Cortical excitability and Refractory epilepsy: a Three-Year longitudinal Transcranial Magnetic Stimulation Study

Transcranial magnetic stimulation was used to study the effect of recurrent seizures on cortical excitability over time in epilepsy. 77 patients with firm diagnoses of idiopathic generalized epilepsy (IGE) or focal epilepsy were repeatedly evaluated over three years. At onset, all groups had increased cortical excitability. At the end of follow-up the refractory group was associated with a broad increase in cortical excitability. Conversely, cortical excitability decreased in all seizure free groups after introduction of an effective medication.

[1]  Ali Fatemi-Ardekani,et al.  Transcranial magnetic stimulation: physics, electrophysiology, and applications. , 2008, Critical reviews in biomedical engineering.

[2]  Mark Newton,et al.  Changes in cortical excitability differentiate generalized and focal epilepsy , 2007, Annals of neurology.

[3]  W. Oertel,et al.  Motor cortex excitability in focal epilepsies not including the primary motor area--a TMS study. , 2005, Brain : a journal of neurology.

[4]  Jacob Cohen Statistical Power Analysis for the Behavioral Sciences , 1969, The SAGE Encyclopedia of Research Design.

[5]  G Colicchio,et al.  Effects of vagus nerve stimulation on cortical excitability in epileptic patients , 2004, Neurology.

[6]  S Noachtar,et al.  Motor cortex excitability in patients with focal epilepsy , 2000, Epilepsy Research.

[7]  P. Kwan,et al.  Early identification of refractory epilepsy. , 2000, The New England journal of medicine.

[8]  G Zanette,et al.  Hyperexcitable cortical responses in progressive myoclonic epilepsy , 2001, Neurology.

[9]  M G Marciani,et al.  Transcranial magnetic stimulation reveals an interhemispheric asymmetry of cortical inhibition in focal epilepsy , 2000, Neuroreport.

[10]  G Zanette,et al.  Early and Late Intracortical Inhibition in Juvenile Myoclonic Epilepsy , 2000, Epilepsia.

[11]  C Iani,et al.  Distinguishing forms of generalized epilepsy using magnetic brain stimulation. , 1996, Electroencephalography and clinical neurophysiology.

[12]  R. C. Oldfield The assessment and analysis of handedness: the Edinburgh inventory. , 1971, Neuropsychologia.

[13]  J. Sander,et al.  Hippocampal damage caused by seizures in temporal lobe epilepsy , 1998, The Lancet.

[14]  Paolo Maria Rossini,et al.  Transcranial magnetic stimulation , 2007, Neurology.

[15]  A. Berardelli,et al.  Effects of diazepam, baclofen and thiopental on the silent period evoked by transcranial magnetic stimulation in humans , 1996, Experimental Brain Research.

[16]  C. Boccagni,et al.  Cortical excitability in drug-naive patients with partial epilepsy , 2004, Neurology.

[17]  Gregory L. Holmes,et al.  Seizure-induced neuronal injury: Animal data , 2002, Neurology.

[18]  Andrew M. White,et al.  Development of Spontaneous Seizures after Experimental Status Epilepticus: Implications for Understanding Epileptogenesis , 2007, Epilepsia.

[19]  Graeme D Jackson,et al.  Predicting seizure control: Cortical excitability and antiepileptic medication , 2010, Annals of neurology.

[20]  P. Rossini,et al.  Non-invasive electrical and magnetic stimulation of the brain, spinal cord and roots: basic principles and procedures for routine clinical application. Report of an IFCN committee. , 1994, Electroencephalography and clinical neurophysiology.

[21]  Asla Pitkänen,et al.  Is epilepsy a progressive disorder? Prospects for new therapeutic approaches in temporal-lobe epilepsy , 2002, The Lancet Neurology.

[22]  L Forsgren,et al.  Incidence and Clinical Characterization of Unprovoked Seizures in Adults: A Prospective Population‐Based Study , 1996, Epilepsia.

[23]  M. Newton,et al.  Sleep deprivation increases cortical excitability in epilepsy , 2006, Neurology.

[24]  M. Fujiki,et al.  The relationship between paired pulse magnetic MEP and surgical prognosis in patients with intractable epilepsy , 2007, Seizure.

[25]  A. Pitkänen,et al.  Recurrent seizures may cause hippocambal damage in temporal lobe epilepsy , 1998, Neurology.

[26]  G. Mathern,et al.  Definition of drug resistant epilepsy: Consensus proposal by the ad hoc Task Force of the ILAE Commission on Therapeutic Strategies , 2009, Epilepsia.

[27]  J C Rothwell,et al.  Mirtazapine increases cortical excitability in healthy controls and epilepsy patients with major depression , 2005, Journal of Neurology, Neurosurgery & Psychiatry.

[28]  Aysun Soysal,et al.  Cortical excitability in juvenile myoclonic epileptic patients and their asymptomatic siblings: A transcranial magnetic stimulation study , 2009, Seizure.

[29]  Graeme Jackson,et al.  The peri-ictal state: cortical excitability changes within 24 h of a seizure. , 2009, Brain : a journal of neurology.

