State-of-the-art HR-US imaging findings of the most frequent musculoskeletal soft-tissue tumors

High resolution ultrasound (HR-US) including color Doppler ultrasound (CD-US), power Doppler ultrasound (PD-US), and spectral wave analysis (SWA), is a broadly available, non-invasive and relatively low-cost modality without ionizing radiation. It is increasingly used for initial assessment of an ambiguous musculoskeletal soft-tissue lesion and for sonographically guided core biopsy. The aim of this review is to provide sonographic findings of the most frequent benign and malign soft-tissue lesions. By this essay, we can show that combined with clinical features, with information on tumor-localization and patient age, many musculoskeletal lesions may be successfully characterized by HR-US. In contrast, a mere morphologic assignment of some fibrous tumors and malignant lesions remains often impossible; however, certain CD-US signs such as anarchic vascular architecture or arteriovenous shunting may be very helpful indicators for malignancy. HR-US offers a simple, quick, and reliable first-line examination of musculoskeletal soft-tissue lesions and may have an important role in the diagnostic work-up followed by magnetic resonance or multimodality imaging and guided core biopsy.     

Solid breast masses: neural network analysis of vascular features at three-dimensional power Doppler US for benign or malignant classification

PURPOSE: To retrospectively evaluate the accuracy of neural network analysis of tumor vascular features at three-dimensional (3D) power Doppler ultrasonography (US) for classification of breast tumors as benign or malignant, with histologic findings as the reference standard. MATERIALS AND METHODS: This study was approved by the local ethics committee; informed consent was waived. Three-dimensional power Doppler US images of 221 solid breast masses (110 benign, 111 malignant) were obtained in 221 women (mean age, 46 years; range, 25-71 years). After narrowing down vessels to skeletons with a 3D thinning algorithm, six vascular feature values--vessel-to-volume ratio, number of vascular trees, total vessel length, longest path length, number of bifurcations, and vessel diameter-were computed. A neural network was used to classify tumors by using these features. Independent-samples t test and receiver operating characteristic (ROC) curve analysis were used. RESULTS: Mean values of vessel-to-volume ratio, number of vascular trees, total vessel length, longest path length, number of bifurcations, and vessel diameter were 0.0089 +/- 0.0073 (standard deviation), 26.41 +/- 14.73, 23.02 cm +/- 19.53, 8.44 cm +/- 10.38, 36.31 +/- 37.06, and 0.088 cm +/- 0.021 in malignant tumors, respectively, and 0.0028 +/- 0.0021, 9.69 +/- 6.75, 5.17 cm +/- 4.78, 1.68 cm +/- 1.79, 6.05 +/- 7.55, and 0.064 cm +/- 0.028 in benign tumors, respectively (P < .001 for all six features). Area under ROC curve (A(z)) values of the six features were 0.84, 0.87, 0.87, 0.82, 0.84, and 0.75, respectively. Accuracy, sensitivity, specificity, and positive and negative predictive values were 85% (187 of 221), 83% (96 of 115), 86% (91 of 106), 86% (96 of 111), and 83% (91 of 110), respectively, with A(z) of 0.92 based on all six feature values. CONCLUSION: Three-dimensional power Doppler US images and neural network analysis of features can aid in classification of breast tumors as benign or malignant.     

Does Doppler analysis of musculoskeletal soft-tissue tumours help predict tumour malignancy?

AIM: To investigate whether analysing vascularity of soft-tissue tumours on ultrasound assists differentiating benign from malignant tumours. MATERIALS AND METHODS: One hundred and forty-eight vascular soft-tissue tumours in 148 patients (88 males, mean age 45.6 years) were studied. Final diagnosis was established histologically in 95 (64%) of cases. For each tumour, three-colour Doppler imaging features (vascularity, vascular density, vascular organization) and 13 pulsed Doppler (spectral analysis) parameters were assessed. Data analysis was performed to isolate optimal discriminatory criteria for differentiating benign from malignant tumours. RESULTS: Significantly more benign soft-tissue tumours had an organized vascular pattern on colour Doppler imaging. If the vascular pattern is organized, this is a good indicator of tumour benignity. However, this pattern was apparent in less then one-third of the soft-tissue tumours. Benign tumours also had significantly higher minimum end diastolic velocity (EDVmin) and lower mean ratio of resistive index (RImean) than malignant soft-tissue tumours, though considerable overlap existed between the two groups. CONCLUSION: Colour Doppler imaging analysis of soft-tissue tumours is of limited value when differentiating benign from malignant tumours. If an organized vascular pattern is present, the tumour is more likely to be benign. Flow characteristics were not specific enough to be applicable in clinical practice.     

