增强MRA及超声在TIA血管病变中的价值

目的:探讨增强MRA及超声对短暂性脑缺血发作(TIA)病人颈部动脉血管病变的诊断价值.方法:对48例TIA患者分别应用血管彩超、增强MRA检查颈部动脉血管,对检出病变部位、数量进行分析.结果:超声对椎动脉、颈总动脉、颈内动脉的病变检出率分别是27.1%、88.5%、17.7%.3D TRICKS对椎动脉、颈总动脉、颈内动脉的病变检出率分别是77.1%、20.8%、19.8%.应用χ2检验,对椎动脉和颈总动脉病变的检出率,增强MRA和超声之间有显著差异(P均小于0.001);对颈内动脉病变的检出率,增强MRA和超声之间无统计学差异(P>0.05).结论:对于TIA患者,超声可以作为初筛检查.超声与增强MRA联合检查,可以更全面、准确的评价血管病变,指导临床治疗.     

三维对比增强MR血管成像在颈部血管病变中的应用

目的探讨三维对比增强MR颈部血管成像（3D—CE—MRA）的方法及临床应用价值。方法对87例患者行颈部血管3D—CE-MRA检查,双日检查者采用testbolus＋3D—CE—MRA扫描,共检查49例患者,单日检查者采用carebolus＋3D—CE—MRA扫描,共检查38例患者,评价图像质量并分析病变血管情况．结果87例患者采用两种方法扫描图像质量无明显差异,均能满足临床诊断需要,3D—CE—MRA图像清楚显示了血管病变部何肢性质。结论3D—CE—MRA是无创、安全、便捷、可靠的颈部血管病变的检查方法,可以代替诊断性的DSA。     

实时触发动态增强MR颈动脉成像的临床应用

目的:探讨实时触发三维动态增强MR颈动脉成像的方法及其临床应用价值。方法:采用实时触发(care-bolus)快速梯度回波序列对62例疑有颈动脉病变的患者进行三维动态增强MR颈动脉成像。原始图像经最大信号投影(MIP)处理,根据MRA图像对病变血管及正常血管的显示情况采用优、良、差3级,对MRA图像质量进行评价。结果:所有检查病例图像质量均达到优良,能清晰显示正常解剖血管结构及病变情况。62例中有33例发现血管病变,MRA结果与手术(n=10)、DSA(n=5)和/或多普勒超声(n=33)结果一致。结论:实时触发三维动态增强MR颈动脉成像能较好显示颈部血管情况,是一种简便易行、有效的颈部血管检查方法。     

颈动脉三维增强磁共振血管成像技术初步探讨

目的　探讨颈动脉三维增强磁共振血管成像 (3DCEMRA)方法和影响图像质量的因素。方法　使用 1.5T超导型MR扫描机 ,头部、颈部以及部分腰椎相控阵线圈。对 48例病人进行颈动脉 3DCEMRA增强扫描。检查时 ,嘱患者屏气 ,于静脉内团注钆双胺 (Gd -DTPA -BMA)对比剂后进行颈动脉期扫描 ,用 3DFLASH序列采集图像。结果　检查的病例 96%获得了满意的图像 ,经MIP和MPR重建后 ,能够清楚显示颈动脉正常解剖结构和病变的部位、大小及其狭窄程度。 2 3例经数字减影血管造影(DSA)或 /和超声以及手术证实的病例中 ,3DCEMRA显示颈动脉的特异性和敏感性均为 10 0 %。结论　高质量的颈动脉MRA图像依赖于注药后扫描时机的准确性 ,注药流速与总量的合理性 ,合适的扫描序列 ,以及操作者的技巧和熟练程度     

