乳腺MR T2*W首次通过灌注成像方法及价值探讨

目的 评价同一次乳腺MRI检查中,T1W动态增强成像之前行T2*W首次通过灌注成像的可行性及价值.方法 27例乳腺疾病患者在磁共振常规扫描之后依次行T2*W首次通过灌注成像及T1W动态增强扫描.对T2*W首次通过灌注图像及T1W动态增强图像进行后处理,得出灌注时间-信号强度曲线及T1W动态增强时间-信号强度曲线,计算病灶T2*W首次通过灌注成像的最大信号丢失率.结果 良恶性病灶之间的最大信号丢失率差异具有显著的统计学意义(P＜0.01);良恶性病灶最大信号丢失率95% 可信区间之间无重叠.良恶性病灶在T1W动态增强曲线的平台型中有较大交叉. 结论 同一次乳腺MRI检查中T1W动态增强成像之前行T2*W首次通过灌注成像是可行的,二者结合在良恶性疾病的诊断和鉴别诊断方面具有很大意义.     

乳腺MR灌注时间-信号强度曲线表现及价值研究

目的探讨乳腺MRT2*WI首次通过灌注时间-信号强度曲线(TIC)表现及其在乳腺病变鉴别诊断中的价值。资料与方法对40例乳腺肿瘤患者行乳腺动态增强成像扫描,绘制T2*WI首次通过灌注TIC及T1WI动态增强TIC。采用Fisher’s确切概率法检验,判定良、恶性病灶T1WI动态增强及灌注TIC的差异。结果良、恶性病灶灌注TIC之间差异具有显著性统计学意义(P<0.05=0.000);良、恶性病灶T1WI动态增强TIC之间差异有显著性统计学意义(P<0.05=0.011),但在平台型曲线类型中良恶性病灶有较大重叠。结论乳腺MR灌注TIC在良、恶性病灶具有显著差别,恶性病灶灌注TIC主要表现为信号快速下降后缓慢回升(A型)与快速下降后不回升(B型);良性病灶灌注TIC主要表现为平直型(C型)及缓慢上升后平台型(D型)。灌注TIC与病灶形态学结合可大大提高乳腺疾病诊断的准确性。     

乳腺MR T1 WI动态增强与T2* WI首过灌注成像相结合对乳腺良恶性病变的鉴别价值

目的评价在单次乳腺MRI中,结合T1WI动态增强成像(dynamic contrast-enhanced T1-weighted imaging,DCE-T1WI)与T2*W首过灌注成像(T2*-weighted first-pass perfusion imaging,PWI-T2*WI)对乳腺良、恶性病变鉴别诊断的诊断价值。资料与方法 40例患者在一次乳腺MRI中,先进行DCE-T1WI,随后进行PWI-T2*WI。结果DCE-T1WI如果将流出型时间-信号强度曲线作为诊断病灶恶性的阈值,诊断敏感性为74.2%,特异性为88.9%。良、恶性病灶早期强化率差异有统计学意义(P<0.001)。如果将病灶早期强化率90%作为诊断恶性病灶的阈值,敏感性与特异性分别为83.9%、77.8%;PWI-T2*WI将病灶早期信号丢失率20%作为诊断恶性的阈值,敏感性、特异性分别为90.3%、92.9%。良、恶性病灶在PWI-T2*WI早期信号丢失率的重叠范围小于DCE-T1WI早期强化率的重叠范围。就乳腺良、恶性病灶的鉴别诊断价值而言,PWI-T2*WI中病灶早期信号丢失率高于DCE-T1WI病灶早期强化率(A值分别为0.910 vs 0.791,P=0.000)。结论 PWI-T2*WI在鉴别乳腺病灶的良、恶性方面有很高的特异性,在单次乳腺MRI中联合DCE-T1WI与PWI-T2*WI,能够提高乳腺癌诊断的准确性。     

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

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。     

Value of Dynamic Contrast-Enhanced T1-weighted MR Imaging Combined With T2*-Weighted First-Pass Perfusion Imaging in Differential Diagnosis of Breast Tumors

