Vascular Morphology and Tortuosity Analysis of Breast Tumor Inside and Outside Contour by 3-D Power Doppler Ultrasound

This study aimed to evaluate morphologic and tortuous features of vessels inside and outside the tumor region on three-dimensional power Doppler ultrasonography (PDUS) in 113 breast mass lesions, including 60 benign and 53 malignant tumors. Compared with benign lesions, malignant breast lesions had significantly larger values of vascular morphologic and tortuous features and larger tumor sizes. The receiver operating characteristic curve analysis and Student's t-test were used to estimate the performance of a proposed classification system using 13 vascular features and tumor size selected by the neural network. Accuracy, sensitivity, specificity, positive predictive value, negative predictive value and the A_Z value of the diagnosis performance based on 14 features were 89.38% (101/113), 84.91% (45/53), 93.33% (56/60), 91.84% (45/49), 87.50% (56/64) and 0.9188, respectively. The three-dimensional PDUS morphologic and tortuous characteristics of blood vessels inside and outside breast mass lesions can be effectively used to classify benign and malignant tumors.     

Value of contrast-enhanced power Doppler sonography using a microbubble echo-enhancing agent in evaluation of small breast lesions

PURPOSE: The purpose of this study was to prospectively evaluate the usefulness of contrast-enhanced power Doppler sonography (PDUS) using a microbubble echo-enhancing agent in differentiating between malignant and benign small breast lesions. PATIENTS AND METHODS: Between July 1, 2000, and September 30, 2001, we performed gray-scale sonographic examination of patients in whom diagnostic sonography or screening mammography had revealed solid breast lesions measuring less than 2 cm in the largest dimension. The patients were then examined on PDUS before and after injection of a microbubble contrast agent. The sonographic findings for all 3 techniques, as well as the morphologic features of the Doppler signals for each patient before and after injection of the contrast agent on PDUS, were independently assessed. Each lesion was classified as "benign" or "malignant" on the basis of specific criteria for sonographic interpretation. A hemodynamic study was performed in which time-transit profiles of the Doppler signals on contrast-enhanced PDUS were generated using a computer-assisted program, and the results for each patient were compared with the findings of a histopathologic examination of surgical specimens. RESULTS: Thirty-six patients (35 women and 1 man) with a mean age of 43.5 years (range, 18-69 years) were evaluated. The tumors ranged from 4 to 19 mm in the largest dimension. Histopathologic examination revealed that 19 tumors were benign and 17 were malignant. For morphologic diagnosis of the malignant lesions, the sensitivity of gray-scale sonography was 100%, compared with 29% for PDUS without contrast enhancement. The specificity of gray-scale sonography was 47%, compared with 74% for PDUS without contrast enhancement. Contrast-enhanced PDUS had a sensitivity of 71% and a specificity of 58%. The diagnostic accuracy was 72% for gray-scale sonography, 53% for PDUS without contrast enhancement, and 64% for contrast-enhanced PDUS. The time-transit profiles of the hemodynamic study did not reveal a statistically significant difference in the accuracy rates of contrast-enhanced PDUS between benign and malignant breast lesions. CONCLUSIONS: Compared with PDUS without contrast enhancement, contrast-enhanced PDUS provides better visualization of the morphology of vascular Doppler signals that is characteristic of malignancy and therefore has a higher sensitivity and diagnostic accuracy, albeit a lower specificity. In differentiating between benign and malignant small breast lesions, contrast-enhanced PDUS can be helpful when used with gray-scale sonography and PDUS without contrast enhancement.     

Three-dimensional power doppler ultrasound is useful to monitor the response to treatment in a patient with primary papillary serous carcinoma of the peritoneum

To date, this is the first report to monitor changes of intratumor vascularization and the response to radiation and Cyberknife therapy in a patient with recurrent primary papillary serous carcinoma of the peritoneum by three dimensional (3D) power Doppler ultrasonography (PDUS). Transvaginal 3D PDUS detected a recurrent presacral tumor with abundant intratumor vascularity. Serial examinations of the tumor volume and serum CA-125 level were studied before, during, and 6 mo after therapy. Meanwhile, the intratumor blood flow was measured and expressed as vascularity indices. All of the tumor volume, intratumor vascularity indices and serum CA-125 level decreased progressively following therapy. A remaining lesion with nearly absent intratumor power Doppler signals suggested a scarring lesion posttreatment. Indeed, CT-guided tissue biopsy confirmed fibrotic change. 3D PDUS is useful to monitor the response to treatments and to differentiate residual tumors from lesions of scarring change posttreatment. It provides more accurate posttreatment information than pelvic computed tomography.     

