Improved detection of cortical MS lesions with phase-sensitive inversion recovery MRI.
OBJECTIVE
Cortical grey matter lesions are common in multiple sclerosis (MS), but usually not seen on MRI. The authors compared the performance of double inversion recovery (DIR, currently considered the best available imaging sequence for detecting cortical lesions) with phase-sensitive inversion recovery (PSIR, a sequence allowing much higher resolution scans to be obtained in a clinically feasible time).


METHODS
Sixty MS patients and 30 healthy controls underwent MRI scanning on a 3 Tesla scanner. The authors compared intracortical (IC) and leucocortical (LC) lesion counts obtained with a standard DIR sequence (1×1×3 mm resolution, obtained in 4 min) and a PSIR sequence (0.5×0.5×2 mm, 11 min). Lesions were marked separately on DIR and PSIR scans.


RESULTS
In the whole MS cohort, more cortical lesions were seen on the higher-resolution PSIR than the DIR scans (IC mean±SD: 18.1±9.8 vs 5.9±4.5, p<0.001; LC mean±SD: 13.4±12.9 vs 7.3±8.0, p<0.001). On PSIR, ≥1 IC lesion was seen in 60/60 MS patients and 1/30 controls, and ≥1 LC lesion in 60/60 patients and 6/30 controls. On DIR, ≥1 IC lesion was seen in 50/60 patients and 0/30 controls, and ≥1 LC lesion(s) in 60/60 patients and 5/30 controls.


CONCLUSIONS
Compared with DIR, using PSIR the authors are able to detect a significantly greater number of cortical grey matter lesions. The presence of at least one IC lesion in every MS patient, but very few healthy controls, suggests that it may be a useful adjunct to conventional MRI when a diagnosis of MS is suspected but not confirmed.
Queen Square MS Center, NMR Research Unit, Department of Neuroinflammation, UCL Institute of Neurology, London, UK. varun.sethi.09@ucl.ac.uk
Varun
V
Sethi
Tarek A
TA
Yousry
Nils
N
Muhlert
Maria
M
Ron
Xavier
X
Golay
Claudia
C
Wheeler-Kingshott
David H
DH
Miller
Declan T
DT
Chard
D000293:Adolescent; D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D002540:Cerebral Cortex / Q000473:pathology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000473:pathology*; D036421:Nerve Fibers, Unmyelinated / Q000473:pathology; D059906:Neuroimaging / Q000379:methods*