低机械指数谐波超声造影评估肝细胞癌介入治疗效果

目的 探讨低机械指数谐波超声造影在肝细胞癌(HCC)介入治疗中对疗效的评估价值.方法 对82例介入治疗的HCC患者分别于治疗前后进行低机械指数超声谐波造影、常规二维灰阶超声、彩色多普勒血流成像(CDFI)和增强CT和(或)MRI检查,记录病灶数目、大小,观察病灶内血供.结果 82例患者介入治疗前二维超声及CDFI共检出病灶119个,超声造影共检出病灶142个;治疗前后超声造影显示病灶范围均较二维超声所示增大;病灶内血流信号检测以超声造影最准确.结论 超声造影能较好地评估HCC介入治疗的疗效.     

低机械指数谐波超声造影在局灶性肝病治疗适应证选择中的应用

目的:探讨低机械指数谐波超声造影在局灶性肝脏病变治疗适应证选择中的应用价值。方法:对232例(共357个结节)局灶性肝脏病变患者进行低机械指数谐波超声造影、增强CT/MR和/或病理检查。结果:低机械指数谐波超声造影诊断肝脓肿10例,患者行超声导向穿刺抽脓、局部注药治疗;诊断恶性肿瘤147例,其中82例行非手术治疗,包括7例行经皮无水乙醇注射治疗,57例行射频消融或微波凝固治疗,14例行肝动脉化疗栓塞或经皮无水乙醇注射治疗联合射频消融,4例行肝动脉化疗栓塞。结论:超声造影有助于肝脏局灶性病变治疗适应证的选择。     

Evaluation using contrast-enhanced harmonic gray scale sonography after radio frequency ablation of small hepatocellular carcinoma: sonographic-histopathologic correlation.

OBJECTIVE: To evaluate the usefulness of contrast-enhanced harmonic wideband gray scale sonographic images obtained after radio frequency-induced coagulation necrosis, we compared the morphologic and histopathologic characteristics of the ablated tumors with sonographic images of the tumors. METHODS: Forty-eight patients with 72 hepatocellular carcinomas with a maximal diameter of 3 cm or less were treated percutaneously using radio frequency ablation. Six treated tumors in 4 patients were resected 1 month after ablation; the remaining 66 treated tumors were evaluated by a biopsy procedure performed with an 18-gauge fine needle 1 month after ablation. The excised tumors and biopsy specimens were then examined by histopathologic methods, and the findings were compared with those obtained on contrast-enhanced harmonic wideband gray scale sonography. Hematoxylin-eosin-stained specimens were inconclusive as to whether cellular viability remained; therefore, cell viability was determined by a positive result after histochemical (lactate dehydrogenase and nicotinamide adenine dinucleotide phosphate-diaphorase) staining. RESULTS: Contrast-enhanced harmonic wideband gray scale sonography after radio frequency ablation showed residual tumor enhancement in 5 (6.9%) of the 72 tumors; the histopathologic results for these 5 tumors were also positive for tumor residue. The remaining 67 tumors (93.1%) did not show any residual tumor enhancement when examined by sonography; however, only 66 tumors did not reveal tumor residue when examined histopathologically. Contrast-enhanced harmonic wideband sonographic imaging provided results that were comparable with histopathologic findings, the criterion standard for diagnosis; the sensitivity and specificity of the sonographic images for the detection of residual tumor tissue in ablated tumors were 83.3% (5 of 6) and 100% (66 of 66), respectively. CONCLUSIONS: Contrast-enhanced harmonic wideband gray scale sonography is a potentially useful technique for evaluating the therapeutic effects of radio frequency ablation on hepatocellular carcinoma.     

Contrast-enhanced, wide-band harmonic gray scale imaging of hepatocellular carcinoma: correlation with helical computed tomographic findings.

