颈动脉粥样硬化的高分辨力MRI研究

目的:评价高分辨力MRI在显示和评价颈动脉粥样硬化斑块方面的价值。方法:采用3in表面线圈,DIRT1WI、FSET2WI和3DTOF序列对19例患者及3例志愿者进行颈动脉高分辨力MRI成像,评价有无硬化斑块并对其初步分型。结果:MRI清晰显示15例31处颈动脉粥样硬化改变,包括颈总动脉4处,颈动脉分叉17处,颈内动脉9处及颈外动脉1处。硬化斑块在DIRT1WI、FSET2WI表现为管壁不规则增厚,根据其信号改变参照AHA分类分为Ⅲ型12个、Ⅳ～Ⅴ型11个,Ⅵ型2个,Ⅶ型6个。在显示血管壁改变方面DIRT1WI优于其它序列。结论:高分辨力MRI能清晰显示颈动脉粥样硬化改变,根据其信号改变能判断其组成成分及其性质,为临床选择治疗方案及预后提供帮助。     

颈动脉粥样硬化斑块的3.0T MR成像研究

目的 探讨3.0T MR成像对颈动脉斑块检出及定性的能力. 方法 32例经超声筛选的颈动脉斑块病人, 运用3.0T 磁共振仪行多序列(3D-TOF、FLASH-3D、TSE-DIR T_1WI、TSE- DIR PDWI-FS、DIR TSE-T_2WI-FS、TSE-T_2WI)扫描,对颈动脉斑块行高分辨MRI成像, 参照AHA修改的MRI动脉粥样硬化分型标准, 分析斑块的信号特征. 结果 32例共发现49个粥样斑块,其中30个斑块在所有序列上信号单一均匀;15个斑块在1个或多个序列上信号混杂, 其中7个斑块含有脂质核心信号;3个斑块含钙化信号;2个表现为血管腔内血栓形成,管腔闭塞.28个斑块可见厚纤维帽信号;13个表现为薄纤维帽信号特征;5个斑块表面不光滑.结论 在3.0T MR仪上运用多序列高分辨成像可以检出颈动脉粥样硬化斑块, 并在一定程度上可对其进行定性分析和定型.     

3.0T磁共振扩散加权成像在子宫内膜癌诊断中的价值

目的 探讨3.0T MR扩散加权成像(DWI)在子宫内膜癌诊断中的临床应用价值.方法 对48例子宫内膜癌患者和20例无子宫内膜病变者行盆腔T2WI和DWI,由2名MRI诊断医师采用盲法随机进行MRI阅片后,采用5分制评分,以受试者工作特征曲线(ROC)对比分析单纯T2WI与DWI结合T2WI诊断子宫内膜癌的敏感性和特异性,并对内膜癌和正常内膜的表观扩散系数(ADC)值进行定量分析.结果 2名医师单纯应用T2WI与DWI结合T2WI检出子宫内膜癌的ROC曲线下面积(Az)值分别为0.831与0.944、0.877与0.954,2名医师DWI结合T2WI对内膜癌诊断的准确性均高于单纯应用T2WI(P<0.05).Kappa一致性检验表明2名医师具有良好的一致性(Kappa值分别为0.843和0.898,P<0.01).子宫内膜癌和正常内膜的ADC值分别为(0.954±0.139)×10-3mm2/s、(1.468±0.161)×10-3mm2/s,子宫 内膜癌与正常内膜的ADC值间差异有统计学意义(t=-13.217,P<0.01).结论 3.0T MR-DWI作为常规T2WI的补充检查序列可以明显提高对子宫内膜癌的检出率.     

IDEAL序列在脊柱脂肪抑制中的应用

目的 比较IDEAL T2WI、FSE T2WI序列在脊柱脂肪抑制扫描中的应用价值.资料与方法 35例脊柱MRI检查患者(颈椎10例、胸椎8例、腰椎17例)同时采用IDEAL T2WI、FSE T2WI两种脂肪抑制序列扫描,对图像脂肪抑制质量进行主观评价分级评估并测量信噪比.结果 FSE T2WI脂肪抑制质量主观评价分级为颈椎( 1.30±0.48)级、胸椎(1.80±0.71)级、腰椎(2.30±0.69)级,而IDEAL T2WI序列颈、胸椎均为(3.00±0.00)级、腰椎为(2.80±0.56)级;FSE T2WI脂肪抑制序列信噪比平均值分别为颈( 8.73±4.66)、胸(11.33±9.27)、腰(6.81±10.15),IDEAL T2WI序列信噪比平均值分别为颈( 18.90±7.71)、胸(26.02±11.61)、腰(19.57±9.12),两序列信噪比差异有统计学意义(t=3.73、5.72、11.23,P＜0.05).结论 脊柱MRI脂肪抑制扫描IDEAL T2WI序列优于FSE T2WI序列,IDEAL T2WI序列能提供更均匀稳定的脂肪抑制效果,脊柱图像信噪比高,可清晰显示脊柱病变.     