Computer-assisted quantitative assessment of power Doppler US: effects of microbubble contrast agent in the differentiation of breast tumors

RATIONALE AND OBJECTIVES: To objectively quantify the effects of a microbubble contrast agent to differentiate breast tumors with power doppler ultrasound and to compare these results with color doppler ultrasound (CD US). METHODS: In 47 patients a microbubble contrast agent was injected intravenously. Computer-assisted quantitative assessment of the color pixel density was performed to evaluate the increase in Doppler signals. Results were compared to previously published results of a color Doppler ultrasound study. RESULTS: Peak color pixel density at contrast-enhanced power Doppler ultrasound was higher for carcinomas than for benign tumors (P < 0.03). Time to peak enhancement was shorter in carcinomas than in benign tumors (P < 0.01). For both parameters, diagnostic accuracy of power Doppler ultrasound was 69 and 78%, and for color Doppler ultrasound 62 and 76%, respectively. CONCLUSIONS: Quantitative assessment of contrast-enhanced power Doppler ultrasound showed significant differences in malignant and benign breast tumors. Diagnostic accuracy of contrast-enhanced power Doppler ultrasound was higher compared to color Doppler ultrasound.     

Power Doppler US patterns of vascularity and spectral Doppler US parameters in predicting malignancy in thyroid nodules

AIM: The purpose of this study was to determine whether spectral Doppler ultrasound (US) parameters, including resistive index (RI) and maximal systolic velocity (MSV), or vascular pattern can be used to distinguish malignant from benign thyroid nodules. MATERIALS AND METHODS: We prospectively examined 169 thyroid nodules in 134 patients undergoing sonographically guided fine-needle aspiration biopsy (FNAB). Vascularity as determined by power Doppler US imaging was defined as absent, perinodular alone, or intranodular. For each nodule, the RI and MSV values were recorded as the average of the recordings obtained. Results of the FNAB and surgical pathological examination, if available, were used as a proof of final diagnosis to categorize all nodules as benign or malignant. RESULTS: Seven nodules were excluded from study because of non-diagnostic FNAB results due to hypocellular or insufficient cytological material. Of the remaining nodules, nine were malignant (all confirmed at surgery) and 153 were benign. Of the 145 nodules with intranodular vascularity, nine (6.2%) were malignant and the remaining 136 (93.8%) were benign. The malignant nodules had a mean RI of 0.60 on intranodular and 0.58 on perinodular arteries. These values were not significantly higher than those associated with benign nodules (RI=0.57 and RI=0.56, respectively). Malignant nodules had a mean MSV of 20.4cm/s on intranodular and 35.3cm/s on perinodular arteries that were also not significantly different from those associated with benign nodules (p>0.05). CONCLUSION: The results of this study indicate that Doppler US characteristics including vascular pattern, RI and MSV are not useful parameters for distinguishing malignant from benign thyroid nodules. Therefore, Doppler US characteristics including vascular pattern, RI and MSV values of thyroid nodules can not be used as a diagnostic method to determine which nodules should undergo FNAB.     

Contrast-enhanced color Doppler US in malignant portal vein thrombosis

Purpose: To assess the role of contrast-enhanced color Doppler US in the differential diagnosis of benign and malignant portal vein thrombosis.Material and Methods: Fifty-six patients with portal vein thrombosis underwent color and power Doppler US examination before and after i.v. injection of galactose-palmitic acid suspension. The criterion for diagnosing the presence and extension of thrombosis was the lack of visualization of portal vein flow in a segment of the portal vein. The criterion for diagnosing malignant portal vein thrombosis was the detection of pulsatile arterial flow, either hepatopetal or hepatofugal, in the thrombus. The US data were correlated with the types of portal vein thrombosis.Results: Among the 56 patients, there were 40 benign and 16 malignant portal thromboses. Unenhanced Doppler US detected continuous blood flow in 24 benign thromboses and pulsatile in 3 malignant thromboses. No flow, either continuous or pulsatile, was detected in 16 cases with benign thrombosis and in 13 cases with malignant thrombosis. Contrast-enhanced Doppler US allowed to assess pulsatile flow in 15 cases with malignant thrombosis (94%). The use of pulsatile flow as diagnostic criterion of malignant thrombosis yielded a sensitivity of 57% and a specificity of 95% with conventional Doppler US, whereas contrast-enhanced US achieved a sensitivity of 94% and a specificity of 100%.Conclusion: Contrast-enhanced Doppler US is a reliable diagnostic tool for assessing malignant portal vein thrombosis.     

