颈动脉阻断脑耐受性评估

Assessment of the brain tolerance to unilateral carotid artery occlusion: A technical note

目的 建立一综合评价单侧颈动脉阻断脑耐受性的方法。方法 颈动脉临时或永久阻断前 ,常规行临时球囊阻断试验 (TBO)。在临床神经系统功能评价的同时还进行单光子发射计算机断层扫描 (SPECT)脑显像、脑血管数字减影造影 (DSA)及经颅多普勒 (TCD)和颈动脉残端压 (SP)监测。结果 DSA显示所有 11例受试者Willis环沟通均良好。仅 1例未通过TBO ,其SPECT相对对称指数 (rS)为 74.5 % ,SP为 6 .8kPa(1kPa =7.5mmHg) (5 5 .0 % )。其余都通过了 45minTBO ,rS为 (97.8± 3.8) % (91.2 %～ 10 2 .5 % ) (P =0 .0 0 2 ) ;SP为(8.6± 1.7)kPa (4 .4～ 11kPa) ,相对SP为 (72 .3± 11.3) % ;同侧大脑中动脉 (MCA)血流速度下降率为 (16 .3±6 .9) %。阻断颈总动脉 (CCA) 3例 ,测得颈内动脉 (ICA)血流方向逆转 ,系统血压升高。 1例因置管引起ICA闭塞。结论 本耐受性试验较合理、实用 。

Objective Attempt to establish an objective criterion for assessing the brain tolerability to carotid artery occlusion. Methods The endovascular trial of balloon occlusion of carotid artery (TBO) in combination with single photon emission computed tomography (SPECT), digital subtracted angiography (DSA), transcranial Doppler ultrasonography (TCD) and carotid artery stump pressure (SP) measurement as well as clinical neurological examination were performed routinely for those patients who might have carotid artery manipulated or permanently occluded. Results Out of the 11 cases, one failed the TBO, though an adequate collateral circulation was observed angiographically. The patient's SP and relative symmetry index (rS) of SPECT imaging were 6.8 kPa and 74.5% respectively. All the remaining cases passed the 45 min TBO. In the asymptomatic group, after carotid artery occlusions, the mean velocity of ipsilateral middle cerebral artery fell (16.3±6.9)%, and the rS was (97.8±3.8)% (91.2%～102.5%, P=0.002). The SP was (8.6±1.7) kPa [(72.3±11.3%) of the baseline, range (4.4～11) kPa]. For each item, the ICA was occluded spontaneously during the test. A reversal internal carotid artery (ICA) flow was noted in 3 patients with balloon inflated in the common carotid artery (CCA). When the CCA was occluded, the systematic blood pressure and heart rate increased apparently, while this phenomenon did not occur when the balloon was inflated in the ICA. Conclusion With this TBO technique, silent areas of decreased perfusion might be detected clinically. We suggest it be a routine examination prior to carotid manipulations.