Association between the fetal-type posterior cerebral artery and intracranial anterior and posterior circulating atherosclerotic plaques using multi-contrast magnetic resonance vessel wall imaging

Background: Intracranial atherosclerotic disease (ICAD) is one of the most common causes of ischemic stroke. The fetal-type posterior cerebral artery (FTP) affects intracranial collateral circulation, which is closely related to the occurrence and development of ICAD. Knowledge of the relationship between FTP and ICAD is important for developing treatment strategies for FTP patients diagnosed with atherosclerotic diseases. This study aims to quantitatively analyze the association between the FTP and intracranial atherosclerotic plaques using magnetic resonance vessel wall imaging (VW-MRI).Methods: This retrospective study enrolled patients with recent cerebrovascular symptoms (stroke or transient ischemic attack <2 weeks) who were diagnosed with atherosclerotic plaque(s) by VW-MRI in one hospital from October 2018 to March 2022. They were classified into the FTP group and the non-FTP group. Plaque characteristics and vascular-related parameters in intracranial arteries were compared between the two groups. Univariate and multivariate logistic regressions were performed to determine the odds ratios (ORs) and corresponding 95% confidence intervals (CIs) of the plaque characteristics between the two groups.Results: A total of 104 patients (mean age: 61.8 +/- 9.8 years, 57 males) were included for VW-MRI scan analysis. 40 (38.46%) and 64 (61.54%) were classified into the FTP and the non-FTP groups, respectively. The plaques of middle cerebral artery (MCA) in the FTP group were more likely to occur on the dorsal and superior walls of the lumen compared with the non-FTP group (37.50% vs. 17.19%, P=0.001). The remodeling index (RI) of MCA was statistically different between the two groups (1.071 +/- 0.267 vs. 0.886 +/- 0.235, P=0.007). No significant differences were found in vertebrobasilar artery (VBA) plaque distributions (17.50% vs. 9.38%, 10.00% vs. 12.50%, 20.00% vs. 17.19%, P>0.05) and characteristics between the two groups (RI: 1.095 +/- 0.355 vs. 0.978 +/- 0.251; eccentricity index: 0.539 +/- 1.622 vs. 0.550 +/- 0.171, P>0.05).Conclusions: The plaques in the FTP group were more likely to occur on the dorsal and superior walls of the MCA, and the presentence of FTP was found to be significantly correlated with vascular remodeling of MCA atherosclerotic plaques. The relationship between the severity of intracranial atherosclerosis and the presence of FTP can provide valuable information for clinicians to intervene early and prevent the occurrence of stroke.