Grading of internal carotid artery stenosis: can CTA overcome the confusion?

PURPOSE: To compare the measurements of internal carotid artery (ICA) stenosis obtained from multidetector computed tomographic angiography (CTA) and digital subtraction angiography (DSA) based on the NASCET and ECST grading methods. METHODS: In a retrospective cohort analysis from data at a tertiary care university clinic, the CTA and DSA images from 69 consecutive patients (52 men; mean age 70.3+/-8.0 years, range 51-85) who underwent both imaging studies within a maximum period of 28 days were interpreted by 2 radiologists blinded to the results of the other modality. The exact degree of ICA stenosis was calculated for both modalities according to NASCET and ECST guidelines. RESULTS: The agreement between both stenosis grading methods was comparable for CTA (R2=0.87) and DSA (R2=0.84); mean differences in stenoses grades between ECST and NASCET were 13.9% (CTA) and 12.9% (DSA, p>0.05). Corresponding results for the intermodality correlation were almost equal for NASCET (R2=0.59) and ECST (R2=0.55), with mean differences of 13.4% and 13.5%, respectively (p>0.05). Sensitivity and specificity of CTA for detecting occlusions was 100% for both modalities and grading systems. For detecting stenoses >70%, the sensitivity and specificity were 90.9% and 54.9%, respectively, for NASCET and 94.7% and 46.3%, respectively, for ECST. For stenoses >50%, the values were 95.8% and 59.6%, respectively, for NASCET and 96.4% and 42.5%, respectively, for ECST. CONCLUSION: The introduction of multidetector CTA cannot overcome the confusion in the exact grading of ICA stenosis because the application of both tested modalities as well as both grading methods results in clinically important differences.     

双源64层CT血管造影在颈内动脉狭窄诊断中的价值

目的评价双源64层CT血管造影（CTA）对颈内动脉狭窄诊断的精确性。方法对41例（82支颈内动脉）有前循环脑缺血症状的患者，使用双源64层CT机进行扫描，运用多平面重建（MPR）、曲面重建（CPR）、最大密度投影（MIP）和容积显示（VR）技术进行重建，轴位像扩大测量血管直径。参照北美症状性颈动脉内膜切除试验标准进行血管狭窄度分级。以DSA为标准，观察CTA检查的灵敏度、特异度、阳性预测值及阴性预测值。结果82支血管中70支CTA和DSA检查结果一致，占85．4％；较DSA诊断结果，CTA诊断狭窄率偏高为10支，占12．2％，偏低为2支，占2．4％。狭窄率〉70％时，CTA的灵敏度为100％，特异度为98．4％，阳性预测值为95％，阴性预测值为100％，与DSA诊断符合率为98．8％；〉50％时，CTA的灵敏度为100％，特异度为96．1％，阳性预测值为93．9％，阴性预测值为100％，与DSA诊断符合率为97．6％。CTA与DSA诊断结果呈正相关（r=0．96，P〈0．01）。由CTA推算DSA的回归方程为Y（DSA）=0．965X（CTA）-1．305。CTA可清晰地显示58支血管有动脉粥样硬化斑块形成。结论双源64层CTA在诊断颈内动脉狭窄程度上与DSA有很高的相关性，可作为颈部血管狭窄筛选的常规检查方法。     

