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1.
Our aim was to evaluate quantitative parametric analysis for characterization of breast lesions in contrast-enhanced magnetic resonance (MR) mammography. In 62 patients, contrast-enhanced MR mammography revealed 75 suspicious lesions, of which 18 were benign and 57 were malignant. The quantitative parametric analysis delineates signal intensity changes of contrast-enhanced lesions on a pixel-by-pixel basis. The initial rate of enhancement is coded by color intensity: a slow rate is coded to dark; a fast rate, bright. The postinitial enhancement change is coded by color hue: blue for increasing signal intensity, green for plateau, and red for decrease in signal intensity. Malignant lesions showed a significantly higher number of bright-red (P=0.004) and medium-red (P<0.001) pixels than benign lesions. Benign lesions showed significantly more blue pixels than did malignant lesions (P=0.010). Of the 75 lesions, 72 (96%) showed heterogeneous distribution of pixel color hue. Quantitative parametric analysis of contrast kinetics in lesions can replace the subjective manual region of interest (ROI) method and makes a step toward standardization of MR mammography. It allows quantitative evaluation of different contrast kinetics parameters in contrast-enhanced breast lesions.  相似文献   

2.
PURPOSE: To compare the diagnostic performance of breast lesions by the enhancement patterns and morphologic criteria on magnetic resonance imaging (MRI). MATERIALS AND METHODS: Both T1-weighted 3D gradient-echo sequences with high temporal resolution and high-spatial-resolution MRI were performed on 190 patients with a total of 204 enhancing lesions (144 malignant and 60 benign). The enhancement patterns and morphologic features of each mass and nonmass lesion were analyzed, and the diagnostic performance was compared. RESULTS: The sensitivity and specificity of the morphologic criteria were statistically significantly higher than those of the enhancement patterns (sensitivity: P = 0.0012, specificity: P = 0.0003), and the A(z) values for the three observers were 0.900, 0.919, and 0.900. The diagnostic accuracy of the morphologic criteria for both types of lesions was superior, and the differences were statistically significant (mass: P = 0.0001, nonmass: P = 0.0389). CONCLUSION: The analysis of the morphologic features of enhancing breast lesions alone showed higher diagnostic performance; therefore, signal intensity (SI) time-course data may not be needed to diagnose malignant breast lesions.  相似文献   

3.
OBJECTIVE: The aim of our study was to differentiate benign from malignant breast lesions that had been detected exclusively on MR imaging by analyzing qualitative and quantitative lesion characteristics. MATERIALS AND METHODS: We performed 51 MR imaging-guided breast interventions (41 preoperative lesion localizations and 10 large-core needle biopsies) in 45 patients with exclusively MR imaging-detected lesions. All patients had previously undergone diagnostic dynamic contrast-enhanced MR imaging of the breast with a double breast coil at 1.0 T (n = 36) or 1.5 T (n = 15). The diagnostic MR images were evaluated on a workstation. Lesion morphology (size, shape, margin type, enhancement pattern), signal intensity parameters (time to peak enhancement, maximum slope of enhancement curve, washout, relative water content), and scores analogous to the Breast Imaging Reporting and Data System (BI-RADS) categories were correlated with histology. RESULTS: Histology revealed malignancy in 37.3% (19/51) of the lesions. The positive predictive value for malignancy of exclusively MR imaging-detectable lesions increased as the analogous BI-RADS category increased. Late inhomogeneous contrast enhancement was the only morphologic criterion that was statistically significantly correlated with malignancy. Malignant and benign lesions did not differ significantly in any of the quantitatively evaluated signal intensity parameters. Carcinomas showed a tendency toward faster and stronger enhancement and stronger washout. CONCLUSION: The classification of exclusively MR imaging-detectable breast lesions according to a combination of morphologic and perfusion parameters including the late enhancement pattern helps identify the lesions for which interventional MR imaging is required. Quantitative signal intensity data alone do not suffice.  相似文献   