阴道三维能量多普勒超声检测妊娠黄体血流对异位妊娠的诊断价值

目的 应用阴道三维能量多普勒超声对异位妊娠黄体和宫内妊娠黄体进行对比分析.方法 临床拟诊宫外孕患者30例,手术前行阴道超声检查.使用三维能量多普勒超声观察异位妊娠黄体血流分布,并对同期31例宫内妊娠黄体进行观察.采集三维能量多普勒血流图并测量相应的血管参数:血管形成指数(VI)、血流指数(FI)、血管形成-血流指数(VFI).比较异位妊娠黄体与宫内妊娠黄体血流分布及血管参数差异,评价其在异位妊娠鉴别诊断中的意义.结果 异位妊娠黄体血流信号低于宫内妊娠黄体,异位妊娠黄体血管参数VI、VFI值低于宫内妊娠黄体,差异均有统计学意义(P<0.05),异位妊娠黄体FI值低于宫内妊娠黄体,但无统计学差异.结论 阴道三维能量多普勒超声检测妊娠黄体血流信息,可为异位妊娠的诊断提供有价值信息.     

Power Doppler Ultrasonography in the Early Diagnosis of Primary/Idiopathic Adhesive Capsulitis: An Exploratory Study

Objective

The purpose of this exploratory study was to determine if increased vascularity in the rotator interval area of the glenohumeral joint capsule could be visualized with power Doppler ultrasonography (PDUS) in patients with a clinical diagnosis of early-stage adhesive capsulitis.

Methods

Demographic and clinical characteristics from a consecutive series of 41 patients diagnosed with early-stage adhesive capsulitis were recorded and examination with PDUS was undertaken. Images were reviewed by 3 musculoskeletal radiologists, and consensus was determined on the presence of increased signal in the rotator interval area.

Results

Consensus was achieved on the presence of increased signal in 12 (29%) of the 41 cases. Participants with an increased PDUS signal did not demonstrate a characteristic set of identifying features, suggesting that those with increased vascularity may not constitute a distinct subgroup.

Conclusion

This study found that some patients diagnosed with early-stage adhesive capsulitis demonstrated increased vascularity in the rotator interval area when examined with PDUS. These findings suggest that PDUS may have the potential to assist in the identification of increased vascularization in early stages of this disorder. Further research in the use of PDUS in diagnosing early-stage adhesive capsulitis is warranted.     

Computer-Aided Diagnosis for Breast Tumors by Using Vascularization of 3-D Power Doppler Ultrasound

This study assessed the accuracy of three-dimensional (3-D) power Doppler ultrasound in differentiating between benign and malignant breast tumors by using a support vector machine (SVM). A 3-D power Doppler ultrasonography was performed on 164 patients with 86 benign and 78 malignant breast tumors. The volume-of-interest (VOI) in 3-D ultrasound images was automatically generated from three rectangular regions-of-interest (ROI). The vascularization index (VI), flow index (FI) and vascularization-flow index (VFI) on 3-D power-Doppler ultrasound images were evaluated for the entire volume area, computer extracted VOI area and the area outside the VOI. Furthermore, patient's age and VOI volume were also applied for breast tumor classifications. Each ultrasonography in this study was classified as benign or malignant based on the features using the SVM model. All the tumors were sampled using k-fold cross-validation (k = 10) to evaluate the diagnostic performance with receiver operating characteristic (ROC) curves. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of SVM for classifying malignancies were 94%, 69%, 73%, 92% and 81%, respectively. The classification performance in terms of Az value for the ROC curve of the features derived from 3-D power Doppler is 0.91. This study indicates that combining 3-D power Doppler vascularity with patient's age and tumor size offers a good method for differentiating benign andmalignant breast tumors. (E-mail: ylhuang@thu.edu.tw (Y.-L.H.); darren_chen@cch.org.tw (D.-R.C.))     

