MR扩散加权成像对乳腺良恶性疾病的应用研究

目的探讨MR扩散加权成像（DWI）的技术方法及表观扩散系数（ADC）值对乳腺良、恶性疾病的诊断及鉴别诊断价值。资料与方法经病理证实的乳腺病变50例,58个病灶,其中恶性32个,良性26个。检查使用Siemens1.5T磁共振仪、专用双穴乳腺表面线圈。所有病例采用单次激发自旋回波-回波平面成像（SE-EPI）序列行DWI,扩散敏感系数（b值）取0、400、600、800、1000s/mm^2。以恶性病变ADC值95%可信区间的上界作为诊断病变良、恶性的界值,所得结果与病理结果比较。结果DWI显示92.3%（24/26）的良性病变和96.9%（31/32）的恶性病变,敏感性为94.8%（55/58）。各b值良性组、恶性组和正常组之间的ADC值差异均有统计学意义（P〈0.05）。取b=1000s/mm^2,以恶性病变ADC值95%可信区间的上界1.4276×10^-3mm/s为界诊断良、恶性的敏感性为90.6%,特异性为84.6%,准确性为87.9%。结论（1）DWI对乳腺疾病的敏感性非常高。（2）ADC值是诊断和鉴别诊断乳腺良、恶性疾病的有价值的参数。（3）b=1000s/mm^2时对乳腺疾病的诊断最有价值。     

乳腺磁共振扩散加权成像的应用

目的：探讨乳腺磁共振扩散加权成像（DWI）检查的可行性,并重点探讨影响DWI图像质量的技术参数。方法：使用GE1．5T磁共振扫描仪及阵列线圈对32例乳腺疾病患者行常规SE序列扫描,其中19例为良性肿瘤,5例炎性病变,6例恶性肿瘤．均经手术及病理证实;另硅胶置入2例。使用体线圈行DWI序列扫描,采用全方位扩散梯度及5个b值扫描。DWI总的扫描时间40s。结果：在DWI序列扫描中,良性和恶性肿瘤均为高信号,计算ADC值可鉴别良性和恶性肿瘤．通过各种扫描参数的合理匹配,可使图像质量的信噪比达到最佳,并减少图像的几何变形。结论：DWI对于检查乳腺病变是一种快速可行并行之有效的技术。     

不同扩散梯度因子值的乳腺MR扩散加权成像对比研究

目的 确定一个最佳的用于乳腺MR DWI的b值.方法 按照前瞻性设计,选取怀疑乳腺癌的乳腺可触性包块患者40例,术前行双侧乳腺MR和DWI扫描,b值分别取1000、800和600 s/mm2,肉眼判断DWI图像等级,采用单因素方差分析比较3组b值的DWI像信噪比和病灶ADC值,采用ROC曲线评价ADC值诊断价值.结果40例患者中乳腺癌26例,良性肿块14例,DWI显示36例,共42个病灶.3组b值下的DWI图像质量均较好,加例中视觉分级达A级的分别占75.0%(30例)、77.5%(31例)和77.5%(31例).3组b值DWI图像对病灶的检出能力相同.b=1000、800和600 s/mm2的信噪比平均值分别为63±22、82±27和96±29,3组间比较差异具有统计学意义(P<0.01).良性病变平均ADC值分别为(1.44±0.28)× 10-3、(1.50±0.32)×10-3和(1.52±0.29)×10-3mm2/s,3组间比较差异无统计学意义(P=0.725).恶性病变平均ADC值分别为(1.00±0.25)×10-3、(0.98±0.19)×10-3和(1.07±0.22)×10-3mm2/s,3组间比较差异也无统计学意义(P=0.358).3组b值的ADC值诊断乳腺良恶性病变的ROC曲线下面积分别为0.879、0.885和0.865;诊断良恶性病变的阈值分别为1.295×10-3、1.435×10-3和1.335×10-3mm2/s;诊断乳腺癌的敏感性分别为80.0%、92.0%和84.0%,特异性均为90.0%;阳性预测值分别为95.2%,95.8%和95.5%.结论综合图像信噪比和ADC值诊断价值,认为在乳腺DWI中,b=800 s/mm2是乳腺DWI成像的最佳b值.     