目的 评价在单次乳腺MRI中,结合T1WI动态增强成像(dynamic contrast-enhanced T1-weighted imaging,DCE-T1WI)与T2*W首过灌注成像(T2*-weighted first-pass perfusion imaging,PWI-T2* WI)对乳腺良、恶性病变鉴别诊断的诊断价值.资料与方法 40例患者在一次乳腺MRI中,先进行DCE-T1WI,随后进行PWI-T2* WI.结果 DCE-T1WI如果将流出型时间-信号强度曲线作为诊断病灶恶性的阈值,诊断敏感性为74.2％,特异性为88.9％.良、恶性病灶早期强化率差异有统计学意义(P ＜0.001).如果将病灶早期强化率90％作为诊断恶性病灶的阈值,敏感性与特异性分别为83.9％、77.8％;PWI-T2* WI将病灶早期信号丢失率20％作为诊断恶性的阈值,敏感性、特异性分别为90.3％、92.9％.良、恶性病灶在PWI-T2* WI早期信号丢失率的重叠范围小于DCE-T1WI早期强化率的重叠范围.就乳腺良、恶性病灶的鉴别诊断价值而言,PWI-T2* WI中病灶早期信号丢失率高于DCE-T1WI病灶早期强化率(A值分别为0.910 vs 0.791,P＝0.000).结论 PWI-T2* WI在鉴别乳腺病灶的良、恶性方面有很高的特异性,在单次乳腺MRI中联合DCE-T1WI与PWI-T2*WI,能够提高乳腺癌诊断的准确性.     

乳腺癌MR灌注成像与肿瘤微血管密度的相关性研究

目的 探讨乳腺浸润性导管癌磁共振T2*W首次通过灌注成像与肿瘤血管生成间的相关关系.方法 对26例乳腺浸润性导管癌患者行术前磁共振T2*W首次通过灌注成像,并对其手术标本进行免疫组织化学染色,计算其微血管密度,分析乳腺癌灌注成像参数与肿瘤微血管密度间的相关关系.结果 26例浸润性导管癌T2*W首次通过灌注成像最大信号强度丢失率及T2*弛豫率(△R2*Peak)与肿瘤微血管密度间存在正相关关系(r= 0.695,P=0.003;r=0.689,P=0.003).结论 T2*W首次通过灌注成像相关参数与肿瘤微血管密度正相关,可在一定程度上反映肿瘤血管生成情况.     

乳腺肿块动态增强及高分辨MRI表现与病理相关性研究

目的:探讨动态增强和高分辨MRI中乳腺良、恶性病灶的形态学及血液动力学特点,并与病理结果对照,研究其相关性。方法:31例女性患者,年龄21~66岁,平均44.6岁。所有病例均行动态增强和高分辨MRI扫描,用高压注射器,注射速率2.5ml/s。评价病灶增强图像形态学特点,并进行血流动力学分析。结果:31例患者MRI共发现51个病灶。其中恶性12例20个病灶,良性19例31个病灶。以形态不规则、毛刺征、环形强化作为诊断乳腺癌标准,敏感性分别为60%、70%、80%,特异性83.9%、100%、93.5%,准确率74.5%、88.2%、88.2%。纤维腺瘤或纤维腺瘤样增生特征性表现有分叶状、压脂T2WI及增强后低信号分隔,敏感性分别为68%、60%、72%,特异性分别为92.3%、92%、96.2%,准确率80.4%、76.5%、84.3%。早期增强率和时间信号百分比曲线类型分布在良恶性病灶之间的差异有显著性意义(P<0.05)。以Ⅱ型、Ⅲ型曲线作为诊断乳腺癌的标准,敏感性90%,特异性86.6%,诊断准确率88%。结论:乳腺癌的特征性表现有形态不规则、环形强化和毛刺征。纤维腺瘤特征性表现有分叶状、T2WI及强化后可见低信号间隔。动态增强扫描中乳腺病变的时间-信号强度百分比曲线对鉴别良、恶性病变有较大意义,但是部分良、恶性病灶的曲线有重叠表现。     