高频彩色多普勒超声在乳腺肿瘤诊断中的应用价值

目的探讨高频彩色多普勒超声对鉴别乳腺良恶性肿块的应用价值。方法对86例经手术病理确诊的乳腺疾病患者（56例良性,30例恶性）进行术前彩超检查,对比性分析了两组间高频声像图、彩色多普勒血流成像（CDFI）、病灶内血流Adler分级、阻力指数（RI）、峰值流速（PSV）的差异。结果乳腺良恶性肿块声像图鉴别以肿块边界及形态特征最重要,彩色多普勒显示乳腺癌内的血流较良性肿块明显丰富（P〈0．05）,乳腺癌的血管分布异常、频谱多普勒示肿块内动脉血流PSV、RI也是显著高于良性肿块且有显著性差异（P〈0．05）。结论综合分析和评价血流Adler分级及频谱多普勒各项血流动力学参数（PSV,RI）指标,有助于对乳腺良恶性肿块的鉴别。     

彩色多普勒超声对鉴别良恶性肾肿瘤的意义

目的探讨彩色多普勒超声（CDUS）对鉴别肾脏良、恶性肿瘤的意义。方法32例由手术病理证实的肾肿瘤患者（23例肾细胞癌，6例肾盂移行细胞癌，以及3例肾错构瘤）均经CDUS检查，首先分析其二维声像图特征，其次测量其肾动脉峰值血流速度及阻力指数，并将良、恶性患者的测量均值进行比较。结果肾脏良、恶性肿瘤具有不同的声像图特征，恶性肿瘤患者肾动脉峰值流速高于良性肿瘤患者，RI低于良性肿瘤患者。在32例中，CDUS定位诊断准确率为100％，2例恶性肿瘤被误诊为良性肿瘤，2例良性肿瘤被误诊为恶性肿瘤，CDUS的诊断敏感性为93．5％，特异性33．3％，准确性87．5％。结论CDUS，尤其是彩色多普勒血流显像（CDFI）技术对肾动脉血流参数的检测及对肿瘤内血流分布的评价，在鉴别肾脏良、恶性肿瘤中起重要作用。     

彩色多普勒能量图对卵巢肿瘤血流的研究

目的应用彩色多普勒能量图观察卵巢肿瘤的血流特征,以探讨其临床价值。材料与方法超声检查265例卵巢肿瘤患者293个病灶,所有病例均经手术获病理组织学证实。结果本组92.9％的卵巢癌显示肿瘤内血流,其中81.9％血流呈弥散分布。46.7％的卵巢良性肿瘤无血流显示,47.2％为包膜周边点状、带状单支规则血流。良恶性卵巢病灶的血流显示比较,相差极显著(P＜0.01)。结论彩色多普勒能量图能够直观地描述卵巢肿物的灌流状态,对于卵巢良恶性肿瘤的鉴别诊断有重要的参考价值。     

Characterization of benign and malignant solid breast masses in harmonic 3D power Doppler imaging

Purpose

The authors assessed the characteristics of benign and malignant solid breast tumors in harmonic three-dimensional (3D) power Doppler imaging and proposed decision models to classify benign and malignant breast tumors.

Materials and methods

A total of 86 malignant and 97 benign harmonic 3D power Doppler US images were analyzed. All the harmonic 3D power Doppler images were obtained using a Voluson730 US system (GE, Zipf, Austria) equipped with a RSP 6-12 transducer and tissue harmonic imaging modalities. Imaging analysis was performed using the Virtual Organ Computer-aided Analysis (VOCAL)-imaging program. Histogram indices, the vascularization index (VI), flow index (FI) and vascularization-flow index (VFI), were calculated for the intra-tumor and for shells with an outside thickness of 3 mm surrounding the breast tumors. The receiver operating characteristic (ROC) curves were calculated to estimate the diagnostic performances.