We evaluated the usefulness of contrast-enhanced, wide-band harmonic gray scale imaging for the diagnosis of hepatocellular carcinoma and compared it with helical computed tomography. Forty-eight patients with 61 hepatocellular carcinoma lesions were scanned by contrast-enhanced, wide-band harmonic gray scale imaging after an intravenous bolus injection of the contrast agent Levovist. Fifty-seven of the 61 hepatocellular carcinoma lesions showed hypervascular enhancement, and intratumoral vessels could be observed in 40 of the 57 lesions. Helical computed tomography revealed a high-attenuation area in 54 of the 61 lesions, whereas the other lesions showed an equivocal-attenuation area. Contrast-enhanced, wide-band harmonic gray scale imaging is a useful method for diagnosing the vascularity of hepatocellular carcinoma.     

Contrast-enhanced sonography of autoimmune pancreatitis: comparison with pathologic findings.

OBJECTIVE: We evaluated the vascularity of autoimmune pancreatitis lesions on contrast-enhanced harmonic gray scale sonographic images in comparison with the pathologic findings. METHODS: Six patients with autoimmune pancreatitis were examined. All patients held their breath from 20 to 50 seconds after the injection of a contrast agent while the vascularity of the lesion was examined by contrast-enhanced harmonic gray scale sonography (early phase), and lesion enhancement was monitored at about 90 seconds after the injection while the patients held their breath for a few seconds (delayed phase). We then compared the vascularity on the contrast-enhanced harmonic gray scale sonographic images with the pathologic findings (fibrosis and inflammation) in all lesions. The vascularity of 3 of the 6 lesions was also evaluated by contrast-enhanced harmonic gray scale sonography before and after treatment with corticosteroids. RESULTS: The autoimmune pancreatitis lesions exhibited mild (n = 1), moderate (n = 3), or marked (n = 2) enhancement throughout almost the entire lesions in both the early and delayed phases. The grade of lesion vascularity on the contrast-enhanced harmonic gray scale sonographic images correlated with the pathologic grade of inflammation and inversely correlated with the grade of fibrosis associated with autoimmune pancreatitis. The vascularity of all 3 lesions had decreased on the contrast-enhanced harmonic gray scale sonographic images after steroid therapy. CONCLUSIONS: Contrast-enhanced harmonic gray scale sonography may be useful for evaluating the vascularity of autoimmune pancreatitis lesions and the therapeutic efficacy of steroid therapy.     

Early assessment of the therapeutic response to radio frequency ablation for hepatocellular carcinoma: utility of gray scale harmonic ultrasonography with a microbubble contrast agent.

OBJECTIVE: To evaluate the utility of gray scale harmonic ultrasonography with a microbubble contrast agent in the early assessment of the therapeutic response to radio frequency ablation for hepatocellular carcinoma. METHODS: Seventy-five patients with 81 nodular hepatocellular carcinomas (1.3-4.8 cm) treated with percutaneous radio frequency ablation were evaluated with contrast-enhanced gray scale harmonic ultrasonography after intravenous bolus injection of a galactose-based microbubble contrast agent. The vascularity within the ablation zones was evaluated with a continuous scan for 3 to 5 seconds between 15 and 30 seconds after initiation of contrast agent injection. To evaluate the perfusion of the ablation zones, intermittent stimulated acoustic emission imaging was performed with a rapid sweeping technique from the end of the continuous scan. All patients underwent follow-up 3-phase helical computed tomography at 1 month after radio frequency ablation and were followed for at least 1 year. The results of contrast-enhanced ultrasonography were compared with those of follow-up computed tomography in terms of the presence or absence of residual unablated tumors. RESULTS: In 10 (12%) of the 81 treated hepatocellular carcinomas, contrast-enhanced ultrasonography showed either nodular or crescentic enhancing foci at the margins of ablation zones, suggesting residual unablated tumors. Contrast-enhanced computed tomography obtained 1 month after radio frequency ablation confirmed the residual unablated tumors in the same 10 lesions. Diagnostic agreement between 1-month follow-up computed tomography and contrast-enhanced ultrasonography was achieved in all 81 cases (100%). CONCLUSIONS: Contrast-enhanced gray scale harmonic ultrasonography can be a reliable alternative to contrast-enhanced computed tomography in the early assessment of the therapeutic response to radio frequency ablation for hepatocellular carcinoma.     

