The role of late-phase pulse inversion harmonic imaging in the detection of occult hepatic metastases.

OBJECTIVE: The purpose of this study was to investigate the efficacy of late-phase pulse inversion harmonic imaging (PIHI) in detecting occult metastases and to compare the results with helical computed tomography (CT) in a group of patients whose fundamental liver sonographic results were normal. METHODS: Thirty-two patients (21 women and 11 men; age range, 20-87 years) with a known primary malignancy were enrolled in the study. The patients were evaluated with conventional sonography, unenhanced PIHI, and PIHI 3 minutes after the injection of Levovist (SH U 508A; Schering AG, Berlin, Germany). All patients also underwent triphasic helical CT within 1 week after sonography. In 1 patient, mangafodipir-enhanced magnetic resonance imaging was performed as part of the clinical workup. RESULTS: After Levovist injection, in 4 (12.5%) of 32 patients, at least 1 hypoechoic lesion was detected by PIHI; multiple lesions were shown in 1 patient. The mean diameter of newly detected lesions was 12 mm. Triphasic helical CT also showed all of the lesions that were detected by PIHI. The diagnoses were confirmed by biopsy and CT findings in 2 patients and by the typical CT and magnetic resonance imaging findings in 1 patient. For the fourth patient, the diagnosis was confirmed by follow-up and CT. Conclusions. Late-phase PIHI is comparable to helical CT for detecting occult hepatic metastases, but it protects patients from the potentially hazardous effects of radiation and iodinated contrast agents. Further series involving a larger number of patients are needed to determine its place in the evaluation of cancer staging and treatment planning.     

Contrast-enhanced agent detection imaging: value in the characterization of focal hepatic lesions.

OBJECTIVE: To assess the value of SH U 508A-enhanced agent detection imaging in the characterization of focal hepatic lesions. METHODS: Contrast-enhanced agent detection imaging was performed on 78 focal hepatic lesions: 34 hepatocellular carcinomas, 22 metastases, 9 hemangiomas, 9 abscesses, 3 cysts, and 1 focal nodular hyperplasia. After administration of SH U 508A, interval delay scanning with agent detection imaging was performed with intervals of approximately 7 seconds (phase I), 30 seconds (phase II), and 90 seconds (phase III) after the first arrival of the contrast agent to the liver. Two observers blinded to the final diagnosis reviewed selected images and assessed the enhancement patterns of the lesions. For quantitative analysis, we calculated the enhancement ratio of the lesions and the difference of enhancement between the lesions and the liver parenchyma. RESULTS: Agent detection imaging showed a distinctive enhancement pattern in focal liver lesions compared with that in the liver. Hepatocellular carcinomas were characterized by early enhancement (phase I) and washout (phases II and III; sensitivity, 94.1%; specificity, 93.2%; positive predictive value, 91.4%). Metastases showed peripheral rim or targetlike enhancement (phase I, phase II, or both) and a defect (phase III) and had sensitivity of 77.3%, specificity of 100%, and a positive predictive value of 100%. Hemangiomas showed peripheral nodular or inhomogeneous (phase I, phase II, or both) and gradually centripetal (phase II, phase III, or both) enhancement (sensitivity, 88.9%; specificity, 100%; positive predictive value, 100%). Abscesses were partially enhanced from phase I to phase III (sensitivity, 66.7%; specificity, 95%; positive predictive value, 85.7%). The results of the quantitative analysis of lesion enhancement were compatible with those of the qualitative analysis. CONCLUSIONS: SH U 508A-enhanced agent detection imaging may yield distinctive enhancement characteristics in focal liver lesions that would contribute positively to the characterization of these hepatic lesions.     

Detection and differential diagnosis of hepatic masses using pulse inversion harmonic imaging during the liver-specific late phase of contrast enhancement with Levovist