不同抑脂序列在3.0 T乳腺MR扩散加权成像中的应用比较

目的 比较4种不同脂肪抑制序列的3.0T MR正常乳腺扩散加权成像(DWI)的图像质量,从而优化和筛选3.0T乳腺MR DWI的最佳脂肪抑制技术.方法 在3.0 T MRI上,分别对44例女性乳腺受检者应用选择性水激励技术(water excitation)、频率选择脂肪饱和技术(Fatsat)、反转恢复技术(IR)、频率选择反转脉冲脂肪抑制技术(Fatsat+ IR)4种不同脂肪抑制序列行DWI,其他参数相同.比较不同抑脂序列的DWI图像质量,测量并计算不同抑脂序列DWI图像的乳腺组织信噪比(SNR),并进行统计学分析.结果 应用water excitation的DWI图像质量平均评分为3.07±0.79,主观质量评分达到3分(可以诊断)及以上者34例,占总检查例数的77.27％;应用Fatsat的DWI图像质量平均评分为2.43±0.82,主观质量评分达到3分及以上者20例,占总检查例数的45.45％;应用IR的DWI图像质量平均评分为1.32±0.60,主观质量评分达到3分及以上者3例,占总检查例数的6.82％;应用Fatsat+IR的DWI图像质量平均评分为2.07±0.99,主观质量评分达到3分及以上者15例,占总检查例数的34.09％.统计结果显示不同抑脂序列的DWI图像质量比较差异有统计学意义(P =0.0001 ＜0.01),两两比较显示应用Water excitation的DWI图像质量明显优于Fatsat、IR及Fatsat+ IR(P值分别为0.002、0.000及0.000).应用water excitation的DWI图像乳腺组织SNR平均为52.28±19.34,应用Fatsat的DWI图像乳腺组织SNR平均为39.93±15.07,应用IR的DWI图像乳腺组织SNR平均为23.00±7.34,应用Fatsat+IR的DWI图像乳腺组织SNR平均为28.55±9.36.统计结果显示不同抑脂序列DWI图像乳腺组织SNR差异有统计学意义(F=90.73,P=0.0000＜ 0.01),两两比较显示应用water excitation的DWI图像乳腺组织SNR明显优于其他3组(P值均为0.000). 结论 在3.0T乳腺MR检查中,应用water excitation抑脂序列有助于改善DWI的图像质量,提高SNR.     

并行采集MR扩散技术对乳腺良恶性病变的临床应用价值

目的 评价并行采集MR扩散加权成像(DWI)对乳腺良、恶性病变的临床应用价值. 资料与方法 采用GE 1.5T 超导MRI仪及4通道乳腺相控阵线圈,应用ASSET EPI并用2组b值(b=0,600 s/mm2及0,1000 s/mm2)对56例患者及20名健康志愿者行ASSET-DWI、SE T1WI、FSE T2WI检查,对其中的16例患者及7名健康志愿者双侧乳腺还分别进行横轴位结合ASSET技术的EPI及常规EPI,对ASSET-DWI图像质量及诊断价值进行分析. 结果 ASSET-DWI较常规DWI采集时间缩短50%,常规DWI乳腺及3个病变不同程度变形,ASSET-DWI乳腺变形减轻,病灶无明显变形.ASSET-DWI b值为600 s/mm2或1000 s/mm2时,恶性病变、良性病变及正常腺体ADC值均明显不同(P＜0.05).分别以恶性病变95%可信区间上限1.44×10-3 mm2/s (b值600 s/mm2)及1.18×10-3 mm2/s (b值1000 s/mm2)定为良、恶性病变诊断阈值,诊断灵敏度分别为80%(32/40)和77.5%(31/40),特异度均为95%(19/20). 结论 应用ASSET-DWI对乳腺检查可以缩短采集时间,减少图像畸变.b值为600 s/mm2或1000 s/mm2时,根据病变ADC值,ASSET-DWI均可以鉴别多数乳腺良、恶性病变,ADC诊断阈值应与所用b值相匹配.     