钙化斑块对双源64层CT血管成像诊断颈动脉狭窄的影响

目的评估钙化斑块对双源64层CT血管成像（CTA）诊断颈内动脉（ICA）狭窄的影响。方法筛选93例前循环缺血性脑血管病的患者，同时接受CTA与DSA检查。CTA采用双源64层CT进行扫描，运用多平面重建（MPR）、曲面重建（CPR）、最大密度投影（MIP）和容积显示（VR）技术进行重组和轴位像扩大测量狭窄血管和正常血管的直径。采用北美症状性颈动脉内膜切除试验（NASCET）的方法进行血管狭窄度的分级。根据CT值的大小确定钙化斑块，钙化斑块定义为CT值≥130Hu。CTA和DSA检查结果由两名高年资放射科医师和2名神经内科医师分别进行测量。结果经CTA和DSA检查的186支血管中，ICA狭窄的有117支，其中检测出钙化斑块的有49支，其CT值为130～461Hu；而非钙化斑块致狭窄的ICA有68支。当ICA狭窄率〉50％时，CTA对不伴钙化斑块狭窄血管的诊断敏感度为100％，特异度为94．3％，阳性预测值为94．3％，阴性预测值为100％，Kappa值为0．941；CTA对伴有钙化斑块狭窄血管的诊断敏感度为100％，特异度为87．1％，阳性预测值为82．6％，阴性预测值为100％，Kappa值为0．831。当血管狭窄率〉70％时，不伴钙化斑块CTA的敏感度为100％，特异度为96．0％，阳性预测值为90．0％，阴性预测值为100％，Kappa值为0．928；伴有钙化斑块CTA的敏感度为100％，特异度为92．7％，阳性预测值为72．7％，阴性预测值为100％，Kappa值为0．805。结论64层CTA对非钙化和钙化的ICA狭窄的诊断均具有很高的敏感性，但特异性在诊断钙化斑块时略低。     

CT血管造影对颈动脉粥样硬化性病变的诊断价值

目的 探讨CT血管造影(CTA)诊断颈动脉粥样硬化性病变的价值.方法 对92例前循环缺血发作患者行16层螺旋CTA检查,其中55例于CTA检查前后1周内进行了数字减影血管造影(DSA)检查,64例进行了彩色多普勒超声(CFDS)检查.CTA扫描横断面轴位图像应用三维重建技术作图像后处理,测量颅外段颈内动脉狭窄程度,统计颈动脉粥样硬化斑块,并分别与DSA和CFDS结果比较.结果 CTA与DSA对颅外段颈内动脉狭窄程度分级判断的一致性为90.9％(Kappa=0.87,P＜0.01),CTA对颅外段颈内动脉各级狭窄诊断的灵敏度、特异度、阳性预测值、阴性预测值均较高.CTA与CFDS在颈动脉的斑块检出率差异无统计学意义,两种检查方法共同判断的113处斑块的性质判定的一致性为77.9％(Kappa=0.67,P＜0.01).结论 CTA对颈动脉狭窄程度、粥样硬化斑块诊断有较高的准确性,可作为颈动脉粥样硬化性病变筛选的常规方法.     

Comparison of auscultation, continuous wave Doppler imaging, intravenous digital subtraction angiography and conventional angiography in diagnosis of carotid artery disease

The reliability of auscultation, continuous wave (CW) Doppler imaging, and intravenous digital subtraction angiography (IV DSA) in the assessment of carotid artery disease has been evaluated in comparison with conventional angiography in 30 patients. With auscultation, specificity and sensitivity for internal carotid artery (ICA) stenosis of 50% or more were 81% and 67% respectively. CW Doppler imaging detected ICA stenosis of 50% or more with a sensitivity of 83% and a specificity of 92% and ICA occlusion with a sensitivity of 60%. The specificity of IV DSA was 95% and the sensitivity for ICA stenosis of 50% or more and ICA occlusion were 75% and 100% respectively. Combining CW Doppler and IV DSA findings raised sensitivity for ICA stenosis of 50% or more and ICA occlusion to 89% and 100% respectively and specificity to 95%. The combination of CW Doppler and IV DSA is a safe and accurate test battery in the detection and categorization of carotid disease.     