颌颈巨大肿物的颈动脉CTA和MRA的对比研究

目的对比分析颈动脉CT血管成像(CTA)和核磁共振血管成像(MRA)在头颈部的成像特点,探讨颈部巨大肿物对颈动脉正常解剖位置的影响和对血管壁侵蚀的价值。材料和方法术前对11例颌颈部肿物患者行颈动脉CTA和MRA,分别同步注射造影剂,螺旋CT对病变区血管段进行重点薄层螺旋扫描,EasyVision三维重建;MRI扫描由Sun工作站三维重建。对比分析颈动脉CTA和MRA。结果11例颌颈部肿物患者中5例颈总动脉、颈内动脉向内侧移位,其中2例颈外动脉受压狭窄;另1例颈内动脉向后侧移位,颈外动脉向外前移位;1例颈内静脉血管壁多处受侵蚀。结论CTA能够显示颈部大血管走向及与下颌骨、舌骨、颈椎、颅底骨组织三维空间关系;MRA显示血管壁的情况较CTA精确,均可为诊断和手术入路提供三维信息。     

颈动脉粥样硬化磁共振血管成像和彩色多普勒超声对比研究

目的 探讨彩色多普勒和磁共振血管成像(MRA)对颈动脉粥样硬化的诊断价值.方法 用CDFI及MRA 2种方法检查42例缺血性脑梗塞患者和40例对照组的颈动脉.超声检查颈动脉内径、测量颈动脉内膜-中层厚度(IMT)、最狭窄处管径,了解斑块情况,观察颈动脉狭窄程度.MRA检查颈动脉内径,测量病变动脉信号缺失情况,判断颈动脉狭窄程度.结果 超声检查显示缺血性脑梗塞患者颈动脉病变发生率明显高于对照组(P＜0.001).本组病例轻度、重度狭窄的MRA与超声诊断完全符合.1例血管闭塞超声低估为重度狭窄,1例超声判断为中度狭窄MRA高估为重度狭窄.MRA和超声结果具有极好的一致性.结论 超声与MRA在诊断颈动脉狭窄中具有互补作用,两者结合使用能提高评估狭窄程度的准确性.     

三段移床三维增强MRA在腹盆及下肢血管病变中的应用

目的　探讨三段移床三维增强MRA 1次全程显示腹盆及下肢血管树的技术及其在血管病变诊断中的作用。方法　 12例腹盆及下肢血管病变的患者 ,男 8例 ,女 4例。 10例同时做了动脉和静脉成像 ,其中动脉血栓形成 5例 ,动脉硬化性闭塞性脉管炎 6例 ,静脉血栓形成 7例 ,下肢静脉炎 3例。其中 5例经DSA证实 ,5例手术证实。扫描序列采用三维快速SPGR序列 ,移床三段扫描。结果　靶血管显示优 9例 ,良 3例。有手术或DSA结果 10例中 ,共有病变段 3 4段 ,其MRA诊断与DSA或手术符合率为 85 .3 %。结论　移床三维增强MRA能使腹主动脉及两侧髂动脉分叉到小腿动脉全程显影 ,还可显示静脉。侧枝循环情况显示优于DSA ,是一种前途广阔的简便的血管检查新方法。     

三维对比剂增强MR血管成像对颈部动脉病变的诊断价值

目的　分析三维对比剂增强MR血管成像 (3DCE MRA)显示的颈部动脉常见病变 ;与DSA比较 ,明确 3DCE MRA诊断颈部动脉病变的价值。方法　对 741例超声多普勒怀疑颈部动脉疾病的患者进行 3DCE MRA成像 ,并根据其病变表现总结分类。 2 0 6例病人同时行DSA检查 ,将颈部动脉分为颈总、颈内、颈外、锁骨下及椎动脉 5个部位 ,由 2位放射学专家独立评估DSA及 3DCE MRA血管资料。结果　 3 6 7%病例 (2 72 / 741)显示无异常。 63 2 9% (469/ 741)显示颈部动脉有病变 ,共计 82 7段 ,其中动脉粥样斑块占 3 4 2 2 % (2 83段 ) ,动脉狭窄占 3 4 46% (2 85段 ) ,动脉闭塞占 3 3 8% (2 8段 ) ,动脉发育纤细占 14 87% (12 3段 ) ;动脉开口变异占 3 87% (3 2段 ) ,动脉扭曲占 3 63 % (3 0段 ) ,动脉瘤占 0 72 % (6段 ) ,动脉夹层占 1 2 1% (10段 ) ,肿瘤包绕或推压动脉占 1 45% (12段 ) ,术后复查占2 18% (18段 )。对 2 0 6例的 412段血管与DSA比较 ,3DCE MRA在颈总动脉、颈内动脉及椎动脉的阳性检出率差异有显著性意义 (P <0 0 1) ,主要是对动脉粥样斑块 (2 56段与 2 83段 )和动脉狭窄 (2 58段与 2 85段 )存在一定的高估。但对 412段血管整个样本 ,两种方法在同一部位诊断各种血管病变差异无显著性意义 (P >0 0     

