BACKGROUND AND PURPOSE The usefulness of contrast-enhanced 3D T2-FLAIR MR imaging for the evaluation of leptomeningeal diseases has not been systematically investigated. The purpose of this study was to assess the value added by contrast-enhanced 3D T2-FLAIR and MPRAGE sequences to conventional postcontrast T1-weighted images in the evaluation of leptomeningeal diseases. We also undertook in vi...

BACKGROUND AND PURPOSE The FLAIR (fluid-attenuated inversion-recovery) pulse sequence has been shown to be sensitive to abnormalities of the subarachnoid space. Our clinical experience led us to investigate whether intravenously injected contrast material can affect the appearance of the subarachnoid space on FLAIR MR images. METHODS After noting unexplained high signal in the subarachnoid sp...

Background and Purpose—It has recently been proposed that fluid-attenuated inversion recovery (FLAIR) imaging may serve as a surrogate marker for time of symptom onset after stroke. We assessed the hypothesis that FLAIR imaging could be used to decide if an MRI was performed within 4.5 hours from symptom onset or later. Methods—All consecutive patients with presumed stroke who underwent an MRI ...

PURPOSE Hyperintense vessels (HVs) on fluid-attenuated inversion recovery (FLAIR) imaging are associated with the leptomeningeal collateral circulation in cases of arterial occlusive lesions. Nevertheless, the relationship between HVs on FLAIR imaging and arterial circulation time (ACT) on cerebral angiography has not been defined. METHODS We analyzed images of 11 patients with acute occlusio...

BACKGROUND AND PURPOSE T1-weighted spin-echo imaging has been widely used to study anatomic detail and abnormalities of the brain; however, the image contrast of this technique is often poor, especially at low field strengths. We tested a new pulse sequence, T1-weighted fluid-attenuated inversion recovery (FLAIR), which provides good contrast between lesions, surrounding edematous tissue, and n...

Introduction: Many clinical MRI protocols use the fluid attenuated inversion recovery (FLAIR) contrast to better delineate tissue abnormalities such as white matter lesions. Most FLAIR protocols acquire data in a 2D fashion. FLAIR images are often degraded by patient motion, especially when scanning uncooperative patients. Typical motion patterns induce inter-slice misalignment, ghosting and bl...

The purpose of this study was to elucidate which white matter (WM)-tracts are visualized on heavily T2-weighted three-dimensional fluid-attenuated inversion-recovery (hT2w-3D-FLAIR) images. Records of seven patients who underwent hT2w-3D-FLAIR and diffusion tensor imaging (DTI) of the head at 3 Tesla were analyzed. Two neuroradiologists determined WM-tracts visualized on hT2w-3D-FLAIR and ident...

BACKGROUND AND PURPOSE In acute stroke, the DWI-FLAIR mismatch allows for the allocation of patients to the thrombolysis window (<4.5 hours). FLAIR-lesions, however, may be challenging to assess. In comparison, DWI may be a useful bio-marker owing to high lesion contrast. We investigated the performance of a relative DWI signal intensity (rSI) threshold to predict the presence of FLAIR-lesions ...

With the introduction of the fast fluid-attenuated inversion-recovery (FLAIR) magnetic resonance (MR) technique, the routine use of this imaging sequence to enhance the detection of intracranial lesions in the cortical and subcortical regions and deep white matter has become practical, as illustrated so well in Thurnher et al’s article in this issue of AJNR (1). The diagnostic advantages of FLA...

BACKGROUND AND PURPOSE Hyperintense vessels on baseline FLAIR MR imaging of patients with ischemic stroke have been linked to leptomeningeal collateralization, yet the ability of these to maintain viable ischemic tissue remains unclear. We investigated whether hyperintense vessels on FLAIR are associated with the severity of hypoperfusion and response to thrombolysis in patients treated with in...