von Meyenburg complexes)

To evaluate the imaging findings of biliary hamartomas (von Meyenburg complexes, vMCs) and discuss their differential diagnosis from other related diseases, imaging findings of biliary hamartomas on ultrasonography (US), computed tomography (CT), magnetic resonance imaging (MRI), magnetic resonance cholangiopancreatography (MRCP), and hepatobiliary scintigraphy were prospectively analyzed in six patients. On ultrasound images, five of the six cases showed multiple small hyper- and hypoechoic lesions with comet-tail echoes, especially when magnified using the zoom function. In all six cases, multiple tiny hypodense lesions less than 10 mm in diameter were scattered throughout the liver with no enhancement on CT. These tiny lesions were demonstrated to be hyper- and hypointense on T2- and TI-weighted images, respectively, in three patients who underwent MRI examinations. MRCP was performed in two patients, and it clearly showed multiple tiny round and irregular-shaped hyperintense lesions. MRCP and hepatobiliary scintigraphy showed normal appearances of intra- and extrahepatic bile ducts in two and one patients, respectively. Imaging modalities are useful in the diagnosis and differential diagnosis of vMCs. A correct diagnosis might be obtained when typical imaging findings present even without histological confirmation.

Spontaneous regurgitation of portal blood flow normalized by meal intake in a patient with alcoholic liver cirrhosis

We report a case with spontaneous regurgitation of portal blood flow (SRPBF) that was normalized by meal intake. A 41-year-old man with long-term alcohol abuse was admitted with a chief complaint of general fatigue. He was diagnosed as having alcoholic liver cirrhosis since his laboratory tests showed the abnormal liver function. Dynamic computed tomography detected numerous portosystemic shunts. Hepatic arterial portography showed the portal vein was narrow and irregular. Color Doppler imaging portrayed the direction of the blood flows in the branches of the portal vein to be retrograde. However, 30 min after meal intake on the same day, color Doppler study showed the direction of the blood flow in the first branch of right and left portal vein became normal. Color Doppler imaging is a useful technique to detect SRPBF and hemodynamic change in portal venous system after meal intake in patient under a completely physiologic condition.