16层螺旋CT在下肢动脉闭塞性疾病中的应用价值

目的:探讨16层螺旋CT血管成像术在诊断下肢动脉闭塞性疾病中的应用价值。方法:对42例临床疑为外周动脉闭塞性疾病的患者行下肢动脉16层螺旋CT血管造影(CTA),扫描范围从肾动脉水平达足底。薄层重建横断面图像传入HP xw8000工作站,进行血管三维重建。所有患者于CTA检查前或后2周内行数字减影血管造影(DSA)。以DSA为金标准,评价CTA诊断的准确性。结果:在882个动脉节段中,870个节段在CTA与DSA均可以显示,在DSA图像上,狭窄闭塞的节段共260个(轻度狭窄32段,中度狭窄24段,重度狭窄44段,闭塞160段),最大密度投影(MIP)显示中度以上狭窄的敏感性、特异性及准确性分别为99.1%、99.7%、99.5%。结论:16层螺旋CT在评估下肢动脉闭塞性疾病方面与常规血管造影结果无明显差别,是下肢动脉闭塞性疾病理想的影像学检查手段,可部分替代DSA检查。     

糖尿病下肢动脉狭窄与Wagner分级及踝肱指数的相关性

目的探讨糖尿病下肢动脉狭窄程度与糖尿病足Wagner分级、踝肱指数的相关性及临床意义。方法对49例疑有糖尿病下肢动脉疾病患者,行下肢动脉CE-MRA扫描。经最大信号强度投影重建获得下肢整体血管图像,并结合原始图像综合分析血管狭窄情况,记录血管狭窄评分。同时采集患者临床资料,记录Wagner分级及踝肱指数。分析血管狭窄程度与临Wagner分级及踝肱指数的相关性。结果糖尿病下肢动脉狭窄评分与Wagner分级呈正相关(r=0.791,P0.01),与踝肱指数呈负相关(r=-0.871,P0.01)。结论下肢动脉CE-MRA能较为客观、全面的反映糖尿病患者下肢动脉狭窄情况,为临床诊治及预防糖尿病足提供了有价值的信息。     

16层螺旋CT血管造影对下肢动脉闭塞性疾病的诊断及其临床价值简

目的：探讨16层螺旋CT血管造影对下肢动脉狭窄及闭塞性病变的临床应用价值。方法对20例下肢动脉闭塞性疾病患者行16层螺旋CT血管造影（CTA）,CTA重建采用最大密度投影（MIP）、容积再现技术（VR）、多平面重组（MPR）及曲面重建（CPR）。将下肢血管分成8段,每段血管的狭窄程度分为：正常、轻度狭窄、中度狭窄、重度狭窄、闭塞5个级别。结果20例患者共显示狭窄段72个,其中髂总动脉狭窄5段,髂外动脉狭窄8段,股动脉狭窄10段,动脉狭窄22段,胫前动脉狭窄11段,胫后动脉狭窄12段,腓动脉狭窄4段。结论16层螺旋CT是下肢动脉狭窄及闭塞性病变的可靠评估方法。     

多层螺旋CT血管造影在糖尿病下肢动脉病变中的诊断价值

目的 探讨多层螺旋CT血管造影(MSCTA)在诊断糖尿病下肢动脉病变中的诊断价值.方法 对46例糖尿病下肢血管病变患者的92条下肢进行MSCTA检查,所有血管分为552个节段,重点对股浅动脉、腘动脉、胫前动脉、胫后动脉、腓动脉、足背动脉进行分析,46例中9例与血管造影对照,14例与手术对照,25例与超声检查对照研究.结果 MSCTA与血管造影符合率91.26%,与手术符合率92.13%,与超声符合率93.09%.结论 MSCTA能准确直观地显示下肢动脉的立体解剖特点,清楚显示下肢动脉狭窄、闭塞,为糖尿病下肢动脉病变的诊断和治疗提供重要依据,是糖尿病下肢动脉病变较为理想的检查方法.     