PURPOSE: The purpose of this study was to investigate whether late-phase pulse inversion harmonic imaging (PIHI) increases conspicuity in hepatic masses, helps to differentiate benign from malignant lesions, and demonstrates a greater number of and smaller metastatic lesions than do conventional (fundamental) sonography and helical CT. METHODS: Thirty patients (17 women and 13 men; age range, 35-77 years; mean age, 54 years) with known or suspected liver masses were evaluated using both fundamental sonography and contrast-enhanced PIHI during the liver-specific late phase of Levovist. The patients also underwent contrast-enhanced triphasic helical CT examinations within 1 week after sonography. In 4 of the patients, gadolinium-enhanced MRI was also performed as a part of their clinical work-up. RESULTS: The increase in the lesions' conspicuity on PIHI compared with fundamental sonography was significantly greater in malignant lesions than in benign lesions (p< 0.001). An echogenic rim was observed on PIHI in 8 (53%) of 15 malignant lesions. The mean number of metastatic lesions visualized on PIHI (5.5 +/- 5.3) was significantly higher than the mean number visualized on fundamental sonography (2.5 +/- 2.1, p < 0.05). Although lesions as small as 3 mm were observed on PIHI, the mean sizes of the smallest lesions demonstrated using fundamental sonography, PIHI, and helical CT were not significantly different. CONCLUSIONS: Late-phase PIHI is a useful technique for characterizing hepatic lesions and demonstrating both a greater number of and smaller metastases. It may help to differentiate benign from malignant liver masses and may obviate unnecessary and expensive further imaging.     

菲立磁增强MRI在肝脏局灶性病变诊断中的应用

评价菲立磁的安全性及在肝脏局灶性病变的检出及鉴别诊断中的作用。方法 30例B超或CT发现肝内局限性病灶的患者进行菲立磁增强（0.05ml/kg,静脉滴入）前后MRI扫描。结果 所有患者增强后天生命体征改变,也未出现严重不良反应。恶性病例16例,增强前发现病灶28个,增强后48个,多发现20个,均为转移处。89.6%的病灶增强后信号无降低,10.4%略降低。良性14例,多数良性病变（10／12,囊肿除外）信号可见不同程度减低。结论 菲立磁是一种安全、有效的肝脏阴性造影剂,对肝脏局灶性病变的良恶性鉴别有一定作用,能明显提高肝脏转移瘤的检出率。     

Ultrasonographic evaluation of focal hepatic lesions: comparison of pulse inversion harmonic,tissue harmonic,and conventional imaging techniques.

A prospective study was performed to evaluate whether pulse inversion harmonic imaging and tissue harmonic imaging improve the lesion conspicuity and change ultrasonographic characteristics of focal hepatic lesions. Three radiologists evaluated 97 focal hepatic lesions by consensus: cirrhosis‐related nodules (n = 23), metastases (n = 23), hemangiomas (n = 27), and cysts (n = 24). In our study, pulse inversion harmonic imaging was judged superior to both tissue harmonic imaging and conventional imaging in conspicuity and overall quality for cirrhosis‐related nodules, metastases, and cysts (P < 0.05). Compared with conventional imaging, both pulse inversion harmonic imaging and tissue harmonic imaging provided better conspicuity, clearer internal echogenicity, and stronger through‐transmission of cysts (P < 0.05). Pulse inversion harmonic imaging was judged to be better in depicting internal morphology for cirrhosis‐related nodules and metastases than conventional imaging (P < 0.05). For hemangiomas, no statistically significant difference was found in all parameters except better posterior enhancement by tissue harmonic imaging than other techniques. In conclusion, pulse inversion harmonic imaging showed the best conspicuity and also enhanced characteristics of both cystic and solid hepatic lesions. Tissue harmonic imaging was judged superior to conventional imaging in evaluating cysts but was not beneficial for solid lesions. The results of this trial may be specific to the machine used for this study.     

Characterization of hyperechoic focal liver lesions: quantitative evaluation with pulse inversion harmonic imaging in the late phase of levovist.

OBJECTIVE: The aim of this study was to evaluate hyperechoic focal liver lesions with pulse inversion harmonic imaging in the late phase of SH U 508A (Levovist; Schering AG, Berlin, Germany) and to determine whether quantitative evaluation improves the characterization of the lesions. METHODS: Twenty-six patients with hyperechoic liver lesions were enrolled in this study. Pulse inversion harmonic imaging was performed before and after administration of Levovist. Scan data were digitally stored, and each lesion was analyzed with a personal computer-based quantification package. All lesions were confirmed by histologic or triphasic spiral computed tomographic examinations. The intensity was measured in decibels in regions of interest drawn within the lesion and surrounding liver parenchyma. The lesion-liver ratios were than calculated. After contrast agent administration, a ratio equal to or greater than 1 was presumed benign, whereas a ratio of less than 1 was considered malignant. RESULTS: Nine malignant (7 metastases, 1 hepatocellular carcinoma, and 1 cholangiocarcinoma) and 17 benign (14 hemangioma, 1 focal nodular hyperplasia, 1 focal fatty change, and 1 inflammatory pseudotumor) hyperechoic lesions were quantitatively evaluated. All malignant (n = 9) and 2 benign lesions (1 hemangioma and 1 inflammatory pseudotumor) had ratios of less than 1. In 15 of 17 benign lesions, the ratios were equal to or greater than 1. The intensity ratios calculated for benign and malignant lesions showed a statistically significant difference (P < .05). CONCLUSIONS: Pulse inversion harmonic imaging with quantitative evaluation facilitates the differential diagnosis of hyperechoic focal liver lesions. A lesion-liver ratio equal to or greater than 1 predicts a benign nature, assuming that malignant lesions show a ratio of less than 1.     