双源64层CT血管成像在诊断椎动脉狭窄中的价值

目的探讨双源64层CT血管成像（CTA）诊断椎动脉狭窄的准确性。方法58例（116支椎动脉）有后循环脑缺血症状的患者，均同时接受CTA与数字减影血管造影（DSA）检查。采用北美症状性颈动脉内膜切除试验标准进行血管狭窄度的分级，以DSA为标准，评价CTA诊断椎动脉狭窄的准确性。结果与DSA诊断椎动脉狭窄率结果相比，116支椎动脉中，CTA与DSA诊断结果一致的有96支，占82．8％；CTA诊断狭窄率偏高的有17支，占14．6％；CTA诊断狭窄率偏低的有3支，占2．6％。CTA诊断狭窄率≥70％的椎动脉，灵敏度为96．3％，特异度为96．6％，阳性预测值为89．7％，阴性预测值为98．9％，诊断符合率为96．6％。诊断狭窄率≥50％的椎动脉，灵敏度为100％，特异度为91．7％，阳性预测值为88．O％，阴性预测值为100％，诊断符合率为94．8％。CTA与DSA诊断狭窄率的结果呈正相关（r=0．982；P〈0．01）。由CTA推算出的DSA回归方程为Y（DSA）=0．936X（CTA）-1．108。结论CTA在诊断椎动脉狭窄程度上与DSA有很高的相关性，可作为椎动脉狭窄筛选的常规检查。     

分水岭脑梗死的发病机制及Willis环血流代偿对其的影响

目的 探讨分水岭脑梗死（watershed infarction,WSI）的发病机制及Willis环血流代偿对WSI发病机制的影响。方法回顾性分析2005年1月—2007年1月吉林大学第一医院神经内科收治的行脑血管检查（包括颈部血管超声和经颅多普勒超声、磁共振血管成像、CT血管成像、数字减影血管造影等）的前循环脑梗死患者278例,再通过统计学分析脑梗死患者行以上检查的影像学和临床资料。结果WSI（143例）、非WSI大面积脑梗死（66例）、腔隙性脑梗死（69例）3类脑梗死有颈内动脉（internal carotid artery,ICA）或大脑中动脉（middle cerebral artery,MCA）重度狭窄或闭塞者分别为61.5%（88/143例）、53%（35/66例）、7.2%（5/69例）。皮质下上型WSI（48例）、混合型WSI（52例）,ICA和MCA的狭窄多于皮质型WSI（43例）,而有颈动脉斑块的比例与此相反。各类型WSI在ICA、MCA血管狭窄分布上无明显差别,但皮质后型WSI（33例）合并后循环血管狭窄比例高（8例,24.2%）。WSI与非WSI组Willis环血流代偿无差别。各类型WSI Willis环血流代偿亦无差别。结论①WSI最重要的发病机制是ICA或MCA在严重狭窄基础上发生血流动力学变化,低灌注对皮质上下型WSI的影响重于皮质型WSI。②各类型WSI之间ICA、MCA血管狭窄发生率无明显差异,但皮质后型WSI提示ICA或MCA狭窄合并后循环血管狭窄。③相对于血管狭窄,Willis环血流代偿在WSI的发病机制中居次要作用。     

颈动脉超声和CT血管成像及DSA在颈动脉夹层诊断中的应用价值

目的探讨颈动脉超声、CT血管成像(CTA)及DSA对颈动脉夹层的诊断价值。方法对24例颈动脉夹层患者的三种影像资料进行回顾性分析。结果 DSA检查24例,CTA检查16例,颈动脉超声检查21例。DSA、CTA、颈动脉超声检查颈动脉夹层的检出率分别为95.8%(23例)、75.0%(12例)、71.4%(15例)。其中DSA显示以线样征最多见,有12例(占50%),CTA检查和颈动脉超声检查均以双腔征多见,分别为37.5%(6例)和52.4%(11例)。颈动脉超声及CTA检出颈动脉夹层与DSA相比,一致率分别为66.7%和81.3%,差异均无统计学意义(分别为Kappa=0.39,P=0.08;Kappa=0.43,P=0.22)。颈动脉超声联合CTA检查与DSA的一致率为87.5%(15例),(Kappa=0.67,P=0.047),差异有统计学意义。结论 DSA是诊断颈动脉夹层的金标准,不可替代。颈动脉超声联合CTA能提高诊断率,颈动脉超声可作为颈动脉夹层的筛查方法。     