4.
乳腺MRI动态增强对良恶性病变的鉴别价值   总被引:2,自引:0,他引:2       下载免费PDF全文
杜铁桥  丁宝芝  桑春玉  张超   《放射学实践》2009,24(2):170-174
目的:探讨磁共振动态增强技术(DCE-MRI)对乳腺良恶性病变的鉴别诊断价值。方法:18例乳腺良性病变、16例恶性肿瘤及2例交界性病变患者行DCEMRI检查(平均年龄51.7岁)。对病变的边缘、形态、有无播散征、时间信号曲线、最大增强斜率(MSI)、信号增强率(SER)和信号增强幅度(SEE)等7项指标进行了良恶性组比较。结果:除了MSI以外,其余6项指标在良恶性组之间差异均有显著性意义。用病变形态、时间信号曲线及SEE等五项指标对36例乳腺病变综合评分结果显示:综合评分对诊断乳腺恶性肿瘤的灵敏度、特异度和准确性分别为93.8%、83.3%及88.2%。结论:结合DCE~MRI的病变形态学改变及动态增强表现对乳腺良恶性病变的鉴别有很好的诊断价值。  相似文献   

5.
目的评价健康人停经前乳腺动态增强MRI表现,探讨其鉴别健康人停经前乳腺实质内出现的增强灶和良恶性病变的能力.材料和方法对18例健康自愿者和40例乳腺病变患者行3D动态增强MRI检查.分析实质增强灶数量、形态、早期增强率和时间-信号强度曲线形态并与良恶性病变比较.结果55.6%的自愿者乳腺内出现实质增强灶.其表现为片状或结节状,边缘模糊、不规则或光滑,早期增强率小于良恶性病变,与腺体无明显差异,时间-信号强度曲线均为单相型,明显不同于恶性病变.结论停经前妇女乳腺内出现对比增强灶是一种正常表现,时间-信号强度曲线是鉴别实质增强灶与恶性病变的很好方法.  相似文献   

6.
Increases in signal intensity enhancement were measured in defined regions of interest (ROIs) to allow distinction between malignant and benign tumors with dynamic gadolinium-enhanced magnetic resonance (MR) mammography. Twenty patients with palpable breast lesions (15 malignant, five benign) underwent MR mammography. The dynamic gradient-echo sequence was performed with intravenous bolus injection of gadopentetate dimeglumine and consisted of 25 images with a time resolution of 30 seconds. Contrast enhancement was calculated by comparing user-defined ROIs on pre- and postcontrast images. An increase in signal intensity of 70% or more on the 1-minute postcontrast image was used as the criterion of malignancy. MR mammographic results correlated with histopathologic findings in all patients when the defined ROI was in the most enhancing part of the tumor. For the ROI in areas of submaximal enhancement or when the ROI surrounded the whole lesion, only five and nine tumors, respectively, fulfilled the malignancy criterion. All malignant tumors showed large variations in signal intensity enhancement that depended on the position of the ROI in the tumor. Dynamic, gadolinium-enhanced MR mammography allows distinction of benign from malignant breast tumors when the selected ROI is in the most enhancing part of the lesion.  相似文献   

7.
乳腺磁共振成像:组织学与病灶定性、定量特征的相关性   总被引:3,自引:0,他引:3  
目的 通过分析定性、定量MR特征鉴别良、恶性乳腺病灶。方法 对 46例患者的病灶定性、定量MR特征及BI -RADS分类积分与组织学的相关性进行比较。结果 定性特征中的形状、边缘类型、T2 WI相对信号强度、早期周边环形强化、晚期不均匀强化、时间 -信号强度曲线类型与恶性具有统计学显著相关性 (Ρ <0 .0 5 ) ;定量特征中的强化峰值时间、增强曲线最大斜率和流出率与恶性具有统计学显著相关性 (Ρ <0 .0 0 1) ;BI -RADS分类积分系统与恶性具有统计学显著相关性 (Ρ <0 .0 0 1)。结论 定性、定量特征相结合能够提高乳腺病灶诊断的准确性。  相似文献   

