Application of the McDonald MRI criteria in multiple sclerosis.
BACKGROUND
The aim of this study was to assess the sensitivity of McDonald's magnetic resonance imaging (MRI) criteria for the diagnosis of multiple sclerosis (MS) in a group of Asian patients diagnosed with clinically definite MS, based on lesion characterisation on MRI scans.


METHODS
Forty-nine patients from 3 major neurological institutions were classified as having Asian- or Western-type MS based on clinical assessment. Each MRI scan was reviewed by 2 neuroradiologists for the presence and characteristics of brain and spinal lesions. The McDonald's MRI criteria were then applied and its sensitivity evaluated.


RESULTS
Nine patients were excluded, leaving 34 females and 6 males who were dominantly Chinese (90%), with a mean age of 36.2 years. The MRI brain and spinal findings were detailed and tabulated. Statistically significant differences (P <0.01) in MRI brain findings and sensitivity of McDonald's MRI criteria were found between our Asian- and Western-type MS patients. The diagnostic yield of McDonald's MRI criteria increased by 20% when we substituted a cord for a brain lesion, and applied the substitution for enhancing cord lesions as well.


CONCLUSIONS
The diagnosis is more likely to be made when using McDonald MRI criteria based on brain findings, in a patient who presents clinically with Western-type MS. The provision for substitution of "one brain for a spinal lesion" is helpful in Asian-type MS, where there is preponderance of spinal lesion load. Our findings suggest that minor modifications in the interpretation of McDonald's MRI criteria have significant impact on the diagnosis in patients clinically presenting as Asian-type MS, with potential bearing on their subsequent management.
Chan
Ling Ling
LL
Department of Diagnostic Radiology, Singapore General Hospital, Singapore. gdrcll@sgh.com.sg
Sitoh
Yih Yian
YY
Chong
June
J
See
Siew Ju
SJ
Umapathi
Thirugnanam N
TN
Lim
Shih Hui
SH
Ong
Benjamin
B
D000328:Adult; D001930:Brain Injuries / Q000175:diagnosis* / Q000473:pathology; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008485:Medical Audit; D009103:Multiple Sclerosis / Q000145:classification / Q000175:diagnosis*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012846:Singapore; D013119:Spinal Cord Injuries / Q000175:diagnosis / Q000473:pathology