颈动脉体瘤的多层螺旋CT血管造影(附3例报告)

颈动脉体瘤(carotid body tumor，CBT)是颈部副神经节瘤之一，是一种较少见的颈动脉间隙肿块。DSA被认为是诊断CBT的主要指标之一，原因在于其能准确显示CBT的供血动脉、肿瘤血管细节以及病变与血管的整体关系。三维时间飞跃法磁共振血管造影(three-dimensional time-of—flight magnetic resonance angiography，3D TOF MRA)以及彩色多普勒超声     

三段移床增强MRA显示腹盆及下肢血管树的技术探讨

目的：探讨三段移床三维增强MRA一次全程显示腹盆及下肢血管树的技术及其在血管病交诊断中的作用。方法：10例髂及下肢血管病交的患者，9例同时做了动脉和静脉成像，其中动脉血栓形成3例，动脉硬化性闭塞性脉管炎3例，伴有静脉血栓形成者7例，其中6例经DSA或手术证实。扫描序列采用三维快速SPGR序列，移床三段扫描。结果：靶血管显示优7例，良3例，病变段共32例段，其中有手术或DSA结果6例中，共有病变段26段，其影像诊断与DSA和手术相符者为22段，符合率为84．6％。结论：移床三维增强眦能使腹主动脉及两侧髂动脉分叉到小腿动脉全程显影，更直观、更全面的显示髂及下肢血管病变，是一种前途广阔的简便的血管检查新方法。     

颈性眩晕患者的血管影像学研究

目的：分析颈性眩晕的影像学特点,并评价彩色超声多普勒(CDUS)联合 CT 血管成像(CTA)、增强磁共振血管成像(CE-MRA)在颈性眩晕中的应用价值。方法62例临床诊断为颈性眩晕患者作为病例组,其中39例行颈部血管超声和颈部 CTA检查,23例行颈部血管超声和颈部 CE-MRA。选取30例正常志愿者作为对照组,其中18例行颈部血管超声和颈部 CTA 检查,12例行颈部血管超声和颈部 CE-MRA。评价2组间椎动脉血流动力学及形态学的情况。比较 CDUS 与 CTA/CE-MRA 对椎动脉形态学检测的差异。结果①在形态学方面：颈性眩晕组中椎动脉狭窄率(46.77%)及变异率(29.03%)均高于对照组椎动脉狭窄率(23.33%)及变异率(6.67%),差异有统计学意义(均 P <0.05)。颈性眩晕组椎动脉迂曲发生率(11.29%)与对照组(13.33%)比较,差异无统计学意义(P >0.05)。②在血流动力学方面：CDUS 显示颈性眩晕组血流下降发生率(66.13%)高于对照组(10.00%),差异有统计学意义(P<0.05)。颈性眩晕组椎动脉狭窄(86.21%)及变异者(72.22%)血流速度下降发生率明显高于椎动脉迂曲(28.57%)及椎动脉正常者(12.50%)。结论应用 CDUS 联合 CTA/CE-MRA,可从责任血管形态学、血流动力学方面综合评价颈性眩晕的病因,对颈性眩晕的诊治具有重要意义。     

