Kimura Kazuto, Akamatsu Yosuke, Fujimoto Kentaro, Uwano Ikuko, Sasaki Makoto, Fujiwara Shunrou, Kobayashi Masakazu, Koji Takahiro, Yoshida Kenji, Terasaki Kazunori, Ogasawara Kuniaki
From the Department of Neurosurgery (K.K., Y.A., K.F., M.K., T.K., K.Y. K.O.), Iwate Medical University, Yahaba, Japan.
Division of Ultrahigh Field MRI, Institute for Biomedical Sciences (I.U., M.S.), Iwate Medical University, Yahaba, Japan.
AJNR Am J Neuroradiol. 2025 Aug 1;46(8):1579-1586. doi: 10.3174/ajnr.A8692.
Post-carotid endarterectomy (CEA) cerebral hyperperfusion (CH) can cause intracerebral hemorrhage and cognitive decline. Alterations in susceptibility in response to acetazolamide (ACZ) on 7T MRI quantitative susceptibility mapping (QSM) detect elevated CBV occurring due to impaired cerebrovascular autoregulation. We explored preoperative relative susceptibility changes on 7T MRI QSM in response to ACZ and their ability to predict CH following CEA.
Sixty-three patients with uni- or bilateral cervical ICA stenosis of ≥70% underwent 7T MRI at baseline and at 5, 10, 15, and 20 minutes after ACZ administration before surgery. The difference between the susceptibility of venous structures and surrounding brain parenchyma at each time point after ACZ administration relative to the difference at baseline (relative susceptibility difference [RSD]) on QSM images was calculated in the cerebral hemisphere ipsilateral to the surgery site. Brain perfusion SPECT was conducted preoperatively and immediately following CEA to detect postoperative CH (≥100% rise in CBF postoperatively).
In 9 patients with postoperative CH, the RSD was significantly increased at 5 or 10 minutes following ACZ administration ( < .05) but was reduced at 15 and 20 minutes ( < .05). In 54 patients without postoperative CH, the SD at all 4 time points after ACZ administration was significantly lower than the baseline value ( < .05). The area under the receiver operating characteristic curve to predict postoperative CH was significantly greater in RSD (0.981; 95% CI, 0.910-0.999) than in RSD (0.872; 95% CI, 0.764-0.943) ( < .05) or RSD (0.780; 95% CI, 0.658-0.874) ( < .01). Sensitivity, specificity, and positive and negative predictive values for RSD at a cutoff near the left upper corner of the curve were 100%, 89%, 60%, and 100%, respectively. Logistic regression analysis revealed that only RSD significantly predicted postoperative CH (95% CI, 455.9-4043.6; < .05).
Changes in susceptibility on preoperative 7T MRI QSM following ACZ administration predict CH following CEA. Patients with increased RSD on pre-CEA 7T MRI QSM following ACZ administration should undergo brain perfusion imaging immediately after surgery. Detection of CH on postoperative brain perfusion imaging warrants intensive blood pressure control.
颈动脉内膜切除术（CEA）后脑血流过度灌注（CH）可导致脑出血和认知功能下降。7T磁共振成像定量磁化率图谱（QSM）显示，乙酰唑胺（ACZ）作用下的磁化率变化可检测出因脑血管自动调节功能受损而导致的脑血容量升高。我们探讨了术前7T MRI QSM上ACZ作用后的相对磁化率变化及其预测CEA术后CH的能力。
63例单侧或双侧颈内动脉狭窄≥70%的患者在手术前行基线7T MRI检查，并于术前给予ACZ后5、10、15和20分钟进行检查。在QSM图像上，计算给药后各时间点手术侧大脑半球静脉结构与周围脑实质磁化率的差异相对于基线差异（相对磁化率差异[RSD]）。术前及CEA术后立即进行脑灌注SPECT检查，以检测术后CH（术后脑血流量升高≥100%）。
9例术后发生CH的患者，ACZ给药后5或10分钟RSD显著升高（<.05），但在15和20分钟时降低（<.05）。54例未发生术后CH的患者，ACZ给药后所有4个时间点的RSD均显著低于基线值（<.05）。预测术后CH的受试者操作特征曲线下面积，RSD（0.981；95%CI，0.910 - 0.999）显著大于RSD（0.872；95%CI，0.764 - 0.943）（<.05）或RSD（0.780；95%CI，0.658 - 0.874）（<.01）。曲线左上角附近临界值处RSD的敏感性、特异性、阳性和阴性预测值分别为100%、89%、60%和100%。Logistic回归分析显示，只有RSD能显著预测术后CH（95%CI，455.9 - 4043.6；<.05）。
术前7T MRI QSM上ACZ给药后的磁化率变化可预测CEA术后的CH。CEA术前7T MRI QSM上ACZ给药后RSD升高的患者术后应立即进行脑灌注成像。术后脑灌注成像检测到CH需要严格控制血压。
