Application Of High-resolution Vessel Wall Magnetic Resonance Imaging In Intracranial Artery Dissection

Purpose:The high-resolution intracranial vessel wall magnetic resonance imaging(HRMR-VWI)can clearly show the structure of the blood vessel wall,and has important value in the diagnosis of intracranial artery dissection(IAD).This study will further analyze the effectiveness and limitations of HR-MR-VWI in diagnosing and evaluating IAD from different clinical symptoms,different treatment options,and prognosis,and propose image classification schemes.Method:Retrospectively analyzed the clinical diagnosis and imaging data of 40 patients with IAD diagnosed and treated in our department of neurosurgery from February 2016 to January 2020.All patients underwent HR-MR-VWI and DSA examinations,followed by endovascular treatment or conservative treatment and followed up with images for at least 4 months.Two imaging physicians performed an independent double-blind evaluation of the HR-MR-VWI image,graded the image quality and diagnosed the signs of intracranial artery dissection,and the results were analyzed by consistency.From the clinical symptom level,the patients were divided into three groups: hemorrhage,ischemia,and non-stroke.From the treatment strategy level,the patients were divided into three groups: unilateral stent placement,stent-assisted coil embolization,and conservative treatment.The situation was divided into three groups: improvement,stability,and exacerbation,and the clinical symptoms and dissection image structure(maximum outer diameter and area,wall thickness,intramural hematoma signal intensity,etc.)were compared between the groups.According to the dissection imaging morphology,the treatment plan was summarized,and the prognostic differences between clinical grouping and imaging classification were compared.Statistical analysis was performed using SPSS 24.0 software.Result:This study finally included 40 patients,male: female = 29:11,the average age of the patients was 53.4(25-75)years,and the main part of the intracranial artery dissection after circulation was mainly(87.8%).Headache(55%)and dizziness(47.5%)were the most common symptoms.42.5% had transient consciousness disturbance,and more than half of the patients had hypertension.Dissection of the tube wall is the most common in dissection imaging signs(92.7%),intimal flaps are the most important(87.8%),a typical "dual cavity sign" can be observed in 68.3%,and intramural hematoma accounts for 61%.The two observers had a good consistency in the interpretation of the IAD image signs.In addition,the signal strength of intramural hematoma was found to be in the acute or subacute phase(56.0%).In the interlayer morphology between the symptom groups,the maximum area of the bleeding group was larger than that of the ischemic group and the non-stroke group.The involvement length of the bleeding group was larger than that of the non-stroke group.The outside diameter ratio of the bleeding group was larger than that of the nonstroke group,and the difference was statistically significant.There was no significant difference in general clinical and prognosis between the symptom groups.Among the treatment groups,the involvement length of SAC group was larger than that of the conservative treatment group,and the difference was statistically significant.There was no significant statistical difference between the remaining measurement indicators.In addition,the improvement rate of endovascular treatment(63.0%)was slightly higher than that of the conservative treatment(53.8%).IAD image classification,atypical type of conservative treatment is given priority to,dilated and expansion type multi-line SAC narrow,wide when involving high surgical risk using conservative treatment,narrow line of SAC or SS,follow-up results showed that the prognosis of narrow type,the highest(75.%),followed by dilated(71.4%),atypical(57.1%),expansion type narrow the lowest(46.7%).Most of the patients had a good prognosis,and the proportion of the improvement group(60%)was higher than that of the stable group(22.5%),plus recombination(17.5%),among which the improvement group was lower than that of the stable group or plus recombination in the maximum area,length of involvement and expansion ratio.Conclusions:1.The most common imaging signs of intracranial arterial dissection were tube wall dilatation with high TOF sequence detection rate.The most important direct sign of the intimal valve,CE-T1 WI shows the best.The SPACE sequence was used to observe the whole structure of the lesion and make quantitative measurement.2.High-resolution vascular imaging is helpful for the assessment of the pathological state of the interlayer lesion,and its imaging morphology can assess the risk of lesion rupture and prognosis.3.Classification based on the image images of high-resolution vascular wall imaging is of certain significance for the selection of treatment strategies.