乳腺疾病的动态增强MRI与微血管密度相关性研究

目的　研究乳腺良恶性病变的动态增强MRI特征 ,并探讨动态强化特征与微血管密度 (MVD)的相关性。资料与方法　对 5 7例乳腺疾病患者行动态增强MRI。所有病例均经病理证实并行免疫组织化学染色及微血管计数。比较良恶性病变的最大强化率、信号强度达峰值时间、最大相对强化速率、信号强度 时间曲线 (SI Time曲线 )类型及MVD ,并进一步分析动态强化参数及SI Time曲线类型与MVD的关系。结果　 5 7例共计 6 1个病灶 ,恶性33个 ,良性 2 8个。良恶性病变的动态强化参数、SI Time曲线类型及MVD均有显著差异 (P <0 .0 5 )。恶性病变多呈早期快速显著强化 ,良性病变多呈延迟缓慢强化或不强化。恶性病变微血管丰富 ,良性病变微血管稀少。动态强化参数及SI Time曲线类型与MVD及其分级显著相关 (P <0 .0 5 ) ;“周边强化征”与病灶周边微血管丰富、中央微血管稀少有关。结论　乳腺良恶性病变的动态增强MRI特征与MVD及其分布密切相关 ,可用来估计乳腺肿瘤的血管生成情况     

乳腺病变的MRI诊断及鉴别诊断价值

目的 评价MRI扫描对乳腺病变的检出及良恶性病变鉴别诊断能力.方法 收集2007-02-2009-02间43例50枚(恶性＝21,良性＝29)乳腺病变患者,术前行MRI平扫及动态增强检查,检查序列T1WI、T2WI 、STIR(SPAIR)及3DTHRIVE动态增强.根据病灶形态及时间-信号强度曲线进行良恶性病变鉴别,并将影像检查结果与手术病理检查对照.结果 综合应用各MRI序列病变检出率分别98.00%;对恶性病变敏感性、特异性及准确性分别为80.95%、89.66%、86.00% .结论 MRI增强扫描及时间-信号强度曲线联合应用可提高乳腺病变诊断及鉴别诊断能力.     

乳腺肿瘤磁共振动态增强模式及与肿瘤微血管密度的相关性研究

目的:研究乳腺肿瘤动态增强MRI的强化模式及与肿瘤微血管密度的相关性.材料和方法:58例乳腺肿瘤患者,共66个病灶(恶性49个、良性17个).行动态增强MRI扫描,评价最大强化斜率(Slopemax)、峰值强化率(Emax)、峰值时间(Tmax)、增强后1～5min的强化率等指标及时间-信号强度曲线类型在良、恶性肿瘤间的差别.除2例皮纤维肉瘤,病理标本均行CD34免疫组化染色,微血管计数,采用相关分析评价其与上述强化指标及强化曲线类型的相关性.结果:乳腺良、恶性肿瘤组间的Slopemax、Emax、Tmax、E(1-3),时间-信号强度曲线类型差别有统计学意义(P＜0.05).两组间肿瘤微血管密度的差别也有明显的统计学意义(P＜0.0001),Slopemax、Emax、Tmax、E(1-4)及时间-信号强度类型与肿瘤微血管密度密切相关(P＜0.05).结论:乳腺良、恶性肿瘤的强化模式的差别与肿瘤微血管密度密切相关,可以根据不同的强化模式进行乳腺良、恶性肿瘤的鉴别.     

Breast lesions: evaluation with dynamic contrast-enhanced T1-weighted MR imaging and with T2*-weighted first-pass perfusion MR imaging

PURPOSE: To evaluate the diagnostic value of an imaging protocol that combines dynamic contrast-enhanced T1-weighted magnetic resonance (MR) imaging and T2*-weighted first-pass perfusion imaging in patients with breast tumors and to determine if T2*-weighted imaging can provide additional diagnostic information to that obtained with T1-weighted imaging. MATERIALS AND METHODS: One hundred thirty patients with breast tumors underwent MR imaging with dynamic contrast-enhanced T1-weighted imaging of the entire breast, which was followed immediately with single-section, T2*-weighted imaging of the tumor. RESULTS: With T2*-weighted perfusion imaging, 57 of 72 carcinomas but only four of 58 benign lesions had a signal intensity loss of 20% or more during the first pass, for a sensitivity of 79% and a specificity of 93%. With dynamic contrast-enhanced T1-weighted imaging, 64 carcinomas and 19 benign lesions showed a signal intensity increase of 90% or more in the first image obtained after the administration of contrast material, for a sensitivity of 89% and a specificity of 67%. CONCLUSION: T2*-weighted first-pass perfusion imaging can help differentiate between benign and malignant breast lesions with a high level of specificity. The combination of T1-weighted and T2*-weighted imaging is feasible in a single patient examination and may improve breast MR imaging.     

