J Clin Neurol.  2010 Dec;6(4):189-195. 10.3988/jcn.2010.6.4.189.

Zonisamide Changes Unilateral Cortical Excitability in Focal Epilepsy Patients

• Joo EY
• Kim HJ
• Lim YH
• Ji KH
• Hong SB

• KMID: 1462805
• DOI: http://doi.org/10.3988/jcn.2010.6.4.189

Abstract

BACKGROUND AND PURPOSE
To evaluate changes in cortical excitability induced by zonisamide (ZNS) in focal epilepsy patients.
METHODS
Twenty-four drug-nasmall yi, Ukrainianve focal epilepsy patients (15 males; overall mean age 29.8 years) were enrolled. The transcranial magnetic stimulation parameters obtained using two Magstim 200 stimulators were the resting motor threshold, amplitude of the motor-evoked potential (MEP), cortical silent period, short intracortical inhibition, and intracortical facilitation. These five transcranial magnetic stimulation parameters were measured before and after ZNS, and the findings were compared.
RESULTS
All 24 patients were treated with ZNS monotherapy (200-300 mg/day) for 8-12 weeks. After ZNS, MEP amplitudes decreased (-36.9%) significantly in epileptic hemispheres (paired t-test with Bonferroni's correction for multiple comparisons, p<0.05), whereas the mean resting motor threshold, cortical silent period, short intracortical inhibition, and intracortical facilitation were unchanged (p>0.05). ZNS did not affect cortical excitability in nonepileptic hemispheres.
CONCLUSIONS
These findings suggest that ZNS decreases cortical excitability only in the epileptic hemispheres of focal epilepsy patients. MEP amplitudes may be useful for evaluating ZNS-induced changes in cortical excitability.

Keyword

transcranial magnetic stimulation; focal epilepsy; zonisamide; cortical excitability

MeSH Terms

Epilepsies, Partial
Humans
Isoxazoles
Transcranial Magnetic Stimulation
Isoxazoles

Figure

• 

  Fig. 1 Changes in motor evoked potential (MEP) amplitudes after zonisamide (ZNS) administration in epilepsy patients. After ZNS treatment, MEP amplitudes were significantly reduced at 120%, 140%, and 150% of the resting motor threshold (RMT) stimulation only in epileptic hemispheres. *Paired t-test after applying Bonferroni's correction for multiple comparisons (p<0.05). Data are presented as medians (horizontal lines through the boxes) with the first and third quartiles (lower and upper lines, respectively) and the smallest and largest values (whiskers extending from the ends of the boxes). Pre-ZNS: before ZNS administration, Post-ZNS: after the ZNS administration, RMT: resting motor threshold.

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