Differentiation of breast masses using 3-D sonographic and echo-enhancer-based evaluation of the vascular pattern: initial experiences

To evaluate the potential of combined 3-D B-mode and color Doppler (CD) data sets in the differentiation of breast masses, in 50 patients with histologically proven solid breast lesions, 3-D datasets were acquired. A 3-D display was created and volume calculation of tumors, their periphery and vasculature was performed. Time-intensity curves of enhancement after administration of a contrast agent were analyzed. Volumetry of tumor vasculature yielded no significant differences between malignant and benign tumors regarding vascularization of the center (2.60 vs. 2.88%) and periphery (6.66 vs. 3.78%). Only the mean values for the rise time in the center of the tumor, fibroadenoma (FA): 5.7 s and ductal invasive carcinoma (DIC): 15.8s; p = 0.05, and the time to peak in the periphery, FA: 21.0 s and DIC: 31.6 s; p = 0.03, differed significantly. The 3-D ultrasound (US) technique was of no additional value in differentiating breast masses. The calculation of time-intensity curves after administration of a contrast agent may be helpful in differentiating FA and DIC.     

Vascularity of gastric carcinoma: evaluation using color Doppler ultrasonography

Purpose The purpose of this study was to investigate the vascularity of primary gastric cancer lesions using color Doppler ultrasonography.Methods We used color Doppler ultrasonography to study 78 patients with gastric cancer detected on B-mode ultrasonographic examination and 14 patients without gastric tumors but with a slightly thickened gastric wall that was also detected on B-mode ultrasound. The color Doppler signals of the gastric lesions were graded as (–), no color signals; (+), slight increase in number of color signals; and (++), an obvious increase in number of color signals. The vessel area outside the tumor area in the microscopic pathological specimens was also calculated.Results The color signals of 13 (18%) of the 71 gastric cancer patients were graded (–); those of 14 (20%) patients were graded (+); and those of 44 (62%) patients were graded (++). The color signals for 9 (65%) of 14 patients without gastric tumors were graded (–); those of 4 (28%) patients were graded (+), and those of 1 patient (7%) were graded (++). These differences were significant (P = 0.0002). The vessel count ratio in the microscopic pathologic specimens was also significantly higher in patients with an increased number of color signals than in those without an increased number of color signals (P = 0.002).Conclusion Color Doppler ultrasound showed increased vascularity in the gastric cancers in most of the subjects (82%, 58/71). Furthermore, color Doppler ultrasound also showed no increase in vascularity in most subjects (65%, 9/14) whose B-mode ultrasonograms showed thickened gastric walls but who did not have gastric cancer. Thus, color Doppler imaging may prove useful as a screening modality for gastric cancer.     

Early ovarian cancer: 3-D power Doppler

Transvaginal sonography plays an important role in the assessment of the morphology of ovarian lesions. However, the accuracy of the technique is limited due to the significant number of false-positive results. Color Doppler imaging and pulsed Doppler spectral analysis enable evaluation of ovarian tumor blood flow, analysis of the distribution of blood vessels, and quantitative measurement of blood flow velocity waveforms. These parameters increase the sensitivity and specificity of ultrasound evaluation of ovarian tumors. Unfortunately, there is no consensus as to which Doppler parameters and cutoff values are the most predictive of malignancy. Three-dimensional (3-D) power Doppler ultrasound provides a new tool to evaluate features of tumor vascularity. Three-dimensional ultrasound and 3-D power Doppler imaging in patients with “positive” findings on standard ultrasound tests, which encompass annual gray-scale transvaginal sonography followed by transvaginal color Doppler ultrasound in selected cases, represent a novel approach for early and accurate detection of ovarian cancer through screening. Combined evaluations of morphology and neovascularity by 3-D power Doppler ultrasound may improve early detection of ovarian carcinoma. Contrast-enhanced 3-D power Doppler sonography facilitates visualization of adnexal tumor vessels, which may aid in differentiating benign from malignant adnexal lesions.     

