The Value Of CT Perfusion Imaging In Treatment Of Moyamoya Disease Treated By Combined Revascularization

Objective:To investigate the value of CT perfusion imaging(CTP)in the treatment of moyamoya disease combined with revascularization.Methods:The data of 8 cases of patients who were diagnosed with moyamoya disease by whole brain digital subtraction angiography(DSA)were analyzed retrospectively.All patients were treated by STA-MCA anastomosis combined with encepho-duro-myo-synangiosis(STA-MCA + EDMS).Before and two weeks after operation,the head CTP was examined.Using the Philips 256-slice spiral CT,the brain pressure was 120kv and the flow rate was 150 mAs.The scanning layer thickness and coverage were 5mm and 12 x 12cm respectively,and the scanning time was 50s.Iodoproamide was chosen as a contrast media.It was injected into the human body through the elbow vein at a rate of 5 ml/s by using a high-pressure syringe.The total dose was 50 ml.The first scan gives 300-400 original images,and we conveyed them into the post-processing device.The brain perfusion software was used for analysis and process.Select the basilar artery and the superior sagittal sinus to determine the arterial input function and the vein output function.The perfusion parameter image about cerebral blood flow(CBF),cerebral blood volume(CBV),mean transit time(MTT)and time to peak(TTP)were obtained by using the deconvolution model.Observe the pseudo-map which shows the ischemic tissue of the brain carefully,and mark the abnormal perfusion area of the most extensive aspects of the ischemic tissue.The CBF,CBV,MTT,and TTP values are measured on both sides by mirriring.Calculate the ratio on both sides we can get the relative CBF(rCBF),relative CBV(rCBV),relative MTT(rMTT),and relative TTP(rTTP).All data were collected and analyzed using SPSS 19.0 statistical software.The rCBV,rCBF,rMTT and rTTP values of the blood supply area corresponding to the preoperative and two weeks after the operation were matched by t test.P<0.05 for the difference was statistically significant.Results:Preoperative surgical side showed varying degrees of low perfusion compared to the opposite side obviously in all of the 8 patients treated by STA-MCA ＋EDMS.The cerebral blood perfusion was improved after the surgical treatment.It showed that the rCBF,rCBV were increased compared with preoperative,the rMTT shorter than before surgery.The difference was statistically significant(P<0.05).There was no significant difference in rTTP between the two groups before and after operation(P<0.05).Conclusion:CT perfusion imaging can accurately show the area and extent of cerebral ischemia in patients with moyamoya.It provide an objective basis for the surgeon to accurately understand the disease,select the surgical indications and surgical methods.CT perfusion imaging has important significance in assessing the prognosis and improvement of blood perfusion in postoperative brain tissue in patients with moyamoya combined with revascularization.Postoperative CTA showed bypass grafts without stenosis,occlusion,and blood flow unobstructed.