肝局灶性病变超声造影反向脉冲谐波显像的临床研究

目的 探讨不同肝局灶性病变在超声造影反向脉冲谐波显像时的动态灌注过程及其特征。方法 对7例肝细胞性肝癌，6例转移性肝肿瘤，1例腺瘤，6例血管瘤，1例局灶性脂肪浸润，3例局灶性慢性炎症，1例多房囊肿共25个肝局灶性病变进行超声造影反向脉冲谐波动态显像，观察病灶内及肝实质的灌注过程。结果 25例均观察到动脉期(5～24s)、门脉期(19～85s)、实质期(200～320s)。7例肝细胞性肝癌均为肝动脉期完全显著增强；5例转移癌为门脉期增强，2例在实质期发现更多病灶；6例血管瘤均显示出特征性的填充式增强；2例慢性炎症及1例脂肪浸润未见增强；1例腺瘤为门脉期显著增强；1例多房囊肿则为实质期低回声缺损。结论 超声造影反向脉冲谐波显像可清晰显示肝局灶性病变及肝实质的动态灌注过程，对诊断和鉴别诊断具有明确的临床应用价值。     

MR imaging in the evaluation of hepatic metastases

Optimal detection of focal hepatic lesions in patients with metastases can alter patient management and result in significant cost savings by reducing the number of unnecessary laparotomies for unresectable disease. Liver-specific MR imaging contrast agents (reticuloendothelial and hepatobiliary agents) offer greater lesion-to-liver contrast than the conventional extracellular fluid space MR imaging contrast agents (gadolinium chelates), which have a nonspecific distribution. For the detection of hepatic metastases, although the work of Seneterre et al suggests that the accuracy of ferumoxide-enhanced MR imaging is equivalent to that of CTAP, other studies find CTAP to be superior. Comparisons of reticuloendothelial agents and hepatobiliary agents for imaging liver metastases are lacking in the literature. Further studies comparing MR imaging enhanced with liver-specific contrast agents to CTAP are needed to determine if hepatic MR imaging can replace CTAP for the preoperative evaluation of hepatic metastases. For the characterization of focal liver lesions, MnDPDP and ferumoxides have been added to the small list of FDA-approved contrast agents, and both can help to increase diagnostic specificity. Two of the hepatobiliary agents which are not yet approved, Gd-BOPTA and Gd-EOB-DTPA, have the potential of characterizing liver lesions during dynamic contrast enhancement (similar to Gd-DTPA) and during the hepatocyte phase (similar to MnDPDP), and may increase the detection of focal liver lesions.     

Pulse inversion sonography in the early phase of the sonographic contrast agent Levovist: differentiation between benign and malignant focal liver lesions.

OBJECTIVE: To determine whether examination of focal liver lesions by pulse inversion sonography in the early perfusion phase of the contrast agent Levovist (SH U 508A; Schering AG, Berlin, Germany) enables distinction between benign and malignant lesions. METHODS: Seventy-two patients were examined. The cause of the lesion was confirmed by liver biopsy, computed tomography, or both or by hepatic iminodiacetic acid-enhanced scintigraphy. Forty-two patients had malignant liver lesions, and 30 had benign liver lesions. After injection of 2 g of Levovist intravenously, analysis of Levovist arrival was performed by the interval delay imaging technique for 60 seconds. RESULTS: The early arrival of Levovist less than 30 seconds after injection was used as an indicator for malignancy and had specificity of 67% and sensitivity of 60% (P < .05). The central starlike fill-in as a sign for focal nodular hyperplasia had specificity of 100% and sensitivity of 67% (P < .001). The rimlike pattern followed by centripetal fill-in as a sign for hemangioma had specificity of 100% and sensitivity of 18% (P < .01). In contrast, the early diffuse stippled arrival pattern was found in 60% of malignant lesions and also in 33% of cases of focal nodular hyperplasia and in 1 patient with an adenoma. CONCLUSIONS: Analysis of Levovist arrival time cannot distinguish between a malignant or benign lesion in individual cases. However, the central starlike arrival pattern is characteristic of focal nodular hyperplasia.     

