比较锁骨下动脉盗血椎动脉颅内、外段频谱形态和血流动力学参数的差异，探讨其与临床症状的相关性。

连续纳入2014年8月至2015年5月在首都医科大学宣武医院经血管超声检查并经CT血管成像（CTA）或数字减影血管造影（DSA）确诊为锁骨下动脉中度（50%~69%）及以上狭窄或闭塞性病变患者213例，经彩色多普勒血流成像（CDFI）和经颅多普勒（TCD）或经颅彩色多普勒（TCCD）检测并记录椎动脉颅外段（V2段）和颅内段（V4段）的血流频谱形态，按照锁骨下动脉盗血程度经典3期分型（Ⅰ期隐匿型、Ⅱ期部分型和Ⅲ期完全型）对颅内外椎动脉血流频谱进行比较，并对相同盗血程度的颅内、外段椎动脉（VA）的收缩期峰值流速（PSV）和舒张末期流速（EDV）测值进行比较。

213例锁骨下动脉中度以上狭窄或闭塞病变患者中颅内、外段椎动脉盗血程度相同者190例（89.2%，190/213），其中Ⅰ期盗血者52例（27.4%，52/190），Ⅱ期盗血者82例（43.2%，82/190），Ⅲ期盗血者56例（29.5%，56/190）。（2）进一步分析盗血程度相同的190例患者椎动脉颅内外段血流速度的差异性发现，无论Ⅱ期盗血者或Ⅲ期盗血者颅内段PSV和EDV测值均大于颅外段（P均<0.05），Ⅱ期盗血颅内段PSV和EDV测值均明显大于颅外段[PSV：（-44.0±23.1） cm/s vs （-32.9±21.1） cm/s，P=0.000；EDV：（20.1±10.9） cm/s vs （15.4±10.3） cm/s，P=0.005]；Ⅲ期盗血颅内段PSV和EDV大于颅外段[PSV：（-81.7±30.0） cm/s vs （-68.2±47.6） cm/s，P=0.035；EDV：（-13.9±11.1）cm/s vs （-9.4±7.0） cm/s，P=0.05]，而Ⅰ期盗血者颅内段和颅外段的流速测值并无明显差异[ PSV：（51.7±14.7） cm/s vs （49.9±14.3） cm/s，P=0.445；EDV：（22.4±7.2 ）cm/s vs （19.8±6.1） cm/s，P=0.660 ]。（3）无论颅内段或颅外段，Ⅱ型盗血患者临床症状的发生率（颅内段30.2%，29/96，颅外段30.8，28/91）均高于Ⅰ型和Ⅲ型盗血患者，但差异无统计学意义（颅内段χ²=1.106，P=0.575；颅外段χ²=1.106，P=0.602）。颅内外盗血程度不一致患者临床症状的发生率高于颅内外盗血程度一致的患者[39.1%，9/23>25.8%，49/190）。

锁骨下动脉狭窄或闭塞时，椎动脉血流频谱反映的颅内外段盗血程度基本一致，但在Ⅱ期和Ⅲ期盗血时颅内盗血程度明显高于颅外。Ⅱ期盗血患者临床症状的发生率相对高于Ⅰ期和Ⅲ期盗血患者。

To compare the difference of waveform between intracranial and extracranialsegment of vertebral artery as well as hemodynamic parameters in patientswith subclavian steal syndrome and explore its relativity with clinical symptoms.

Between May 2015 and August 2014, 213 patients with moderate (50%-69%) orsevere stenosis or occlusive lesions detected by vascular ultrasound and CTA or DSA imaging were enrolled in this study. The blood flow waveform examined by color duplex flow imaging (CDFI) and transcranial Doppler (TCD) or transcranial color coded Doppler (TCCD) in extracranialand intracranial artery segment were comparisoned. According to the classical stages (stageⅠ: occult steal; stageⅡ: partial steal; stage Ⅲ: complete steal), the hemodymics paremeter such as peak systolic velocity (PSV) and end diastolic velocity (EDV) of intracranial and extracranial artery were analyzed and compared in patients with same degree of steal syndrome.

Among those 213 patients, there were 190 cases (89.2%, 190/213) with same degree of steal in intracranial and extracranial VA segments, including 52 cases (27.4%, 52/190) of phaseⅠsteal, 82 cases (43.2%, 82/190) of phaseⅡsteal and 56 cases (29.5%, 56/190) of phase Ⅲ steal. The analysis of the differences of blood velocities between the intracranial and extracranial VA in 190 patients with same stages of steal demonstrated that in patients with phaseⅡand phase Ⅲ steal, the PSVs and EDVs of intracranial segment were greater than those of the extracranial segment (P<0.05). There was no significant difference in patients with phaseⅠsteal (P>0.05). The incidence of clinical symptom was relatively higher in patients with phaseⅡstealthan those in patients with phaseⅠand Ⅲ steal with no statistical difference (P>0.05) in intracranial or extracranial segment. Among those patients with inconsistent degree of steal, the incidence of relevant symptom rates inhanced (39.1%>25.8%).

When there is stenosis of subclavian artery, the blood spectrum of VA reflects a relatively same degree of steal of both intracranial and extracranial VA. However, the blood velocity is obviously higher in intracranial VA comparing to extracranial VA in patients with phaseⅡand phase Ⅲ steal. The incidence of clinical symptom was relatively higher in patients with phaseⅡsteal than those in patients with phaseⅠand Ⅲ steal.