运用3.0T MR高分辨多序列技术对颈动脉斑块分型的研究

目的:探讨3.0T MRI高分辨多序列成像对颈动脉斑块的定位和分型能力.方法:31例经超声筛选的颈动脉斑块患者,在3.0T磁共振仪上,采用相控阵颈部线圈和心电门控,行3D-TOF、T1WI、T2WI和PDWI横断面扫描,在颈总动脉、分叉部及颈内动脉3个部位,对斑块进行初步定性和分型.结果:25例共150个血管断面中,Ⅰ～Ⅱ型占34%,Ⅲ型占44.7%,Ⅳ～Ⅴ型占14%,Ⅵ型占3.3%,Ⅶ型占4.0%;Ⅶ型的钙化斑块均被CT所证实.不同类型斑块在颈动脉各部位的分布上差异无显著性意义(P=0.112).Ⅵ型病例近期均有同侧大脑半球颈动脉供血区缺血事件发生.结论:在3.0T MR上应用高分辨多序列技术能清晰显示颈动脉血管壁的细微结构和斑块的形态特征,对进展期斑块具有准确定位和初步分型能力,可作为一项无创性评价颈动脉粥样斑块的理想方法.     

高分辨多序列MR成像对颈动脉粥样硬化病变特征的可重复性研究

目的：前期研究已经证明，参照修改后的美国心脏协会标准，MRI能评价颈动脉粥样硬化的病变类型。本研究旨在评价读内或读间对使用高分辨、多序列磁共振成像评价颈动脉粥样硬化病变类型应用价值的认同度。方法：34位冠心病患(男29例，女5例，平均年龄53岁)均使用1．5T磁共振行4个序列扫描(T1WI、T2WI、质子加权、3D-时间飞跃血管成像)，参照MRI为基础的读内或读间认同的AHA标准，评价双侧颈动脉轴位影像的病变类型。     

多重对比MRI显示正常兔颈动脉

目的:探讨多重对比MRI(TOF、T1WI、T2WI、PDWI)技术显示正常兔颈总动脉方法的可行性及准确性。材料和方法:选择普通级新西兰大白兔20只,麻醉状态下分别对颈总动脉行多重对比序列MRI扫描和数字减影血管造影(DSA),选取相当于兔第三颈椎中间同一层面的图像资料,测量同一侧颈总动脉的血管直径作相关分析;同时将T1WI、T2WI及TOF原始图像传入工作站,用MIP及MPR方法进行血管重建分析。结果:MRI及DSA测量血管直径的平均数值分别为(2.42±0.15)mm和(2.15±0.08)mm,两者相关性具有统计学差异。T1WI、T2WI及TOF的MIP及MPR重建图像质量佳,重复性好。结论:多重对比MRI方法可以准确地及无创地评价兔颈总动脉的直径、血管壁信号,联合应用血管重建技术可以替代DSA来诊断及评价血管粥样硬化疾病,为建立兔颈动脉粥样斑块模型奠定基础,更加有助于探索人类颈动脉粥样硬化疾病的发生、发展以及与缺血性疾病之间的关系。     

MRI低信号分隔在乳腺纤维腺瘤诊断中的价值

目的评价MRI低信号分隔征在乳腺纤维腺瘤诊断中的价值。方法回顾性分析经手术病理证实的52例共54个乳腺纤维腺瘤的MRI表现特点,分析低信号分隔征的鉴别诊断价值。结果 54个乳腺纤维腺瘤中,37个纤维腺瘤在MRI可观察到低信号分隔,发生率为69%(37/54);其中29个病灶分隔厚度小于2mm,8个病灶厚度大于2mm。37个病灶低信号分隔在T1WI脂肪抑制序列均观察不清,33个病灶在T2WI脂肪抑制序列可观察到低信号分隔,在T1WI增强序列均可观察到。结论低信号分隔征是诊断乳腺纤维腺瘤较特异的征象之一,并且T1WI增强序列观察最佳。     

