Brain Excitability Changes in the Relapsing and Remitting Phases of Multiple Sclerosis: A Study with Transcranial Magnetic Stimulation

[摘要] Background: Multiple sclerosis (MS) is the most common disabling neurological disease in young adults characterized by recurrent relapses and/or progression. Multiple sclerosis was the first neurological disease in which transcranial magnetic stimulation (TMS) was used. Objective: The aim of this study is to assess the relationship between the level of cerebral excitability and clinical phase of MS (the relapsing and remitting phases of MS). Methods: Forty patients affected by relapsing-remitting (RR) MS were examined using single TMS in order to assess excitability changes in the hand motor cortex occurring during relapse and/or remission of the disease. The analyzed parameters were: motor threshold, amplitude of motor evoked potential (MEP), silent period (SP), and central motor conduction time (CMCT). Results: The analysis of variance exhibited a strong correlation (P<0.001) between the clinical phase and the type of excitability changes: ‘relapsing’ patients showed increased threshold and reduced SP duration. ‘By contrast, ‘remitting’ patients showed a significant SP prolongation with normal motor thresholds. Conclusion:  TMS is a highly sensitive non invasive technique recommended to evaluate conduction abnormalities and cortical excitability changes and in monitoring the course of the disease in relapsing-remitting MS. [Egypt J Neurol Psychiat Neurosurg.  2010; 47(4): 535-340]

[学科分类] 精神健康和精神病学