磁共振扩散加权成像在乳腺肿瘤中的临床应用

磁共振扩散加权成像（MRdiffusion-weightedimaging,DWI）依赖病理过程中水分子在不同环境中运动差异而成像,DWI成像速度快（平均时间-200s）、无创、没有电离辐射、不需要注射对比剂等优点使其成为乳腺肿瘤方面应用最广的一种功能成像,目前,DWI在应用中存在着诸多限制因素,如场强、b值、诊断的差异等。本文就DWI成像原理及目前在乳腺良恶性病变诊断中的临床应用进行综述。     

磁共振扩散加权成像在乳腺病变诊断中的应用

目的：探讨单纯磁共振扩散加权成像对诊断乳腺病变的临床应用价值。方法：对临床拟诊为乳腺肿块的37例患者行磁共振扩散加权成像检查,并获得病理证实,其中良性病灶18个,恶性病灶19个。描记扩散图像上病变的兴趣区,由软件计算获得表观扩散系数（ADC）值。对获取数据进行统计分析,采用t检验对良性和恶性病变的ADC值进行比较。结果：12例良性病变在DWI上呈等信号或高信号,但ADC值升高或下降不明显,6例良性病变DWI上呈高信号,ADC值明显下降;19例恶性肿瘤DWI上呈高信号,ADC值明显下降。良性病变组ADC值为（1.474±0.441）×10^-3mm^2/s,恶性病变组ADC值为（1.082±0.160）×10^-3mm^2/s,两者间差异有显著性意义（P=0.002）。结论：MR扩散加权成像ADC值测量在乳腺病变定性诊断中有一定的辅助诊断价值。     

扩散加权成像在乳腺肿瘤中的应用

扩散加权成像是指在分子水平研究组织中自由水质子随意运动的功能性磁共振技术,是一种评价正常及病理组织功能性改变的无创性方法.其在乳腺中的应用为乳腺肿瘤的检出及良恶性的鉴别开拓了新的前景.就扩散加权成像的技术原理、在乳腺肿瘤中的临床应用及与其他影像学检查手段比较等方面进行介绍.     

扩散加权成像在乳腺肿瘤中的应用

扩散加权成像是指在分子水平研究组织中自由水质子随意运动的功能性磁共振技术,是一种评价正常及病理组织功能性改变的无创性方法。其在乳腺中的应用为乳腺肿瘤的检出及良恶性的鉴别开拓了新的前景。就扩散加权成像的技术原理、在乳腺肿瘤中的临床应用及与其他影像学检查手段比较等方面进行介绍。     