MRI和MRA对烟雾病的诊断价值

目的：评价ＭＲＩ和ＭＲ血管成像（ＭＲＡ）在烟雾病中的诊断价值。材料与方法：回顾性分析２３例烟雾病患者的ＭＲＩ和ＭＲＡ资料，ＭＲＡ采用三维时间飞跃法。结果：２３例患者ＭＲＡ图像均有不同程度的颈内动脉分叉处的血管狭窄／闭塞，１８例基底节区异常网状的血管和１４例软脑膜侧支循环血管显示清晰。ＭＲＩ上显示了所有患者的脑实质改变和１５例颈内动脉分叉处的血管狭窄／闭塞改变，所有患者根据其ＭＲ上脑血管的改变均可做出正确的诊断。结论：ＭＲＡ结合ＭＲＩ能对烟雾病患者做出正确的诊断和较准确的分期，同时可用于烟雾病患者的随访检查和术后复查。     

64层螺旋CT血管成像对下肢动脉系统疾病的应用价值

目的:探讨64层螺旋CT血管成像术在下肢动脉疾病中的应用价值及技术优势。方法:对21例疑有下肢动脉疾病患者行64层螺旋CT增强扫描,扫描范围从肾动脉水平达足底。薄层重建横断面图像传入Wizard工作站,进行血管三维重建。其中21例结合常规血管造影评价64层螺旋CT血管成像术(CTA)的准确性。结果:在441个动脉节段中,435个节段在CTA与DSA均可以显示,在DSA图像上,狭窄闭塞的节段共130个(轻度狭窄16段,中度狭窄12段,重度狭窄22段,闭塞80段),最大密度投影(MIP)显示中度以上狭窄的敏感性、特异性及准确性分别为:99.1%、99.7%、99.5%。结论:64层CT血管成像是一种高度准确、非侵袭性的成像技术,在评估下肢动脉疾病方面与常规血管造影结果无明显差别,是下肢动脉疾病较好的影像学检查手段。     

双向内膜下成形术在股浅动脉长段闭塞介入治疗中的应用

目的探讨双向内膜下成形术(SIA)在股浅动脉长段闭塞介入治疗中的临床价值。资料与方法采用股腘动脉双向内膜成形术治疗11例长段股浅动脉闭塞患者,术后复查踝肱指数并随访12个月。结果 11例患者股浅动脉闭塞段均开通,技术成功率100%,下肢缺血症状改善,复查踝肱指数0.74±0.26,与术前0.34±0.13比较明显升高(t=3.35,P<0.05);术后3个月、6个月和12个月支架通畅率分别为100%、90.9%和72.7%。结论股腘动脉双向内膜下成形术治疗长段股浅动脉闭塞成功率高,近期疗效确切,为介入治疗复杂下肢动脉硬化闭塞提供了新思路。     

2型糖尿病双下肢动脉病变MSCTA诊断及危险因素分析

目的研究2型糖尿病患者双下肢动脉病变MSCTA影像表现,并探讨影响双下肢动脉病变的主要危险因素。方法 61例患者行双下肢动脉MSCTA检查,运用MPR、MIP、VR等后处理分析动脉硬化斑块的分布情况及各节段狭窄程度等。详细记录患者年龄、病史、踝臂指数、生化指标（总胆固醇（TC）,甘油三酯（TG）,高密度脂蛋白（HDL-C）,低密度脂蛋白（LDL-C））。运用Logistic回归分析双下肢动脉狭窄及踝臂指数的主要危险因素。结果 61例均扫描成功,共1281段血管：327段有硬化斑块;28段轻度狭窄,21段中度狭窄,10段重度狭窄,14段闭塞。硬化斑块主要好发于上段（腘动脉以上）,Х^2=115.371,P〈0.001;狭窄多发生在下段（腘动脉及其以下）,Х^2=13.523,P〈0.001。下肢动脉狭窄危险因素有年龄、病史和TC异常,TC异常是独立危险因素（OR=7.860,95%CI：1.988-31.077）;踝臂指数异常危险因素为动脉狭窄和TC异常,动脉狭窄是独立危险因素（OR=28.310,95%CI：5.411-148.121）。结论 MSCTA可以清楚、准确判断2型糖尿病双下肢血管的病变。对于踝臂指数异常或者TC升高的糖尿病患者,更容易伴有双下肢动脉的狭窄,建议对此类患者有必要进行临床干预和进一步行MSCTA检查。     

