Spontaneous recanalization of responsible vessels on MRA in infarction of internal carotid artery system

ZHANG Ying; CHEN Zhen; WANG Xinli; WANG Xinyu; ZHANG Jing

doi:10.19300/j.2017.L5405zt

Abstract：Objective To investigate spontaneous recanalization rate, course, infarct pattern, and recanalization mechanism of responsible artery in patients with acute stroke. Methods We conducted a retrospective review of 441 pa-tients (male/female, 279/162;age 31-90 years, mean age 63.17±10.10 years) with acute stroke in the territory of the internal carotid artery (ICA) system from May 2015 to May 2016 in Tianjin Medical University General Hospital. All patients with cerebral infarction undergo routine MRI, DWI and MRA examinations.According to the MRA showed whether there is any stenosis or not in the infarct responsibility vessel, the whole patients are divided into recanalization group and non recanaliza-tion group. The differences in age and time interval from the onset to the MRA examination were compared with the two sam-ple t test between the 2 groups, and the patient's gender, lesion side, and other clinical data were compared with chi square test. Results There were 300 of 441 patients (68.03%, male 192 and female 108) with responsible arterial stenosis or occlu-sion, which were classified into recanalization group, whereas 141 patients (31.97%, male 87 and female 54) without respon-sible arterial stenosis or occlusion were classified into non recanalization group. The rate of spontaneous recanalization was 31.97%. There was no significant difference between the two groups in terms of age, sex, lesion side, and other clinical data (all P>0.05). The time interval from onset to MRA in the recanalization group was significantly shorter than that in the non-recanalization group (P=0.002). Most patients of both groups had single infarction, and the most common pattern was perforat-ing artery infarction. The recanalization ratio within 3 days was 90.07%in the recanalization group, and within 3-7 days the recanalization ratio was 9.93%. Conclusion The incidence of early spontaneous recanalization is about 30%. Spontaneous recanalization usually occurs approximately within the first 3 days. The recanalization rate is 90.07%. The spontaneous re-canalization of small terminal arteries is high. Understanding the spontaneous recanalization after cerebral infarction may help clinicians to avoid aggressive treatment.