Association between carotid artery dissection and vascular tortuosity: a case-control study.

PURPOSE We aimed to verify if vascular tortuosity (VT) may represent a risk factor for spontaneous epiaortic vessel dissection (sEVD) in young adult patients. METHODS We identified 304 patients aged under 55 years consecutively admitted for acute cerebrovascular events to our Stroke Unit. After checking the possibility to perform a 3D reconstruction of epiaortic vessels on CT-angiography images, we selected and compared fifty patients with sEVD (cases) with fifty-one patients without dissection (controls). VT of carotid and vertebral arteries was measured on reconstructions evaluating the vascular tortuosity index (VTI), calculated according to a specific algorithm, and the presence of kinking and coiling. Differences between groups were analyzed by Student-t test for numeric variables and chi-square test for categoric ones. A ROC curve analysis was used to look for a VTI threshold value beyond which the risk of dissection was significantly increased. RESULTS VTI was significantly higher in cases than in controls only considering carotid arteries (p = 0.029); cases did not have a significantly higher rate of kinking and coiling than controls (p = 0.059 and 0.077, respectively). We have found a significant VTI threshold value of 27.9% (under curve area = 61.6%, p = 0.04) only for carotid artery dissection. CONCLUSION VT appears to be associated with an increased risk of dissection for the carotid district but not for the vertebral one. The different structure, embryogenesis, and pathophysiology of dissection between the two districts could explain this finding. VTI threshold as carotid artery dissection predictor deserves confirmation in larger studies.