非增强MRA对下肢动脉硬化闭塞症膝下动脉的评价:与增强MRA和DSA作对照

目的探讨非增强磁共振血管造影(MRA)评价下肢动脉硬化闭塞症膝下动脉病变通畅性及累及程度和范围的应用价值。方法连续性入组45例跛行患者,行静息踝肱指数测量,其中21例患者ABI小于0.9,进一步行非增强MRA、增强MRA和数字减影血管造影(DSA)检查,共计27条下肢,以DSA作为标准,重点对腘动脉、胫腓干、胫前动脉、胫后动脉、腓动脉,共135个节段进行分析。结果共观察135个动脉节段。非增强MRA显示99通畅,增强MRA显示96通畅,DSA显示101通畅。非增强MRA与增强MRA、DSA比较观察血管通畅性一致性良好(Kappa0.85,P0.001)。对于狭窄≥50%动脉的判断无明显统计学差异(P0.05)。三种检查均存在的狭窄程度≥50%的血管节段共计15个。非增强MRA与增强MRA、DSA比较,对狭窄长度的测量存在明显统计学差异(P0.05)。结论非增强MRA在观察血管通畅性、识别血管有无狭窄方面与增强MRA及DSA基本等同,显示血管受累范围较增强MRA准确,是诊断下肢血管病变的一种可靠方法,但对血管狭窄程度有过度评估的倾向。当患者存在肾功能不全时,非增强MRA可以替代DSA和增强MRA,成为此类患者术前血管评估的可靠手段。     

老年人下肢闭塞性动脉硬化症早期诊断的探讨（附104例分析）

本文采用无创伤性彩色及脉冲多普勒超声,四肢血压测定以及血液流变学检测对104例老年人下肢血流动力学、上臂和踝部节段动脉压、踝肱指数以及血液流变学指标进行了分析,并探讨老年人下肢闭塞性动脉硬化症的早期诊断。     

移床-血管示踪MR血管成像在下肢动脉疾病中的临床应用

目的研究移床-血管示踪MRA在下肢动脉疾病中的应用价值,探讨移床技术的优势。方法对36例临床疑有下肢动脉疾病的患者行移床-血管示踪三维动态增强MRA检查,其中急性下肢动脉闭塞症5例,检查后行急诊手术,慢性下肢动脉闭塞31例,其中10例行DSA检查。15例可评价病例以DSA或手术结果作为金标准进行效果评价。结果36例病人均满意地显示了完整的下肢动脉血管。将每条下肢分为14个血管节段观察,15例可评价病例共观察420段血管节段,显示可比动脉节段102段。与DSA或手术结果比较,两者诊断符合率为93.14%(95/102),MRA诊断的敏感度为100%,特异度为100%。5例急性下肢动脉闭塞症与手术结果比较,MRA对血管闭塞长度的评价与手术无统计学差异(t=2.251,P>0.05)。结论移床-血管示踪MRA与DSA或手术比较,具有很好的一致性,能全面、准确地评价下肢动脉病变,是一种可靠的、无创的、有应用价值的检查方法。     

64层螺旋CT对下肢动脉疾病的诊断及其临床价值

目的 探讨64层螺旋CT对下肢动脉狭窄闭塞性疾病的诊断价值. 资料与方法 对40例下肢动脉闭塞性疾病患者行64层CT容积扫描,15例1周内同时行数字减影血管造影（DSA）.将下肢血管分成8段,每段血管的狭窄程度被分为：正常、轻度狭窄、中度狭窄、重度狭窄、闭塞5个级别.将DSA与CTA结果进行比较. 结果 共对198个动脉段进行研究,对其狭窄程度显示一致的有191个,被CTA高估6个,低估1个.一致性检验Kappa值为0.953,P=0.017＜0.05,两者分析结果的一致性较好. 结论 64层螺旋CTA是下肢动脉狭窄硬化性疾病的可靠评估方法.     