The role of contrast-enhanced sonography for radiofrequency ablation of liver tumors.

OBJECTIVE: To assess the feasibility and usefulness of contrast-enhanced sonography for tumor detection and guidance of liver VX2 tumor ablation and to evaluate post radiofrequency ablation effectiveness. METHODS: VX2 tumors were implanted into the livers of 6 rabbits. Both conventional and harmonic gray scale and power Doppler imaging were performed with a commercially available scanner to evaluate the liver tumors before and after intravenous injection of a sonographic contrast agent before and after radiofrequency ablation. Contrast-enhanced imaging was used to detect the tumors before ablation, to guide needle insertion, and to measure the ablation sites after radiofrequency ablation. Pathologic examination was performed for comparison. RESULTS: Three tumors were seen without contrast enhancement, whereas 10 tumors (<1 cm) were detected with contrast enhancement. Intentionally, 2 tumors were completely ablated and 5 tumors were partially ablated. In 3 cases, incompletely ablated tumors could only be identified on contrast-enhanced Doppler imaging by enhancing the detection of residual tumor vascularity. There was excellent concordance between sonographic imaging and gross pathologic findings. CONCLUSIONS: Contrast-enhanced sonographic imaging appears useful for detection of liver tumors and for guiding and monitoring tumor ablation therapies.     

Differential diagnosis of gallbladder diseases with contrast-enhanced harmonic gray scale ultrasonography.

OBJECTIVES: We evaluated the usefulness of contrast-enhanced harmonic gray scale ultrasonographic findings for differential diagnosis of gallbladder diseases. METHODS: We evaluated contrast-enhanced harmonic gray scale ultrasonographic images from 33 patients with 35 polypoid gallbladder disease lesions larger than 10 mm in diameter, consisting of 12 biliary sludge lesions, 8 cholesterol polyps, 1 inflammatory polyp, 2 adenomas, and 12 carcinomas. After a galactosepalmitic acid contrast agent was injected, lesions were scanned by contrast-enhanced harmonic gray scale ultrasonography in 2 phases: early vascular and late vascular. RESULTS: None of the biliary sludge lesions (n = 12) showed either tumor vessels or tumor enhancement. Lesions showing tumor vessels and tumor enhancement on contrast-enhanced harmonic gray scale ultrasonography were diagnosed as cholesterol polyp, inflammatory polyp, adenoma, or carcinoma. Three (38%) of the 8 cholesterol polyps showed dotted-type tumor vessels. Branched-type tumor vessels were observed in 5 (62%) of the 8 cholesterol polyps, the 1 (100%) inflammatory polyp, both (100%) adenomas, and 3 (25%) of the 12 carcinomas. Tortuous-type tumor vessels were observed in 9 (75%) of the 12 carcinomas. Lesions with tumor enhancement and tortuous-type tumor vessels on contrast-enhanced harmonic gray scale ultrasonography were diagnosed as carcinomas, and the sensitivity, specificity, and accuracy of this diagnosis with the current modality were 75% (9/12), 100% (23/23), and 91% (32/35), respectively. CONCLUSIONS: Evaluation of tumor vessels on contrast-enhanced harmonic gray scale ultrasonography may be a useful modality for differentiating gallbladder carcinoma from other polypoid gallbladder disease lesions.     

Contrast-enhanced sonography of small pancreatic mass lesions.

