Measuring the cortical silent period can increase diagnostic confidence for amyotrophic lateral sclerosis.
We evaluated a modified measurement of the cortical silent period (CSP) as a simple procedure to add further confidence in the diagnostic work-up for ALS. Thirty-seven consecutive patients with a suspicion of having ALS were included together with 25 healthy volunteers, and followed until a final diagnosis (ALS versus 'ALS mimic') was reached. Using a CSP cut-off value of 200 ms for males and 150 ms for females, the following test characteristics were obtained for ALS versus ALS mimics together with controls: sensitivity for excluding ALS 0.83, specificity 0.56 (males) and sensitivity 0.81, specificity 0.82 (females). A CSP longer than the mentioned cut-off values should alarm the clinician for the presence of a disorder other than ALS.
Schelhaas
H Jurgen
HJ
Department of Neurology, University Medical Centre Nijmegen, The Netherlands.
Arts
Ilse M
IM
Overeem
Sebastiaan
S
Houtman
Catharina J
CJ
Janssen
Henny
H
Kleine
Bert U
BU
Munneke
Marten
M
Zwarts
Machiel J
MJ
D000368:Aged; D000690:Amyotrophic Lateral Sclerosis / Q000175:diagnosis* / Q000503:physiopathology*; D002540:Cerebral Cortex / Q000503:physiopathology*; D005071:Evoked Potentials; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D012737:Sex Factors