Analysis of CT perfusion imaging in chronic cerebral circulatory insufficiency and its relationship with crossed cerebellar diaschisis

Objective: To investigate the change of cerebral microcirculation of chronic cerebral circulation insufficiency(CCCI) patients and the relationship between CCCI and crossed cerebellar diaschisis(CCD)by using 320-detector row of low-dose volume CT perfusion imaging. Methods: A total of 158 patients (103 males, 55 females, from 45 to 82 years old, the mean age was 62.9) with symptoms of CCCI were admitted to the First Affiliated Hospital of Wenzhou Medical University from June 2013 to January 2016. Low-dose CTP imaging of whole brain was performed to them using 320-detector row volume CT scanner. The perfusion parameters such as cerebral blood flow(CBF), cerebral blood volume(CBV), mean transit time(MTT), time to peak(TTP) and DLY in both cerebral blood supply areas and cerebellum were got, so were the 4-dimensional CTA images, and rCBF, rCBV, rMTT and rTTP were calculated by ipsilateral/contralateral value. Comparative t-test and independent t-test were applied to analyzing these parameters quantitatively.Chi-square test and Logistic regression model were applied to analyzing the related clinical risk factors. Results: (1) All 108 patients in CCCI group showed asymmetric perfusion within two cerebral hemispheres in CTP images. The CBF, CBV of diseased side were lower than the contralateral mirror area (t(CBF)=-12.89, t(CBV)=-7.031, P(CBF, CBV)<0.001); the MTT of the diseased side was shorter than the contralateral mirror area (t(MTT) =13.310, P(MTT)<0.001); the TTP of the diseased side was longer than the contralateral mirror area (t(TTP)=-4.012, P(TTP)<0.001). The rCBF and rCBV of CCCI group were lower than that in non-CCCI group (t(rCBF)=3.079, t(rCBV)=2.760, P(rCBF, rCBV)<0.01), while the rTTP of CCCI group was longer than that in non-CCCI group (t(rTTP)=4.846, P(rTTP)<0.001). (2)The results of Chi-square test showed that the differences of gender (χ(2)=4.036, P=0.045), hyperlipidemia (χ(2)=7.687, P=0.006), as well as smoking (χ(2)=11.868, P=0.001) had statistical significance between CCCI group and non-CCCI group.Multi-factor Logistic regression analysis showed that hyperlipidemia (OR value=3.736, P=0.016) and smoking (OR value=4.641, P=0.01) were the risk factors of CCCI, while gender had no relationship with it.(3)The incidence of CCD was 18.5% in the CCCI group, and at the same time, the supratentorial corresponding blood supply areas were classified.A total of 10(34.5%) cases were in blood supply area of posterior cerebral artery, 6(20.7%) cases were in blood supply area of middle cerebral artery, 12(41.4%) cases were of anterior cerebral artery, while only 1(3.5%) case was of basal ganglia, in which 4 cases were in blood supply area of posterior cerebral artery, another 4 cases were middle cerebral artery, 7 cases were of anterior cerebral artery and no case of basal ganglia respectively leading CCD alone. Conclusions: CTP could display the microcirculation situation of abnormal brain tissue perfusion area intuitively and quantitatively. Additionally, it could reflect the degree of relationship between cerebral several blood supply areas and cerebellum.