Application value of SWI signal value in chronic stenosis or occlusive cerebrovascular disease

YAO Weihong; LIU Cong; YAO Huifu; LIANG Changhu

Abstract：Objective To explore the evaluation value of signal value of magnetic sensitivity weighted imaging(SWI)on brain tissue metabolism under chronic stenosis or sub-total occlusion of middle cerebral artery.Methods We performed routine MRI and SWI scans on patients with varying degrees of chronic stenosis or subtotal occlusion of the middle cerebral artery displayed on MRA,applied post-processing software to measure the SWI signal values of the caudate nucleus head,internal capsule,in-sula and temporal cortex in the responsible blood supply area of the affected side,and selected healthy individuals for physical ex-amination as the control group.The analysis of variance was used to determine the inter group differences in the SWI signal val-ues of different levels of MRA anatomical structure blood supply areas.A P-value less than 0.05 indicated a statistically signifi-cant difference.Results Among patients with chronic stenosis or subtotal occlusion of MCA,there were 23 cases of MRA grade Ⅲ,35 cases of MRA grade Ⅱ,and 24 cases ofMRA grade Ⅰ.DWI of the MCA blood supply area did not show high signal in all patients,SWI signal value was obtained in 44 males and 38 females.The highest SWI signal value of MRA level Ⅰ in the tempo-ral cortex area was 98.62±13.94,which was higher than that of level Ⅱ(80.71±8.17)and Ⅲ(87.26±12.76)and the healthy group(30 cases,81.16±21.73).The difference between the groups was statistically significant(F=4.112,P=0.009).There was no statistically significant difference between the caudate nucleus,inner capsule,andinsula groups.In the observation group,curvilin-ear hyperintense vessels were seen in 5 cases of temporal cortex,and thickened draining veins were seenin 8 cases.Conclusion SWI can detect the ischemic state of cerebral tissuein chronic cerebral artery stenosis or occlusion of the blood supply area.It is highly sensitive to MRI prompts with grade Ⅰ stenosis,and can guide clinical diagnosis and treatment.