腹壁子宫内膜异位症的MRI表现

【摘要】目的：分析腹壁子宫内膜异位症(AWE)的MRI表现,为临床诊断提供依据。方法：搜集本院经病理证实的9例AWE患者的病例资料,分析MRI平扫及增强扫描影像特征。结果：9例AWE患者中,囊实混合型6例、实质型2例、囊肿型1例。MRI平扫表现：囊实混合型AWE T1WI呈不均匀等低信号,T2WI脂肪抑制序列呈等高混杂信号;实质型AWE T1WI呈不均匀低信号,T2WI脂肪抑制序列呈高、低混杂信号;囊肿型AWE T1WI呈稍低信号,T2WI脂肪抑制序列呈高信号。增强扫描表现：囊肿型的囊变部分无强化,实质性部分有明显强化,肿块病变范围均大于平扫,肿块边缘不规则,与正常组织分界不清。结论：出血、纤维化、钙化等多种混杂信号及增强扫描明显强化是腹壁子宫内膜异位症的特征性表现,结合手术史,腹部切口周围包块伴周期性疼痛有助于确诊。     

子宫腺肌症离体标本低场MRI研究

目的:分析子宫腺肌症离体标本的低场MRI表现,探讨子宫腺肌症的低场MRI诊断.材料和方法:采用OUTLOOK PROVIEW 0.23T MR对17例子宫腺肌症离体标本行采用矢状位T1WI、T2WI及irT2WI平扫并与病理进行对照分析.结果:子宫体积增大呈类球形,结合带增厚,厚度为10.4～28.6mm,平均15.2mm.病变主要位于子宫后壁肌层14例和前壁3例.所有标本,T2WI与irT2WI示子宫肌层内低信号区内夹杂斑片状高信号影,TIWI示子宫肌层内散在斑点状低信号影,6例标本肌层内少许斑点状高信号.T2WI/irT2WI呈高信号而T1WI呈低信号的病理上为异位的内膜岛,在T2WI与TIWI均呈高信号的为异位内膜出血灶.结论:低场MRI对子宫腺肌症诊断有重要价值,其能真实有效的反映出病变的病理特征,T2WI与irT2WI是病灶显示的敏感序列.     

精囊出血的MRI诊断(附5例报告)

目的 :分析精囊出血的MR表现 ,提高对精囊出血病变的认识。方法 :对 5例精囊出血的病例分别采用轴位T1WI、T2 WI、T1WI脂肪抑制序列及矢状位T2 WI序列行MR检查 ,并回顾性分析MRI表现。结果 :精囊出血表现为条状、结节状或纡曲短T1、长T2 异常信号 ,T1压脂后病灶显示更清晰并同周围组织区分开来。结论 :各种序列结合使用的MRI是精囊出血的可靠的非创伤性诊断手段。     

胰腺MRI:技术及诊断研究

目的 :探讨MR不同序列在胰腺病变诊断中的应用价值。方法 :84例胰腺检查包括 5 0例正常胰腺及 3 4例临床怀疑有病变的胰腺 ,其中包括 15例胰腺癌 ,2例胰岛细胞瘤 ,1例粘液性囊腺瘤 ,4例胰周肿瘤 ,12例胰腺炎。MR扫描序列包括常规SET1WI ;FSET2 WI ;增强前、后的脂肪抑制T1WI和GRE。结果 :3 4例异常胰腺中的 2 7例 ,增强前、后T1WI脂肪抑制像提供了最好的诊断信息 ,其次为增强后立即扫描的GRE像。未增强的GRE像极好地显示了急性胰腺炎的特征 ,SET2 WI像对胰岛细胞瘤及胰腺癌的肝转移显示较为敏感。结论 :增强前、后T1WI脂肪抑制序列及动态增强的GER序列 ,应为胰腺MRI的标准序列。     

MR imaging in carotid artery atherosclerosis plaque characterization.