Follow-up of intracranial aneurysms selectively treated with coils: Prospective evaluation of contrast-enhanced MR angiography

BACKGROUND AND PURPOSE: The aim of this study was to determine the feasibility and usefulness of contrast-enhanced MR angiography (CE-MRA) for the follow-up of intracranial aneurysms treated with detachable coils, by comparing CE-MRA with digital subtraction angiography (DSA) and 3D time-of- flight (TOF) MRA. METHODS: Thirty-two patients with 42 treated aneurysms were included in the study; 6 had been treated for multiple aneurysms. All MRAs were performed with a 1.5T unit within 48 hours of DSA. We performed 2 types of acquisition: a 3D TOF sequence and CE-MRA. Twenty-eight patients were included 1 year after endovascular treatment, and 4 patients, after 3 years or more. DSA was the technique of reference for the detection of a residual neck or residual aneurysm. RESULTS: Compared with DSA, the sensitivity of MRA was good. For the detection of residual neck, there was no significant difference between the results of 3D TOF MRA (sensitivity, 75%-87.5%; specificity, 92.9%, according to both readers) and CE-MRA (sensitivity, 75%-82.1%; specificity, 85.7%-92.9%). For the detection of residual aneurysm, sensitivity and specificity of both techniques were the same, respectively 80%-100% and 97.3%-100%. Therefore, CE-MRA was not better than 3D TOF MRA for the detection of residual neck or residual aneurysm. For large treated aneurysms, there was no difference between decisions regarding further therapy after CE and 3D TOF MRA, even though CE-MRA with a short echotime and enhancement gave fewer artifacts and better visualization of recanalization than 3D TOF MRA. The interpretation of transverse source images and the detection of coil mesh packing seemed easier with 3D TOF imaging. CONCLUSION: This prospective study did not show that CE-MRA was significantly better than 3D TOF MRA for depicting aneurysm or neck remnants after selective endovascular treatment using coils. For aneurysms treated with coils, 3D TOF MRA seems a valid and useful technique for the follow-up of coiled aneurysms.     

Comparison of 3D TOF-MRA and 3D CE-MRA at 3 T for imaging of intracranial aneurysms

Purpose

To compare 3 T elliptical-centric CE MRA with 3 T TOF MRA for the detection and characterization of unruptured intracranial aneurysms (UIAs), by using digital subtracted angiography (DSA) as reference.

Materials and methods

Twenty-nine patients (12 male, 17 female; mean age: 62 years) with 41 aneurysms (34 saccular, 7 fusiform; mean diameter: 8.85 mm [range 2.0–26.4 mm]) were evaluated with MRA at 3 T each underwent 3D TOF-MRA examination without contrast and then a 3D contrast-enhanced (CE-MRA) examination with 0.1 mmol/kg bodyweight gadobenate dimeglumine and k-space elliptic mapping (Contrast ENhanced Timing Robust Angiography [CENTRA]). Both TOF and CE-MRA images were used to evaluate morphologic features that impact the risk of rupture and the selection of a treatment. Almost half (20/41) of UIAs were located in the internal carotid artery, 7 in the anterior communicating artery, 9 in the middle cerebral artery and 4 in the vertebro-basilar arterial system.All patients also underwent DSA before or after the MR examination.

Results

The CE-MRA results were in all cases consistent with the DSA dataset. No differences were noted between 3D TOF-MRA and CE-MRA concerning the detection and location of the 41 aneurysms or visualization of the parental artery. Differences were apparent concerning the visualization of morphologic features, especially for large aneurysms (>13 mm). An irregular sac shape was demonstrated for 21 aneurysms on CE-MRA but only 13/21 aneurysms on 3D TOF-MRA. Likewise, CE-MRA permitted visualization of an aneurismal neck and calculation of the sac/neck ratio for all 34 aneurysms with a neck demonstrated at DSA. Conversely, a neck was visible for only 24/34 aneurysms at 3D TOF-MRA. 3D CE-MRA detected 15 aneurysms with branches originating from the sac and/or neck, whereas branches were recognized in only 12/15 aneurysms at 3D TOF-MRA.

