增强磁共振成像与颈动脉造影在颈动脉狭窄诊断中的应用价值

目的：探讨增强磁共振成像与颈动脉造影在颈动脉狭窄诊断中的应用价值。方法对72例经颈动脉彩超检查疑有颈动脉狭窄的患者采用三维对比增强磁共振血管造影和数字减影血管造影进行检查。结果3D CE-M RA检出颈动脉狭窄112处,DSA检出108处,经统计学分析发现3D CE-M RA检出率（36．84％）与DSA检出率（35．53％）比较无明显差异（x2＝0．11,P ＞0．05）。本文以DSA为诊断颈动脉狭窄的金标准,对3D CEMRA诊断的112处颈动脉狭窄进行敏感性和特异性评估,评估结果显示敏感性为0．81（0．69～0．89）特异性为0．99（0．98～1．00）,ROC曲线下面积为0.95。结论3D CE-M RA诊断颈动脉敏感性和特异性均较高,对颈部动脉狭窄闭塞性病变的显示具有独特的优势。     

颅外颈动脉狭窄支架成形治疗的短期疗效分析

目的　分析颅外颈动脉狭窄支架成形治疗的安全性、有效性和短期疗效。方法　 2 0 0 0年10月至 2 0 0 2年 9月共收治颈动脉狭窄 93例 ,其中颈内动脉颅外分叉部狭窄 86例 ,单纯颅外段狭窄 4例 ,单纯颈总动脉狭窄 2例 ,功能性颈外动脉狭窄 1例 ,采用自膨胀支架进行血管成形治疗。结果　 93例支架植入均获得成功 ,血管狭窄程度从治疗前的平均 (79.5± 14 .6) %降低到 (11.2± 7.8) % ,围手术期无死亡及大卒中发生 ,1例患者出现一过性缺血发作 (TIA) (1.1% ) ,1例患者出现小卒中 (1.1% )。 91例患者获得术后临床随访 ,随访期 3～ 2 5个月 (平均 7.9个月 ) ,随访期间无TIA及卒中发生 ,无死亡。DSA随访 2 9例 ,再狭窄 1例 (3 .4 % )但无临床症状。结论　血管内支架成形术是治疗颈动脉狭窄的安全而有效方法 ,短期效果也令人满意     

血管内支架成形术治疗颅外颈动脉狭窄

目的：观察血管内支架成形术治疗颅外颈动脉狭窄的疗效及其并发症，探讨其安全性与可行性。方法：8例（平均年龄68岁）因颅外颈动脉狭窄〉70％的患者行血管内支架成形术。术前术后行脑血管造影。术中术后给予抗凝治疗。术后每3个月复诊。结果：术后立即行脑血管造影，挟窄血管均开通50％以上。术后3—7个月临床随诊仅1例出现短暂性脑缺血发作（TIA）。本组患者术后30d内主要并发症有：1例患者术后出现轻度抑郁，1例出现TIA，无死亡及卒中发生。结论：血管内支架成形术为颈动脉严重狭窄的患者提供了新的微创治疗手段，但必须严格的掌握适应征与禁忌征。     

颅颈部动脉狭窄的增强 MRA与DSA比较研究

目的 评价椭圆形中心K空间编码增强（CE）MRA在颅颈部动脉狭窄性疾病的诊断价值.方法 48例根据临床症状怀疑有颅颈部动脉狭窄患者接受了CE MRA和DSA检查.MRA图像采用MIP、MPR方法重建,范围包含从主动脉弓部到Willis 环的所有的血管.以DSA为标准,MRA和DSA结果通过统计相关系数比较.结果 以是否狭窄为评判点时,MRA和DSA在各段颅颈部动脉取得较好的一致性.以狭窄程度超过70%为评判点时,MRA和DSA在颈动脉部位取得相当高的一致性.CE MRA显示椎-基底动脉,颈动脉终末段,颅内血管方面稍差.结论 椭圆形中心K空间编码CE MRA能有效地筛选出颅颈部动脉狭窄性病变.在颅外颈动脉部位可使大部分患者免于接受DSA检查.在诊断椎-基底动脉,颈动脉终末段,颅内血管狭窄方面的准确度不够,不能替代传统DSA检查.     

超声造影与DSA诊断颅外段颈动脉狭窄的对比研究

目的:评价超声造影对颅外段颈动脉狭窄的诊断价值.方法:对16例颅外段颈动脉狭窄患者进行超声造影和DSA检查,分别在所获得的图像上测量颈动脉狭窄的直径狭窄率,并对两组数据进行统计分析.结果:本组超声造影共发现颈动脉血管狭窄39处,37处与DSA分级相符合,假阳性2处,其中颈动脉颅外段狭窄的敏感性、特异性、准确度分别为100%,97.8%～99.0%、97.9%～98.5%(K值=0.928～1).结论:超声造影是对颅外段颈动脉狭窄筛查、术前评估、术后随访的最佳检查方法,能基本替代DSA检查.     