8.
Forty-nine pathologically proven gallbladder lesions were evaluated in 45 patients using dynamic MRI with a spoiled gradient pulse sequence (SPGR), to access the ability of this technique to differentiate benign from malignant gallbladder lesions. The studies were reviewed retrospectively. Signal intensity of the lesions were measured. Twenty-one malignant and 28 benign lesions were classified into three categories: polypoid, diffuse wall thickening, and exophytic. Early and delayed enhancement patterns were evaluated. For the polypoid masses, malignant lesions (n = 9) demonstrated early and prolonged enhancements, whereas benign lesions (n = 14) had early enhancement with subsequent washout (P < .05). For diffuse gallbladder wall thickening, malignant lesions (n = 6) demonstrated early and prolonged enhancement and benign lesions (n = 14) showed relatively slow, prolonged enhancement (P < .05). The exophytic masses (n = 6) all were malignant and demonstrated early and prolonged enhancement. Dynamic MRI can help differentiate benign from malignant gallbladder lesions.  相似文献   

9.
PURPOSE: To assess the relevance of the signal intensity time course for the differential diagnosis of enhancing lesions in dynamic magnetic resonance (MR) imaging of the breast. MATERIALS AND METHODS: Two hundred sixty-six breast lesions were examined with a two-dimensional dynamic MR imaging series and subtraction postprocessing. Time-signal intensity curves of the lesions were obtained and classified according to their shapes as type I, which was steady enhancement; type II, plateau of signal intensity; or type III, washout of signal intensity. Enhancement rates and curve types of benign and malignant lesions were compared. RESULTS: There were 101 malignant and 165 benign lesions. The distribution of curve types for breast cancers was type I, 8.9%; type II, 33.6%; and type III, 57.4%. The distribution of curve types for benign lesions was type I, 83.0%; type II, 11.5%; and type III, 5.5%. The distributions proved significantly different (chi 2 = 139.6; P < .001). The diagnostic indices for signal intensity time course were sensitivity, 91%; specificity, 83%; and diagnostic accuracy, 86%. The diagnostic indices for the enhancement rate were sensitivity, 91%; specificity, 37%; and diagnostic accuracy, 58%. CONCLUSION: The shape of the time-signal intensity curve is an important criterion in differentiating benign and malignant enhancing lesions in dynamic breast MR imaging. A type III time course is a strong indicator of malignancy and is independent of other criteria.  相似文献   

10.
To assess the effectiveness of gadopentetate dimeglumine in the magnetic resonance (MR) imaging evaluation of soft-tissue masses without osseous involvement, 30 patients underwent MR imaging before and after administration of contrast material (0.1 mmol/ kg) of the 30 lesions, 22 were benign and eight were malignant; histologic confirmation was available in all lesions except one benign lesion. Overall, enhancement was detected in 26 (87%) of 30 lesions: 18 (82%) of the 22 benign lesions and eight (100%) of eight malignant lesions. Enhancement was characterized as homogeneous (two [11%] benign lesions, two [25%] malignant lesions), inhomogeneous (11 [61%] benign lesions, six [75%] malignant lesions), or peripheral (five [28%] benign lesions, no malignant lesions) of the 19 lesions assessed for a change in enhancement over time, seven (37%) showed an increase and two (11%) showed a decrease in signal intensity. The authors conclude that benign and malignant soft-tissue lesions could not be differentiated solely on the basis of enhancement (pattern, degree, or time course).  相似文献   

11.
目的探讨乳腺癌动态增强扫描相关参数在乳腺癌诊断中的价值。方法对93例患者行MR平扫、动态增强扫描。分析形态学、增强曲线类型及最大斜率对乳腺癌的诊断价值。结果 (1)形态学表现及病理结果:105个肿块的强化形式可分为五型:①无强化9个(囊肿);②均匀强化31个(纤维腺瘤9个,乳腺癌11个,增生10个,叶状瘤1个);③不均匀强化42个(纤维腺瘤5个,增生3个,乳腺癌33个,叶状瘤1个);④边缘强化17个(乳腺癌15个,纤维腺瘤及炎症各1个);⑤网状强化2例(乳腺炎,巨乳症各1例)。⑥导管状强化4个(增生1个,导管癌3个)。(2)曲线类型及病理结果:I型曲线20个,II型曲线42个,III曲线型43个。六种表现形式①曲线信号强度基本无增加9个(囊肿);②曲线信号强度缓慢持续增加6个(增生2个,纤维腺瘤2个,慢性炎症1个,导管内癌1个);③曲线号强度早期迅速增加后仍持续缓慢增加5个(增生4个,炎性乳腺癌1个);④曲线早期信号强度迅速增加之后基本停止而形成中晚期的平台42个(增生9个,纤维腺瘤8个,叶状瘤1个,乳腺癌24个);⑤曲线早期信号强度迅速增加到达峰值,之后信号强度逐渐下降40个(增生1个,纤维腺瘤5个,叶状瘤1个,乳腺癌33个);⑥曲线早期信号强度迅速增加到达峰值,呈平台期后又迅速上升3个(均为乳腺癌)。(3)增强斜率及病理结果:62个恶性病灶的平均最大斜率为19.19±8.13,43个良性病灶平均最大斜率为9.46±6.64,二者差异有非常显著性意义(P<0.01)。以14.85为临界值,敏感性为67%,特异性为83%;以17.10为临界值,特异性为100%。结论增强形态学特征、最大斜率在良、恶性病变,尤其是II型曲线的鉴别诊断中具有重要价值。  相似文献   