Conclusion

For evaluation of intracranial aneurysms at 3 T, 3D CE-MRA is superior to 3D TOF-MRA for assessment of sac shape, detection of aneurysmal neck, and visualization of branches originating from the sac or neck itself, if the size of the aneurysm is greater than 13 mm. 3 T 3D CE-MRA is as accurate and effective as DSA for the evaluation of UIAs.     

3.0T高分辨率CE-MRA对颈部血管狭窄的诊断价值

目的探讨三维对比增强磁共振血管成像(3D CE-MRA)在颈部动脉血管狭窄诊断中的临床应用价值。方法对23例临床拟诊颈部动脉血管狭窄行数字减影血管造影(DSA)的患者行颈部3D CE-MRA。将两种方法检查结果进行相关性比较。结果 23例患者共230个节段血管,3D CE-MRA显示了227个节段,共诊断出74处(32.6%)狭窄,其中28处轻度狭窄,22处中度狭窄,20处重度狭窄,4处闭塞;DSA共显示了230个节段的血管,共诊断出69处(30.4%)血管狭窄,其中24处轻度狭窄,23处中度狭窄,19处重度狭窄,3处闭塞。与DSA相比,3DCE-MRA对颈部动脉轻度、中度、重度狭窄及动脉闭塞的显示敏感性均为100%,特异性分别为85.71%、90.91%、90%和75%,两种检查方法对颈部动脉狭窄程度的判断有良好的一致性(κ=0.921,P=0.000)。结论 3.0T 3DCE-MRA能够可靠的评价颈部动脉狭窄性病变,基本可以替代DSA检查。     

三维增强磁共振血管成像在糖尿病足病外周动脉病变中的应用

目的:探讨3D CE MRA在糖尿病足病外周动脉病变检查中的成像方法及应用价值。方法:对17例临床怀疑外周动脉病变的糖尿病足病患者,运用MR 3D FLASH自减影序列行CE MRA检查,检查范围自腹主动脉下段至足背动脉,对靶血管作最大强度投影(MIP)重组。另对其中4例小腿及足部动脉单独行二次增强扫描(Gd-DTPA 15ml,2.5ml/s)。对外周动脉进行观察,分析其狭窄情况并分级。结果:所有患者显示目标动脉基本满意,血管解剖形态较清晰,病变显示较明确。正常或轻度狭窄169个节段,中度狭窄94个节段,重度狭窄45个节段,闭塞49个节段。结论:3D CEMRA在糖尿病足病外周动脉病变检查中具有重要意义,但尚有一定局限性。     

Accuracy of semiautomated analysis of 3D contrast-enhanced magnetic resonance angiography for detection and quantification of aortoiliac stenoses

OBJECTIVES: We sought to compare reproducibility and accuracy of semiautomated stenosis detection and quantification in 3D contrast-enhanced magnetic resonance angiography (CE-MRA) images with conventional evaluation of 3D CE-MRA in patients with peripheral arterial disease (PAD) by using intra-arterial digital subtraction angiography (IA-DSA) as standard of reference. METHODS: Twenty-five patients with PAD underwent CE-MRA and IA-DSA. Three blinded observers independently evaluated CE-MRA datasets for stenoses in the aortoiliac region using semiautomated computer analysis. Semiautomated measurements were compared with conventional measurements of stenosis on CE-MRA datasets, as measured by 3 other independent observers blinded to all other measurements. Interobserver agreement was quantified using kappa (kappa) and intraclass correlation coefficients (ICCs). Sensitivity and specificity were determined for both semiautomated and conventional measurements. RESULTS: Semiautomated measurements were successful in 124 of the 125 arterial segments. The sensitivity of semiautomated measurements was 89% for all observers; specificity varied between 87% and 89%. For conventional measurements of CE-MRA, sensitivity varied between 79% and 86%; specificity was between 86% and 96%. There was good interobserver agreement between all readers for semiautomated measurements (combined kappa for all 3 observers together = 0.78; ICC = 0.82), as well as for conventional measurements (combined kappa = 0.70; and ICC = 0.83). Differences between ICCs, combined kappa values, and accuracy of both measurements were not significant (all P > 0.05). CONCLUSION: Semiautomated analysis of aortoiliac 3D CE-MRA has the same high accuracy for detection and quantification of stenoses as conventional readings of CE-MRA.     

