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1.
Quantitative dynamic contrast-enhanced sonography of hepatic tumors   总被引:8,自引:0,他引:8  
Liver tumors are defined using quantitative dynamic contrast-enhanced ultrasound compared to histological diagnosis, respectively, long-term follow-ups. Forty-two focal liver lesions in 39 patients were examined by contrast harmonic imaging over a period of 2 min after bolus injection of 10-ml galactose-based contrast agent. Vascular enhancement was quantified by using a dedicated software that allowed us to place representative regions of interest (ROI) in the center of the lesion, in the complete lesion, in regular liver parenchyma and in representative liver vessels (artery, vein and portal vein). Peak enhancement was judged to be either in the arterial, portal venous or in the late phase of liver perfusion. The lesion was described as hypovascular, isovascular and hypervascular compared to liver parenchyma. Contrast uptake was described as centrifugal or centripetal and peripheral or homogenous, respectively. Characterization of the lesions was performed unenhanced and after contrast by four independent specialists unaware of histology. Diagnosis of malignancy was evaluated by using a receiver operating characteristic (ROC) analysis, also overall accuracy, average sensitivity, specificity and negative and positive predictive values were calculated. Interobserver agreement was defined by the Kappa statistics. Histologic examination revealed 29 malignant [hepatocellular carcinoma (HCC), n=11; cholangiocellular carcinoma (CCC), n=1; lymphoma, n=1; metastases, n=16)] and 7 benign [hemangioma, n=1; focal nodular hyperplasia (FNH), n=4, adenoma, n=2)] lesions. Six benign lesions (hemangioma n=1; FNH n=5) were proved by long-term follow-up. ROC analysis regarding the diagnosis of malignancy showed values from 0.43 to 0.62 (mean 0.57) before and from 0.70 to 0.80 (mean 0.75) after contrast agent, respectively. The average values for sensitivity, specificity, accuracy and negative and positive predictive values were 66, 26, 62, 45 and 73% unenhanced and 83, 49, 73, 65 and 82% after contrast, respectively. The interobserver agreement was 0.54 and 0.65 for unenhanced and enhanced examinations, respectively. Quantitative dynamic contrast-enhanced sonography improves the diagnosis of malignancy in liver lesions.  相似文献   

2.

Aims

We assessed the role of contrast-enhanced ultrasound (CEUS) in the differential diagnosis between benign and malignant portal vein thrombosis (PVT) in patients who had liver tumors.

Methods

Seventeen consecutive patients who had cirrhosis, liver tumors, and PVT were prospectively studied with CEUS. CEUS was performed at low mechanical index after intravenous administration of a second-generation contrast agent (SonoVue, Bracco, Milan, Italy). Presence or absence of thrombus enhancement on CEUS were considered diagnostic for malignant or benign PVT. Five patients also underwent percutaneous portal vein fine-needle biopsy under US guidance. All patients were followed-up. Shrinkage of the thrombus and/or recanalization of the vessels on CDUS during follow-up were considered definitive evidence of the benign nature of the thrombosis, whereas the enlargement of the thrombus, disruption of the vessel wall, and parenchymal infiltration over follow-up were considered consistent with malignancy.

Results

Follow-up showed signs of malignant thrombosis in 14 of 17 patients. CEUS showed early arterial enhancement of the PVT in 14 patients of 14 malignant PVT, 1 patient of 3 benign PVT and the absence of thrombus enhancement in 2 patients of 3 benign PVT. FNB confirmed the results for malignant PVT in four of five patients, for benign granulomatous inflammation PVT in one of five patients in which CEUS showed early arterial enhancement of the PVT. The sensitivity, specificity and accuracy is 100%, 66.7% and 93.3% at diagnosis of malignant PVT using CEUS. In one patient with intrahepatic bile duct stone, CEUS were positive for malignant PVT, whereas FNB was negative (benign granulomatous inflammation PVT); follow-up examination confirmed benign PVT.

