Increased Tortuosity Of Bilateral Distal Internal Carotid Artery Is Associated With White Matter Hyperintensity

Background:Although the pathophysiological mechanism of brain white matter hyperintensity is unclear,with the development of artificial intelligence in Neuroradiology we can recently explore the possible relationship with white matter hyperintensity by using quantitative parameter.Objective:To demonstrate the relationship between bilateral distal internal carotid arterial tortuosity and white matter hyperintensity volume in elderly individuals.Methods:345 patients(age>65years)with brain MR examinations were retrospectively included(mean age,72.1±6.25 years;55.9% ≥70 years;44.1% male;vertigo 44.6%).Three radiologists with different experience in Neuroradiology(3 years,7 years,15 years respectively)independently scored white matter hyperintensity using Fazekas scale.Kendall’w test was used to compare the consistency of their scoring results.The correlation between white matter hyperintensity volume and Fazekas scale scoring results was analyzed with Spearman’ correlation.Tortuosity index of bilateral distal internal carotid artery and basilar artery on MRA,and white matter hyperintensity volume on T2-Flair were measured.The association of tortuosity index with quantitatively derived brain white matter hyperintensity volume,after adjusting for demographics,vascular risk factors,vessel diameters,and total intracranial volume,was analyzed by multiple linear regression.the Student’ t test or chi square test was used to compare the clinical difference between vertigo group and non-vertigo group.Results:1.For deep white matter hyperintensity,Kendall’ w coefficient of three radiologists was 0.469,which was consistent(P < 0.001).For periventricular white matter hyperintensity,Kendall’ w coefficient was 0.374,and the possibility of inconsistency was as high as 6%(P = 0.06).For the total score of Fazekas scale,the Kendall’ w coefficient was 0.549,which was consistent(P < 0.001).2.Increased tortuosity of bilateral distal internal carotid artery was related to higher white matter hyperintensity volume(right: β=11.223,P=0.016;left: β=20.701,P<0.001).This relationship was independent of advanced age and high blood pressure.And they have been considered as the strongest risk factors for white matter hyperintensity.3.Tortuosity index of basilar artery in vertigo group was higher than that in nonvertigo group(P = 0.007).The incidence of diabetes was higher in vertigo group(P =0.007).However,there were no significant differences in tortuosity index of bilateral distal internal carotid artery,gender,age(≥ 70 years vs < 70 years),CAD,hypertension,white matter hyperintensity volume,total intracranial volume,basilar artery diameter and bilateral distal internal carotid artery diameter between vertigo group and nonvertigo group.Conclusions:1.The score of Fazekas scale was positively correlated with white matter hyperintensity volume,but it was easily affected by the experience of the rater.2.Tortuosity of bilateral distal internal carotid artery is related to white matter hyperintensity,independently of advanced age and high blood pressure.The association may be explained by the changes of cerebral hemodynamics caused by the increase of tortuosity of bilateral distal internal carotid artery.3.Tortuosity index of basilar artery in vertigo group was higher than that in non-vertigo group.