OBJECTIVE: To evaluate the usefulness of contrast-enhanced wideband harmonic gray scale sonography in assessing the vascularity of small pancreatic mass lesions. METHODS: Twenty-five patients with 25 pancreatic mass lesions (20 pancreatic carcinomas, 1 islet cell tumor, 1 malignant lymphoma, and 3 focal inflammatory pancreatic masses due to chronic pancreatitis) were examined. All patients held their breath for 20 to 50 seconds after injection of a contrast agent while the vascularity of the tumor was observed on contrast-enhanced wideband harmonic gray scale sonography (early phase). We then monitored the tumor enhancement 60 to 120 seconds after the injection while the patients held their breath for a few seconds (delayed phase). RESULTS: All 20 (100%) of the pancreatic carcinomas showed no contrast enhancement in the early phase. Fifteen (75%) of the 20 pancreatic carcinomas also showed no contrast enhancement in the delayed phase. The remaining 5 (25%) pancreatic carcinomas showed mild enhancement in the peripheral regions of the tumor in the delayed phase. The other pancreatic masses showed mild or pronounced enhancement throughout the entire lesions in both the early and delayed phases. CONCLUSIONS: Contrast-enhanced wideband harmonic gray scale sonography is a useful tool for differentiating pancreatic carcinomas from focal inflammatory pancreatic masses or hypervascular pancreatic tumors.     

Evaluation of hepatic focal nodular hyperplasia with contrast-enhanced gray scale harmonic sonography: initial experience.

OBJECTIVE: To assess the potential of contrast-enhanced gray scale harmonic sonography in the evaluation of the typical vascular and enhancement patterns of hepatic focal nodular hyperplasia. METHODS: Thirteen patients with 13 lesions of hepatic focal nodular hyperplasia underwent contrast-enhanced gray scale harmonic sonography. After the injection of a microbubble contrast agent (SH U 508A), gray scale harmonic sonographic studies using a Coded Harmonic Angio technique were performed with a combination of a period of continuous scanning to assess the vascular pattern (vascular imaging) and interval delay scanning to determine the sequential enhancement pattern (acoustic emission imaging). Each imaging pattern was categorized and analyzed by consensus of 2 experienced radiologists. RESULTS: In 12 (92%) of 13 lesions, vascular imaging during the arterial phase showed central arteries of a spoked wheel pattern, whereas the remaining lesion had stippled vascularity. On acoustic emission imaging, 11 (85%) of 13 lesions were hyperechoic during the early phase, and the remaining 2 (15%) were isoechoic compared with surrounding parenchyma. Ten (77%) of 13 lesions remained either hyperechoic (5 of 13) or isoechoic (5 of 13) during the delay phase, whereas the remaining 3 lesions (23%) were hypoechoic. CONCLUSIONS: Contrast-enhanced gray scale harmonic sonography showed the typical vascularity of a spoked wheel pattern during the vascular phase and persistent enhancement on serial acoustic emission imaging in most cases of hepatic focal nodular hyperplasia, and thereby it can be a promising technique in noninvasive diagnosis of this entity.     

Hepatocellular carcinoma: therapeutic experience with percutaneous ethanol injection under real-time contrast-enhanced color Doppler sonography with the contrast agent Levovist.

OBJECTIVE: To describe our experience with percutaneous ethanol injection under real-time contrast-enhanced color Doppler sonography with Levovist (SH U 508A; Nihon Schering, Osaka, Japan) for hepatocellular carcinoma after transcatheter arterial infusion. METHODS: Twenty patients (17 men and 3 women; mean age, 58.4 years) with 23 hepatocellular carcinoma nodules (mean +/- SD, 2.7 +/- 1.5 cm) underwent percutaneous ethanol injection under real-time contrast-enhanced color Doppler sonography 1 week after transcatheter arterial infusion. Therapeutic effects were assessed by contrast-enhanced computed tomography and posttreatment fine-needle biopsy. This study was performed on a prospective basis. RESULTS: After the transcatheter arterial infusion, contrast-enhanced color Doppler sonography showed intense intratumoral color signals in all 23 hepatocellular carcinomas. After the percutaneous ethanol injection, contrast-enhanced color Doppler sonography, fine-needle biopsy, and contrast-enhanced computed tomography showed no color signals, no viable tumor tissues, and no enhancement in any of the 23 hepatocellular carcinomas. Three to 5 (mean, 3.3) percutaneous ethanol injection sessions with a 5.2- to 15.6-mL (mean, 12.8-mL) total volume of ethanol per tumor were required for complete disappearance of color signals on contrast-enhanced color Doppler sonography. CONCLUSIONS: Percutaneous ethanol injection under real-time contrast-enhanced color Doppler sonography has considerable efficacy in treating hepatocellular carcinoma.     