Analysis of Elastographic and B-mode Features at Sonoelastography for Breast Tumor Classification

The purpose of this study was to evaluate the accuracy of neural network analysis of elastographic features at sonoelastography for the classification of biopsy-proved benign and malignant breast tumors. Sonoelastography of 181 solid breast masses (113 benign and 68 malignant tumors) was performed for 181 patients (mean age, 47 years; range, 24–75 years). After the manual segmentation of the tumors, five elastographic features (strain difference, strain ratio, mean, median and mode) and six B-mode features (orientation, undulation, angularity, average gradient, gradient variance and intensity variance) were computed. A neural network was used to classify tumors by the use of these features. The Student's t test and receiver operating characteristic (ROC) curve analysis were used for statistical analysis. Area under ROC curve (Az) values of the three elastographic features– mean (0.87), median (0.86) and mode (0.83)–were significantly higher than the Az values for the six B-mode features (0.54–0.69) (p < 0.01). Accuracy, sensitivity, specificity and Az of the neural network for the classification of solid breast tumors were 86.2% (156/181), 83.8% (57/68), 87.6% (99/113) and 0.84 for the elastographic features, respectively, and 82.3% (149/181), 70.6% (48/68), 89.4% (101/113) and 0.78 for the B-mode features, respectively, and 90.6% (164/181), 95.6% (65/68), 87.6% (99/113) and 0.92 for the combination of the elastographic and B-mode features, respectively. We conclude that sonoelastographic images and neural network analysis of features has the potential to increase the accuracy of the use of ultrasound for the classification of benign and malignant breast tumors. (E-mail: rfchang@csie.ntu.edu.tw)     

The utility of transrectal real-time elastography in the diagnosis of prostate cancer

The aim of this study is to evaluate the diagnostic performance of transrectal real-time elastography (TRTE) to differentiate benign from malignant prostatic lesions, with pathologic diagnosis obtained by prostatic needle biopsy. Conventional gray scale transrectal ultrasonography (TRUS) and power Doppler ultrasonography (PDUS) were performed in 107 men who had elevated serum prostate-specific antigen level >4 ng/mL or abnormal findings on digital rectal examination. For baseline TRUS and PDUS imaging, the suspicion of carcinoma was scored using previously proposed five-point subjective scale. For TRTE imaging, we used newly adopted five-point subjective scale based on the degree and distribution of strain in relation to hypoechoic area, which simultaneously displayed on B-mode image. All patients underwent transperineal systematic 8-cores biopsies, as well as up to four cores of targeted biopsy from suspicious area by TRUS, PDUS and/or TRTE. The samples were diagnosed pathologically and compared with the findings of TRUS, PDUS and TRTE. Prostate cancer was detected in 40 (37%) of 107 patients. When a cutoff point of 3 (displaying focal asymmetric lesion without strain not related to hypoechoic lesion) was used, TRTE had 68% sensitivity, 81% specificity and 76% accuracy. TRTE was comparable with PDUS (70% sensitivity, 75% specificity and 73% accuracy) and had significantly higher sensitivity than TRUS (68% vs. 50%, p = 0.027). Combination of TRTE with PDUS increased sensitivity to 78%. The detection rate of directed biopsy from suspicious area in either TRTE or PDUS (TRTE+PDUS-directed biopsy) was 29% (31/107) by patient and was comparable with systematic biopsy (31%, 33/107, p = 0.86), whereas the detection rate of TRTE+PDUS-directed biopsy by core (55/111, 50%) was significantly higher than systematic biopsy (132/856, 15%, p < 0.0001). For assessing prostatic lesions, TRTE with B-mode image-based scoring had almost the same diagnostic performance as PDUS. Although TRTE+PDUS-directed biopsy detected comparable number of cancers with systematic biopsy, both techniques should be used supplementarily for minimizing the number of missing cancers.     

Sonographic features of nonpalpable breast cancer: a study based on ultrasound-guided wire-localized surgical biopsies

The purpose of this study is to investigate the correlation between surgicopathological findings and ultrasonic images of nonpalpable breast lesions. The study was composed of 220 nonpalpable breast lesions from 193 patients. The breast lesions were classified into soft tissue type (185 lesions) and calcification type (35 lesions). Of the 220 lesions, 62 (28%) were malignant. For soft tissue type lesions, the sonographic features of sound attenuation (p < 0.001) and irregular border (p < 0.001) were significantly associated with the malignant diagnosis. For soft tissue-type and calcification-type lesions, the presence of increased vascularity (p < 0.001) or calcification (p < 0.001) was significantly associated with the malignant diagnosis. Of the 164 breast lesions with corresponding mammograms, 37 of 74 mammographically identifiable lesions were pathologically malignant, as compared with 16 of 90 lesions with negative mammograms (p < 0.001). In our study, the more sensitive sonographic features for predicting malignancy were irregular border and increased vascularity (sensitivity 88% and 82%, respectively), whereas the features of sound attenuation and presence of calcifications were more specific (specificity 88% and 80%, respectively). In conclusion, ultrasound-guided wire localization of breast lesions is not only useful in assisting surgical biopsy, but the sonographic findings obtained by this procedure correlate with pathologic diagnosis.     