经颅彩色多普勒超声与MRA对颅内动脉狭窄的诊断价值比较

目的：比较经颅彩色多普勒超声（TCCD）与MRA对颅内动脉狭窄的诊断准确率。方法：回顾性分析60例（540条颅内动脉）颅内动脉狭窄患者的TCCD与MRA资料,并对比研究。结果：TCCD诊断颅内动脉狭窄148条,诊断敏感度及特异度分别为92.7%和90.1%。MRA诊断颅内动脉狭窄151条。结论：TCCD与MRA均能较准确地反映颅内动脉的狭窄情况,TCCD对诊断颅内动脉狭窄具有较高的敏感性和特异性,有重要的临床价值。     

利用磁共振胰胆管成像对晚期医原性肝外胆管狭窄进行术前评估

目的：探讨磁共振胰胆管成像（MRCP）对晚期医源性肝外胆管狭窄的磁共振胆胰管成像的术前评估价值。方法：对18例MRCP诊断为晚期医源性肝外胆管狭窄并经手术病理证实的患者进行分型及术后手术方式选择，并与手术记录对照分析。结果：18例中能够按照Bismuth分型法进行分型者17例，其中I型3例，Ⅱ型7例，Ⅲ型3例，Ⅳ型3例，1例Ⅱ型狭窄被误分为Ⅲ型，MRCP分型准确16例。根据术前MRCP提供的信息，术中16例采取了正确的手术方法，2例未能采用预期的手术方式。MRCP术前手术方式选择准确16例。结论：MRCP对晚期医源性外胆管狭窄的术前评估有重要价值。     

彩色多普勒超声与对比增强磁共振血管造影对肾动脉狭窄的诊断价值比较

目的 比较彩色多普勒超声(CDUS)和对比增强磁共振血管造影(CE-MRA)在评价肾动脉狭窄(RAS)中的应用价值.资料与方法回顾性分析50例RAS患者共100条肾动脉的CDUS及CE-MRA资料.所有患者最终均经数字减影血管造影(DSA)检查确认诊断.比较CDUS与CE-MRA对RAS检出率的差异.采用受试者工作特征...     

Asymmetry of intracranial internal carotid artery on 3D TOF MR angiography: a sign of unilateral extracranial stenosis

The purpose of this case-control study was to determine whether an asymmetry of size of the intracranial internal carotid artery (ICA) on 3D time-of-flight MR angiography (MRA) is predictive of a high-grade cervical ICA stenosis. Ninety-six stroke/TIA consecutive patients were recruited for the study, of whom 32 had unilateral high-grade ICA stenosis (≥70% NASCET) and were included into the case group, and the remaining 64 did not have such high-grade stenosis and were included in the control group. On intracranial MRA, two observers, blinded to the characteristics of cervical ICA stenosis, independently searched for qualitative size asymmetry between ICAs and measured the cross-sectional surface of the intracranial ICAs. An intracranial size asymmetry was seen in 28 of the 32 high-grade stenoses by both readers, and in 10 (reader₁) and 8 (reader₂) of the 64 controls (sensitivity = 88%, specificity = 84–88%). In patients without agenesia of the A1 segment of the circle of Willis (n = 70), sensitivity was ≥90% and specificity = 96%. Surfaces ratios were significantly different (p < 0.001) between cases and controls. However, using ROC curves analysis, the quantitative processing did not improve the detection when compared with the qualitative assessment of intracranial ICA asymmetry. A size asymmetry of the intracranial ICAs reveals the presence of an underlying high-grade cervical stenosis, with a high degree of confidence, especially in patients without anatomical variant of the anterior part of the circle of Willis. This sign may allow an early detection of high-grade cervical carotid stenosis in stroke patients before dedicated neck imaging is performed.     