Results

The results revealed that the choice of decision model comprised the parameters of patient age, intra-tumor VI, and tumor volume to classify benign and malignant breast tumors. The area under the ROC curve (Az) was 0.910, accuracy was 81.4%, and sensitivity and specificity were 81.4% and 81.4%, respectively. The parameter intra-tumor VI was the choice for all of the histogram indices in differentiating between malignant and benign lesions.

Conclusion

The decision model, which was composed of patient age, tumor volume and intra-tumor VI, and a cut-off value for intra-tumor VI at the upper end of patient age and tumor volume, was recommended in clinical application.     

Nonpalpable breast lesions: evaluation with power Doppler US and a microbubble contrast agent-initial experience

PURPOSE: To evaluate power Doppler ultrasonography (US) performed with a microbubble US contrast agent in the differentiation of nonpalpable breast lesions. MATERIALS AND METHODS: Fifty nonpalpable breast lesions in 50 patients were prospectively evaluated with power Doppler US before and after injection of the contrast agent SH U 508A. Lesion vascularity and the morphology of vessels on US scans were analyzed and were correlated with histologic results. RESULTS: Surgical excision revealed 22 cancers and 28 benign lesions. At nonenhanced power Doppler US, eight (36%) of 22 cancers and four (14%) of 28 benign lesions were vascular. At contrast agent-enhanced power Doppler US, 21 (95%) cancers and six (21%) benign lesions were vascular (P <.001). Irregular vessels were seen in three cancers and one benign lesion at nonenhanced power Doppler US and in 11 cancers and one benign lesion at contrast-enhanced power Doppler US. By using the presence of vascularity in the mass as the diagnostic criterion for malignancy, the sensitivity, specificity, and positive and negative predictive values of power Doppler US changed from 36%, 86%, 67%, and 63%, respectively, to 95%, 79%, 78%, and 96% after contrast agent injection. CONCLUSION: Contrast-enhanced power Doppler US was superior to nonenhanced power Doppler US in the demonstration and characterization of tumor vascularity in nonpalpable breast lesions. Contrast-enhanced power Doppler US may be useful for the differentiation between nonpalpable breast cancers and benign tumors.     

Differentiation of benign and malignant tumors of the parotid gland: value of pulsed Doppler and color Doppler sonography

To establish criteria for the differentiation of benign and malignant tumors of the parotid gland using color Doppler sonography (CDS) and pulsed Doppler sonography (PDS) we examined 37 patients with parotid tumors by gray-scale ultrasound, CDS, and PDS. Tumor vascularization displayed by CDS was graded subjectively on a 4-point scale (0 = no vascularization, 3 = high vascularization). From the Doppler spectrum, the highest systolic peak flow velocity, the resistive index (RI), and the pulsatility index (PI) were calculated. There were 11 malignant and 26 benign tumors. Tumor vascularization by CDS was grade 0 or 1 in 88.5 % of benign lesions, whereas it was grade 2 or 3 in 82 % of malignant lesions (P < 0.0001). The highest systolic peak flow velocity was statistically significantly higher in malignant lesions than in benign lesions. Using a threshold systolic peak flow velocity of 25 cm/s, sensitivity was 72 % and specificity was 88 % for the detection of a malignant tumor. Evaluation of tumor vascularization by CDS and PDS cannot differentiate between benign and malignant parotid tumors with certainty. However, high vascularization and high systolic peak flow velocity in tumor vessels should raise the suspicion of malignancy, even if tumor morphology on gray-scale sonography indicates a benign lesion. Received 5 February 1998; Accepted 5 March 1998     