12.
PURPOSE: 2- and 3-dimensional evaluation of quantitative pharmacokinetic parameters derived from the Tofts model modeling dynamic contrast enhancement of lesions in MR mammography. MATERIALS AND METHODS: In 95 patients, MR mammography revealed 127 suspicious lesions. The initial rate of enhancement was coded by color intensity, the post-initial enhancement change is coded by color hue. 2D and 3D analysis of distribution of color hue and intensity, vascular permeability and extracellular volume were performed. RESULTS: In 2D, malignant lesions showed significant higher number of bright red, medium red, dark red, bright green, medium green, dark green and bright blue pixels than benign lesions. In 3D, statistical significant differences between malignant and benign lesions was found for all this parameters. Vascular permeability was significant higher in malignant lesions than in benign lesions. Regression model using the 3D data found that the best discriminator between malignant and benign lesions was combined number of voxels and medium green pixels, with a sensitivity of 79.4% and a specificity of 83.1%. CONCLUSIONS: Quantitative analysis of pharmacokinetic variables of contrast kinetics showed significant differences between malignant and benign lesions. 3D analysis showed superior diagnostic differentiation between malignant and benign lesions than 2D analysis. The parametric analysis using a pharmacokinetic model allows objective analysis of contrast enhancement in breast lesions.  相似文献   

13.
增强MRI诊断乳腺良恶性病变的价值   总被引:32,自引:3,他引:32  
目的评价增强MRI对乳腺良、恶性病变的诊断价值。方法对48例乳腺病变患者进行MRI平扫和增强扫描,并对照X线、B超及手术病理结果,分析比较了病变强化后形状、边界、内部信号、强化速度与程度以及强化消失快慢等特征。结果48例乳腺病变患者81个病灶的良、恶性诊断准确率为92.6%。结论增强MRI是鉴别乳腺良、恶性病变的一种有效的影像学诊断方法  相似文献   

14.
目的评价MR T2W I和增强检查对胸膜局灶性病变的诊断价值。方法本组31例胸膜局灶性病变均经手术或穿刺活检细胞病检或临床追踪证实。其中恶性肿瘤16例,良性病变15例。MR动态增强扫描后在工作站上比较信号强度和增强形态,并将感兴趣区(RO I)的信号强度绘制成时间-信号强度曲线(TIC),分别计算其0.5 m in斜率值。结果31例胸膜局灶性病变在T2W I平扫的表现上良恶性比较差异有统计学意义(P均<0.05)。本组TIC可分为3型,Ⅰ型17例(恶性肿瘤14例,良性病变3例);Ⅱ型4例(恶性肿瘤2例,良性病变2例);Ⅲ型10例(均为良性病变)。16例恶性肿瘤中14例病变的0.5 m in斜率值>0.00227;15例良性病变中8例病变的0.5 m in斜率值<0.00227;良恶性病变的TIC斜率值之间存在显著性差异。以0.5 m in斜率值0.00227作为鉴别胸膜局灶性良恶性的阈值,31例病变中22例诊断准确,敏感度为87.5%,特异度为53.3%。结论以病灶信号特点、形态、曲线类型或斜率值等判别胸膜病灶的良恶性,有一定的参考价值。  相似文献   

