A pragmatic approach using magnetic resonance imaging to treat ischemic strokes of unknown onset time in a thrombolytic trial.

ABSTRACT:

Background and purpose

Toward the goal of designing a clinical trial using imaging parameters to treat stroke patients with unknown onset time, we investigated the timing of changes on MRI in patients with well-defined stroke onset.

Methods

Hypothesis-generating (n=85) and confirmatory (n=111) samples were scored by blinded readers for fluid-attenuated inversion recovery (FLAIR) hyperintensity in diffusion-positive regions. Reader-measured signal intensity ratio (SIR) of the lesion to contralateral tissue was compared with SIR measured by coregistration.

Results

Lesion conspicuity increased with time on FLAIR (P=0.006). Qualitative assessment of FLAIR-negative vs FLAIR hyperintensity (k=0.7091; 95% CI, 0.61-0.81) showed good interrater agreement. Subtle hyperintensity

SUBMITTER: Song SS 

PROVIDER: S-EPMC3464959 | biostudies-literature | 2012 Sep

REPOSITORIES: biostudies-literature