高频超声对乳腺小肿块鉴别诊断的价值

目的:评价高频超声二维征象及彩色多普勒血流指标在乳腺小肿块鉴别诊断中的价值。方法:使用高频超声诊断仪观察196个长径小于2 cm的乳腺肿块的二维超声特征(包括病灶形态,病灶内部,病灶后方有无衰减及有无微小钙化灶),然后使用彩色多普勒对病变进行多普勒血流参数测定(包括血流丰富度、PSV、RI、PI)。比较二维超声征象及彩色多普勒血流参数在乳腺良、恶性肿块中的差异并对其诊断敏感性、特异性加以分析。结果:病灶形态、病灶内部、病灶后方及有无微小钙化灶良、恶性病变间均有显著性差异。恶性肿块PSV、RI、PI值均明显高于良性肿块。结论:彩色多普勒超声血流参数测定对乳腺良、恶肿块的鉴别诊断具有重要的参考价值,与肿块的二维声像图征象相结合可提高乳腺肿块的超声诊断准确率。     

彩色多普勒超声对乳腺良恶性肿块的鉴别诊断价值

目的应用彩色多普勒血流显像（CDFI）观察乳腺肿块的血流特点，评价血流参数（PSV、R0对乳腺良、恶性肿块的鉴别诊断价值。方法运用CDFI检测73例的77个乳腺肿块，并与术后病理对照。对其中超声检测出血流的60个乳腺肿块观察血流特点并进行血流参数测定，比较乳腺良、恶性肿块的差异，同时对RI诊断的敏感性、特异性、阳性预测值、阴性预测值加以分析。结果乳腺恶性肿块的CDFI血流信号较良性肿块明显丰富。恶性肿块的PSV、RI值明显高于良性肿块CP〈O．05），以RI≥0．70诊断乳腺癌敏感性和特异性较高，分别为82．6％和80．95％。结论彩色多普勒血流显像及血流参数测定对乳腺良、恶肿块的鉴别诊断具有重要的参考价值。     

Radio-frequency ablation of VX2 rabbit tumors: assessment of completeness of treatment by using contrast-enhanced harmonic power Doppler US

PURPOSE: To assess contrast material-enhanced harmonic power Doppler and fundamental color Doppler ultrasonography (US) in the detection of residual viable tumor tissue after radio-frequency (RF) ablation in tumors embedded in fat. MATERIALS AND METHODS: Twenty-eight VX2 tumors were implanted into the retroperitoneum of 14 rabbits. Tumors were examined with contrast-enhanced fundamental color Doppler US and harmonic power Doppler US before and 10 minutes after RF ablation. Saline-enhanced RF ablation (30 mL/h) was performed over 10 minutes with 28-W RF power. Follow-up included repeat US examinations. Necropsies and histopathologic assessment were performed after detection of residual untreated tumor at US or 3 weeks after ablation. RESULTS: VX2 tumors reached a mean size of 21 mm +/- 9 (SD) (size range, 6-43 mm) 25 days after implantation. All tumors larger than 31 mm showed signs of central necrosis at US. Before ablation, intense vascularity was detected in all tumors with both contrast-enhanced US modes. Histopathologic assessment at the end of the follow-up period revealed local relapses due to incomplete ablation in 14 (50%) of 28 cases. Detection of residual tumor was missed in all cases with contrast-enhanced color Doppler US. Contrast-enhanced harmonic power Doppler US depicted residual flow in 12 of the 14 cases (sensitivity, 86%) in which local relapses occurred. There was a significant (P <.005, McNemar test) improvement in detection of residual tumor when the harmonic power Doppler mode was used. CONCLUSION: Contrast-enhanced harmonic power Doppler US has greater sensitivity than contrast-enhanced color Doppler US for detecting residual VX2 tumor following ablation. Therefore, contrast-enhanced harmonic power Doppler US may be a useful additional method for the detection of residual tumors after RF ablation.     

The role of colour flow Doppler in the investigation of the salivary gland tumour

AIMS: Ultrasound is a highly effective imaging technique to determine salivary gland tumours and may help to identify many benign lesions. The aim of this study is to evaluate whether colour Doppler is able to further differentiate the malignant tumour. METHODS: Fifty-six patients with salivary gland lesions were prospectively assessed using ultrasound imaging with colour flow and power Doppler. The peak systolic velocity (PSV) was measured and the pulsatility index (PI) and resistive index (RI) calculations were performed on the pulsed wave traces. The real time ultrasound morphology and the Doppler information were correlated with the histology. RESULTS: In 18 of the 56 patients, no internal colour flow or power Doppler changes could be detected. The real time ultrasound morphology diagnosed benign disease with sensitivity of 89.7% with specificity of 57.1%. The positive predictive value was 93.6%. There were no significant differences in the colour Doppler appearances in terms of vessel type or intratumour distribution which could separate benign from malignant conditions. However, there was statistical discrimination for PI and RI values (P = 0.0006, P = 0.0002, respectively). No malignant lesions were seen when the PI was less than 1.8 and RI was less than 0.8. The PSV was elevated in several cases (> 50 cm per s) but there was no statistical correlation with malignancy. CONCLUSION: The risk of malignancy increases by a third when the colour Doppler demonstrates increased intratumour vascular resistance (RI > 0.8 and PI > 1.8), with positive predictive value of 97.3% (sensitivity 75.5%, specificity 85.7%).Bradley, M. J. (2000). Clinical Radiology55, 759-762.     