AIM: To evaluate the potential role of carotid artery atherosclerosis plaque magnetic resonance (MR) microimaging as magnetic resonance imaging (MRI) marker, ex vivo MR images were acquired at optimized parameters on 9.4T Bruker animal imager for occluded tissue resected by carotid endarterectomy (CEA) and corresponding histopathological analysis was made. METHODS AND MATERIALS: For imaging, CEA tissues of size 2-6 cm long and 0.5-1.5 cm wide, were transferred to 15 ml co-polymer laboratory culture tubes containing either 10% formalin in phosphate buffered saline (PBS) or in 50% glycerol in PBS. Imaging protocol was set at TE=30 ms, TR=1.5 s, matrix size=265 x 512, NEX=128, slice thickness=1 mm and in-plane resolution=0.1 mm for total sample size 2.5 cm. Soon after imaging done, carotid artery tissues were cut into 5-mm segments and processed for histological section for successive 5-micrometer slices. To compare morphology of 5 mum thin CEA section with that of 1 mm MR slices, registration was obtained between histologic sections and MR slices. Contrast and magnetic resonance relaxation characteristics were analyzed. RESULTS: Total carotid artery area computed by MR imaging was correlated with areas determined from histologic sections (r(2)=0.989, p=0.0001). For the lumen area, the correlation between MR images and histologic area was (r(2)=0.942, p=0.0001). Relaxation times and T(2) parametric images of different plaque components were determinant for contrast resolution. Scan parameters were optimized for fibrous cap and atheroma. Scan parameters were characteristic for comparison at 1.5T and 9.4T MR imagers. CONCLUSION: The observed correlation validated MR microimaging to assess morphological features of carotid artery plaques and contrast resolution highlighted the potential of in vivo MR imaging as non-invasive MRI marker to monitor carotid artery plaque morphometry and plaque composition.     

Diagnostic value of gadolinium-enhanced dynamic MR imaging for parotid gland tumors

Objective

This study aimed to evaluate the value of gadolinium-enhanced dynamic MR imaging for differentiating benign and malignant parotid gland tumors, and for characterizing the various histological types.

Patients and methods

Non-enhanced T1-weighted (T1-W), fat-suppressed T2-weighted (T2-W), and gadolinium-enhanced fat-suppressed dynamic T1-weighted images were obtained preoperatively in 27 patients (28 parotid gland tumors), by using a 1.5 or 3 T MR imaging unit (GE, Signa Exite). The tumor margins and the enhancement curve patterns on dynamic MR imaging were analyzed. All patients underwent a parotidectomy with histopathologic analysis.

Results

Pleomorphic adenomas depict a gradual enhancement pattern. Warthin’s tumors depict an early peak of enhancement and a high washout pattern. Malignant tumors depict an early peak of enhancement and a low washout pattern.

Conclusion

Gadolinium-enhanced dynamic MR imaging improved the performance of MR imaging in differentiating benign from malignant parotid gland tumors and characterizing the different histological types of benign tumors.     

Cross-sectional imaging of primary osseous hemangiopericytoma

The aim of this study was to assess cross-sectional imaging features and the value of CT and MRI in primary hemangiopericytoma of bone. In five patients with histologically proven primary osseous hemangiopericytoma CT and MR scans were evaluated retrospectively. Both CT and MRI were available in four patients each. In three patients both imaging techniques were available. On CT primary hemangiopericytoma of bone presents as an expansive lytic lesion with bone destruction and inhomogeneous contrast enhancement. Magnetic resonance imaging depicts osseous hemangiopericytoma as hyperintense lesion on T2-weighted images with intermediate signal intensity on T1-weighted images. Curvilinear tubular structures of signal void in the tumor matrix on T1-weighted images and corresponding hyperintense structures on T2-weighted and on fat-suppressed short tau inversion recovery images were present in three patients. Although cross-sectional imaging findings are non-specific, they add to the diagnosis and provide valuable information about the extent of bone destruction and local tumor spread in patients with primary osseous hemangiopericytoma. While CT demonstrates the extent of bone destruction best, MRI better visualizes medullary and soft tissue extension of the tumor. Curvilinear signal abnormalities support the diagnosis of hemangiopericytoma of bone. This imaging pattern is best visualized on fat-suppressed or contrast enhanced T1-weighted MR images.     

The MRI of extraadrenal pheochromocytoma in the abdominal cavity

The purpose of this study was to summarize the MR appearances of extraadrenal pheochromocytoma in the abdominal cavity and evaluate the capabilities of MRI in diagnosis of the tumor. Eleven consecutive patients with an extraadrenal pheochromocytoma in abdominal cavity who underwent preoperative 0.5 T (n=5) or 1.5 T (n=6) superconductor MRI and had a surgical resection were enrolled in the study. The MR scanning protocol included axial T(2)-weighted imaging with or without fat-suppressed sequences, axial and coronal uncontrast and contrast T(1)-weighted sequences with or without fat suppression. The extraadrenal pheochromocytomas were found in retroperitoneum (n=5), the urinary bladder (n=1), the pelvis (n=1), the right prerenal area (n=1), the renal hilus (n=1), the left paramusculus psoas major (n=1) and liver (n=1). The mean maximal diameter of tumors was 55.9 mm (range 17.8-162.2 mm). The high signal intensity was seen on T(2)-weighted imaging in all tumors compared to muscle or liver, especially with fat suppression. The intratumoral septa and capsules were shown in 63.6% and 72.7% of cases, respectively, which had low signal intensity on T(2)-weighted imaging. These relative characteristics may be helpful for qualitative diagnosis of extraadrenal pheochromocytomas with MRI. Other usefulness of MRI was to locate the position, to decide the range of tumors and to show well the relationship between the tumor and near structures.     