Multimodality Imaging of Carotid Stenosis

Four diagnostic modalities are used to image the following internal carotid artery: digital subtraction angiography (DSA), duplex ultrasound (DUS), computed tomography angiography (CTA), and magnetic resonance angiography (MRA). The aim of this article is to describe the potentials of these techniques and to discuss their advantages and disadvantages. Invasive DSA is still considered the gold standard and is an indivisible part of the carotid stenting procedure. DUS is an inexpensive but operator-dependent tool with limited visibility of the carotid artery course. Conversely, CTA and MRA allow assessment of the carotid artery from the aortic arch to intracranial parts. The disadvantages of CTA are radiation and iodine contrast medium administration. MRA is without radiation but contrast-enhanced MRA is more accurate than noncontrast MRA. The choice of methods depends on the clinical indications and the availability of methods in individual centers. However, the general approach to patient with suspected carotid artery stenosis is to first perform DUS and then other noninvasive methods such as CTA, MRA, or transcranial Doppler US.     

Grading of internal carotid artery stenosis: comparative analysis of different flow velocity criteria and multidetector computed tomographic angiography.

PURPOSE: To evaluate multidetector computed tomographic angiography (CTA) versus published color Doppler sonography (CDS) velocity criteria in the grading of internal carotid artery (ICA) stenosis. METHODS: Sixty-eight consecutive patients (50 men; mean age 70.2 +/- 8.1 years, range 51- 85) with known ICA stenosis and complete CTA and CDS data for 127 carotid arteries were enrolled in this retrospective analysis. The degree of stenosis was determined using CDS velocities according to 5 published sets of criteria, as well as the criteria used at the authors' institution. These outcomes were then correlated using kappa-statistics with the results of multidetector CTA according to NASCET. RESULTS: The best overall agreement was achieved applying the criteria sets of Hwang (kappa = 0.70) and AbuRahma (kappa = 0.68). All 5 occlusions were correctly identified with both modalities. CTA detected 73 ICA stenoses > 70%; the best correlation was with the application of Hwang criteria, which correctly identified 69 (94.5%) > 70% stenoses. In order of increasing tendency to underscore the grade of stenosis, the corresponding results for the other criteria sets were 62 (84.9%) for Mittl, 59 (80.8%) for AbuRahma, 55 (75.3%) each for Nicolaides and Filis, and 50 (68.5%) for Nederkoorn. CTA detected 85 stenoses >50%; the sensitivity of all applied CDS criteria sets exceeded 90%. CONCLUSION: Grading of ICA stenosis > 70% with CDS and CTA results in clinically relevant discrepancies, with higher grades of stenoses assessed by CTA. The choice of CDS grading criteria is of significant clinical importance, especially in the identification of high-grade ICA stenosis.     

磁共振成像对症状性颈动脉狭窄和粥样硬化斑块特征的诊断价值

目的探讨磁共振成像(MRI)对症状性颈动脉狭窄与粥样硬化斑块特征的诊断价值。方法回顾性分析50例症状性颅外段颈动脉粥样硬化性狭窄患者的MRI及数字减影血管造影(DSA)结果。以NASCET标准确定狭窄率和狭窄程度。以DSA为"金标准",检验MRI对颈动脉不同狭窄程度检测的敏感性、特异性、准确性及与DSA检测结果的一致性。计算颈动脉不同狭窄程度中斑块内出血、破裂纤维帽的比率。结果以DSA检测结果为"金标准",MRI检测的敏感性、特异性、准确性如下:轻度狭窄为93.1%、97.5%、90.6%,中度狭窄为84.2%、94.9%、79.1%,重度狭窄为100%、97.5%、97.5%,完全闭塞为100%、100%、100%。MRI和DSA的一致性系数Kappa值为0.863。轻度狭窄、中度狭窄、重度狭窄斑块内出血的比率分别为29.1%、45.0%、52.6%,破裂纤维帽的比率分别为23.6%、40.0%、57.9%。结论 MRI对颈动脉粥样硬化病变有很高的诊断价值.不但能评价颈动脉狭窄程度,而且根据信号特点能分析斑块组成成分,有助于脑血管疾病的早期诊断及早期治疗。     

