Document Type: Letter to the Editor

Authors

1 Multiple Sclerosis Research Center, Neuroscience Institute, Department of Neurology, Sina Hospital, Tehran University of Medical Sciences, ‎Tehran, Iran

2 ‎Department of Neurology, Sina Hospital, Tehran University of Medical Sciences, Tehran, ‎Iran

3 Department of Neurology, Sina Hospital, Tehran University of Medical Sciences, Tehran, ‎Iran