Contrast-enhanced power Doppler sonography in breast lesions: effect on differential diagnosis after mammography and gray scale sonography.

OBJECTIVE: To evaluate the efficacy of contrast-enhanced power Doppler sonography in the differential diagnosis of breast lesions after a mammography-gray scale sonography combination. METHODS: Sixty-eight patients with 69 breast masses underwent power Doppler sonography before and after intravenous injection of a contrast agent. The lesions were diagnosed as "highly suggestive of malignancy" (category 5; n = 32), "suspicious" (category 4; n = 21), and "probably benign" (category 3; n = 16) by mammography and gray scale sonography, modeled on the American College of Radiology Breast Imaging Reporting and Data System classification. Power Doppler findings did not affect patient treatment. The authors subjectively evaluated the estimated area of vascularity, degree of enhancement following contrast agent administration, morphologic features, and distribution of vessels within the lesions. RESULTS: The final diagnoses were malignant in 28 lesions and benign in 41. Significant enhancement after contrast agent injection was detected in both the malignant and benign groups. Only 2 criteria, estimated area of vascularity and degree of enhancement following contrast agent administration, proved to be significant diagnostic determinants for contrast-enhanced power Doppler sonography (P < .001; interobserver agreements, 74.4 and 77.8, respectively). Contrast-enhanced power Doppler sonography provided a higher specificity, positive predictive value, and negative predictive value than power Doppler sonography but a lower sensitivity and negative predictive value than mammography-gray scale sonography. Only in the category 4 lesions could the combination of mammography-gray scale sonography and contrast-enhanced power Doppler sonography accomplish a higher specificity (71%) and positive predictive value (70%) than mammography-gray scale sonography (39% and 53%, respectively). CONCLUSIONS: Power Doppler and contrast-enhanced power Doppler sonography cannot be recommended as confirmatory tests in Breast Imaging Reporting and Data System category 3 and category 5 lesions. Although contrast-enhanced power Doppler sonography may help reduce unnecessary biopsies in Breast Imaging Reporting and Data System category 4 lesions, recommendation of its use has many drawbacks, such as imperfectly established criteria, lack of absolute certainty, and high cost.     

超声造影对肝局灶性病变病灶类型诊断的应用价值

目的探讨超声造影对肝局灶性病变病灶类型判断的能力。方法比较研究常规超声及低机械指数超声造影对238例298个肝局灶性病变鉴别诊断的效能。结果298个肝局灶性病变常规超声正确诊断病变类型159个(53.4%),超声造影正确诊断病变类型279个(93.6%),两者比较有统计学差异(P<0.01)。结论超声造影提高了超声正确诊断肝局灶性病变病灶类型的能力。     

Hepatocellular carcinoma: Spectrum of contrast-enhanced gray-scale harmonic sonography findings

Sonography (US) is the most commonly used tool in the assessment of patients with chronic liver disease. Nevertheless, small nodules can be overlooked. Moreover, even if the lesion is readily recognizable, difficulty persists in differentiating hepatocellular carcinoma (HCC) from pre-tumoral, dysplastic stages of nodule evolution. In addition, US is the main tool in guiding percutaneous ablation therapies for HCC and in evaluating patients after treatment, but changes are not specific and difficulties persist in recognizing residual tumor during and after the ablation procedure. Contrast-enhanced, gray-scale, harmonic US offers new possibilities in the imaging of liver tumors. The real-time, low-mechanical index technique employed in our institution allows a true dynamic assessment of the tumor during the various phases of contrast medium circulation. This pictorial essay focuses on typical and atypical appearances of HCC when imaged with contrast-specific, real-time US. Findings useful for lesion detection, differential diagnosis, posttreatment assessment, and follow-up especially are illustrated. The potential role of contrast-enhanced US in various clinical settings is emphasized.     