Hepatic MR imaging: comparison of 2D and 3D gradient echo techniques

BACKGROUND: To compare fat-suppressed three-dimensional gradient echo (3D-GRE) and two-dimensional gradient echo (2D-GRE) techniques for hepatic magnetic resonance imaging. METHODS: For 107 patients with suspected focal hepatic lesions, unenhanced 2D-GRE multislice in-phase and opposed-phase images and 3D-GRE images were obtained. Two radiologists independently and in random order reviewed the images. Quantitative analysis compared contrast-to-noise ratio (C/N) of liver masses and of the liver to spleen and signal-to-noise ratio (S/N) of the liver. Subjective grading of lesion conspicuity, confidence for lesion detection, artifacts, and overall image quality were also evaluated. RESULTS: Conspicuity and confidence for focal lesions was statistically significantly higher on 3D-GRE than on 2D-GRE images. Liver-to-spleen C/N was higher on 3D-GRE images than on in-phase and opposed-phase 2D-GRE images (p < 0.01). Liver S/N was higher on in-phase 2D-GRE images than on 3D-GRE and opposed-phase 2D-GRE images (p < 0.001). Lesion-to-liver C/N was higher on 3D-GRE images than on 2D-GRE images for nonsolid lesions (p < 0.05), but there was no significant difference for solid lesions. Motion and pulsation artifacts were significantly fewer on 3D-GRE images, but graininess and shading were significantly higher. Overall image quality was not significantly different for the three sequences. CONCLUSION: Fat-suppressed 3D-GRE sequences can afford comparable or better image quality than 2D-GRE images and may have the potential to detect more focal hepatic lesions.     

彩色多普勒血流显像评价肾癌的血管性——一种新的超声造影剂的应用价值

目的：评价超声造影剂利声显对彩超检测肾细胞癌血流状况的增强效应,并探讨其临床应用价值。资料与方法：应用彩色多普勒血流显像检查１９例（个）肾细胞癌,均经手术病理证实,经周围静脉注射超声造影剂利声显（ＳＨＵ５０８Ａ）,浓度３００ｍｇ／ｍｌ,平均注射剂量７９ｍｌ。观察注射前后瘤内血流信号显像情况。结果：超声造影前１９个肾癌彩超显示４个无血流信号,１１个周边部分环绕血流,４个瘤周瘤内见散在点状、短条状血流;超声造影后,１９个肾癌瘤内血流信号均增强,１６／１９（８４．２１％）明显增强,３／１９（１５．７９％）轻度增强,增强效应主要表现为血流信号明显增多,分布区域增大,血管显示段延长,分枝更清晰完整。结论：超声造影剂利声显能显著增强肾细胞癌内彩色多普勒血流信号,更完整显示肾癌的血管形态、分布等,明显改善彩超对肾癌血供的评价,对肾肿瘤诊断有重要的临床应用价值。     

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.     

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.     

Acoustic Radiation Force Impulse Elastography for the Evaluation of Focal Solid Hepatic Lesions: Preliminary Findings

This study was designed to investigate the potential usefulness of acoustic radiation force impulse (ARFI) elastography to evaluate focal solid hepatic lesions. In total, 51 patients with 60 focal hepatic lesions, which included 17 hemangiomas, 25 hepatocellular carcinomas (HCCs), 15 metastases and three cholangiocarcinomas, underwent ARFI elastography. The lesions were classified into three groups: Group I consisted of metastatic liver tumors and cholangiocarcinomas, group II consisted of HCCs and group III consisted of hemangiomas. The stiffness and conspicuity of the tumors as depicted on ARFI elastography and the echogenicity and conspicuity of the tumors on corresponding B-mode images were analyzed. Shear wave velocity was obtained to quantify stiffness for 36 focal hepatic lesions: 11 hemangiomas, 17 HCCs and eight other malignant lesions.     