MR灌注成像在颈内动脉和大脑中动脉狭窄与闭塞的应用研究

目的 探讨单侧颈内动脉（ICA）／大脑中动脉（MCA）慢性重度狭窄、闭塞患者的MR脑灌注成像（PWI）表现及其应用价值,分析PWI表现与动脉狭窄程度的关系。资料与方法 90例单侧ICA／MCA慢性重度狭窄或闭塞患者行MRPWI检查,计算出有关脑灌注参数图,包括相对脑血流量（rCBF）、相对脑血容量（rCBV）、相对平均通过时间（rMTT）和达峰时间（TTP）图,对PWI表现进行定性和定量分析,并作病变侧与对侧对比。62例单侧ICA重度狭窄或闭塞、28例单侧MCA重度狭窄或闭塞患者分别为重度狭窄和闭塞两组,对脑灌注结果与动脉狭窄程度的关系进行分析。结果 90例ICA／MCA慢性重度狭窄或闭塞患者,PWI均发现灌注异常,表现分为3期：l期3l例,表现为TTP、rMTY延迟,rCBF和rCBV正常;2期41例,表现为TTP、rMTT延迟,rCBF正常．rCBV轻度增高;3期18例,表现为TTP、rMTY延迟,rCBF、rCBV轻度下降。病变区rCBV、rMTY和TTP与对侧比较有显著性差异（P〈0．01）,PWI表现3期之间rCBF无显著差异（P〉0.05）,rCBV、rMTT、TTP均有显著性差异（P〈0．01）。PWI表现分期与ICA／MCA狭窄程度无明显关联性;rMTT、TTP值与ICA／MCA狭窄程度有关联性,闭塞组的rMTT、TTP值高于重度狭窄组（P〈0.01）。结论PWI检查能够显示单侧ICA／MCA慢性重度狭窄或闭塞患者脑血流动力学受损情况,区分局部低灌注的程度,对临床的诊断和治疗具有重要价值,而ICA／MCA狭窄程度不能完全预测脑血流动力学改变。     

Color Doppler, power Doppler and B-flow ultrasound in the assessment of ICA stenosis: Comparison with 64-MD-CT angiography

The purpose of this study is to investigate the diagnostic potential of color-coded Doppler sonography (CCDS), power-Doppler (PD) and B-flow ultrasound in assessing the degree of extracranial internal carotid artery (ICA) stenosis in comparison to CT-angiography (MD-CTA). Thirty-two consecutive patients referred for CTA with 41 ICA-stenoses were included in this prospective study. MD-CTA was performed using a 64 row scanner with a CTDIvol of 13.1 mGy/cm. In CTA, CCDS, PD and B-flow, the degree of stenosis was evaluated by the minimal intrastenotic diameter in comparison to the poststenotic diameter. Two radiologists performed a quantitative evaluation of the stenoses in consensus blinded to the results of ultrasound. These were correlated to CTA, CCDS, PD and B-flow, intraoperative findings and clinical follow-up. Grading of the stenoses in B-flow ultrasound outperformed the other techniques in terms of accuracy with a correlation coefficient to CTA of 0.88, while PD and CCDS measurements yield coefficients of 0.74 and 0.70. Bland-Altman analysis additionally shows a very little bias of the three US methods between 0.5 and 3.2 %. There is excellent correlation (coefficient 0.88, CI 0.77–0.93) with 64-MD-CTA and B-flow ultrasound in terms of accuracy for intrastenotic and poststenotic diameter. Duplex sonography is useful for screening purposes. Clevert D.–A. and Johnson T. contributed equally to this study.     

彩色双功能超声在诊断颈内动脉粥样硬化狭窄中的临床应用

目的:探讨彩色双功能超声在颈内动脉粥样硬化狭窄中的临床应用价值。方法:对58例由于动脉粥样硬化导致颈内动脉狭窄的患者进行二维超声及彩色多普勒血流显像检查,并利用脉冲多普勒对动脉血管狭窄处及狭窄前的血流信号进行测量,同时测量颈总动脉的血流速度。结果:通过测量颈内动脉狭窄处收缩期峰值流速和舒张末期血流速度、颈总动脉收缩期峰值流速和舒张末期血流速度,将二者血流速度相比较并进行分析,同时与彩色多普勒血流显像通过狭窄处血管面积的变化所测的狭窄程度相对照,共检出62支颈内动脉狭窄,其中5支颈内动脉血管腔内血栓形成。二者相结合诊断颈内动脉狭窄的灵敏性和准确性分别为96%和94%。结论:彩色双功能超声在颈内动脉狭窄的诊断中具有重要的临床价值。     

利用灌注MRI技术评价颈内动脉狭窄或闭塞的血流动力学状态

目的 利用灌注磁共振成像(PWI)技术分析颈内动脉狭窄或闭塞时的血流动力学特点。资料与方法 搜集46例单侧颈内动脉狭窄或闭塞患者的资料，借助PWI对其血流动力学特点进行评价。结果 所有患者局部脑血流量没有显著性降低，但大脑中动脉分布区灌注明显延迟，在重度狭窄及闭塞时，分水岭区的灌注也出现障碍；不同的侧支循环代偿仅对大脑中动脉分布区的灌注有所影响，其中前交通动脉作用较为明显。结论 单侧颈内动脉狭窄时，PWI可以准确评价患者的血流动力学状况，而此时的血流动力学障碍与狭窄程度及侧支循环代偿均有明显的关系。     

Magnetic resonance angiography of extracranial carotid and vertebral arteries,including their origins: comparison with digital subtraction angiography