Conclusion

CEUS seems to be the pretty sensitive and specific test for diagnosing malignant portal vein thrombosis in patients with cirrhosis and tumors.  相似文献   

3.
目的:探讨腮腺肿瘤的CT诊断价值。方法:回顾性分析经手术及病理证实的腮腺肿瘤20例,其中良性肿瘤12例,恶性肿瘤8例。结果:12例良性肿瘤中,形态规则、边界清晰者11例,边界不清者1例;其中8例行增强扫描,均表现为轻至中度强化,其中密度均匀者5例,密度不均者3例。8例恶性肿瘤中,形态不规则、边界不清并伴邻近组织器官受侵者7例,边界清楚、形态规则者1例;其中6例行增强扫描,均见不同程度强化,肿瘤密度均匀者1例,密度不均者5例,其中2例中心可见大片低密度坏死;8例恶性肿瘤中,4例合并颈部淋巴结肿大,3例面神经受累。结论:CT扫描对腮腺肿瘤的诊断及鉴别诊断具有重要价值。  相似文献   

4.
RATIONALE AND OBJECTIVES: The purpose of this study was to compare gadolinium-enhanced magnetic resonance (MR) angiography with contrast material-enhanced computed tomography (CT) for the detection of small (4-5-mm) pulmonary emboli (PE), with a methacrylate cast of the porcine pulmonary vasculature used as the diagnostic standard. MATERIALS AND METHODS: In 15 anesthetized juvenile pigs, colored methacrylate beads (5.2 and 3.8 mm diameter-the size of segmental and subsegmental emboli in humans) were injected via the left external jugular vein. After embolization, MR angiographic and CT images were obtained. The pigs were killed, and the pulmonary arterial tree was cast in clear methacrylate, allowing direct visualization of emboli. Three readers reviewed CT and MR angiographic images independently and in random order. RESULTS: Forty-nine separate embolic sites were included in the statistical analysis. The mean sensitivity (and 95% confidence intervals) for CT and MR angiography, respectively, were 76% (68%-82%) and 82% (75%-88%) (P > .05); the mean positive predictive values, 92% (85%-96%) and 94% (88%-97%) (P > .05). In this porcine model, PE were usually seen as parenchymal perfusion defects (98%) with MR angiography and as occlusive emboli (100%) with CT. CONCLUSION: MR angiography is as sensitive as CT for the detection of small PE in a porcine model.  相似文献   

5.
Multiphase contrast-enhanced CT of the liver with a multislice CT scanner   总被引:2,自引:0,他引:2  
Our objective was to assess the effects of the injection rate of contrast material and of a 5% dextrose flush on enhancement in multiphase hepatic CT using a multislice CT scanner. Most patients had chronic hepatitis and/or liver cirrhosis. One hundred eighty examinations, in which two sequential acquisitions were performed during a single breath-hold followed by third- and fourth-pass acquisitions, were randomized into four protocols: contrast injection at 0.1 ml/kg body weight s–1 over 21 s without and with a 30-ml flush in groups 1 and 2, respectively, and contrast injection at 0.07 ml/kg body weight s–1 over 30 s without and with a flush in groups 3 and 4, respectively. Contrast enhancement in each acquisition was measured in the aorta, portal vein, and liver. The visualization of hepatic arterial branches was scored by visual assessment. The highest aortic enhancement was observed in the first-pass acquisition in all groups. At the higher injection rate (groups 1 and 2), aortic enhancement in the first-pass acquisition was significantly more intense, whereas portal venous and hepatic enhancement was significantly less intense. The use of a flush considerably improved aortic enhancement at the beginning of the second-pass acquisition. In the visual assessment of hepatic arterial branches, the protocols with the higher injection rate received significantly higher grades. Multislice CT permits the entire liver to be imaged during an almost exclusively arterial phase by shortening the injection duration for a given volume of contrast material. Electronic Publication  相似文献   

6.
Curative therapies for hepatocellular carcinoma(HCC),such as resection and liver transplantation,can only be applied in selected patients with early tumors.More advanced stages require local or systemic therapies.Resection of HCC offers the only hope for cure.Even in patients undergoing resection,recurrences are common.Chemoembolization,a technique combining intraarterial chemotherapy with selective tumor ischemia,has been shown by randomized controlled trials to be efficacious in the palliative setting.There is now renewed interest in transarterial embolization/transarterial chemoembolization(TACE) with regards to its use as a palliative tool in a combined modality approach,as a neoadjuvant therapy,in bridging therapy before transplantation,for symptomatic indications,and even as an alternative to resection.There have also been rapid advances in the agents being embolized trans-arterially(genes,biological response modifiers,etc.).The current review provides an evidence-based overview of the past,present and future trends of TACE in patients with HCC.  相似文献   