Computer-aided diagnosis for the classification of breast masses in automated whole breast ultrasound images

New automated whole breast ultrasound (ABUS) machines have recently been developed and the ultrasound (US) volume dataset of the whole breast can be acquired in a standard manner. The purpose of this study was to develop a novel computer-aided diagnosis system for classification of breast masses in ABUS images. One hundred forty-seven cases (76 benign and 71 malignant breast masses) were obtained by a commercially available ABUS system. Because the distance of neighboring slices in ABUS images is fixed and small, these continuous slices were used for reconstruction as three-dimensional (3-D) US images. The 3-D tumor contour was segmented using the level-set segmentation method. Then, the 3-D features, including the texture, shape and ellipsoid fitting were extracted based on the segmented 3-D tumor contour to classify benign and malignant tumors based on the logistic regression model. The Student’s t test, Mann-Whitney U test and receiver operating characteristic (ROC) curve analysis were used for statistical analysis. From the Az values of ROC curves, the shape features (0.9138) are better than the texture features (0.8603) and the ellipsoid fitting features (0.8496) for classification. The difference was significant between shape and ellipsoid fitting features (p = 0.0382). However, combination of ellipsoid fitting features and shape features can achieve a best performance with accuracy of 85.0% (125/147), sensitivity of 84.5% (60/71), specificity of 85.5% (65/76) and the area under the ROC curve Az of 0.9466. The results showed that ABUS images could be used for computer-aided feature extraction and classification of breast tumors. (E-mail: rfchang@csie.ntu.edu.tw)     

乳腺血供不对称性增加及邻近血管征鉴别诊断乳腺良恶性病变

目的 探讨乳腺血供不对称性增加及邻近血管征在鉴别乳腺良恶性病变中的价值。方法 回顾性分析经病理证实的102例乳腺病变患者的MR增强3D最大密度投影图像,比较乳腺血供不对称性增加、邻近血管征、上述两种征象均为阳性及其中任意一种征象为阳性在不同最大径病变及良恶性病变中的出现率;评价其鉴别乳腺良恶性病变的价值。结果 102例患者中,恶性病变58例,良性44例。乳腺血供不对称性增加及邻近血管征在恶性病变中的出现率高于良性病变,在最大径>2 cm病灶中的出现率高于最大径≤2 cm的病灶。以乳腺血供不对称性增加鉴别同侧乳腺良恶性病变的敏感度、特异度、阳性预测值(PPV)、阴性预测值(NPV)及ROC曲线下面积(AUC)分别为56.89%(33/58)、79.54%(35/44)、78.57%(33/42)、58.33%(35/60)及0.68;以邻近血管征诊断同侧乳腺恶性病变的上述指标分别为56.89%(33/58)、93.18%(41/44)、91.67%(33/36)、62.12%(41/66)及0.75;以上述两种征象均为阳性诊断恶性病变的敏感度、特异度、PPV、NPV及AUC分别为46.55%(27/58)、93.18%(41/44)、90.00%(27/30)、56.94%(41/72)及0.70;以其中任一征象阳性诊断恶性病变的敏感度、特异度、PPV、NPV及AUC分别为68.97%(40/58)、81.82%(36/44)、83.33%(40/48)、66.67%(36/54)及0.75。结论 乳腺血供不对称性增加及邻近血管征在鉴别乳腺良恶性病变中具有一定的参考价值。     

Computer algorithm for analysing breast tumor angiogenesis using 3-D power Doppler ultrasound

