Diagnostic Value Of HR-MRI And DCE-MRI In Unilateral Middle Cerebral Artery Inflammatory Stenosis

Objective:（1）Exploring the role of 3.0T High-Resolution Magnetic Resonance Imaging（HR-MRI）in unilateral middle cerebral artery inflammatory stenosis-occlusion;（2）To explore the value of 3.0T Dynamic Contrast-Enhanced Magnetic Resonance Imaging（DCE-MRI）in vascular permeability parameters of unilateral middle cerebral artery inflammatory stenosis-occlusion and/or ischemic stroke.Methods:The research contains 36 cases who are diagnosed as unilateral middle cerebral artery M1 stenosis in our hospital from January 2018 to January2019,and the neurology department combined with various data to suspect central nervous system vasculitis but could not be diagnosed.These 36 cases are scanned with 3.0T HR-MRI and DCE-MRI.（1）According to the changes of the wall and lumen structure,combined with clinical data to make an etiological diagnosis of stenosis,and assess the degree of vascular stenosis;（2）Quantitative calculation of permeability parameters at the distal end of the stenosis（the middle cerebral artery supply area）using the DCE-MRI Tool software to assess the integrity of the blood-brain barrier;（3）After 6 months,review and select the same area of interest to compare the changes of various parameters.Results:Among the 36 patients who met the inclusion criteria,combining with HR-MRI and clinical data comprehensively diagnosed central nervous system vasculitis in 23 cases,atherosclerosis in 10 cases,smoke syndrome in 3cases.The mean age of 36 patients is 40.2 years old（range,16-68 years old）and the median age is 39 years old.The average age of 23 patients with central nervous system vasculitis was37.7 years old,and the ratio of male to female was 16:7.Fifteen patients（65.2%）had a history of smoking;16 patients（70.0%）were positive for cytomegalovirus and/or herpes simplex virus Ig G.Two patients（8.7%）were positive for autoimmune antibodies（β-2 glycoprotein antibody,anticardiolipin antibody,etc）,and one of them（4.3%）was diagnosed with Behcet syndrome.Ten patients（43.5%）were in the acute-subacute phase of cerebral infarction,3 patients（13.0%）were in the chronic phase of cerebral infarction,and 10 patients（43.5%）had no cerebrovascular events.Central nervous system vasculitis HR-MRI show thickening of the wall and enhancement of stenosis with lumen.Among them,5 cases（21.7%）have focal lesions,10 cases（43.5%）have segmental lesions,and 8 cases（34.8%）have full-length lesions.Eight patients（34.8%）have luminal occlusion,13（56.5%）have moderate to severe stenosis,and only 2（8.7%）have mild stenosis.Four cases（17.4%）of inflammatory lesions involved both the internal carotid artery and the contralateral middle cerebral artery,causing thickening and strengthening of the wall,but the lumen is not significantly narrow.The relationship between the extent and extent of vascular stenosis and cerebral infarction is analyzed.The results are not statistically significant（P=0.253）.In the acute-subacute phase of cerebral infarction,10 patients（100%）had significant damage to the blood-brain barrier in the target area,and the K^transvalue（0.098±0.038）was significantly higher than the mirror side（0.003±0.001）and was statistically significant;Ten patients were reviewed in the month,and the K^trans value（0.039±0.014）was reduced in the same region of interest.In the chronic phase of cerebral infarction,3 patients（100%）had a K^trans value（0.044±0.012）higher than that of the mirror side.Two patients were reviewed after 6 months,and the K^trans value（0.018±0.009）was reduced in the same region of interest.The K^trans value（0.007±0.001）in the 10patients（100%）without cerebrovascular events was not statistically significant compared with the mirror side;After 6 months,4 patients were reviewed.The K^trans value（0.006±0.001）was not significantly changed in the same region of interest.The 2 patients（12.5%）have a significantly higher K^trans value（0.066±0.019）in the other region of interest than the mirror side（0.007±0.001）.Conclusion:1.HR-MRI has a unique display effect on the changes of intracranial arterial wall and lumen structure,and has a higher value in the cause of diagnosis;2.There is no significant correlation between the extent and extent of cerebral artery stenosis caused by central nervous system vasculitis and the occurrence of acute cerebrovascular events;3.DCE-MRI can quantitatively reflect the damage of blood-brain barrier in the lesion area of ischemic stroke,and can effectively guide clinical treatment and evaluate prognosis.At the same time,it can predict the occurrence of acute cerebrovascular events to some extent.