7.
A necrotic liver abscess model was studied with magnetic resonance (MR) imaging at 1.5 T before and after intravenous administration of gadoteridol at doses of 0.1, 0.25, and 0.5 mmol/kg in 24 rabbits. Enhancement characteristics and lesion delineation were assessed with both breath-hold and non-breath-hold imaging techniques. Lesion delineation, as assessed both by signal intensity measurements and evaluations by two image readers blinded to imaging technique, was greatest on high-dose (0.5 mmol/kg) breath-hold images. Lesion rim enhancement was seen consistently only on postcontrast images obtained at a dose of 0.5 mmol/kg and progressed with time after injection of contrast material.  相似文献   

8.
We compared two imaging techniques, spiral CT arterial portography (CTAP) and MR imaging, for diagnostic accuracy, procedural cost, and effect on management of 26 patients referred for hepatic surgery for suspected limited malignant liver disease. CTAP and MR imaging were done within a 1-week period (19 within 24 hours); the results of the studies were interpreted prospectively by separate reviewers. Surgical data were evaluated in conjunction with imaging data in 10 patients. Lesion detection and segmental involvement were determined and sensitivity and specificity were calculated. Procedural cost was determined from hospital billing codes. Effect on patient management was determined by the referring oncologic surgeon. CTAP and MR imaging showed 185 and 176 true-positive malignant lesions, 15 and zero false-positive malignant lesions, zero and 18 true-negative malignant lesions, and 13 and 22 falsenegative malignant lesions, respectively. CTAP and MR imaging showed 107 and 105 true-positive segments, 11 and zero false-positive segments, 80 and 91 true-negative segments, and four and six false-negative segments, respectively. There was a significant difference in specificity of segmental involvement between MR imaging (1.0 ± 0) compared with CTAP (0.88 ± 0.05), P=.03. Total procedural cost was $3,499 for CTAP and $1,224 for MR imaging. CTAP findings did not change patient management over MR imaging findings in any patient, whereas MR imaging findings resulted in a change in patient management over CTAP findings in seven patients (P=.015). The results of our study suggest that MR imaging has higher diagnostic accuracy and greater effect on patient management than CTAP does and is 64% less expensive.  相似文献   

9.
Summary This paper describes a prototype system to aid in the radiological interpretation of CT scan images of patients with cerebral disease. The system is able to provide guidance, both on diagnosis and the need for enhancement.  相似文献   

10.
Purpose The goal of the study is to evaluate utility of contrast enhanced ultrasound (US) with carbon dioxide microbubbles in evaluation of hepatic lesions.Methods Twenty eight patients with single or multiple t hepatic lesions (11 hepatocellular carcinoma, 8 hemangiomas, 5 metastases, 1 adenoma, 1 focal nodular hyperplasia, 2 regenerative nodules) were examined. US exam was performed during intraarterial injection of 10 ml of CO2 through the same catheter employed for liver arteriography. The US exam was videotaped in its salient phases. Characteristics of enhancement were evaluated and correlated with histological findings or patient follow up.Results Sonographic angiography clearly demonstrated vascularization of the lesions. Hepatocellular carcinoma, hemangioma, metastases, focal nodular hyperplasia, and regenerative nodules had very characteristic patterns. The injection of CO2 allowed detection of small additional nodules.Conclusion Sonographic angiography can improve characterization and staging of hepatic tumors. Low cost and the simplicity of the technique should encourage further experimentation.  相似文献   