15.
The purpose of this study was to evaluate the utility of a dynamic contrast enhanced FLASH-2D sequence for differential diagnosis of tumours in head and neck in 93 patients. Initially, the localization of the lesion and the selection of four representative slices for the dynamic study were obtained by a T2-weighted spin-echo sequence (TR 2000–3000 ms; TE 25/90 ms). After IV bolus injection of the contrast agent 10 images were acquired during a period of 3 min by a FLASH-2D sequence (TR 60 ms; TE 6 ms; flip angle 40° matrix 256 × 256; one acquisition). The percentage signal intensity (SI) increase (r) and the slope (S) of the curve were calculated on the basis of the SI time curve of the pathological lesion and of muscle. Inflammatory processes could be differentiated from malignant or benign tumours by means of a higher contrast enhancement. The time of the maximum SI was not specific for the different lesions. In comparison with muscle the maximum SI change was achieved earlier in a pathological process. Correspondence to: J. Mäurer  相似文献   

16.
PURPOSE: To investigate the feasibility of combined dynamic contrast enhanced (DCE) and magnetic resonance spectroscopy (MRS) in evaluating breast lesions. METHODS: Nine patients with positive mammograms scheduled for either biopsy or mastectomy were examined on a 1.5-T MR scanner. DCE was performed with administration of gadolinium-DTPA contrast using a two-dimensional spoiled gradient recall echo (SPGR) sequence. Proton spectroscopy (TR/TE = 2000/272 msec) was performed using PRESS single slice (10 mm). Lesion time intensity curves were classified as persistent (type 1), plateau (type 2), or washout (type 3) pattern enhancement. Choline (Cho) signal-to-noise ratios (SNRs) and enhancement patterns were compared between benign and malignant lesions as determined by histopathology. RESULTS: Five patients had breast carcinoma and four had benign lesions. Type 1 enhancement was found in two benign cases, type 2 enhancement in two of four benign and four of five malignant lesions, and one malignant case exhibited a type 3 pattern. Choline SNR was significantly different (P < 0.003) between benign and malignant lesions (2.0 +/- 0.3 vs. 5.7 +/- 1.4; P < 0.003). Choline SNR was less than 4.0 in all of the benign lesions, including the two lesions with type 2 enhancement. CONCLUSION: Proton MRS appears to be a promising technique for classification of breast lesions when DCE results are equivocal. A combination of DCE and MRS is feasible, and may have improved specificity compared to either modality alone.  相似文献   

17.
OBJECTIVES: We sought to investigate the potential value of magnetic resonance (MR) elastography to improve the differentiation between benign and malignant tumors. MATERIAL AND METHODS: Measurements of 5 patients with 6 malignant lesions, 11 patients with benign lesions, and 4 patients with no lesions at all were performed at 1.5 Tesla. After breast MR imaging, MR elastography was performed as a targeted measurement. Low-frequency mechanical waves (65 Hz) were transmitted into the breast tissue using an oscillator and were displayed by means of a MR sequence within the phase of the MR image. After reconstruction, the viscoelastic information was correlated with the signal intensity and morphology data. RESULTS: All examinations were technically successful realized in approximately 25 minutes. Malignant tumors documented higher values of elasticity than benign corresponding with signal intensity and morphologic data. CONCLUSION: A good separation exists between benign and malignant lesions in elasticity, corresponding with specific signal intensity and morphologic data. Further clinical studies with a larger number of patients are needed for extended validation.  相似文献   

18.
MR重T2W首次通过灌注成像鉴别乳腺良恶性肿瘤的价值初探   总被引:12,自引:1,他引:11  
目的 评价在同 1次检查中T1W动态增强成像之后进行重T2 W (T 2 W )首次通过灌注成像的可行性 ,以及后者在鉴别乳腺良恶性肿瘤方面的诊断价值。方法  2 9例乳腺病患者在T1W动态增强后进一步行病灶局部的T 2 W首次通过灌注成像 ,分别根据病灶T1W动态增强的早期强化程度和T 2 W首次通过灌注成像的早期信号丢失程度判定病灶的良恶性 ,计算其敏感度、特异度 ,以进行两方法间的比较。结果 应用T1W动态增强成像序列 ,良、恶性病变的信号强度增加率之间差异有显著性意义 (t=2 5 6 3,P =0 0 16 ) ,但两者的早期增强程度范围有很大的重叠 ;早期增强率诊断的敏感度为 94 % ,特异度仅为 2 5 %。应用T 2 W首次通过灌注成像序列 ,良、恶性病变之间的T2 信号强度丢失程度差异有非常显著性意义 (t=4 777,P <0 0 0 1) ,良、恶性病变的早期信号丢失率之间重叠很少 ;早期信号丢失率诊断的敏感度为 88% ,特异度为 75 %。结论 T 2 W首次通过灌注成像在鉴别良恶性乳腺肿瘤方面具有较高特异度 ;在同一患者中 ,T 2 W首次通过灌注成像结合T1W动态增强成像检查是可行的 ,可以提高乳腺MR成像的诊断准确性。  相似文献   