同一个体3.0T与1.5T乳腺MR扩散加权成像的图像质量比较

目的比较3.0 T与1.5 T MR正常乳腺组织扩散加权成像(DWI)的图像质量,从而评价3.0 T乳腺MRDWI的可行性。方法对44名女性乳腺受检者分别在3.0 T MR与1.5 T MR上行DWI。3.0 T DWI应用选择性水激励(Water excitation)技术行脂肪抑制,1.5 T DWI应用频率选择脂肪饱和(Fatsat)技术行脂肪抑制,b值均为0,1000 s/mm2,其他参数相同。比较3.0 T及1.5 T乳腺MR DWI图像的主观质量评分,测量并计算3.0 T及1.5 T乳腺MR DWI乳腺组织信噪比(SNR)及表观扩散系数(ADC)值,进行统计学分析。结果 3.0 T乳腺MR DWI的图像质量平均评分为(3.07±0.79),主观质量评分达到3分(可以诊断)及以上者为34名,占总检查例数的77.27%。1.5 T乳腺MR DWI的图像质量平均评分为(3.23±0.52),主观质量评分达到3分及以上者为42例,占总检查例数的95.45%。两者比较差异无统计学意义(P=0.1615,>0.05)。3.0 T乳腺MR DWI的乳腺组织SNR为(52.28±19.34),1.5 T乳腺MR DWI的乳腺组织SNR为(49.97±17.99)。3.0 T乳腺MR DWI图像乳腺组织平均SNR略高于1.5 T,但二者差异无统计学意义(P=0.5500,>0.05)。3.0 T MR DWI的平均ADC值为(1.80±0.44)×10-3mm2/s,1.5 T MR DWI的平均ADC值为(1.73±0.32)×10-3 mm2/s,两者比较差异无统计学意义(P=0.0652,>0.05)。结论 DWI可用于3.0 T MR乳腺成像,图像质量可以达到1.5 T MR DWI的效果,且ADC值与1.5 T的ADC值无明显差异。     

DWI对局部进展期乳腺癌新辅助化疗疗效评价的初步研究

目的:探讨磁共振扩散加权成像(DWI)对局部进展期乳腺癌新辅助化疗疗效评价以及作为预测因子的可行性.方法:根据10例乳腺癌化疗后退缩情况将肿瘤分成缓解和进展两组,比较两组化疗前后ADC值和DWI信号强度的变化,并评价治疗前ADC值与化疗结束肿瘤退缩变化的相关性.结果:无论是治疗前还是治疗后,ADC值和DWI信号强度在缓解组和进展组间差异均无显著性意义(P＞0.05),但缓解组治疗后ADC值升高,而进展组则降低,尤其在b=1000和2000 s/mm2时明显.b=1000 s/mm2时,肿瘤高活性区和低活性区对治疗反应比较显示,肿瘤高活性区ADC值较低,治疗后ADC值升高(1.195±0.230和1.371±0.295);而肿瘤低活性区ADC值较高,治疗后ADC值反而下降(1.632±0.241和1.312±0.297);与病理对照显示,治疗后肿瘤细胞蜕变,并伴有明显的胶元和纤维化形成.治疗前ADC值与治疗后肿瘤退缩呈负相关,当b取1000和2000 s/mm2时相关更明显,前者为r= -0.802,P=0.005,后者的r = -0.745,P=0.013.结论:DWI可以对局部进展期乳腺癌新辅助化疗疗效作评价,并能对治疗疗效作出预测.     

3.0 T磁共振扩散加权成像及表观扩散系数在淋巴瘤诊断及随访中的应用价值

目的 观察恶性淋巴瘤的扩散加权成像(DWI)特征及表观扩散系数(ADC)值在治疗前后的变化,探讨 DWI及ADC值在淋巴瘤诊断和随访中的应用价值.资料与方法 恶性淋巴瘤初发患者15例,男8例,女7例,平均年龄48.7岁.其中10例化疗后进行复查;健康志愿者10名,男5名,女5名,平均年龄48.4岁.在3.0 T MRI上行常规MRI及DWI检查.在ADC图上分别测量恶性淋巴瘤患者及健康志愿者颈部淋巴结的ADC值.10例复查患者在初次检查相一致部位再次测量淋巴结的ADC值,并进行前后对比,同时与健康志愿者进行比较.采用PSS 11.0统计软件,对淋巴瘤患者及正常对照组淋巴结的ADC值进行独立样本的t检验.结果 DWI与常规T2WI脂肪抑制序列比较,DWI能更敏感、直观地显示淋巴结.15例恶性淋巴瘤患者平均ADC值(753.33±31.28)×10-3 mm2/s,化疗后复查,平均ADC值(1088.32±51.28)×10-3 mm2/s.化疗前后ADC值差异有统计学意义(t=5.79,P＜0.05).健康志愿者颈部淋巴结平均ADC值(1264.20±71.60)×10-3 mm2/s.15例淋巴瘤患者治疗前ADC值与健康志愿者差异有统计学意义(t=6.53,P＜0.05),治疗后ADC值与正常人差异无统计学意义(t=1.97,P＞0.05).结论 3.0 T磁共振DWI及ADC值测量为淋巴瘤的诊断及疗效的观察提供了有价值的信息.     