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.     

超声造影谐频成像对原发性肝癌治疗效果的评价

目的：评价超声造影谐频成像在原发性肝癌治疗后疗效判断方面的作用。方法：使用Levovist对27例33个肝癌结节治疗前后分别行超声造影能量多普勒谐频成像和灰阶谐频成像数字减影检查,结果与动态增强CT相比较。结果：以动态增强CT结果为金标准,治疗前33个肝癌结节,超声造影增强的阳性率为93．9％（31／33）;而对治疗后肝癌,能量多普勒成像显示肿瘤内血流信号的敏感性,特性和准确性均为100％,灰阶谐频成像数字减影则分别为93．9％、100％和96．8％,结论：超声造影谐频成像可以敏感而直观地显示治疗后肿瘤内残存的血流信号,即时评估肿瘤的治疗效果,创伤小,值得临床推广。     

Contrast-enhanced two- and three-dimensional sonography for evaluation of intra-abdominal hemorrhage.

OBJECTIVE: To determine whether a contrast agent enhances sonographic detection of bleeding sites in the abdomen and whether contrast-enhanced three-dimensional sonography provides additional information compared with contrast-enhanced two-dimensional sonography. METHODS: Bleeding sites were created within the livers (n = 3), spleens (n = 5), and kidneys (n = 3) of 3 dogs. A sonographic contrast agent with vascular and parenchymal enhancement capabilities was administered intravenously at a dose of 0.02 mL/kg. Before and after each contrast agent injection, the bleeding sites were imaged with two- and three-dimensional sonography in gray scale harmonic imaging and color flow modes. Sonographic findings were compared with gross pathologic findings. RESULTS: Noncontrast-enhanced sonography was not able to show the specific location of the active bleeding in any of the organs evaluated. The contrast agent enhanced the sonographic detection of blood flow in normal vessels and extravasated blood from damaged vessels or organs in all cases. Intrasplenic and intrahepatic hematomas were better identified on delayed imaging sequences because there was marked enhancement of the normal parenchyma, whereas the hematomas remained unenhanced. Reconstructed three-dimensional sonography showed spatial relationships of the bleeding sites and surrounding structures. Gross pathologic findings were consistent with the contrast-enhanced sonographic results. CONCLUSIONS: Contrast-enhanced sonography improves the detection and evaluation of abdominal bleeding sites. Contrast-enhanced three-dimensional sonography appears to provide additional information when compared with two-dimensional sonography.     

Quantification of tumor vascularity with contrast-enhanced sonography: correlation with magnetic resonance imaging and fluorodeoxyglucose autoradiography in an implanted tumor.

OBJECTIVE: To correlate the quantitated tumor vascularity of implanted murine tumors as depicted by contrast-enhanced sonography with estimates made with magnetic resonance imaging and with estimates of the percentage of viable (metabolically active) tumor as depicted by fluorodeoxyglucose autoradiography. METHODS: Implanted tumors in 10 mice were imaged with contrast-enhanced sonography, magnetic resonance imaging, and fluorodeoxyglucose autoradiography. Tumor vascularity was estimated with each modality and compared with the percentage of viable tumor. RESULTS: Quantitated estimates of tumor vascularity with contrast-enhanced sonography closely correlated (r = 0.95) with estimates made by magnetic resonance imaging and with the percentage of viable tumor (r = 0.93) as depicted by fluorodeoxyglucose autoradiography. CONCLUSIONS: Contrast-enhanced sonography accurately depicts tumor vascularity in these implanted tumors. Tumor vascularity correlated with the amount of metabolically active tumor.     

