Hyperintense vessel sign on MRI FLAIR images in transient ischemic attack

Abstract

Background and Purpose: Hyperintense vessel sign (HVS) is often observed on MRI FLAIR images of cerebral infarction, but its incidence and significance in patients with transient ischemic attack (TIA) has not been assessed. Therefore, we examined acute TIA patients with HVS and clarified their clinical characteristics.Methods: We examined 165 TIA cases whose neurological symptoms disappeared within 24 hours at Nagoya Daini Red Cross Hospital from January 2007 to November 2009 (including 55 cases with positive lesions on MRI diffusion-weighted images). Retrospectively, we examined for the presence of HVS and performed a comparative study between TIA patients with and without HVS.Results: HVS was observed in 16 cases (9.7%). The presence of dysarthria and serum BUN, creatinine, and homocysteine levels were significantly higher and LDL cholesterol was lower in the HVS group. The ABCD² score and the presence of cerebral infarction were not significantly different between both groups. The probability of a ≥50% stenosis in the large craniocervical artery was higher in the HVS group. The most common etiology of TIA in the HVS group was atherosclerosis. The position of HVS corresponded to the clinical features with a high probability of 94%. Four cases had normal MRA despite the existence of HVS. HVS disappeared within an average of 60 days in 80% of patients in the HVS group.Conclusions: Transient HVS could be useful to show objectively the existence of ischemia in acute TIA. It is preferable to perform MRI scans, including FLAIR images, on patients with acute TIA.