Angiogenesis provides blood supply for tumor expansion and also increases the opportunity for tumor cells to enter the blood or lymph circulation. Several proangiogenic factors as well as the contribution of the microenvironment to tumor-induced angiogenesis have been identified. Among these, vascular endothelial growth factor (VEGF) and the angiopoietin (Ang) family play a predominant role involved in the growth for endothelial cells. Tumor vessels are structurally and functionally abnormal because of an imbalance of these angiogenic regulators. In contrast to normal vessels, tumor vasculature is highly disorganized, tortuous and dilated, with uneven diameter and excessive branching. In other words, the morphologic features are likely to carry additional clues that, when used in conjunction with more established parameters, can improve the present diagnostic approaches. In our study, we present a new method that helps to capture the morphologic features from three-dimensional (3-D) power Doppler ultrasound (PDUS) images. After narrowing down the vessels into their skeletons using a 3-D thinning algorithm, we extracted seven features including vessel-to-volume ratio, number of vascular trees, number of bifurcation, mean of radius and three tortuosity measures, from the skeleton and applied a neural network to classify the tumors by using these features. In investigations into 221 solid breast tumors, including 110 benign and 111 malignant cases, the p values using the Student's t-test for all features were less than 0.05, indicating that the proposed features were deemed statistically significant. The A(Z) values for these seven features were 0.84, 0.87, 0.84, 0.75, 0.77, 0.79 and 0.69, respectively. The accuracy, sensitivity, specificity, and positive and negative predictive values were 80.09% (177 of 221), 80.18% (89 of 111), 80% (88 of 110), 80.18% (89 of 111) and 80% (88 of 110), respectively, with an A(Z) value of 0.89. The preliminary results show that the proposed method is feasible and has a good agreement with the diagnosis of the pathologists.     

Color Doppler sonographic findings in patients with transitional cell carcinoma of the bladder and renal pelvis.

The purposes of this study were (1) to evaluate the color Doppler sonographic findings in patients with transitional cell carcinoma of the bladder and renal pelvis, (2) to determine if color Doppler sonography could predict tumor grade and stage, and (3) to determine whether tumor vascularity is related to size. A total of 15 patients with 16 bladder transitional cell carcinomas and one patient with renal pelvic transitional cell carcinoma were evaluated prospectively with transabdominal color Doppler ultrasonography. The presence or absence of visible vascularity and the resistive index were correlated with tumor size, cytologic grade, and tumor stage. Statistical analysis was performed with Fisher's exact test. Seven (41%) of 17 tumors had visible vascularity: five (45%) of 11 high-grade transitional cell carcinomas were vascular, whereas two (33%) of six low-grade transitional cell carcinomas were vascular (P = 1.00). Three of five (60%) of the invasive lesions were vascular, but the vascularity was not predictive of tumor stage (P = 0.593). The vascular high-grade tumors tended to have more numerous and larger visible vessels than the vascular low-grade lesions. No tumor smaller then 23 mm was vascular, but the size of the tumor was not predictive of the vascularity (P = 0.1172). The resistive index was measurable in six tumors, but it was not predictive of grade or stage. Color Doppler ultrasonography is not helpful clinically in the evaluation of transitional cell carcinoma as tumor grade, stage, and size are not related to vascularity.(ABSTRACT TRUNCATED AT 250 WORDS)     

Detecting angiogenesis in breast tumors: comparison of color Doppler flow imaging with ultrasound-guided diffuse optical tomography

We investigated the correlation between color Doppler flow imaging (CDFI) and ultrasound (US)-guided diffuse optical tomography (DOT) for detection of breast tumor angiogenesis. Both CDFI and DOT were performed in 214 breast lesions scheduled for biopsy. The lesions were classified as vascular or nonvascular on CDFI and total hemoglobin concentration (THC) was measured by DOT. Sonographic results were correlated with the THC measurements. Pathologic examination showed 118 breast cancers and 96 benign breast masses. When vascularization on CDFI as a sign of malignancy and a cutoff of 140 μmol/L was used, the sensitivity, specificity and accuracy were 83.9, 50.0 and 68.7% for CDFI and 83.9, 66.7 and 76.2% for DOT, respectively. Thirteen (11.0%) nonvascular breast cancers presented high THC levels. Twenty-five (52.1%) vascular benign tumors demonstrated low THC levels. Mean THC did not differ significantly in malignancies with vascular or without vascular (228.14 ± 85.37 μmol/L vs. 191.42 ± 92.59 μmol/L; p > 0.05). Likewise, for benign lesions, the difference between THC values in vascular lesions and nonvascular lesions was not statistically significant (140.86 ± 79.63 μmol/L vs. 110.13 ± 85.05 μmol/L; p > 0.05). Our results suggest that the addition of DOT to CDFI could be helpful for characterizing CDFI nonvascular lesions that are suspicious for malignancy or vascular lesions that are probably benign.     

