Visual Rating of T2’-Blood-Oxygen-Level-Dependent Magnetic Resonance Imaging in Acute Stroke Patients - a Pilot Study

Abstract

Hypo-intense lesions in BOLD imaging were visible and exceeded the lesion in diffusion-weighted imaging in most of the stroke patients. The encouraging results justify further testing of the hypothesis that BOLD lesions, when larger than DWI lesions, are associated with infarct growth from initial DWI to final infarct.

The correlation between quantitative T2′ and regional cerebral blood flow after acute brain ischemia in early reperfusion as demonstrated in a middle cerebral artery occlusion/reperfusion model of the rat

“…They have been used to describe the penumbra in acute stroke patients (Lee et al, 2003;Geisler et al, 2006;Fiehler et al, 2007). This approach is based on a metabolic concept.…”

T2*-Weighted MRI versus Oxygen Extraction Fraction PET in Acute Stroke

“…1 for an illustration). Furthermore, in a pilot report by Fiehler et al [17] involving the same dataset as Geisler et al [16], the interobserver agreement for correctly identifying the affected side was considered ‘fair’ only (ĸ = 0.239), and after unblinding the visibility of the T2’ hypo-intense lesion was considered ‘good’ in only 9 out of 20 patients by consensus, raising questions about the method’s reliability in the clinical setting – notwithstanding that some of the images presented are quite convincing. In a further report from the same group on 100 patients [18], the T2’-apparent diffusion coefficient mismatch had better specificity than the PWI-apparent diffusion coefficient mismatch for predicting infarct growth; however, there was high variability in T2’ lesions visibility and the interobserver reliability was moderate only (ĸ = 0.53).…”

Oxygen Imaging by MRI

“…In a subsequent study, Fiehler and coworkers 35 concluded that T2' may be sensitive to infarct growth, but that the T2' lesion can be difficult to assess visually.…”

“…Eleven experimental studies have used T2* with breathing challenge [25][26][27][28][29][30][31][32][33][34][35] (online-only Data Supplement Table III). During anoxic challenge, image intensity in T2*-weighted images significantly dropped in the core, penumbra, and healthy tissue, but these changes could not clearly differentiate these tissue types without the information from diffusion-weighted imaging.…”