A wide variety of dynamic contrast-enhanced MR appearances of breast cancer: pathologic correlation study

PURPOSE: The aim of this study was to elucidate the characteristic magnetic resonance (MR) appearance of breast cancers, as well as, its variations and to investigate the pathology providing different patterns of dynamic-MR appearances. MATERIALS AND METHODS: Fifty-two women with cancer underwent mastectomy (52 tumors resected) and had MR imaging at our institution between April 2001 and March 2004. MR images of T1WI, T2WI, dynamic-MRI and contrast-enhanced T1WI were obtained and evaluated. Dynamic-MR images were correlated with pathological findings. RESULTS: Common MR appearance of breast cancer was a focal mass either with irregular or spiculated margins with similar signal intensity on T1WI as and similar to higher signal intensity on T2WI compared to the normal mammary gland. On static contrast-enhanced T1WI, apparent enhancement was typically observed. On dynamic MRI, tumor-rim-enhancement on an early phase image and washout enhancement pattern on dynamic images, both characteristic for breast cancer, were observed, however, the prevalence of them was relatively low, which could be explained by the variation of histopathology among breast cancer nodules. CONCLUSION: In diagnosing breast masses on MRI, as well as the common and characteristic findings of breast cancer, the variations of MR findings and their underlying histopathology should also be considered.     

3.0T磁共振在乳腺检查中的初步应用

目的:探讨3.0T磁共振利用体部相控阵线圈进行乳腺检查的临床应用价值.方法:36例乳腺疾病患者中隆乳术后26例,乳腺癌6例,乳腺良性病变4例,均行常规MR T1WI、T2WI和压脂序列T2WI,17例行动态增强扫描,13例行扩散加权成像,并与术后病理结果进行对照分析.结果:36例乳腺疾病患者均能显示显示乳腺结构及邻近组织情况,图像清晰无变形.22例聚丙烯酰胺水凝胶注射隆乳术后患者,注入物于T1WI呈稍低信号、T2WI呈高信号,在脂肪抑制T2WI上显示最清晰,呈均匀高信号;4例角鲨烯注射液隆胸术后,注入物在T1WI和T2WI上呈小颗粒状脂肪信号影.6例乳腺癌于DWI上呈明显高信号,动态增强曲线呈早期信号快速上升,中晚期信号强度逐渐降低表现;4例发现腋窝淋巴结转移.4例乳腺良性病变,动态增强曲线呈逐渐上升改变.结论:3.0T磁共振结合体部相控阵线圈可显示隆胸材料的性质和分布,常规MRI扫描结合DWI和动态增强扫描对乳腺良恶性病变的鉴别诊断有重要临床价值.     

周围神经鞘瘤的CT和MRI分析

目的:分析周围神经鞘瘤的CT和MRI征象及病理组织学表现.方法:回顾性分析我院经手术病理证实的周围神经鞘瘤30例的CT和MRI征象及病理表现.结果:病变发生在颈部10例、胸部6例、腹部7例(含胃部4例)、四肢7例.30例周围神经鞘瘤中25例为良性,5例为恶性.20例行CT检查,其中17例良性病灶平扫密度较均匀,4例可见点状钙化灶,增强扫描病灶呈轻至中度强化,3例恶性病灶瘤体巨大,囊变、坏死多发,增强扫描强化不均匀.10例周围神经鞘瘤行MRI检查,MRI表现:T1WI病灶呈等或稍低信号,T2 WI呈高信号,增强扫描不均匀强化,10例病灶中,2例为恶性周围神经鞘瘤并伴淋巴结转移.结论:周围神经鞘瘤的CT和MR1表现具有特征性,CT和MRI能准确地显示肿瘤形态、部位、内部结构及与邻近结构的关系,对诊断有重要帮助,对手术治疗具有重要指导作用.     