下肢动脉疾病行64层螺旋CT血管造影的对照研究

目的通过与数字减影血管造影(DSA)的对照,确定64层螺旋CT血管造影(CTA)在诊断下肢动脉病变中的价值。方法选择行下肢动脉64层螺旋CTA及DSA检查的患者24例,DSA与64层螺旋CTA检查间隔时间2周。CT重建采用最大密度投影、容积重建及多平面重建技术。DSA采用步进跟踪造影技术,分段DSA进行下肢血管检查,将64层螺旋CTA与DSA结果进行比较。结果 DSA显示34条共170段下肢动脉,69段血管存在狭窄性病变,CTA诊断血管高估8段,低估8段。以DSA检出血管狭窄程度≥50%为阈值,64层螺旋CTA对下肢动脉狭窄程度诊断的敏感性97.1%,特异性96.0%,准确率97.2%,阳性预测值94.4%,阴性预测值97.9%。结论 64层螺旋CTA是下肢动脉闭塞性病变评估的可靠方法,对下肢动脉硬化闭塞性病变的术前评估、诊断和筛选有较大的帮助,可为制订介入治疗方案提供可靠依据。     

短暂性脑缺血发作患者行CT血管造影与数字减影全脑血管造影的对比研究

目的观察CT血管造影（CTA）与数字减影全脑血管造影（DSA）在评价短暂性脑缺血发作（TIA）患者脑血管状况中的差异。方法对74例TIA患者行CTA及DSA检查,观察两种不同检查方法下患者脑血管异常情况。结果颈内动脉系统TIA中,两种检查方法的敏感性和特异性比较,差异无统计学意义（P〉0.05）;椎基底动脉系统TIA中,DSA检查的敏感性和特异性比CTA高（P〈0.05）;两种方法检查血管狭窄程度效果的比较,DSA优于CTA（P〈0.05）;但CTA检查耗时及并发症发生率低于DSA（分别为P〈0.01和P〈0.05）,且检查费用明显较DSA低。结论 CTA可作为评估颈内动脉系统TIA患者脑血管状况的初筛方法,而椎基底动脉系统TIA患者脑血管状况的评估仍首选DSA。     

颈内动脉起始段狭窄合并其他颅内外动脉狭窄发生频率

目的 分析国人颈内动脉起始部重度狭窄合并其他颅内和(或)颅外动脉狭窄或闭塞的发生率.方法 回顾性总结我院自2001年1月至2008年5月收治的颈动脉重度狭窄患者198例.所有患者均经颈动脉彩色超声和经颅多普勒(TCD)检查,部分患者进行r数字减影血管造影、头颅磁共振血管显像或头领部CT血管成像检杳.结果 在198例颈动脉重度狭窄患者中,86.8%合并其他颅内外动脉狭窄,合并至少一条颅内动脉狭窄者占62.1%,其中以大脑中动脉最多见,26.3%的患者合并串联病变(同侧颈内动脉虹吸段或大脑中动脉狭窄),68.2%的患者合并至少一条颅外其他动脉狭窄,其中以对侧颈内动脉狭窄或闭塞最多见.结论 国人颈内动脉狭窄患者合并串联颅内动脉狭窄或广泛颅内外动脉狭窄的几率较高,此特殊的动脉狭窄分布对颈内动脉内膜剥脱术或支架成型术将造成不可低估的影响.     

Second-Line Myocardial Perfusion Imaging to Detect Obstructive Stenosis: Head-to-Head Comparison of CMR and PET