下肢静脉MRA的评价

目的：探讨MRA在诊断下肢深静脉狭窄和血栓形成的应用价值。材料和方法：25例临床诊断为下肢深静脉血栓形成患者，进行2DTOF法MRA检查，其中3例同时行动态增强MRA（DCEMRA）。检查范围包括下腔静脉下段至小腿静脉。25例中的18例同时行彩超检查。结果：25例MRA共显示静脉以上（包括静脉）深静脉225条，其中正常静脉76条，血栓形成32条，轻度狭窄（1－49％）50条，明显狭窄（50－99％）45条，闭塞（10％）22条。18例MRA与彩超对照可比静脉162条，彩超示正常静脉53条，异常静脉109条，二者显示一致152条，符合率为93．82％（152／162）。结论：MRA对显示下腔静脉狭窄和血栓形成的部位、范围和程序准确性较高，为临床正确诊断和治疗后随访提供了新的无损伤检查手段。     

透视触发并行采集高分辨率三维增强颈动脉磁共振血管成像术

目的评估透视触发和并行采集技术用于高分辨率三维增强颈动脉磁共振血管成像术(3DCEMRA)的可行性。方法80个临床诊断或怀疑颈动脉狭窄的病人接受3DCEMRA检查。使用透视触发软件触发启动颈动脉3DCEMRA扫描,同时采用K空间椭圆形中心填充法和加速因子为2的并行采集技术。对显示的各段动脉和有无静脉早期显影做分析。动脉狭窄分成动脉管壁不规则、轻度狭窄、严重狭窄和闭塞。颈动脉3DCEMRA的显示结果与其他检查结果做了对照。结果所有病例均顺利触发和完成颈动脉3DCEMRA检查。3DCEMRA显示了80例病人总共800支动脉段(100%显示率),所有病例在动脉显示区域内静脉均未显影或显影很淡,对诊断不构成影响。结果显示有680段动脉正常、41段动脉管壁不规则、24段动脉轻度狭窄、51段严重狭窄和4段闭塞。另外10段颈动脉狭窄处溃疡形成,12例患者除见颈动脉狭窄以外,还发现合并椎动脉和/或锁骨下动脉狭窄。36例病例,与其他血管成像技术作了比较,3DCEMRA的检查结果与之完全符合,未出现高估或低估血管狭窄程度。结论透视触发并行采集高分辨率3DCEMRA简单可行,成像时间短,空间分辨率高,能清楚显示颈动脉,它将在颈动脉狭窄的诊断中起重要作用。     

Contrast-enhanced 3D MRA with centric ordering in k space: A preliminary clinical experience in imaging the abdominal aorta and renal and peripheral arterial vasculature

The objective of this study was to determine the clinical utility of a contrast-enhanced, centric reordered, three-dimensional (3D) MR angiography (MRA) pulse sequence in imaging the abdominal aorta and renal and peripheral lower extremity arteries. Twenty-eight MRA studies were performed on 23 patients and four volunteers at 1.5 T using a 3D contrast-enhanced, centric reordered pulse sequence. In 20 patients, the abdominal aorta and renal arteries were imaged, and in seven patients, the lower extremity arteries were imaged. In 19 patients, a total of 51 renal vessels were evaluated (33 renal arteries using .1 mmol/kg of gadopentetate dimeglumine and 18 renal arteries using .2 mmol/kg of gadoteridol). A total of 70 peripheral arterial segments were assessed using .2 mmol/kg of gadoteridol. Correlation with conventional angiography was made for the following 14 cases: renal artery stenosis (four cases), abdominal aortic stenosis (one case), arteriovenous fistula in a transplant kidney (one case), renal arteriovenous malformation (one case), common iliac artery aneurysms (one case), and peripheral lower extremity (six cases). Of the 70 peripheral arterial segments evaluated, in 35, there was correlation with x-ray angiography. The mean percent of aortic signal enhancement was significantly higher in the .2 mmol/kg dose group (370.8 ± 190.3) than in the .1 mmol/kg dose group (184.5 ± 128.9) (P = .02). However, there was no apparent difference between the two doses for visualization of the renal and accessory renal arteries. There was concordance between the contrast-enhanced 3D MRA studies and conventional angiography in all cases of renal artery and peripheral arterial stenoses and occlusions, including visualization of reconstituted peripheral arterial segments. There was no evidence of spin dephasing effects at sites of stenoses on the 3D contrast-enhanced MRA studies. Contrast-enhanced, centric reordered, 3D MRA can rapidly image the abdominal aorta and renal and accessory renal arteries, as well as peripheral lower extremity arteries, with high resolution. Accurate depiction of the vascular lumen at sites of stenosis is made because of the lack of spin dephasing effects, even with hemody-namically significant stenoses. Additional larger clinical trials are required with this promising technique.     