肝脏局灶性结节增生的平扫及动态增强MRI表现

目的分析肝脏局灶性结节增生(FNH)MRI平扫及动态增强表现,提高对该病的认识和诊断水平。方法回顾性分析19例共20个经手术病理证实的FNH病灶,所有病例均行MRI平扫及动态增强检查,对病灶的MRI特征进行评价。结果18例为单发病灶,1例为2个病灶,病灶位于左外叶6个、左内叶9个、右后叶4个、尾状叶1个;病灶大小平均为3.6cm×4.5cm;与肝实质比较,平扫T1WI序列为稍低信号、T2WI序列为稍高信号者16个,T1WI及T2WI为等信号者4个,9个病灶内见瘢痕,呈长T1长T2信号。动态增强扫描动脉期18个病灶明显强化,1个病灶中等程度强化,1个病灶周边轻度强化,2个病灶周边出现扭曲血管;门脉期信号高于周围肝实质者17个,等信号2个,信号相对低于肝实质1个;延迟期仍为高信号者14个,另5个表现为等信号,1个为稍低信号;门脉期和延迟期有3个病灶周围可见细环状包膜;15个病灶增强后其内可见瘢痕影,瘢痕于动脉期、门脉期均为低信号,延迟强化者4例。所有病灶周围静脉显示良好。结论MRI平扫及动态增强扫描能较好地显示FNH的内部结构和信号特点,反映病灶的血供特点和病理特征,有助于和肝脏其他病变相鉴别。     

MR imaging features of focal liver lesions in Wilson disease

Hepatic involvement in Wilson disease (WD) manifests as a diffuse chronic disease in the majority of patients. However, in a subset of patients focal liver lesions may develop, presenting with a wide range of imaging features. The majority of focal liver lesions in patients with WD are benign nodules, but there are reports that have described malignant liver tumors or dysplastic nodules in these patients. Because of the possibility of malignant transformation of liver nodules, major concerns have been raised with respect to the management and follow-up of patients with WD in whom focal liver lesions have been identified. The assessment of liver involvement in patients with WD is generally performed with ultrasonography. However, ultrasonography conveys limited specificity so that magnetic resonance (MR) imaging is often performed to improve lesion characterization. This review was performed to illustrate the spectrum of MR imaging features of focal liver lesions that develop in patients with WD. It is assumed that familiarity with the MR imaging presentation of focal liver lesions in WD may help clarify the actual nature of hepatic nodules in patients with this condition.     

Improvement of endocardial border delineation in suboptimal stressechocardiograms using the new left heart contrast agent SH U 508 A

Recent studies have shown that the saccharide based echocardiographic contrast agent SH U 508 A opacifies the left ventricle after i.v. injection, thus possibly improving endocardial border definition. This study was performed to determine whether SH U 508 A can enhance the wall motion analysis in suboptimal echocardiographic images at rest and following pharmacological stress. Ten male patients (mean 58 years) exhibiting ≥30% endocardial border dropout were examined prior to a diagnostic left heart catheterization. Five patients were stressed with Dobutamine, 5 with Dipyridamole. The wall motion was assessed visually (qualitatively) as well as computer-aided (quantitatively). The concordance between left ventricular angiography as ‘gold standard’ and resting echocardiography regarding the wall motion analysis was significantly improved from 64.5% to 90.3% following the injection of SH U 508 A (p < 0.05). A delineation score (0 = not delineated, 1 = delineated) of 12 individual wall segments was used. The mean delineation score at baseline was 6.1 ±1.4 at rest and 6.6 ±1.9 during stress. SH U 508 A significantly (p < 0.01) increased the score to 9.6 ±1.9 and 10.3 ±1.7, respectively. The intraobserver variability for assessing the delineation score was significantly (p < 0.04) improved by SH U 508 A. SH U 508 A, however, did not improve the quantitative assessment of the left ventricular function. Only 40% of the patients could be analyzed following SH U 508 A injection. No severe adverse reactions were seen. SH U 508 A led to a significant, clinically important, improvement in the interpretation of stress echocardiograms in patients with inconclusive routine echocardiograms.     