Diffusion-weighted MRI in a liver protocol: its role in focal lesion detection

AIM: To evaluate the role of diffusion-weighted imaging (DWI) in the detection of focal liver lesions (FLLs), using a conventional magnetic resonance imaging (MRI) protocol. METHODS: Fifty-two patients (22 males, average age 55.6 years, range: 25-82 years), studied using a 1.5 Tesla magnetic resonance scanner, were retrospectively analyzed; detection of FLLs was evaluated by considering the number of lesions observed with the following sequences: (1) respiratory-triggered diffusion-weighted single-shot echo-planar (DW SS-EP) sequences; (2) fat-suppressed fast spin-echo (fs-FSE) T2 weighted sequences; (3) steady-state free precession (SSFP) images; and (4) dynamic triphasic gadolinium-enhanced images, acquired with three-dimensional fast spoiled gradient-echo (3D FSPGR). Two radiologists independently reviewed the images: they were blinded to their respective reports. DW SS-EP sequences were compared to fs-FSE, SSFP and dynamic gadolinium-enhanced acquisitions using a t -test. Pairs were compared for the detection of: (1) all FLLs; (2) benign FLLs; (3) malignant FLLs; (4) metastases; and (5) hepatocellular carcinoma (HCC). RESULTS: Interobserver agreement was very good (weighted = 0.926, CI = 0.880-0.971); on the consensus reading, 277 FLLs were detected. In the comparison with fs-FSE, DW SS-EP sequences had a significantly higher score in the detection of all FLLs, benign FLLs, malignant FLLs and metastases; no statistical difference was observed in the detection of hepatocellular carcinoma (HCCs). In the comparison with SSFP sequences, DW SS-EP had significantly higher scores (P < 0.05) in the detection of all lesions, benign lesions, malignant lesions, metastases and HCC. All FLLs were better detected by dynamic 3D FSGR enhanced acquisition, with P = 0.0023 for reader 1 and P = 0.0086 for reader 2 in the comparison with DW SS-EP sequences; with reference to benign FLLs, DW SS-EP showed lower values than 3D FSPGR enhanced acquisition (P < 0.05). No statistical differences were observed in the detection of malignant lesions and metastases; considering HCCs, a very slight difference was reported by reader 1 (P = 0.049), whereas no difference was found by reader 2 (P = 0.06). CONCLUSION: In lesion detection, DWI had higher scores than T2 sequences; considering malignant FLLs, no statistical difference was observed between DWI and dynamic gadolinium images.     

动态增强磁共振成像结合扩散加权成像诊断乳腺病变的多参数分析

目的分析乳腺良、恶性病变的形态学及血流动力学表现,结合表观扩散系数(ADC)探讨动态增强MRI(DCE-MRI)结合扩散加权成像(DWI)对乳腺病变的诊断价值。资料与方法对236个乳腺良、恶性病灶的形态学表现、血流动力学表现及ADC值进行单变量及多变量分析,分析有意义的恶性征象,建立回归模型。结果对于肿块性病变,肿块边缘、内部增强特征、时间-信号强度曲线类型、ADC值及1min增强率在良、恶性病变中差异有统计学意义(P<0.05),边缘不光滑、毛刺征、内部增强不均匀、廓清型曲线、ADC值<1.15×10-3mm2/s、1min增强率>105%为恶性征象。对于非肿块性病变,时间-信号强度曲线类型、ADC值及1min增强率在良、恶性病变中差异有统计学意义(P<0.05);廓清型曲线、ADC值<1.35×10-3mm2/s、1min增强率>75%为恶性征象。肿块和非肿块性病变诊断模型的敏感性、特异性、阳性预测值、阴性预测值和诊断准确性分别为85.3%、84.6%、91.6%、74.6%、85.1%和82.0%、83.3%、91.1%、69.0%、82.4%。结论 DCE-MRI结合DWI诊断乳腺癌的敏感性和特异性高,有重要临床应用价值。     