BackgroundGuidelines recommend verification of myocardial ischemia by selective second-line myocardial perfusion imaging (MPI) following a coronary computed tomography angiography (CTA) with suspected obstructive coronary artery disease (CAD). Head-to-head data on the diagnostic performance of different MPI modalities in this setting are sparse.ObjectivesThe authors sought to compare, head-to-head, the diagnostic performance of selective MPI by 3.0-T cardiac magnetic resonance (CMR) and ⁸²rubidium positron emission tomography (RbPET) in patients with suspected obstructive stenosis at coronary CTA using invasive coronary angiography (ICA) with fractional flow reserve (FFR) as reference.MethodsConsecutive patients (n = 1,732, mean age: 59.1 ± 9.5 years, 57.2% men) referred for coronary CTA with symptoms suggestive of obstructive CAD were included. Patients with suspected stenosis were referred for both CMR and RbPET and subsequently ICA. Obstructive CAD was defined as FFR ≤0.80 or >90% diameter stenosis by visual assessment.ResultsIn total, 445 patients had suspected stenosis on coronary CTA. Of these, 372 patients completed both CMR, RbPET and subsequent ICA with FFR. Hemodynamically obstructive CAD was identified in 164 of 372 (44.1%) patients. Sensitivities for CMR and RbPET were 59% (95% CI: 51%-67%) and 64% (95% CI: 56%-71%); P = 0.21, respectively, and specificities 84% (95% CI: 78%-89%) and 89% (95% CI: 84%-93%]); P = 0.08, respectively. Overall accuracy was higher for RbPET compared with CMR (73% vs 78%; P = 0.03).ConclusionsIn patients with suspected obstructive stenosis at coronary CTA, CMR, and RbPET show similar and moderate sensitivities but high specificities compared with ICA with FFR. This patient group represents a diagnostic challenge with frequent mismatch between advanced MPI tests and invasive measurements. (Danish Study of Non-Invasive Diagnostic Testing in Coronary Artery Disease 2 [Dan-NICAD 2]; NCT03481712)     

有症状颈内动脉狭窄患者血流动力学改变与脑梗死亚型

目的:探讨有症状颈内动脉(ICA)病变患者脑血流动力学变化与脑梗死亚型的关系。方法:113例有症状ICA病变患者行头颅CT平扫、CT灌注成像(CTP)和CT血管造影(CTA)检查。根据CTA结果将患者分为颅外段ICA闭塞组(36例)、重度狭窄组(44例)和轻中度狭窄组(33例)。根据CT平扫结果对患者脑梗死进行分型。根据CTP明确血流动力学状况。分析血流动力学变化与脑梗死亚型的关系。结果:ICA闭塞组(16例)血栓栓塞性脑梗死明显多于重度(2例)或轻中度狭窄组(2例)(P< 0.001)。ICA闭塞组(36例)、重度狭窄组(36例)脑血流灌注降低病例明显多于轻中度狭窄组(9例) (P<0.001)。结论:脑血流灌注降低与ICA狭窄程度密切相关,在脑梗死的发病机制中起着重要作用。对有症状ICA重度狭窄伴有脑血流灌注降低者应给予积极的干预,以避免发生和加重脑梗死。     

CT angiography of stented carotid arteries: comparison with Doppler ultrasonography.

PURPOSE: To determine whether computed tomographic angiography (CTA) is a feasible modality for assessing stented carotid arteries and whether in-stent restenosis based on CTA concurs with ultrasonography (US). METHODS: A retrospective review was conducted of 37 follow-up CTA and US images from 27 patients (23 men; median age 70 years, range 56-77) who received 34 nitinol carotid stents. CTA and US images were compared with respect to assessability and percent stenosis. Both visual estimation (>or=50% or not) and the NASCET method were used to determine percent stenosis in CTA images. For US, a determination of >or=50% stenosis was based on peak systolic velocity (>or=200 cm/s) and an internal carotid artery to common carotid artery ratio >or=2.5. Percent stenosis values by CTA were also compared to values (n=7, 21%) determined by catheter angiography. RESULTS: CTA and US images were "totally assessable" in 27 (73%) and 15 (41%), "totally non-assessable" in 0 (0%) and 3 (8%), and "partially assessable" in 10 (27%) and 19 (51%), respectively. Assessability of CTA images was equal to or better than that of US images in 33 (89%). The percent stenoses by CTA and US were comparable in 20 cases. CTA found >or=50% stenosis using the NASCET method in 4 of 20 stents; none of these showed >or=50% stenosis by visual estimation of CTA or by spectral Doppler US. Compared with catheter angiography, CTA overestimated percent stenosis from 34% to 66% (mean 53%). US confirmed 2 angiographically proven restenoses, but CTA identified only 1. CONCLUSION: CTA provides better image quality for stented carotid arteries than US, but it might be inferior to US in determining restenosis in assessable cases. Therefore, CTA is likely to be an alternative to US in cases of non-assessability. A large-scale study including more restenosis cases is warranted to reveal which modality is more reliable for diagnosis of restenosis.     

