BACKGROUND: MR signal loss related to arterial thrombosis leading to vascular susceptibility artifacts (VSA) has recently been reported on gradient echo images. The time course and sensitivity of VSA in acute stroke patients has been scarcely investigated. The aim of this study was to assess the frequency and course of VSA in acute stroke patients, to compare its sensitivity to distinct features of arterial occlusion as detected on FLAIR images or on CT scan. METHODS: Twenty-nine patients were scanned from 45 min to 6 h after stroke onset using identical MR parameters. All had an acute ischemic lesion identified on diffusion-weighted images, 25 had an occlusion of MCA or PCA confirmed by magnetic resonance angiography. RESULTS: VSA was detected in 22/25 patients having an occluded artery at the time of MRI examination. Flair disclosed a hyperintense vessel in all of these 25 cases, but CT scan revealed a hyperdense artery in only 15 cases. Follow-up studies showed that VSA can vanish or disappear after partial recanalization. When the artery remains occluded, VSA can decrease, disappear or increase in the next hours, possibly related to structural modifications of the thrombus with time. Most occlusions were due to cardiac and arterial emboli or to intracranial extension of carotid occlusion. CONCLUSIONS: VSA are frequent in the first hours of MCA or PCA occlusion in acute stroke patients. The sensitivity of VSA appears lower than the arterial hyperintensity on FLAIR images but higher than the hyperdense artery sign on CT scan. The extent and intensity of VSA can change with recanalization or structural modifications of the thrombus. Copyright 2005 S. Karger AG, Basel.
BACKGROUND: MR signal loss related to arterial thrombosis leading to vascular susceptibility artifacts (VSA) has recently been reported on gradient echo images. The time course and sensitivity of VSA in acute strokepatients has been scarcely investigated. The aim of this study was to assess the frequency and course of VSA in acute strokepatients, to compare its sensitivity to distinct features of arterial occlusion as detected on FLAIR images or on CT scan. METHODS: Twenty-nine patients were scanned from 45 min to 6 h after stroke onset using identical MR parameters. All had an acute ischemic lesion identified on diffusion-weighted images, 25 had an occlusion of MCA or PCA confirmed by magnetic resonance angiography. RESULTS: VSA was detected in 22/25 patients having an occluded artery at the time of MRI examination. Flair disclosed a hyperintense vessel in all of these 25 cases, but CT scan revealed a hyperdense artery in only 15 cases. Follow-up studies showed that VSA can vanish or disappear after partial recanalization. When the artery remains occluded, VSA can decrease, disappear or increase in the next hours, possibly related to structural modifications of the thrombus with time. Most occlusions were due to cardiac and arterial emboli or to intracranial extension of carotid occlusion. CONCLUSIONS: VSA are frequent in the first hours of MCA or PCA occlusion in acute strokepatients. The sensitivity of VSA appears lower than the arterial hyperintensity on FLAIR images but higher than the hyperdense artery sign on CT scan. The extent and intensity of VSA can change with recanalization or structural modifications of the thrombus. Copyright 2005 S. Karger AG, Basel.
Authors: Liangfu Zhu; David S Liebeskind; Reza Jahan; Sidney Starkman; Noriko Salamon; Gary Duckwiler; Fernando Vinuela; Satoshi Tateshima; Nestor Gonzalez; Pablo Villablanca; Latisha K Ali; Doojin Kim; Bruce Ovbiagele; Michael Froehler; Matthew Tenser; Jeffrey L Saver Journal: Stroke Date: 2012-01-26 Impact factor: 7.914
Authors: Charlie Chia-Tsong Hsu; Gigi Nga Chi Kwan; Sachintha Hapugoda; Michelle Craigie; Trevor William Watkins; E Mark Haacke Journal: Neuroradiol J Date: 2017-01-01