3.0 T MR扩散加权成像评价兔肝VX2瘤射频消融治疗的实验研究

目的 探讨3.0 T MR DWI评价兔肝VX2瘤射频消融治疗疗效的价值.方法 新西兰大白兔22只.20只用于建立VX2瘤模型,2只健康正常兔用于行正常肝射频消融术对照.于VX2瘤种植后14～21 d(平均17 d),对符合实验条件瘤兔(病灶位于肝实质内,最大直径≤3 cm,坏死病灶直径≤整个病灶直径的1/2)行3.0 T常规MRI和功能DWI.对瘤兔及对照组正常兔行射频消融治疗,射频消融术后7～10 d(平均8 d)行3.0 T常规MRI及DWI.所有射频消融治疗兔行MR检查后均行病理检查.测量兔肝VX2瘤、正常兔肝射频消融治疗前后ADC值,分析兔肝VX2瘤射频消融治疗前后3.0 T MR常规成像、ADC值特征,并与病理对照.同一b值射频消融治疗后不同组织间ADC值比较采用重复测量资料方差分析.结果 20只实验组兔肝VX2瘤模型均建立成功,1例肿瘤突出于肝表面、1例肿瘤病灶出现明显坏死未纳入实验.所有18个瘤灶及2例正常兔肝射频消融均成功.兔VX2瘤T1WI序列表现为低或等信号,T2WI为高信号.肝VX2瘤兔射频消融治疗后7～10 d,射频消融病灶T1WI序列表现为低或稍高信号,T2WI为混杂信号.T2WI序列周边环形稍高信号为肉芽组织,增强扫描明显强化,T2WI序列低、中等信号为凝固性坏死.坏死组织在DWI图上为低信号,活性肿瘤组织位于病灶周边,呈结节状,在T2WI、DWI图上为等或稍高信号.肿瘤标本为灰白色,部分肿瘤组织间夹杂增生血管、少许肉芽组织.b值为600 s/mm2时,射频消融治疗后活性肿瘤组织(9只)、坏死组织(18只)、肉芽组织(18只)、正常组织(18只)ADC值分别为:(1.227±0.140)×10-3、(0.702±0.050)×10-3、(1.918±0.124)×10-3、(1.739±0.044)×10-3mm2/s,各组间ADC值差异具有统计学意义(P＜0.01).b值分别为200、400、600、800、1000 s/mm2时治疗后坏死组织、活性残留或复发肿瘤组织、肉芽组织、正常肝组织间ADC值差异具有统计学意义(P＜0.01).结论 兔VX2瘤模型适合3.0 T MR评价射频消融治疗疗效的动物实验研究,对射频消融治疗基础及临床应用研究具有重要价值.     

Evaluation of locally recurrent pelvic malignancy: performance of T2- and diffusion-weighted MRI with image fusion

PURPOSE: To evaluate the performance of T2- and diffusion-weighted magnetic resonance imaging (MRI) with image fusion for detection of locally recurrent pelvic malignancy. MATERIALS AND METHODS: The study group consisted of 28 patients (27 female, 1 male) who underwent pelvic MRI at 1.5 T after treatment of pelvic malignancy. MR images were reviewed independently by three blinded readers. The performance of the four sequences for detecting local recurrence was evaluated using receiver operating characteristic analysis: T2-weighted fast spin-echo (FSE), diffusion-weighted echo-planar imaging (DWI), dynamic contrast-enhanced (DCE) fat-suppressed T1-weighted spoiled gradient echo (SPGR), and T2-DWI with image fusion, the latter created using OsiriX Medical Imaging Software. RESULTS: Local recurrence was confirmed at biopsy in 16 patients. Twelve patients showed no evidence of recurrence on two consecutive MRI studies. The Az value for T2-DWI with image fusion (0.949) was statistically greater than that for T2-weighted FSE (0.849) (P<0.05). The sensitivity and specificity was 87.5% and 47.2%, respectively, for T2-weighted FSE, 100.0% and 50.0% for DWI, 95.8% and 58.3% for DCE fat-suppressed T1-weighted SPGR, and 93.8% and 72.2% for T2-DWI with image fusion. CONCLUSION: For depicting locally recurrent pelvic malignancy, T2-DWI with image fusion outperforms standard T2-weighted FSE and DWI and is comparable to DCE fat-suppressed T1-weighted SPGR.     

