酰胺质子转移加权成像评估慢性缺血性脑组织酸碱代谢水平

Amide proton transfer weighted imaging in assessment of acid-base metabolism in chronic ischemic brain tissue

目的采用MRI酰胺质子转移加权(APTw)成像探讨慢性缺血性脑血管病(CICVD)患者脑组织酸碱代谢的改变。方法该研究为横断面研究。回顾性分析2021年1月至2022年7月于四川大学华西医院就诊的39例CICVD患者。所有患者均接受CT灌注(CTP)成像和APTw成像。采用NeuBrainCARE脑灌注分析软件,分析脑灌注受损的部位,并测量平均通过时间(MTT)、达峰时间(TTP),将CTP与APTw图像进行标准空间匹配,测量相同部位的APTw值。为了与正常组织进行比较,测量同侧大脑半球、对侧大脑半球、同侧小脑半球灌注未受损区域的正常表现白质(NAWM)的APTw值。采用单因素重复测量方差分析比较灌注受损脑组织、同侧大脑NAWM、对侧大脑NAWM、同侧小脑NAWM APTw值差异,使用Bonferroni法进行多重比较的校正。采用Pearson相关系数分析灌注受损脑组织的APTw值与MTT、TTP的相关性。结果39例CICVD患者中,灌注受损脑组织APTw平均值和最小值均显著低于同侧大脑半球、对侧大脑半球、同侧小脑半球灌注未受损区域NAWM(P<0.001)。病变同侧的小脑半球灌注未受损区域NAWM的APTw平均值和最小值均显著高于同侧大脑半球、对侧大脑半球灌注未受损区域NAWM(P<0.001)。相关性分析显示灌注受损脑组织MTT值与APTw平均值、APTw最小值呈显著的负相关(r值分别为-0.90、-0.82,P均<0.001);TTP值与APTw平均值、APTw最小值呈显著的负相关(r值分别为-0.86、-0.78,P均<0.001)。结论APTw值可以反映CICVD患者灌注受损脑组织存在的酸中毒。

Objective To explore changes of acid-base metabolism in the brain tissue of patients with chronic ischemic cerebrovascular disease(CICVD)using MRI amide proton transfer-weighted(APTw)imaging.Methods This was a cross-sectional study.From January 2021 to July 2022,thirty-nine patients with CICVD at West China Hospital,Sichuan University were retrospectively included.All patients received CT perfusion(CTP)and APTw imaging.NeuBrainCARE brain perfusion software was used to analyze the impaired perfusion sites and measure the mean transit time(MTT)and time to peak(TTP).Standard spatial matching between CTP and APTw images was performed to measure the APTw values of the same sites.For comparison with normal tissue,APTw values were measured for normal-appearing white matter(NAWM)in the ipsilateral cerebral hemisphere,the contralateral cerebral hemisphere,and the ipsilateral cerebellar hemisphere in areas of impaired perfusion.ANOVA was used to compare the APTw values of impaired perfusion brain tissue,ipsilateral cerebral NAWM,contralateral cerebral NAWM,and ipsilateral cerebellar NAWM.The Bonferroni method was used to correct for multiple comparisons.Pearson correlation coefficient was used to analyze the correlation between APTw values and MTT and TTP in the cerebral tissue with impaired perfusion.Results In 39 patients with CICVD,both the mean and minimum APTw values of cerebral tissue with impaired perfusion were significantly lower than those in the NAWM of the ipsilateral cerebral hemisphere,the contralateral cerebral hemisphere,and the ipsilateral cerebellar hemisphere(P<0.001).In the NAWM of the cerebellar hemispheres with unimpaired perfusion,both the mean and minimum APTw values were significantly higher than those in the ipsilateral cerebral hemispheres and the contralateral cerebral hemisphere(P<0.001).Correlation analysis showed that MTT was significantly negatively correlated with both the mean APTw and the minimum APTw(r values were-0.90 and-0.82,P<0.001).TTP was significantly negatively correlated with both the mean APTw and the minimum APTw(r values were-0.86 and-0.78,P<0.001).ConclusionAPTw value can reflect acidosis in cerebral tissue with impaired perfusion in patients with CICVD.