Cortical plaques visualised by fluid-attenuated inversion recovery imaging in relapsing multiple sclerosis.
Fluid-attenuated inversion recovery (FLAIR) imaging with prolonged inversion times allows generation of highly T2-weighted images of the brain with suppression of cerebrospinal fluid signal. Such sequences result in high lesion contrast and allow visualisation of abnormalities not seen with conventional T2-weighted spin-echo sequences. We used FLAIR sequences, proton density (PD) and standard T2-weighted images to examine lesion number and distribution in ten patients with clinically definite relapsing multiple sclerosis (MS). We also studied the extent and distribution of blood-brain-barrier breakdown by gadolinium-enhanced T1-weighted images. FLAIR sequences proved feasible both in terms of acquisition time and image quality using a 0.5 T imager. FLAIR imaging allowed identification of 45% more high-signal lesions than T2-weighted or PD images in the 10 patients. In particular, 60% more lesions within the cortex and at the grey-white interface were identified. Cortical lesions, none of which enhanced following gadolinium-DTPA injection, were present in seven of the ten patients studied. Of all lesions identified, 8% were cortical. FLAIR sequences are more sensitive to cortical and subcortical lesions in patients with active demyelination.
Boggild
M D
MD
Department of Neurology, North Staffordshire Hospital Centre, Stoke-on-Trent, UK.
Williams
R
R
Haq
N
N
Hawkins
C P
CP
D000328:Adult; D002540:Cerebral Cortex / Q000473:pathology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009103:Multiple Sclerosis / Q000175:diagnosis*