目的:一些接受血管重建术的烟雾病(MMD)成年患者术后认知功能改善或下降。缺血性MMD的血运重建手术可增加脑血流量(CBF)并改善脑氧代谢。然而,大脑过度灌注,这是短期的,同侧CBF的主要增加远远大于大脑的代谢需求,有时作为并发症发生。大脑过度灌注产生广泛的,同侧白质和皮质区域的损伤最小。本前瞻性研究的目的是确定动脉旁路手术引起的CBF变化如何影响有症状的缺血性MMD和痛苦灌注的成年患者的认知功能。
方法:32例脑疾患灌注患者,根据15O气体正电子发射断层扫描确定,行单个颞浅动脉-大脑中动脉(中央前区M4)吻合术。术前进行脑灌注单光子发射计算机断层扫描(SPECT)研究,在术后第一天,手术后2个月。手术前和手术后2个月也进行了神经心理学测试。
结果:术后神经心理学评估显示10例(31%)认知改善,8例(25%)无变化,下降14例(44%)。根据脑灌注SPECT和症状,10例患者被认为患有脑高灌注综合征,所有这些患者都表现出术后认知能力下降。术后第1天的相对中央前CBF在术后认知功能下降的患者(167.3%±15.3%)明显高于改善的患者(105.3%±18.2%;p<0.0001)或未改变的患者(131.4%±32.1%;p=0.0029)认知功能。术后2个月相对中央前CBF与术前相比,术后认知改善的患者(17.2%±3.8%)明显大于术后无改变的患者(10.1%±2.4%;p=0.0003)或术后认知下降的患者(11.5%±3.2%;p=0.0009)。
结论:动脉搭桥手术后急性期脑过度灌注会损害认知功能。在没有急性期脑过度灌注的慢性阶段,CBF的增加可以改善有症状的缺血性MMD和痛苦灌注的成年患者的认知功能。
Some adult patients with moyamoya disease (MMD) undergoing revascularization surgery show an improvement or decline in cognition postoperatively. Revascularization surgery for ischemic MMD augments cerebral blood flow (CBF) and improves cerebral oxygen metabolism. However, cerebral hyperperfusion, which is a short-term, major increase in ipsilateral CBF that is much greater than the metabolic needs of the brain, sometimes occurs as a complication. Cerebral hyperperfusion produces widespread, minimal injury to the ipsilateral white matter and cortical regions. The aim of the present prospective study was to determine how changes in CBF due to arterial bypass surgery affect cognitive function in adult patients with symptomatic ischemic MMD and misery perfusion.
Thirty-two patients with cerebral misery perfusion, as determined on the basis of 15O gas positron emission tomography, underwent single superficial temporal artery-middle cerebral artery (M4 in the precentral region) anastomosis. Brain perfusion single-photon emission computed tomography (SPECT) studies were performed preoperatively, on the 1st postoperative day, and 2 months after surgery. Neuropsychological tests were also performed preoperatively and 2 months after surgery.
Postoperative neuropsychological assessments demonstrated cognitive improvement in 10 cases (31%), no change in 8 cases (25%), and decline in 14 cases (44%). Based on brain perfusion SPECT and symptoms, 10 patients were considered to have cerebral hyperperfusion syndrome, and all of these patients exhibited a postoperative decline in cognition. Relative precentral CBF on the 1st postoperative day was significantly greater in patients with postoperative cognitive decline (167.3% ± 15.3%) than in those with improved (105.3% ± 18.2%; p < 0.0001) or unchanged (131.4% ± 32.1%; p = 0.0029) cognition. The difference between relative precentral CBF 2 months after surgery and that before surgery was significantly greater in patients with postoperative cognitive improvement (17.2% ± 3.8%) than in those with no postoperative change (10.1% ± 2.4%; p = 0.0003) or with postoperative decline (11.5% ± 3.2%; p = 0.0009) in cognition.
Cerebral hyperperfusion in the acute stage after arterial bypass surgery impairs cognitive function. An increase in CBF in the chronic stage without acute-stage cerebral hyperperfusion improves cognitive function in adult patients with symptomatic ischemic MMD and misery perfusion.