Summary Although carotid bifurcation stenoses are not the only lesions of the extracranial cerebral arteries, magnetic resonance angiographic (MRA) studies to date have concentrated on the carotid bifurcation. We compared digital subtraction angiography of the extracranial portions of the cerebral arteries with MRA using an ordinary body coil, the time-of-flight method, and multiple transverse slabs which covered the arteries down to the aortic arch. Twenty-two patients (15 with arteriosclerotic diseases, 4 with aortitis, and 3 with tumours) had MRA using a 1.5 T magnet system with a three-dimensional fast imaging with steady state precession (FISP) technique. Thirty-nine carotid and 39 vertebral arteries were assessed by three radiologists with regard to stenoses or occlusions, graded as normal, mild (<30%), moderate (30–60%) or severe (>60%) stenosis, or occluded. Grading corresponded well in 81%; stenoses appeared more marked on MRA in 14% and were seen less clearly on MRA in 5%. When 26 carotid bifurcations were assessed separately, grading corresponded well in 95%. MRA is the only method which can display the whole course of the extracranial carotid and vertebral arteries non-invasively and satisfactorily.     

Renal venous thrombosis in an infant with predisposing thrombotic factors: color Doppler ultrasound and MR evaluation

We report a case of a neonate with hereditary thrombophilia presenting with renal venous thrombosis (RVT). Early color Doppler findings of RVT were lacking venous flow, and the arterial diastolic flow was reversed. This very high-resistance arterial flow is for the first time described in neonatal RVT. Magnetic resonance imaging showed low signal intensity of the renal pyramids on T1- and T2-weighted images, suggesting acute hemorrhage. After intravenous contrast injection, persistent cortical enhancement was observed along with lack of medullary enhancement. Despite the progressive reestablishment of some venous drainage, the kidney showed atrophy and loss of function.     

Comparison of digital subtraction angiography with gadolinium-enhanced magnetic resonance angiography in the diagnosis of renal artery stenosis

Renal artery stenosis (RAS) is a treatable cause of hypertension and renal failure for which no ideal screening technique is currently available. We evaluated the use of dynamic gadolinium-enhanced magnetic resonance angiography (MRA) for the diagnosis of RAS. Sixty-two patients with secondary hypertension were enrolled in the study. All patients had conventional renal angiography and gadolinium enhanced MRA. The sequence used was a 3D FMP SPGR sequence with the following parameters (TR: 26 ms, TE: 6.9 ms, flip angle 40 °, field of view 36 × 36 cm, matrix 246 × 256, 1 excitation). Gadolinium 0.3 mmol/kg was administered and 60 1.5-mm-thick partitions were obtained over a duration of 3.5 min. The MRA images were then compared with conventional digital subtraction angiography (DSA) images. Conventional DSA demonstrated 138 renal arteries, whereas gadolinium-enhanced MRA demonstrated 129 (93 %). Twenty-one renal artery stenoses and four occluded arteries were seen at conventional DSA. Gadolinium-enhanced MRA had a sensitivity of 88 %, specificity of 98 %, accuracy of 96 %, positive predictive value of 92 % and negative predictive value of 97 % when compared with conventional DSA. Gadolinium-enhanced MRA is an accurate technique for identifying patients with RAS. It is less sensitive in picking up accessory renal arteries. Received: 17 March 1998; Revision received: 30 June 1998; Accepted: 28 August 1998     

三维增强MR血管成像对冠状动脉桥血管的评价

目的：探讨三维增强MR血管成像（3D CEMRA）评价冠状动脉搭桥术（CABG）桥血管开通状况的临床价值。方法：20例CABG患者共47支桥血管，用3D CEMRA方法进行了研究。MR检查距手术15d至16年。20例患者中14例CABG术后5个月至16年有胸痛症状再发，2例术后临床疑桥血管急性闭塞。对3D CEMRA资料进行评价，确认桥血管开通状况。对7例15支桥血管同时有3D CEMRA和X线血管造影者进行了双盲分析。结果：47支桥血管，3D CEMRA显示通畅25支，闭塞22支，闭塞率为46.8％。7例同时有3D CEMRA和X线血管造影者共15支桥血管，通畅8支，闭塞7支，二者显示完全一致。结论：3D CEMRA对桥血管的评价是可靠和准确的，可作为CABG术后患者一种无创性影像检查方法。     

直接CEMRA在诊断髂静脉阻塞中的价值

目的：评价直接ＣＥＭＲＡ在诊断髂静脉阻塞中的作用。方法：对７例髂静脉阻塞病变患者行增强磁共振血管成像检查,总结直接CEMRA对髂静脉及其侧支的显示结果。结果：CEMRA的原始图像及MIP均清楚显示髂静脉的狭窄,阻塞,7例均清晰显示侧支循环,显示左侧髂静脉全程闭塞4例,部分阻塞2例,狭窄1例。结论：直接增强磁共振血管成像对显示髂静脉阻塞性病变具有较大的临床应用价值。