Usefulness Of MRI 3D-SPACE Sequence In Follow-up Of Intracranial Aneurysm Treated By Flow Diverter Device

Objective:To explore the application value of magnetic resonance imaging in the follow-up of intracranial aneurysm treated by flow diverter device with analyzing the correlation between magnetic resonance 3D-SPACE sequence and cerebral angiography.Methods:According to the prospective study method and the inclusion and exclusion criteria of this study,41 patients with intracranial aneurysms treated with flow diverter devices in the Neurointerventional Department of the First Affiliated Hospital of Zhengzhou University from September 2017 to December 2019 were included in the prospective study.Digital subtraction angiography(DSA)and magnetic resonance 3DSPACE sequence(Three-dimensional sampling perfection with application-optimized contrasts by using different flip angle evolutions)were performed during follow-up.Kamran scale was used to evaluate the occlusion degree of aneurysm and the patency degree of parent artery between the two imaging methods respectively.Weighted Kappa test was used to verify the consistency.Calculate the sensitivity and specificity of magnetic resonance 3D-SPACE sequence for evaluating the occlusion degree of aneurysm and patency degree of parent artery while taking DSA as the gold standard.Results:In the evaluation of the degree of aneurysm occlusion by magnetic resonance 3DSPACE sequence and DSA,Kamran classification on DSA is: grade 4 in 18 cases(43.9%),grade 3 in 16 cases(39%),and grade 2 in 7 cases(17.1%).Kamran's classification in 3D-SPACE sequence was: grade 4 in 18 cases(39%),grade 3 in 15 cases(36.6%),grade 2 in 9 cases(22%),and grade 1 in 1 case(2.4%).Their consistency is strong(Kappa value is 0.826).The sensitivity and specificity of 3D-SPACE sequence to evaluate the degree of aneurysm occlusion is 88.9%(16/18)and 92%(23/25).In the assessment of patency of parent artery,DSA showed 38 cases(92.7%)of parent artery patency and 3 cases(7.3%)of parent artery stenosis.Only one patient showed stenosis of the parent in 3D-SPACE sequence and patency on DSA.The consistency between 3D-SPACE and DSA in evaluating the patency of the parent artery was strong(Kappa value was 0.844).The sensitivity and specificity of 3D-SPACE sequence to assess patency of parent artery was 100%(3/3)and 97.4%(37/38).Conclusion:Compared with DSA,the MRI 3D-SPACE sequence can accurately evaluate the occlusion degree of aneurysm and the patency of parent artery after the operation of the flow diverter device.It can be used for the follow-up of patients after the operation of the flow diverter device for the treatment of intracranial aneurysm.