Clinical applications of susceptibility weighted imaging in patients with major stroke

Abstract

Susceptibility weighted imaging (SWI) is a newly developed magnetic resonance (MR) protocol. Recent studies have found that SWI may be useful in the field of cerebrovascular diseases, especially for detecting the presence of prominent veins, microbleeds and the susceptibility vessel sign (SVS). Some authors have even suggested that SWI can be used to predict outcome. We conducted a prospective study of patients hospitalized with middle cerebral artery territory infarction receiving MRI within 2 days of stroke onset. The presence of prominent veins, microbleeds and SVS in SWI was analyzed along with hospital characteristics of the patients. A total of 44 patients were enrolled. Among the 44 patients, 15 (34.1%) patients showed prominent veins, 19 (43.2%) showed SVS, and 14 (31.8%) showed microbleeds. The presence of SVS and prominent veins was not associated with prognosis. Though not statistically significant (p = 0.06), patients with SVS were more likely to develop later brain edema. SVS was significantly associated with arterial occlusion (p = 0.008) based on the MR angiogram, and microbleeds were significantly associated with later hemorrhagic transformation (p = 0.018). In our study, SWI could not be used to predict outcome as previously suggested. However, the presence of microbleeds may predict further hemorrhagic transformation, and the presence of SVS could be used to detect intra-arterial thrombus. Patients with SVS were also more likely to develop later brain edema. Including SWI in routine MR protocols for major acute ischemic stroke would be worthwhile.

The diagnostic value of susceptibility-weighted imaging for ischemic penumbra in patients with acute ischemic stroke

“…It has been reported in the literature [24] that a magnetic resonance angiogram (MRA) and SWI can be used to detect an intracranial artery embolus in a patient with an acute ischemic stroke. Compared with an MRA, however, a susceptibility vessel sign (SVS) is more likely to indicate a clogged artery.…”

“…While Chen and Ni [8] suggested that PDM could replace PET-CT. Additionally, gadolinium, which is introduced during perfusion scans, can induce an allergic reaction in some patients. Huang et al [9] believe that gadolinium may cause nephrogenic systemic fibrosis (NSF), which may trigger renal dysfunction. Kuo et al [10] have also suggested that any contrast agent may cause NSF.…”

Ipsilateral Prominent Thalamostriate Vein on Susceptibility-Weighted Imaging Predicts Poor Outcome after Intravenous Thrombolysis in Acute Ischemic Stroke

“…4,8 However, it was difficult to differentiate cortical veins from leptomeningeal collaterals because there were no obvious morphologic differences between them. 9 Additionally, the anatomic variability of cortical veins also contributes to reduced interrater agreement when assessing the cortical veins. In contrast to cortical veins, leptomeningeal collaterals do not interfere with the assessment of deep cerebral veins, and anatomic variation in deep veins is less prevalent.…”

Magnetic resonance susceptibility weighted imaging in neurosurgery: current applications and future perspectives

“…7,59 SWI can effectively determine the CVS to detect arterial occlusion 49 and the change in CVS preand postadministration of the thrombolytic agent to assess reperfusion levels. 7 Although CVS measurements offer precise information on the thrombotic region, a simpler detection method involves the presence of dilated and hypointense cortical vessels on SW images.…”

“…A limited collection of studies has examined the ability of SWI to monitor outcome in stroke patients; 6,7,49,56,64 however, the method of monitoring stroke outcome has varied greatly between studies. Bai et al 6 have suggested that a greater amount of CMBs on SWI after reperfusion is predictive of a better outcome.…”