Differential diagnosis of scrotal masses by ultrasound

Ultrasound is the mainstay for imaging of the scrotum. It is used primarily for determining the location and nature of palpable lesions and to demonstrate nonpalpable lesions. Scrotal US is characterized by high sensitivity in the detection of intrascrotal abnormalities and is a very good mode for differentiating testicular from paratesticular lesions. However, scrotal US is limited in determining whether a focal testicular lesion is benign or malignant. The limitations of gray-scale US in the assessment of an acute scrotum and in particular of testicular torsion have now been overcome by color-coded duplex sonography and power Doppler.     

Color Doppler in the echographic evaluation of breast nodules

The authors report on their experience with color Doppler sonography in the diagnosis of solid breast masses. Twenty-two patients were examined; breast masses were studied with B-mode US first, and then with color Doppler US to evaluate eventual tumor vascularization. Color Doppler US demonstrated only one vascular pole in histologically confirmed benign masses. On the contrary, in 92.8% of histologically confirmed malignant masses, color Doppler easily depicted 2 or more groups of nutritional arteries. Color Doppler makes the diagnosis of malignant masses easier, thus allowing, in the author's opinion, a reduction in the number of biopsies of solid breast masses clinically/mammographically detected. The use of color Doppler US is therefore suggested: the technique is noninvasive, fast, and easy and its widespread use would translate into advantages for both the patient and the clinician.     

Kinetics of a US contrast agent in benign and malignant adnexal tumors

PURPOSE: To evaluate the effects of a microbubble contrast agent on the power Doppler ultrasonographic (US) examination of adnexal tumors, with a special focus on the timing of the transit of the microbubble bolus. MATERIALS AND METHODS: Seventy patients who were suspected of having ovarian tumors were examined preoperatively with contrast material-enhanced US. Images obtained during a 5-minute examination were stored digitally, and the behavior of the contrast agent was evaluated objectively with measurement of the time-dependent image intensity at the region of interest with a computer program. A time-intensity curve in each case was derived and analyzed. The Mann-Whitney U test was used to compare intensity changes and tumor parameters in benign and malignant adnexal tumors. RESULTS: Both the baseline and maximum power Doppler intensities, as well as the absolute and relative (percent) rise in intensity, were significantly higher (P <.001) in malignant as compared with benign tumors. The arrival time was shorter (17.5 vs 22.5 seconds; P =.005) and the duration of contrast agent effect was longer (190.4 vs 103.6 seconds; P <.001) in malignant tumors than they were in benign tumors. The area under the time-intensity curve was significantly greater in malignant tumors compared with that in benign tumors (P <.001). CONCLUSION: After microbubble contrast agent injection, malignant and benign adnexal lesions behave differently in degree, onset, and duration of Doppler US enhancement.     

甲状腺良恶性结节的超声鉴别诊断

目的探讨甲状腺良恶性结节声像图表现及鉴别诊断。方法对经手术病理证实的60例甲状腺良性结节和21例恶性结节的超声二维及彩色多普勒血流声像图（CDFI）表现进行对比分析。结果良恶性结甲在形态,边界,内部回声,彩色血流分布,阻力指数,颈部淋巴结肿大等指标有统计学显著性差异。结论形态不规整,边界不清,内部不均匀低回声,微钙化,内部血流丰富而周边少或无血流,RI〉0．7等可以作为恶性结节的主要指标;不清晰、不完整、宽窄不一的晕环及颈部淋巴结肿大高度提示恶性;囊性结节可作为排除恶性指标。微小乳头状癌结节及良恶性并发的多源性结节常常会被误诊。