Noncontrast 3D steady-state free-precession magnetic resonance angiography of the whole chest using nonselective radiofrequency excitation over a large field of view: comparison with single-phase 3D contrast-enhanced magnetic resonance angiography

OBJECTIVES: To evaluate the feasibility of three-dimensional (3D) steady-state free-precession (SSFP) magnetic resonance angiography (MRA) using nonselective radiofrequency excitation in the assessment of cardiac morphology, thoracic aorta, main pulmonary, and proximal coronary arteries. MATERIAL AND METHODS: Thirty consecutive patients (19 males; 11 females; age range, 20-74) with various cardiac and thoracic vascular diseases underwent free-breathing respiratory navigator-gated electrocardiogram-triggered noncontrast SSFP MRA and conventional high-resolution 3D contrast-enhanced MRA (CE-MRA) of the thorax at 1.5 T. Two readers evaluated both datasets for findings, vascular delineation and sharpness (from 0, not visualized to 3, excellent definition), artifacts, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) in 14 vascular segments including aorta, supra-aortic, pulmonary, and coronary arteries, and in cardiac chambers. Statistical analysis was performed using Wilcoxon test for vessel delineation, and [kappa] coefficient for interobserver variability. RESULTS: 3D SSFP and CE-MRA were successfully performed in all patients. Scan time for SSFP MRA ranged from 5 to 10 minutes (mean +/- standard deviation, 7 +/- 2 minutes). On SSFP MRA, readers 1 and 2 graded 233 (97.1%) and 234 (97.5%) coronary arterial segments and cardiac chambers, and 275 (91.7%) and 278 (92.7%) noncoronary arterial segments with diagnostic definition (grades 2 and 3) (k = 0.86). On conventional CE-MRA, readers 1 and 2 graded 10 (4.2%) and 12 (5%) coronary arterial segments and cardiac chambers, and 272 (90.7%) and 270 (90%) noncoronary arterial segments with diagnostic definition (grades 2 and 3) (k = 0.89). Segmental visibility was higher for aortic root, pulmonary trunk, proximal coronary arteries, and heart chambers (P < 0.001), and lower for supra-aortic arteries (P < 0.001) on SSFP MRA for each reader. SNR and CNR values were higher for aortic root and aorta on SSFP MRA (P < 0.001 for both). No significant difference existed between SNR and CNR values for the other vascular segments and cardiac chambers on SSFP and CE-MRA (P > 0.05 for all). The 2 readers demonstrated vascular stenosis and dilatation/aneurysm in 7 and 35 segments on both datasets, respectively. CONCLUSION: Noncontrast 3D SSFP MRA with nonselective radiofrequency excitation provides high image quality and sufficient SNR and CNR for confident assessment of cardiac and thoracic vascular diseases including congenital heart diseases. Our results suggest that noncontrast SSFP MRA outperforms CE-MRA in visualization of cardiac chambers, proximal coronary arteries, pulmonary trunk, and aortic root.     

三维对比增强MR血管成像在头颈部的临床应用

目的:探讨三维对比增强MR血管成像(3DCE-MRA)在头颈部的临床应用价值。材料和方法:应用3D小角度激发快速梯度回波序列,对76例临床疑头颈部血管疾病患者进行3DCE-MRA检查。结果:76例3DCE-MRA均获成功,3DCE-MRA图像明确显示了病变部位及范围。结论:3DCE-MRA快速、准确,有利于头颈部血管疾病的诊断和治疗。