11.
RATIONALE AND OBJECTIVES: The purpose of this study is to investigate the use of computer-extracted features of lesions imaged by means of two modalities, mammography and breast ultrasound, in the computerized classification of breast lesions. MATERIAL AND METHODS: We performed computerized analysis on a database of 97 patients with a total of 100 lesions (40 malignant, 40 benign solid, and 20 cystic lesions). Mammograms and ultrasound images were available for these breast lesions. There was an average of three mammographic images and two ultrasound images per lesion. Based on seed points indicated by a radiologist, the computer automatically segmented lesions from the parenchymal background and automatically extracted a set of characteristic features for each lesion. For each feature, its value averaged over all images pertaining to a given lesion was input to a Bayesian neural network for classification. We also investigated different approaches to combine image-based features into this by-lesion analysis. In that analysis, mean, maximum, and minimum feature values were considered for all images representing a lesion. We considered performance by using a leave-one-lesion-out approach, based on image features from mammography alone (two to five features), ultrasound alone (three to four features), and a combination of features from both modalities (three to five features total). RESULTS: For the classification task of distinguishing cancer from other abnormalities in a lesion-based analysis by using a single modality, areas under the receiver operating characteristic curves (A(z) values) increased significantly when the computer selected the manner (mean, minimum, or maximum) in which image-based features were combined into lesion-based features. The highest performance was found for lesion-based analysis and automated feature selection from mean, maximum, and minimum values of features from both modalities (resulting in a total of four features being used). That A(z) value for the task of distinguishing cancer was 0.92, showing a statistically significant increase over that achieved with features from either mammography or ultrasound alone. CONCLUSION: Computerized classification of cancer significantly improved when lesion features from both modalities were combined. Classification performance depended on specific methods for combining features from multiple images per lesion. These results are encouraging and warrant further exploration of computerized methods for multimodality imaging.  相似文献   

12.
目的 探讨CT和MR两种影像技术在肝癌冷冻消融治疗中的价值.方法 121例肝癌患者共131个病灶行氩氦刀治疗,其中男73例、女48例,平均年龄(60±8)岁,61例行CT引导下冷冻消融、60例行MR引导下冷冻消融.CT引导采用大孔径16层扫描仪,带有CT透视功能;MR引导采用0.35 T开放式扫描仪,辅助红外导航仪,应用快速梯度回波和快速自旋回波扫描序列.氩氦刀采用MR兼容冷冻系统,冷冻探针为17 G、外径1.47 mm.根据病灶位置、形态、毗邻结构,采用多针组合,适形冷冻.冷冻消融模式为2次冻-融循环消融法,术中间断扫描监测病灶消融情况.以平均扫描时间、病灶显示及冰球监测、肿瘤消融有效率、并发症、生存时间为评价指标,肿瘤消融有效率的比较采用x2检验.结果 CT引导平均扫描时间为(5.6±1.8)min,MR引导平均扫描时间(22.0±2.6)min.CT在病灶精细程度及肋骨等结构的显示方面优于MR;CT扫描中金属探针可以产生伪影,难于显示碘油栓塞后病灶的冰球形成情况.MR在显示、导引和监测邻近膈肌、肝门、胆囊区等特殊部位病灶方面优于CT;而且MR不受高密度栓塞剂及金属探针的影响,在显示病灶、监测冰球形成和病灶消融情况等方面优于CT.但是,MR扫描时间长,低场强开放式MR图像质量不及CT.两组病例随访12个月,CT引导组和MR引导组1年生存率分别为90.2%(55/61)、90.0%(54/60),术后1个月两组病例肿瘤消融有效率分别为75.4%(46/61)、83.4%(50/60).(x2检验=4.4056,P<0.05).结论 CT引导快速直接,尤其对穿刺路径中的肋骨等结构显示优于MR.MR具有多平面成像对显示病灶与肿瘤的关系,监测治疗效果方面优于CT,尤其在显示、导引和监测邻近膈肌、肝门、胆囊区等特殊部位病灶的穿刺消融优于CT引导.  相似文献   