Diagnosis of advanced hepatocellular carcinoma using contrast-enhanced harmonic gray-scale imaging with enhancement agents (Levovist): Correlation with helical CT and US angiography

We compared contrast-enhanced harmonic gray-scale imaging with helical CT and US angiography to evaluate vascularity in advanced hepatocellular carcinoma (HCC). Contrast-enhanced harmonic gray-scale imaging using Levovist (Nihon Schering, Tanabe) as the contrast agent and enhanced helical CT were performed on 38 patients with 45 lesions (29 men and 9 women aged 41 to 83 years; mean age, 66 years; mean maximum tumor diameter, 30.5±23.0 mm), and angiography was performed to evaluate 37 lesions from 32 of these 38 patients (24 men and 8 women, aged 41 to 79 years; mean age, 65 years; mean maximum tumor diameter, 27.9±17.9 mm). Contrast-enhanced harmonic gray-scale imaging showed hypervascular enhancement in 41 of the 45 lesions; the other 4 lesions were not visualized as hypervascular because 3 of the them could not be detected with non-enhanced US and the remaining lesion was situated deep in the liver and more than 11 cm from the surface of the body. Helical CT showed areas of high attenuation in 40 of the 45 lesions, leaving the other 5 lesions equivocal, while US angiography achieved positive enhancement in 36 of 37 lesions. Intratumoral vessels were visualized with contrast-enhanced harmonic gray-scale imaging in 25 of the 45 lesions; however; intratumoral vessels were seen in only 4 of the 45 lesions examined with helical CT. In evaluating vascularity in advanced HCC, contrast-enhanced harmonic gray-scale imaging with Levovist was as effective as US angiography and more effective than helical CT. Motion artifacts produced by the heart make it difficult to evaluate vascularity in advanced HCC located in the left lobe of the liver with Doppler sonography. Contrast-enhanced harmonic gray-scale imaging can show intratumoral vessels and hypervascular enhancement of the tumor without motion artifacts, however, even when the tumor is located near the heart or large vessels. Contrast-enhanced harmonic gray-scale imaging is useful for evaluating vascularity in advanced HCC when the tumor can be visualized with non-enhanced US.     

Tissue harmonic imaging: utility in breast sonography.

OBJECTIVE: To determine the impact of tissue harmonic imaging on visualization of focal breast lesions and to compare gray scale contrast between focal breast lesions and fatty tissue of the breast between tissue harmonic imaging and fundamental frequency sonography. METHODS: A prospective study was performed on 219 female patients (254 lesions) undergoing sonographically guided fine-needle biopsy. The fundamental frequency and tissue harmonic images of all lesions were obtained on a scanner with a wideband 7.5-MHz linear probe. Twenty-three breast carcinomas, 6 suspect lesions, 9 fibroadenomas, 1 papilloma, 1 phyllodes tumor, 162 unspecified solid benign lesions, and 40 cysts were found. In 12 cases the fine-needle aspiration did not yield sufficient material. The gray scale intensity of the lesions and adjacent fatty tissue was measured with graphics software, and the gray scale contrast between lesions and adjacent fatty tissue was calculated. RESULTS: Tissue harmonic imaging improved the gray scale contrast between the fatty tissue and breast lesions in 230 lesions (90.6%; P < .001) compared with fundamental frequency images. The contrast improvement was bigger in breasts with predominantly fatty or mixed (fatty/glandular) composition than in predominantly glandular breasts. The overall conspicuity, lesion border definition, lesion content definition, and acoustic shadow conspicuity were improved or equal in the harmonic mode for all lesions.CONCLUSIONS: The tissue harmonic imaging technique used as an adjunct to conventional breast sonography may improve lesion detectability and characterization.