19.
PURPOSE: To investigate the usefulness of early and delayed hepatic MRI after mangafodipir trisodium (Mn-DPDP) administration for the detection and characterization of focal hepatic lesions. MATERIALS AND METHODS: Forty-five patients (31 males and 14 females, mean age = 61 years) with a total of 113 hepatic lesions (mean size = 3.5 cm) were included in this study (15 with hepatocellular carcinoma (HCC, N = 35), 20 with hepatic metastasis (N = 63), five with hemangioma (N = 10), three with cholangiocarcinoma (CC, N = 3), and two with liver abscess (N = 2)). T1-weighted gradient-echo MR images were obtained before and after Mn-DPDP administration, with a mean 18-hour delayed imaging. A qualitative analysis (including the size and signal intensity (SI)) and quantitative analysis (including enhancement and lesion-liver contrast-to-noise ratio (CNR)) were performed on pre- and postcontrast early and delayed MR images. RESULTS: Compared to postcontrast early imaging, 17 (48.6%) of 35 HCCs showed higher SI, 16 (45.7%) showed no SI change, and two (5.7%) showed lower SI on delayed imaging. All 63 metastases, 10 hemangiomas, three CCs, and two abscesses showed no SI change. On delayed imaging, ring enhancement was noted in 53 metastases (84.1%), three hemangiomas (30.0%), and one abscess (50.0%), but was not seen in HCCs or CCs. Eight metastases (12.7%) also showed ring enhancement on postcontrast early imaging. No newly detected hepatic lesions were revealed on postcontrast delayed MR images compared to postcontrast early images. Regarding CNR, the HCCs showed a significant increase in CNR from postcontrast early to delayed images after administration of Mn-DPDP (P < 0.01). However, none of the metastases, hemangiomas, CCs, and abscesses showed a significant increase of CNR from postcontrast early to delayed images. CONCLUSION: Postcontrast delayed MR images after Mn-DPDP administration were helpful in distinguishing hepatocellular from nonhepatocellular lesions, but were not useful for lesion detection and had limited utility for lesion characterization, since benign and malignant hepatic lesions looked the same.  相似文献   

20.
The histopathological variations of segmental enhancement on breast magnetic resonance imaging (MRI) were investigated, with the aim of identifying imaging characteristic clues to their differential diagnosis. We reviewed 70 breast MRI examinations demonstrating segmental enhancement, classified them based on their histopathology, and assessed their MRI findings as follows: (1) confluent or not confluent, (2) late enhancement pattern, and the absence or presence of (3) clustered ring enhancements and (4) surrounding high signal intensity (SI) on T2-weighted imaging. Thirteen lesions (18.5%) were benign, eight (11.5%) were high risk, 25 (36%) were ductal carcinoma in situ (DCIS) and 24 (34%) were infiltrating mammary carcinomas (IMC). Clustered ring enhancements were demonstrated in 74% of malignancies (high risk, DCIS and IMC) but no benign lesions (P = 0.0001). The surrounding high SI on T2-weighted imaging was seen in four of five IMC with marked lymphatic involvement. Clustered ring enhancement was not demonstrated in six of seven IMC of tubular and/or lobular types. Segmental enhancement was seen in not only DCIS but also IMC, high-risk and benign lesions. Clustered ring enhancement and surrounding high SI on T2-weighted imaging were clues to their differential diagnosis and helpful to decide their diagnostic strategy.  相似文献   

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