Accuracy of pre- and postcontrast 3D time-of-flight MR angiography in patients with acute ischemic stroke: correlation with catheter angiography

BACKGROUND AND PURPOSE: 3D time-of-flight (TOF) MR angiography (MRA) is insensitive to slow flow; however, the use of MR imaging contrast agents helps to visualize slow-flow vessels and avoids overestimation of vascular occlusion. The purpose of this study was to correlate pre- and postcontrast 3D TOF MRA with the results of conventional angiography during endovascular reperfusion therapy and to determine the accuracy of postcontrast 3D TOF MRA. MATERIALS AND METHODS: Thirteen patients who underwent endovascular reperfusion therapy for acute ischemic stroke were retrospectively analyzed. MR imaging techniques included single-slab 3D TOF MRA with and without contrast, as well as perfusion-weighted imaging. Angiography during reperfusion therapy was used as a standard of reference. Affected arteries were divided into segments either proximal or distal to the lesion, and pre- and postcontrast MRA signals were graded as absent, diminished or narrowed, or normal. RESULTS: In 2 of 5 patients with arterial stenosis and 6 of 8 patients with complete occlusion, MRA signal intensity proximal to each lesion was absent, indicating a proximal pseudo-occlusion on precontrast MRA. Postcontrast MRA demonstrated an arterial signal intensity proximal to the stenotic or occlusive lesions in all 13 patients. Arterial signal intensity distal to the occlusion was identified on postcontrast MRA in 7 of 8 patients having complete occlusion, and the extent of occlusion on postcontrast MRA was similar to results of conventional angiography. CONCLUSION: In this small series, postcontrast 3D TOF MRA more accurately delineated the extent of stenotic or occlusive arterial lesions than precontrast MRA.     

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。     

Contrast-enhanced subtraction MR angiography in occlusive disease of the pelvic and lower limb arteries: results of a prospective intraindividual comparative study with digital subtraction angiography in 76 patients.

PURPOSE: The purpose of this work was to evaluate the feasibility and clinical use of MR angiography (MRA) for examining the pelvic and lower limb arteries in patients with arterial occlusive disease. METHOD: Seventy-six patients with clinical signs of peripheral arterial occlusive disease were included in the study. MRA was performed using a fast contrast-enhanced high-resolution 3D technique that covered the area from the distal abdominal aorta to the distal lower limbs in two examination steps. RESULTS: In all patients, diagnostic images comparable with those of conventional intraarterial digital subtraction angiography (DSA) could be obtained. No false-negative findings were seen in the iliac, femoral, or popliteal arteries. Ten to 16% of the mild stenoses and 6-14% of the severe stenoses, mainly in the crural vessels, were overgraded compared with intraarterial DSA. Particularly in patients with proximal severe obstructions or occlusions, the crural segments could be depicted more clearly due to decreased arterial runoff in conventional angiography. CONCLUSION: The consistency of the excellent depiction of the vascular territories of the distal aorta and the pelvic and lower limb arteries in a standardized setting suggests great potential for the use of MRA in the primary diagnosis of peripheral arterial occlusive disease.