乳腺肿瘤高频彩超及超声造影与微血管密度的相关性

目的 分析乳腺良恶性肿瘤高频彩超、超声造影(CEUS)与微血管密度(MVD)的相关性,探讨超声造影对乳腺肿瘤的诊断价值.资料与方法 82例原发性乳腺肿瘤患者于术前行常规高频彩超检查,观察病灶灰阶图像特征及血流特征;启动造影模式行实时灰阶谐波超声造影检查,应用时间-信号强度曲线分析软件分析病灶增强达峰时间(TTP)、峰值强度(PI)、曲线下面积(AUC);采用免疫组化测定肿瘤内MVD,分析超声造影定量参数与MVD的相关性.结果 恶性组肿瘤血流Adler分级低于良性组(P＜0.05);超声造影显像特点:恶性组血管数量多且粗细不等,良性组血流束细窄、平直;恶性组TTP低于良性组,PI及AUC高于良性组(P＜0.05),MVD显著高于良性组(P＜0.001);肿瘤MVD计数随血流Adler分级升高而升高,CDF1血流丰富程度与MVD呈正相关(r=0.456,P＜ 0.01); PI与MVD呈显著正相关(r=0.783,P＜0.01).结论 超声造影能客观评价乳腺肿瘤血供,术前应用CDFI结合超声造影在体检查肿瘤血管,可为早期诊断乳腺肿瘤提供信息.     

乳腺恶性肿瘤的MRI表现及病理对照研究

目的:分析各种乳腺恶性肿瘤的MRI表现,并探讨其病理基础.材料和方法:对87名经手术病理证实的乳腺恶性肿瘤患者行MRI平扫和动态增强检查,分析比较不同病理类型乳腺恶性肿瘤的MRI特点.结果:通过分析比较87例不同病理类型乳腺恶性肿瘤的MRI表现及其时间-信号强度曲线类型,发现浸润性导管癌多呈星芒状或蟹足状肿块,边缘不规则或伴毛刺,边界不清,内部信号不均匀,增强多呈明显不均匀强化,或不规则环状强化,SI-Time曲线以Ⅲ型为主;导管原位癌常为局限于一个象限内的锲形分布不规则异常信号灶,内部信号不均匀,边界不清,增强后呈线样分支状强化,SI-Time曲线以Ⅱ、Ⅲ型为主;黏液腺癌多表现T2WI较高信号,增强后无明显强化或仅见轻度强化改变,SI-Time曲线以Ⅳ型为主;交界性分叶状肿瘤瘤体较大,边缘呈分叶状,有多结节融合样改变,增强后多呈均匀强化,部分内部可伴囊变;转移性乳腺癌为多发性明显强化的类圆形肿块,边缘光整;湿疹样癌多表现为乳头表面凹凸不平,增强后明显强化;乳腺淋巴瘤、髓样癌及腺样囊性癌等少见病变亦因其不同的病理基础而有其特征性的影像学表现.结论:乳腺恶性肿瘤因其不同的病理基础,表现出不同的MRI特征,正确认识将有助于对乳腺病变作出准确的定性诊断.     

Quantitative gadopentetate-enhanced MRI of breast tumors: testing of different analytic methods.

This study assessed several proposed imaging strategies and analytic methods based on gadopentetate-enhanced MRI to differentiate benign from malignant breast tumors in a blinded experimental animal study. Steady-state dynamic MRI and first-pass imaging, performed with either T(1)- or T*(2)- weighted sequences, were compared. Semiquantitative and quantitative analysis methods, based on empirical measures of the data or physiological models, were subsequently applied to the imaging datasets. Comparative measures provided pathologic distinction of benign from malignant tumors, tumor grading, and histologic determination of microvascular density. Of the eight tested methods, only one, an estimate of first-pass perfusion using T *(2)-weighted imaging, showed an almost significant (P = 0.05) difference between benign and malignant tumors and correlated almost significantly (r =.3, P = 0.06) with the tumor grade. All other tests, performed either with steady-state imaging or with T(1)-weighted first-pass imaging, failed to differentiate benign from malignant tumors. In addition, they yielded poor correlations with tumor grade and microvascular density.     

超声造影对肾脏小占位的诊断分析

目的:探讨不同病理类型肾脏肿瘤的造影特点,评价超声造影诊断肾脏良恶性肿瘤的应用价值,为临床诊断提供依据。方法:应用声学造影剂声诺维对27例超声诊断为肾脏占位病变或可疑肾脏占位病变的患者进行超声造影检查,分析其造影增强图像特点。结果:27例患者均满意获得清晰的肿瘤动态造影灌注图像,大部分与其正常肾组织回声等强,10例肾恶性肿瘤的造影显像比其正常肾组织快,3例肾良性肿瘤造影显像为"同进慢出";4例肾柱肥大造影后与正常肾组织造影剂显像一致;2例肾囊肿内无造影剂显示。结论:超声造影成像技术能清晰显示肾肿瘤的血流灌注特点,对肾脏肿瘤的诊断具有一定实用价值。