[30]  R A Wennberg,et al.  Changes in motor cortex excitability with stimulation of anterior thalamus in epilepsy , 2006, Neurology.

[31]  Ulf Ziemann,et al.  Suppression of LTP-like plasticity in human motor cortex by the GABAB receptor agonist baclofen , 2007, Experimental Brain Research.

[32]  J. French,et al.  Refractory Epilepsy: One Size Does Not Fit All , 2006, Epilepsy currents.

[33]  G Zanette,et al.  Effects of sleep deprivation on cortical excitability in patients affected by juvenile myoclonic epilepsy: a combined transcranial magnetic stimulation and EEG study , 2005, Journal of Neurology, Neurosurgery & Psychiatry.

[34]  Janine Reis,et al.  Cyclical excitability of the motor cortex in patients with catamenial epilepsy: A transcranial magnetic stimulation study , 2006, Seizure.

[35]  F. Dudek,et al.  Epileptogenesis in the dentate gyrus: a critical perspective. , 2007, Progress in brain research.

[36]  Ulf Ziemann,et al.  Inhibitory circuits and the nature of their interactions in the human motor cortex – a pharmacological TMS study , 2008, The Journal of physiology.

[37]  K. Werhahn,et al.  Recruitment of motor cortex inhibition differentiates between generalized and focal epilepsy , 2009, Epilepsy Research.

[38]  Graeme D Jackson,et al.  Can changes in cortical excitability distinguish progressive from juvenile myoclonic epilepsy? , 2010, Epilepsia.

[39]  Simone Rossi,et al.  Transcranial magnetic stimulation , 2007, Neurology.

[40]  Esa Mervaala,et al.  Altered cortical inhibition in Unverricht–Lundborg type progressive myoclonus epilepsy (EPM1) , 2009, Epilepsy Research.

[41]  D. Mott,et al.  The pharmacology and function of central GABAB receptors. , 1994, International review of neurobiology.

[42]  R. C. Oldfield THE ASSESSMENT AND ANALYSIS OF HANDEDNESS , 1971 .

[43]  C. Marsden,et al.  Corticocortical inhibition in human motor cortex. , 1993, The Journal of physiology.

[44]  Andreas Schulze-Bonhage,et al.  Changes in intracortical excitability after successful epilepsy surgery , 2008, Epilepsy Research.

[45]  Alan C. Evans,et al.  Longitudinal and cross-sectional analysis of atrophy in pharmacoresistant temporal lobe epilepsy , 2009, Neurology.

[46]  Samuel F. Berkovic,et al.  Human epilepsies: interaction of genetic and acquired factors , 2006, Trends in Neurosciences.

[47]  G. Cascino,et al.  When drugs and surgery don’t work , 2008, Epilepsia.

[48]  G. Migliaretti,et al.  Cortical Excitability in Cryptogenic Localization‐Related Epilepsy: Interictal Transcranial Magnetic Stimulation Studies , 2000, Epilepsia.

[49]  F Cendes,et al.  Seizure frequency and lateralization affect progression of atrophy in temporal lobe epilepsy , 2009, Neurology.

[50]  G. Jackson,et al.  Why do seizures in generalized epilepsy often occur in the morning? , 2009, Neurology.

[51]  Gary W. Mathern,et al.  Erratum: Definition of drug resistant epilepsy. Consensus proposal by the ad hoc task force of the ILAE commission on therapeutic strategies (Epilepsia (2010) 51 (1069-77)) , 2010 .

[52]  Ulf Ziemann,et al.  Chapter 23 Pharmacology of TMS , 2003 .

[53]  J. Lefaucheur,et al.  La stimulation magnétique transcrânienne : applications en Neurologie , 2005 .

[54]  Simon Shorvon,et al.  Handbook of Epilepsy Treatment , 2000 .

[55]  Paolo Manganotti,et al.  Motor Responses to Afferent Stimulation in Juvenile Myoclonic Epilepsy , 2004, Epilepsia.

[56]  N Mavroudakis,et al.  Effects of vigabatrin on motor potentials evoked with magnetic stimulation. , 1997, Electroencephalography and clinical neurophysiology.

[57]  B. Greenberg,et al.  Menstrual cycle effects on cortical excitability , 1999, Neurology.

[58]  A. Marson,et al.  Immediate versus deferred antiepileptic drug treatment for early epilepsy and single seizures: a randomised controlled trial , 2005, The Lancet.

[59]  Ari Syngeniotis,et al.  Seizure‐associated hippocampal volume loss: A longitudinal magnetic resonance study of temporal lobe epilepsy , 2002, Annals of neurology.

[60]  Ulf Ziemann,et al.  TMS and drugs , 2004, Clinical Neurophysiology.

[61]  S Shinnar,et al.  Do seizures beget seizures? An assessment of the clinical evidence in humans. , 1997, Journal of clinical neurophysiology : official publication of the American Electroencephalographic Society.

[62]  Babak Boroojerdi,et al.  Pharmacologic Influences on TMS Effects , 2002, Journal of clinical neurophysiology : official publication of the American Electroencephalographic Society.

[63]  S. Berkovic,et al.  Cortical excitability and recovery curve analysis in generalized epilepsy , 1999, Neurology.