An alternative explanation of the origin of the signal in diffusion-weighted MRI

I formulated an alternative explanation for the origin of the signal in diffusion-weighted MRI (DWI) and tested it in a simple experimental model using gelatin. My findings indicate that the signal in DWI is influenced by the passage of water from the sol to the gel state, independently of the presence of cell structures or membrane-dependent diffusion. Received: 4 April 1999/Accepted: 12 July 1999     

Diffusion-weighted MRI after cryosurgery of the canine prostate. Magnetic resonance imaging

PURPOSE: To evaluate the acute lesion created by cryosurgery with diffusion-weighted magnetic resonance imaging (DWI). MATERIALS AND METHODS: The appearance of the acute cryolesion was evaluated in four canine prostates DWI after they were warmed to original body temperature. The prostates were excised, stained with triphenyl tetrazolium chloride (TTC), photographed, prepared for hematoxylin and eosin (H&E) staining, and examined under a light microscope. RESULTS: A marked decrease in apparent diffusion coefficient of 38% was evident in the center of the previously frozen tissue, but not in all of the previously frozen tissue. Histologic results confirm differences between the iceball core and the periphery of the iceball, which have markedly different imaging characteristics on DWI. CONCLUSION: The core of the previously frozen tissue has a reduced apparent diffusion coefficient (ADC) compared to the periphery of the previously frozen tissue and previously unfrozen tissue.     

Evaluation of Malignant Breast Lesions Using High-resolution Readout-segmented Diffusion-weighted Echo-planar Imaging: Comparison with Pathology

Purpose:We aimed to investigate the performance of high resolution-diffusion-weighted imaging (HR-DWI) using readout-segmented echo-planar imaging in visualizing malignant breast lesions and evaluating their extent, using pathology as a reference.Methods:This retrospective study included patients who underwent HR-DWI with surgically confirmed malignant breast lesions. Two radiologists blinded to the final diagnosis evaluated HR-DWI independently and identified the lesions, measuring their maximum diameters. Another radiologist confirmed if those lesions were identical to the pathology. The maximum diameters of the lesions between HR-DWI and pathology were compared, and their correlations were calculated using Spearman’s correlation coefficient. Apparent diffusion coefficient (ADC) values of the lesions were measured.Results:Ninety-five mass/64 non-mass lesions were pathologically confirmed in 104 females. Both radiologists detected the same 93 mass lesions (97.9%). Spearman’s correlation coefficient for mass lesions were 0.89 and 0.90 (P < 0.0001 and 0001) for the two radiologists, respectively. The size differences within 10 mm were 90.3% (84/93) and 94.6% (88/93) respectively. One radiologist detected 35 non-mass lesions (54.7%) and another radiologist detected 32 non-mass lesions (50.0%), of which 28 lesions were confirmed as identical. Spearman’s correlation coefficient for non-mass lesions were 0.59 and 0.22 (P = 0.0002 and 0.22), respectively. The mean ADC value of mass lesions and non-mass lesions were 0.80 and 0.89 × 10⁻³ mm²/s, respectively.Conclusion:Using HR-DWI, malignant mass lesions were depicted with excellent agreement with the pathological evaluation. Approximately half of the non-mass lesions could not be identified, suggesting a current limitation of HR-DWI.     