13.
RATIONALE AND OBJECTIVES: The purpose of this study was to determine whether the interval change in hepatic colorectal metastases as assessed with serial computed tomographic (CT) scans without contrast material enhancement differs from that as assessed using serial, portal dominant phase, contrast-enhanced CT scans. MATERIALS AND METHODS: Unenhanced and contrast-enhanced abdominal CT scans were obtained in 28 patients. Three radiologists separately reviewed serial unenhanced and contrast-enhanced studies to assess the interval change in liver metastases. These radiologists recorded total number of lesions, bidimensional measurements of the largest lesions (as many as three), and overall impressions regarding the interval change (none, worse, or better). RESULTS: Among the 84 judgments (28 patients x 3 radiologists), comparisons of unenhanced and contrast-enhanced CT studies were concordant in 60 assessments (71%). Nineteen (23%) showed mild disagreement. Of these, contrast-enhanced CT studies demonstrated disease stability when unenhanced CT studies demonstrated otherwise in 11 judgments, whereas unenhanced CT studies demonstrated stability when contrast-enhanced CT studies demonstrated otherwise in eight assessments. Furthermore, of the five marked disagreements, two resulted from a conclusion of interval improvement on unenhanced CT studies and a conclusion of interval worsening on contrast-enhanced CT studies, whereas three demonstrated the opposite. Neither set of serial CT studies systematically resulted in under- or overestimation of disease progression (McNemar Q test, P < .25). CONCLUSION: The authors found no consistent pattern to demonstrate that serial unenhanced or contrast-enhanced CT studies resulted in over- or underestimation of disease progression.  相似文献   

14.
肝移植术后胆道并发症的多层螺旋CT诊断   总被引:1,自引:0,他引:1  
目的 评价MSCT在诊断肝移植术后胆道并发症中的价值.方法 83例原位肝移植术后患者因临床和生化检查可疑胆道并发症行MSCT增强检查.胆道并发症的确诊依据为直接胆道造影69例、移植肝病理11例、肝管空肠吻合术3例.分析CT诊断胆道并发症的能力,计算其敏感度、特异度、准确度、刚性预测值和阴性预测值,并用x2检验比较胆管吻合口狭窄和非吻合口狭窄的CT特征.结果 83例中,62例(74.7%)证实有胆道并发症,其中胆管吻合口狭窄32例,非吻合口狭窄21例,胆管结石16例(12例合并胆管狭窄),胆总管吻合口漏5例,胆汁瘤4例(合并胆管狭窄)、胆源性肝脓肿2例(合并胆管狭窄).CT诊断胆管狭窄的敏感度、特异度、准确度、阳性预测值、阴性预测值分别为90.6%、86.7%、89.2%、92.3%和83.9%.CT对胆管结石、胆总管吻合口漏、胆汁瘤、胆源性肝脓肿均能正确诊断,无漏诊和误诊.非吻合口狭窄表现为胆管不均匀扩张的发生率(71.4%,15/21)显著高于吻合口狭窄者(25.0%,8/32;P<0.01),而肝外胆管扩张(33.3%,7/21)和胆管均匀扩张(14.3%,3/21)的发生率均显著低于吻合口狭窄者(84.4%,27/32和68.8%,22/32;P<0.01).非吻合口狭窄肝动脉缺血的发生率(66.7%,14/21)明显高于吻合口狭窄者(15.6%,5/32;P<0.01).结论 MSCT对诊断肝移植术后胆道并发症具有重要价值,还可初步诊断胆管狭窄类型;肝动脉缺血是胆管非吻合口狭窄的重要原因.  相似文献   

15.
Twenty consecutive cancer patients with a solitary hepatic metastasis detected with dynamic contrast-material—enhanced computed tomography (CT) who were considered for hepatic resection underwent magnetic resonance (MR) imaging within 18 days after CT. Histologic confirmation was obtained in all lesions. CT depicted 20 solitary lesions. MR imaging showed a solitary lesion in 14 patients, two lesions in three patients, and more than two lesions in three patients, for a total of 37 lesions. Twenty-three lesions less than 2 cm in diameter were missed with CT, and six lesions less than 1.3 cm in diameter were missed with MR imaging. MR imaging was superior to CT in the detection of hepatic metastases on a patient-by-patient basis (P <.01). The results suggest that MR imaging is superior to dynamic contrast-enhanced CT for the detection of hepatic metastases.  相似文献   

16.
Use of CT in the evaluation of primary cardiac tumors   总被引:3,自引:0,他引:3  
Two cases of primary cardiac sarcomas diagnosed with CT are presented. CT demonstrated the origin, extent, and potential pathology of the tumors. In both cases CT provided more specific information for diagnosis and treatment planning than the 2D echocardiography. The advantages of CT in the detection of cardiac tumors as well as its potential advantages over 2D echocardiography are also discussed.  相似文献   