Hepatic metastases: use of diffusion-weighted echo-planar imaging

Diffusion-weighted MR imaging is increasingly applied to detect and characterize focal hepatic lesions. In this update article, technical aspects regarding diffusion-weighted echo-planar imaging (DW-EPI) of the liver will be addressed, and concepts for image interpretation will be provided. The value of DW-EPI for the detection of hepatic metastases is illustrated on the basis of a review of the literature and our personal experience. In this respect, special emphasis is given to the comparison of DW-EPI with well-established MR imaging techniques such as T2-weighted and contrast-enhanced MR imaging, and advantages and limitations of DW-EPI will be described. Based on the review, it is concluded that DW-EPI is more sensitive than T2-weighted MR imaging and at least as accurate as superparamagnetic iron oxide-enhanced or gadolinium-enhanced MR imaging for the detection of hepatic metastases. Although difficulties occasionally arise in further characterizing small lesions detected with DW-EPI, substantial improvements in the preoperative evaluation of liver metastases in candidates for hepatic resection may be expected.     

Phase inversion harmonic imaging improves assessment of renal calculi: a comparison with fundamental gray-scale sonography

PURPOSE: To compare phase inversion harmonic imaging (PIHI) with fundamental imaging (FI) in the evaluation of renal calculi. METHODS: Thirty adult patients with renal calculi (17 men, 13 women; mean age 44 years [range, 25-71]) underwent transabdominal sonographic examination of the urinary system. Both kidneys and renal calculi were examined with PIHI and FI. Overall renal conspicuity, calculus visibility, and clarity of posterior shadowing were assessed subjectively using a 4-point scale (0 being the worst, 3 being the best). The maximum diameter of the calculi was measured using both techniques. The effect of body mass index on qualitative scoring and quantitative measurements was evaluated. RESULTS: PIHI improved overall renal conspicuity compared with FI (p < 0.001). The visibility of the calculi and clarity of posterior shadowing were significantly better with PIHI than with FI (p < 0.001 for both parameters). The maximum diameter of calculi was larger with PIHI than with FI (p < 0.001). The superiority of PIHI over FI regarding overall conspicuity of the kidney, visibility of the calculus, and clarity of posterior shadowing scores increased in the obese group (p < 0.001 for all 3 parameters). The mean calculus diameter difference between the 2 techniques was significantly higher in the obese group. CONCLUSION: The routine use of PIHI is recommended in the evaluation of renal calculi.     

Therapeutic response evaluation of malignant hepatic masses treated by interventional procedures with contrast-enhanced agent detection imaging.

OBJECTIVE: To assess the usefulness of microbubble contrast-enhanced agent detection imaging in evaluating the therapeutic response of malignant hepatic masses to treatment with interventional procedures. METHODS: Fifty-eight patients with 68 hepatocellular carcinomas and 6 metastases who were treated with interventional procedures were evaluated with SH U 508A-enhanced agent detection imaging and helical computed tomography. Helical computed tomography was also performed to help establish the outcome of therapy with unenhanced computed tomography 2 weeks after transcatheter arterial chemoembolization and with dynamic contrast-enhanced computed tomography 1 day after radio frequency ablation or percutaneous ethanol injection. The studies were reviewed separately and randomly, and the sensitivity and specificity of agent detection imaging for detection of viable tumor residue were determined by follow-up imaging performed at least 3 months later. RESULTS: Follow-up computed tomography or magnetic resonance imaging revealed complete tumor responses in 44 (59.5%) of 74 cases after the therapeutic procedures. The sensitivity of agent detection imaging was 94.7% after transcatheter arterial chemoembolization and 72.7% after radio frequency ablation and percutaneous ethanol injection. The specificity of agent detection imaging for the detection of residual tumors was 80% after transcatheter arterial chemoembolization and 79.2% after radio frequency ablation and percutaneous ethanol injection. The false-positive rate for agent detection imaging in cases of radio frequency ablation or percutaneous ethanol injection was 20.8% (5 of 24), resulting from reactive hyperemia or vascularity within the safety margin. In the assessment of the therapeutic effects, the concordance of contrast-enhanced agent detection imaging with helical computed tomography was statistically significant after transcatheter arterial chemoembolization (P < .00001) and radio frequency ablation or percutaneous ethanol injection (P < .02). CONCLUSIONS: Contrast-enhanced agent detection imaging proved useful and as effective as helical computed tomography for evaluating the therapeutic effects of interventional therapeutic procedures for malignant hepatic masses.