乳腺癌的MRI成像技术及其诊断价值

目的:探讨乳腺癌的MRI特征表现,分析各种MR成像技术的临床应用价值和存在的不足.方法:38例乳腺癌患者术前均经MRI平扫、DWI、动态增强及1H-MRS检查,回顾性分析乳腺癌的MRI表现,并分析各种乳腺MR成像技术的应用价值及存在的不足.结果:在平扫T1WI、压脂T2WI乳腺癌多表现为等或低信号;DWI中b=0时病灶呈明显高信号,随b值增加病灶信号强度依次降低;以形状不规则、毛刺征、环形强化、早期增强率≥70%和Ⅱ型或Ⅲ型曲线作为诊断乳腺癌标准,其敏感度分别为65%、67.5%、80%、95%和95%;1H-MRS显示乳腺癌出现明显升高的Cho峰,Cho/Cr升高,基于Cho峰的出现诊断乳腺癌的敏感度为77.5%.结论:乳腺癌MRI病灶形态学、动态增强特点具有特征性,DW和1H-MRS检查具有重要的辅助诊断价值,但是部分良、恶性病灶的表现存在部分重叠,对乳腺导管原位癌的诊断MRI无明显优势.     

Diffusion-weighted whole-body MRI with background body signal suppression: technical improvements at 3.0 T

Purpose:

To improve image quality of diffusion‐weighted body magnetic resonance imaging (MRI) with background body signal suppression (DWIBS) at 3.0 T.

Materials and Methods:

In 30 patients and eight volunteers, a diffusion‐weighted spin‐echo echo‐planar imaging sequence with short TI inversion recovery (STIR) fat suppression was applied and repeated using slice‐selective gradient reversal (SSGR) and/or dual‐source parallel radiofrequency (RF) transmission (TX). The quality of diffusion‐weighted images and gray scale inverted maximum intensity projections (MIP) were visually assessed by intraindividual comparison with respect to the level of fat suppression and signal homogeneity. Moreover, the contrast between lesions/lymph nodes and background (C_lb) was analyzed in the MIP reconstructions.

Results:

By combining STIR with SSGR, fat suppression was significantly improved (P < 0.001) and C_lb was increased two times. The use of TX allowed the reduction of acquisition time and improved image quality with regard to signal homogeneity (P < 0.001) and fat suppression (P = 0.005).

Conclusion:

DWIBS at 3.0 T can be improved by using SSGR and TX. J. Magn. Reson. Imaging 2012;456‐461. © 2011 Wiley Periodicals, Inc.     

Diffusion-weighted MRI: role in detecting abdominopelvic internal fistulas and sinus tracts

Purpose:

To retrospectively determine the incremental value of diffusion‐weighted MR‐imaging (DW‐MRI) to T2‐weighted (T2w) images in diagnosis of internal fistulas (IFs) and sinus tracts (STs).

Materials and Methods:

Fourteen patients with 25 IFs and STs arising from the small bowel ( 20 ), colon ( 4 ) and biliary tract ( 1 ) were included. Two independent observers reviewed T2w images, T2w+DW‐MRI images and T2w+contrast enhanced T1‐weighted (CE T1w) images at three sessions to detect IF/ST based on a confidence scale of five. Sensitivity and confidence score of each session was compared.

Results:

10/25 (40%) and 9/25 (36%) IFs and STs were detected on T2w images by observer 1 and 2, respectively. Both observers detected 19/25 (76%) and 24/25(96%) IFs and STs on T2w+DW‐MRI and T2w+CE T1w images, respectively. Detection rate and confidence score improved significantly by combining T2w images with DW‐MRI or CE T1w images (reader 1 + 2: P ≤ 0.01). There was no significant difference between the IF/ST detection rate of T2w+DW‐MRI and T2w+CE T1 image combinations. Confidence scores with T2w+CE T1w images were significantly greater than DW‐MRI+T2w images (reader 1:P = 0.01; reader 2: P = 0.03).

Conclusion:

DW‐MRI showed additional value to T2w imaging for diagnosis of IF and ST. DW‐MRI can be a useful adjunct, especially for patients with renal failure. J. Magn. Reson. Imaging 2012;35:125‐131. © 2011 Wiley Periodicals, Inc.