Dynamic Contrast-Enhanced Magnetic Resonance Imaging Analysis for Prognosis of Intracranial Dissecting Aneurysm With Intramural Hematoma After Endovascular Treatment

Inclusion Criteria: adult patients (age 18-80 years) patients' ability to cooperate during the MRI examination; patients who are were diagnosed with IDA according to DSA and MRI; expectation of adequate patient safety during these examinations; unequivocal evidence by MRI (IMH\>5 mm on the perpendicular plane to the long axis of the vessel) of IDA; IDA treated by the endovascular approach; patients' willingness to participate in the study. Exclusion Criteria: patients with pre-existing diagnoses of arteritis, fibromuscular dysplasia, iatrogenic aneurysms or pseudoaneurysms; extracranial dissecting aneurysms extended into the intracranial segment; patients with other diseases or poor general condition with expected survival of less than 2 year; the IDA has already been treated by the endovascular treatment; patients lacking DCE-MRI follow up.