MR evaluation of arrhythmogenic right ventricular cardiomyopathy in pediatric patients

OBJECTIVE: The aim of our study was to correlate the findings of three MR imaging sequences with the clinical findings of possible arrhythmogenic right ventricular cardiomyopathy in pediatric patients. MATERIALS AND METHODS: Twenty-six consecutive pediatric patients underwent MR imaging with ECG-gated non-breath-hold spin-echo T1-weighted non-fat-suppressed and fat-suppressed sequences. The MR images were evaluated for thinning or fat signal in the right ventricular wall and for enlargement or increased trabeculation of the right ventricle or right ventricular outflow tract. Cine MR imaging was used to assess wall motion abnormalities. Cardiac biopsy was performed in 17 patients. Biopsy results and other clinical findings suggesting arrhythmogenic right ventricular cardiomyopathy were tabulated. RESULTS: Two MR imaging studies were of poor quality as a result of arrhythmias, and one study was incomplete. In the 23 remaining patients, there were (mean +/- SD) 1.5 +/- 1.0 and 0.8 +/- 1.0 findings of possible arrhythmogenic right ventricular cardiomyopathy in the non-fat-suppressed and the fat-suppressed sequences, respectively. Fat-compatible signal in the myocardium was detected in 16 (70%) of 23 non-fat-suppressed studies and in five (22%) of 23 fat-suppressed studies (p = 0.003). The non-fat-suppressed sequence had a higher sensitivity (75% vs 43%) and a lower specificity (38% vs 75%) for fatty infiltration than did the fat-suppressed sequence when correlated with the biopsies. The linear correlation between all MR findings and all clinical diagnostic criteria, including biopsy, was better for the combination of cine and both T1 sequences (r = 0.58) than for the non-fat-suppressed (r = 0.53) or fat-suppressed (r = 0.46) T1 sequences alone. CONCLUSION: MR imaging showed moderate correlation with the clinical criteria in the diagnosis of arrhythmogenic right ventricular cardiomyopathy.     

Head and neck paragangliomas: improved tumor detection using contrast-enhanced 3D time-of-flight MR angiography as compared with fat-suppressed MR imaging techniques

BACKGROUND AND PURPOSE: MR imaging techniques have proved their efficacy in imaging the head and neck region. In this study, we compared T1-weighted, dual T2-weighted, and fat-suppressed MR imaging and unenhanced and contrast-enhanced 3D time-of-flight MR angiography sequences for detection of head and neck paragangliomas. METHODS: Thirty-one patients with 70 paragangliomas were examined. Four combinations of MR images were reviewed by two neuroradiologists: T1-weighted and dual T2-weighted fast spin-echo images, T1- and T2-weighted fat-suppressed fast spin-echo images, T1-weighted and contrast-enhanced T1-weighted fat-suppressed spin-echo images, and unenhanced and contrast-enhanced 3D time-of-flight MR angiograms. The randomized examinations were independently evaluated for image quality, presence of tumor, tumor size, and intratumoral flow signal intensity. The standard of reference for presence of tumor was digital subtraction angiography. Data were analyzed by using the logistic regression method. RESULTS: Mean sensitivity, specificity, and negative predictive values, respectively, were assessed by the two observers to be as follows: for dual T2-weighted fast spin-echo, 74%/99%/86%; for T2-weighted fat-suppressed fast spin-echo, 70%/100%/85%; for contrast-enhanced T1-weighted fat-suppressed spin-echo, 73%/100%/86%; and for unenhanced and contrast-enhanced 3D time-of-flight MR angiography, 89%/99%/93%. Sensitivity was significantly better for unenhanced and contrast-enhanced 3D time-of-flight MR angiography (P =.000028). More intratumoral flow signal intensity was depicted with unenhanced and contrast-enhanced 3D time-of-flight MR angiography. CONCLUSION: A combination of unenhanced and contrast-enhanced 3D time-of-flight MR angiography is superior for detecting paragangliomas and should be added to a standard imaging protocol, especially for patients with familial paragangliomas because they are more susceptible to multicentric disease.