17.
Diagnosis of fatty liver with MR imaging.   总被引:1,自引:0,他引:1  
The diagnosis of fatty liver with magnetic resonance (MR) imaging was evaluated in experimental rat models of simple fatty infiltration and fatty liver with hepatocellular injury. T1 and T2 were measured ex vivo and correlated with the histologic degree of fatty infiltration. Enhancement of fatty liver with four different cells-specific contrast agents was studied with ex vivo relaxometry and in vivo MR imaging. Quantitative analysis of conventional and chemical shift MR images was correlated with biochemically determined fat content of the liver. Diet-induced simple fatty infiltration of the liver caused a decrease in T1 of 15%, whereas the T1 of L-ethionine-induced fatty liver with hepatocellular injury increased by 12%. T2 showed a positive correlation with the degree of fatty infiltration in both models. Cell-specific hepatobiliary contrast agents showed the same liver uptake and relaxation enhancement in fatty livers as in normal livers. Conventional T1-weighted images and chemical shift images showed good correlation (r = .83 and .80, respectively) between signal intensity and the degree of fatty infiltration. However, only chemical shift imaging was reliable in the diagnosis of fatty liver.  相似文献   

18.
Fifty-three consecutive patients with 61 solid or complex non-fat-containing renal masses compatible with renal cancer were examined with contrast-enhanced computed tomography (CT) and magnetic resonance (MR) imaging with pre- and postcontrast FLASH (fast low-angle shot) and fat-suppressed spin-echo sequences. CT and MR imaging were performed within a 1-month interval. CT and MR images were prospectively interpreted. Tumor detection and staging were determined in all patients. CT and MR imaging enabled detection of 54 and 58 of 61 renal tumors, respectively. CT and MR imaging showed 34 and 35 of 38 histologically proved renal tumors, respectively, in 31 patients. Tumor size on CT and MR images demonstrated good correlation and correlated well with the size of pathologic specimens of 34 of 38 resected tumors detected with CT and MR imaging (r =.99). Of the 31 tumors in 31 patients who underwent surgical resection, 24 were correctly staged with CT and 29 with MR imaging. CT and MR imaging both enabled correct staging of four of five additional tumors with biopsy proof of tumor stage. A moderate difference in staging was observed between CT and MR imaging (P =.05). CT showed 13 and MR imaging 15 of 15 tumor thrombi. CT and MR imaging both showed 11 of 11 cases of adenopathy. The results suggest that MR imaging is moderately better than CT for the detection and staging of renal cancer.  相似文献   

19.
Cystic renal tumors represent a variety of lesions in which both solid and liquid components coexist. These lesions may be either benign or malignant and include the multilocular cystic nephroma (MCN), the renal cell carcinoma (RCC), and the papillary adenocarcinoma (PAC). The MCN is a rare neoplasm formed of multiple loculated cystic masses divided by septa. The tumor is benign, although there are some rare reports of malignant cases. The RCC and the PAC may appear with cystic patterns. This is rather uncommon for the RCC, which inside has a unilocular or multilocular cystic appearance, if the necrotic component is large. PAC is an infrequent renal tumor, which has a greater tendency to appear as a large mass with a unilocular large cystic space. The ultrasonography (US) and computed tomographic (CT) features of 27 cystic tumors are presented. Both US and CT allowed the recognition of the cystic components, the septa, and the vegetations. The two imaging techniques made it possible to distinguish the tumors into “unilocular” and “multilocular” masses: the former correspond to RCC and PAC, the latter to MCN and RCC. CT added some information on calcified or partially calcified tumors. CT more than US enabled the differentiation between the malignant RCC and the benign MCN for which conservative surgery may be indicated. The two techniques did not allow the differentiation between RCC and PAC, which has different prognostic behavior.  相似文献   

20.
The computed tomographic (CT) and magnetic resonance (MR) appearance of a retrovesical leiomyoma in a male patient is presented. Although leiomyomas are common lesions, the location within the retrovesical pouch is very unusual.  相似文献   

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