64排CT血管成像、磁共振血管成像对头颈部动脉狭窄的诊断价值研究

目的分析64排CT血管成像(CTA)、磁共振血管成像(MRA)对头颈部动脉狭窄的诊断价值。方法收集本院2010年12月—2013年5月收治的经数字减影血管造影(DSA)检查确诊的头颈部动脉狭窄患者59例,并先后行64排CTA、MRA检查。以DSA为金标准,计算64排CTA、MRA及64排CTA与MRA联合诊断头颈部动脉狭窄的敏感度、特异度、阳性预测值、阴性预测值。结果 64排CTA诊断头颈部动脉狭窄的敏感度为97.32%,特异度为98.22%,阳性预测值为93.97%,阴性预测值为99.23%;MRA诊断头颈部动脉狭窄的敏感度为96.23%,特异度为97.38%,阳性预测值为91.07%,阴性预测值为98.94%;64排CTA与MRA联合诊断头颈部动脉狭窄的敏感度为98.10%,特异度为100.00%,阳性预测值为100.00%,阴性预测值为99.47%。结论 64排CTA、MRA对头颈部动脉狭窄有较高的诊断价值,与DSA相比仅对轻度、中度头颈部动脉狭窄的诊断敏感度较低,64排CTA与MRA联合可提高诊断准确性。     

The value of cw-Doppler ultrasonography and DSA in the diagnosis of extra- and intracranial stenosis--a comparison with intraoperative findings

The use of cw-Doppler sonography and digital subtraction angiography (DSA) for diagnosis of cerebro-vascular insufficiency (CVI) was evaluated in a retrospective study. 113 findings obtained by DSA and 315 findings obtained by cw-Doppler sonography were compared to the corresponding intraoperative finding. Furthermore, we examined the incidence of accompanying intracranial stenoses of the carotid artery. The impact of these stenoses on the CVI stage was analyzed by means of 200 transcranial Doppler sonographic studies. Cw-Doppler sonography (sensitivity: 95%) was clearly superior to DSA (sensitivity: 70%) for diagnosis of high grade and subtotal stenoses of the internal carotid artery (ICA). Sensitivity of both methods was insufficient for diagnosis of low grade stenoses (cw-Doppler: 50%, DSA 25%). Analysis of 200 transcranial Doppler sonographic studies did not reveal pathologic changes of intracranial vessels in 67% of all cases. This finding did not depend on the condition of the extracranial vessels and did also not depend on the CVI stage. Additionally, there was no correlation between the incidence and degree of intracranial stenoses and the CVI stage or the degree of stenosis of the ICA. These results support the view that Doppler sonography is the method of choice for diagnosis of high grade stenoses of the carotid artery. The use of DSA is limited to cases in which kinking or occlusion is suspected. Additional intracranial changes did not correlate with the CVI stage.     

How to distinguish between inconsistencies in CTA results and DSA findings

Renovascular hypertension (RVH) is a common cause of secondary hypertension. Noninvasive tests such as computed tomography angiography (CTA) or magnetic resonance angiography have a high specificity and sensitivity for the diagnosis. Digital subtraction angiography (DSA) is, however, the gold standard with which RVH can be reliably diagnosed. We report the case of a 30-year-old Chinese man with right ureter malformation and stenosis of the entire right renal artery. We discuss how to distinguish between inconsistencies in CTA results and DSA findings. Interobserver variability is an important factor that leads to such inconsistencies and cannot be ignored. Importantly, clinicians should combine imaging findings with the patient’s medical history and clinical manifestations rather than blindly believing the DSA results so as to avoid unnecessary medical disputes.