High-resolution Magnetic Resonance Imaging Pathology And Analysis Of Intracranial Vertebral Artery Dissection Aneurysms

Objective:To investigate the factors of preoperative high-resolution magnetic resonance imaging of intracranial vertebral artery dissecting aneurysms on the prognosis and recurrence of patients after interventional treatment,including intramural hematomas with different signal intensities,thickening and strengthening of aneurysm vessel walls,analyze its application value in the development of interventional treatment strategy.Methods:The clinical data of 19 patients from Kunming Medical University First Affiliated Hospital diagnosed as IVADA by HR MRI or DSA from September 2017 to November 2019 and underwent interventional treatment were retrospectively analyzed.All patients underwent HRMRI Three-dimensional fast spin echo Cube plain and enhancement scan,three-dimensional time of flight magnetic resonance angiography scan,2D-FSE-T2WI scan and CE-MRA sequence scan.Two experienced imaging diagnostic doctors evaluated the image pathological information such as the signal strength of the intramural hematomas,thickening and strengthening of aneurysm vessel walls,double-cavity sign and intimal flap.All patients were followed up by imaging and telephone.The recurrence of the patients was recorded and the efficacy and prognosis of the patients were evaluated by the modified Rankin scale score.One-way analysis of variance and Fisher's exact probability method were used for statistical analysis to examine the effects of different imaging pathological features on prognosis and recurrence in patients.The difference was statistically significant with P<0.05.Results:This study included 19 patients diagnosed with DSA or HRMRI for IVADA and concurrent interventional therapy,a total of 19 dissection aneurysms.A total of 19 cases(100%)of intramural hematomas were detected by HRMRI,5 cases(26.3%)of dissection flaps,10 cases(52.6%)of double-cavity sign,and 16 cases(84.2%)of aneurysm-like expansion.The 3D-FSE-Cube T1WI sequence was used to quantify the signal intensity of intramural hematomas in all patients.The isointens signal was similar to those of adjacent muscles.The intramural hematomas were divided into 4 groups,6 cases(31.6%)in the homogeneous isointense signal group,4 cases(21.2%)in the homogeneous hyperintense signal group,7 cases(36.9%)in the heterogeneous iso-hyperintense signal group and 2 cases(10.6%)in the heterogeneous iso-hyporintense signal groupin the promiscuous-low signal group.There were no statistically significant differences in baseline data of patients in each T1WI signal group,such as age,gender,aneurysm length and width,clinical symptoms,and risk factors(P>0.05).There was a statistically significant difference in the improvement rate between the four groups(P=0.02),and a statistically significant difference in the exacerbation rate(P=0.014).There was a statistically significant difference in the prognosis between the iso-hyperintense signal group and the iso-hyoerintense signal group(P=0.028).All patients were judged by the 3D-FSE-Cube T1WI enhanced scan for the presence or absence of IVADA vascular wall thickening and enhancement.A total of 16 patients(84.2%)with aneurysm wall thickening and enhancement were observed in 19 patients,of which 14 patients(73.7%)were mildly enhanced,2 patients(10.5%)were significantly enhanced,and 3 patients(15.8%)were not thickened and enhanced.The comparison of the improvement rates and exacerbation rates of the three groups of patients showed that there was no statistically significant difference in the improvement rates of the three groups of patients(P>0.05),and the difference between the exacerbation rates was statistically significant(P=0.025).Comparison of exacerbation rates between the three groups showed that there was a statistically significant difference between patients in the mildly intensive group and those in the significantly intensive group(P=0.025).Conclusion:1.? AD A patients preperative HRMRI with different 3D-FSE-Cube T1WI signal intensities intramural hematomas in the preoperative have statistically significant differences in prognosis,intramural hematomas with heterogeneous iso-hyperintense signal group was higher than that in the heterogeneous iso-hypointense signal group.HRMRI signal intensity of intramural hematoma is one of the relevant factors affecting its prognosis.2.The preoperative HRMRI aneurysm vessel wall was thickened or not with 3D-FSE-Cube T1WI enhanced scan and the patients with different degrees of enhancement had statistically significant differences in prognosis.Patients with significantly thickened and strengthened aneurysm vessels wall have a higher rate of disease progression than patients with mildly strengthened ones.Thickening and strengthening of aneurysm vessel wall is one of the relevant factors affecting its prognosis.3.HRMRI has great value in the diagnosis of ?ADA and the evaluation of imaging pathology,and it can be used for preoperative evaluation and non-invasive follow-up observation of patients.It can also be used to guide the development of interventional treatment plans.