Yoshida Jun, Yamashita Fumio, Sasaki Makoto, Yoshioka Kunihiro, Fujiwara Shunrou, Kobayashi Masakazu, Yoshida Kenji, Kubo Yoshitaka, Ogasawara Kuniaki
Department of Neurosurgery, Iwate Medical University School of Medicine, Morioka, Japan.
Division of Ultrahigh Field MRI, Institute for Biomedical Sciences, Iwate Medical University School of Medicine, Morioka, Japan.
Int J Stroke. 2020 Aug;15(6):657-665. doi: 10.1177/1747493019874732. Epub 2019 Sep 9.
Although patients with improved cognition after carotid endarterectomy usually exhibit postoperative restoration of cerebral blood flow, less than half of patients with such cerebral blood flow change have postoperatively improved cognition. Cerebral small vessel disease on magnetic resonance imaging is associated with irreversible cognitive impairment.
The purpose of the present prospective study was to determine whether pre-existing cerebral small vessel disease affects cognitive improvement after carotid endarterectomy.
Brain MR imaging was performed preoperatively, and the number or grade of each cerebral small vessel disease was determined in 80 patients undergoing carotid endarterectomy for ipsilateral internal carotid artery stenosis (≥70%). The volume of white matter hyperintensities relative to the intracranial volume was also calculated. Brain perfusion single-photon emission computed tomography and neuropsychological testing were performed preoperatively and two months postoperatively. Based on these data, a postoperative increase in cerebral blood flow and postoperative improved cognition, respectively, were determined.
Logistic regression analysis using the sequential backward elimination approach revealed that a postoperative increase in cerebral blood flow (95% confidence interval [CI], 10.74-3730.00; = 0.0004) and the relative volume of white matter hyperintensities (95% CI, 0.01-0.63; = 0.0314) were significantly associated with postoperative improved cognition. Although eight of nine patients with postoperative improved cognition exhibited both a relative volume of white matter hyperintensities <0.65% and a postoperative increase in cerebral blood flow, none of patients with a relative volume of white matter hyperintensities ≥0.65% had postoperative improved cognition regardless of any postoperative change in cerebral blood flow.
Pre-existing cerebral white matter hyperintensities on magnetic resonance imaging adversely affect cognitive improvement after carotid endarterectomy.
尽管颈动脉内膜切除术后认知功能改善的患者通常表现出术后脑血流的恢复，但脑血流发生这种变化的患者中，术后认知功能改善的不到一半。磁共振成像显示的脑小血管疾病与不可逆的认知障碍有关。
本前瞻性研究的目的是确定术前存在的脑小血管疾病是否会影响颈动脉内膜切除术后的认知改善。
对80例因同侧颈内动脉狭窄（≥70%）接受颈动脉内膜切除术的患者进行术前脑部磁共振成像检查，确定每种脑小血管疾病的数量或分级。还计算了相对于颅内体积的白质高信号体积。术前和术后两个月进行脑灌注单光子发射计算机断层扫描和神经心理学测试。基于这些数据，分别确定术后脑血流增加和术后认知改善情况。
采用逐步向后排除法的逻辑回归分析显示，术后脑血流增加（95%置信区间[CI]，10.74 - 3730.00；P = 0.0004）和白质高信号的相对体积（95%CI，0.01 - 0.63；P = 0.0314）与术后认知改善显著相关。尽管术后认知改善的9例患者中有8例表现出白质高信号的相对体积<0.65%且术后脑血流增加，但白质高信号相对体积≥0.65%的患者中，无论术后脑血流有何变化，均无术后认知改善。
磁共振成像显示的术前存在的脑白质高信号对颈动脉内膜切除术后的认知改善有不利影响。