Breast cancer diagnosis using three-dimensional ultrasound and pixel relation analysis

Because ultrasound (US) imaging offers benefits compared with other medical imaging techniques, it is used routinely in nearly all hospitals and many clinics. However, the surface features and internal structure of a tumor are not easily demonstrated simultaneously using the traditional 2-D US. The newly developed three-dimensional (3-D) US can capture the morphology of a breast tumor and overcome the limitations of the traditional 2-D US. This study deals with pixel relation analysis techniques for use with 3-D breast US images and compares its performance to 2-D versions of the images. The 3-D US imaging was performed using a Voluson 530 scanner. The rectangular subimages of the volume-of-interest (VOI) were manually selected and the selected VOIs were outlined to include the entire extent of the tumor margin. The databases in this study included 54 malignant and 161 benign tumors. All solid nodules at US belong over C3 (probably benign) according to ACR BI-RADS category. All or some selected 2-D slices were used separately to calculate the diagnosis features for a 3-D US data set. We have proposed and compared several different methods to extract the characteristics of these consecutive 2-D images. As shown in our experiments, the diagnostic results were better than those of the conventional 2-D US. In the experiments, the area index Az under ROC curve of the proposed 3-D US method can achieve 0.9700 +/- 0.0118, but Az of the 2-D US is only 0.8461 +/- 0.0315. The p value of these two Az differences using z test is smaller than 0.01. Furthermore, we can find that the features from only several slices are enough to provide good diagnostic results if the adopted features are modified from the 2-D features.     

Large-Strain 3-D in Vivo Breast Ultrasound Strain Elastography Using a Multi-compression Strategy and a Whole-Breast Scanning System

Non-linear mechanical properties of breast tissue can be employed to diagnose and differentiate breast tumors. To obtain such non-linear mechanical properties, it is necessary to track tissue motion under large deformation. In this study, a multi-compression strategy was utilized to produce large tissue deformation, and a method to estimate 3-D motion of tissue under large deformation was introduced. Given multiple volumes of ultrasound data, the proposed method first estimates volume-to-volume incremental displacements using a 3-D region-growing motion-tracking method. Then, possible outliers among all incremental displacements are removed to avoid error accumulation. Once large displacement errors have been removed, all incremental displacements are registered together to obtain accumulated displacements under large tissue deformation (e.g., >10%). The proposed method was tested with one set of in vivo tumor-bearing ultrasound data acquired from a human subject. A total of 10 small-strain deformation steps were performed to obtain the final accumulated displacement field, in which the breast lesion and its surrounding were deformed by approximately 6% and 16%, respectively. The contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR) of the elasticity images obtained with the proposed method were all higher than those obtained with a 2-D tracking method. Furthermore, in three orthogonal views of accumulated axial strain images, the breast lesion was clearly visible with good correspondence between the axial strain and B-mode images.     

Evaluation of solid breast lesions with power Doppler sonography.

PURPOSE: We compared the abilities of power and conventional color Doppler sonography to depict the vascularity of solid breast lesions and evaluated the usefulness of power Doppler sonography in differentiating between benign and malignant breast lesions. METHODS: One hundred two solid breast lesions (59 benign and 43 malignant lesions) were studied with power and color Doppler sonography. Power and color Doppler sonograms were retrospectively compared for the depiction of blood flow signals. Power Doppler images were also reviewed for the amount of Doppler signals, pattern of vascularity, and morphology of vessels. The sensitivity, specificity, and accuracy of the 2 techniques were calculated. RESULTS: Compared with color Doppler sonography, power Doppler sonography depicted flow superiorly in 61 cases (60%) and equally in 41 cases (40%). On power Doppler sonography, the incidence of marked blood flow in malignant lesions (65%) was higher than that in benign lesions (39%). The pattern of vascularity was predominantly central (86%) and/or penetrating (65%) more often in malignant lesions than in benign lesions (51% and 34%, respectively). Branching (56%) and disordered vessels (42%) were seen more often in malignant lesions than in benign lesions (22% and 8%, respectively). The sensitivity, specificity, and accuracy in diagnosing malignancy were 64%, 76%, and 71%, respectively, for power Doppler sonography and 77%, 76%, and 76% for color Doppler sonography. CONCLUSIONS: Power Doppler sonography was more sensitive than color Doppler sonography in the detection of flow in solid breast lesions. Although power Doppler sonography was not more effective in diagnosing malignant lesions, central and penetrating vascularity patterns and branching and disordered vessels seem to be helpful findings in predicting malignancy.