Neurology
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Figures Only
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Correspondence:
Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when Correspondence are posted
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Canafoglia, L.
Right arrow Articles by Franceschetti, S.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Canafoglia, L.
Right arrow Articles by Franceschetti, S.
Related Collections
Right arrow Metabolic disease (inherited)
Right arrow Myoclonus
Right arrow Evoked Potentials/Somatosensory
NEUROLOGY 2004;63:2309-2315
© 2004 American Academy of Neurology

Sensorimotor cortex excitability in Unverricht–Lundborg disease and Lafora body disease

L. Canafoglia, MD, C. Ciano, MD, F. Panzica, PhD, V. Scaioli, MD, C. Zucca, MD, P. Agazzi, MD, E. Visani, PhD, G. Avanzini, MD and S. Franceschetti, MD

From the Department of Clinical Neurophysiology (Drs. Canafoglia, Ciano, Panzica, Scaioli, Agazzi, Visani, Avanzini, and Franceschetti), IRCCS National Neurological Institute C. Besta, Milano, and Department of Neurophysiopatholology (Dr. Zucca), IRCCS E. Medea, Bosisio Parini, Italy.

Address correspondence and reprint requests to Dr. S. Franceschetti, C. Besta National Neurologic Institute, Via Celoria 11, 20133 Milano, Italy; e-mail: franceschetti{at}istituto-besta.it

Objective: To investigate whether Unverricht–Lundborg disease (ULD) and Lafora body disease (LBD) can be differentiated on the basis of their neurophysiologic profiles.

Methods: Somatosensory evoked potentials (SSEPs), long-loop reflexes (LLRs), and the influence of conditioning nerve stimulation on the motor potentials evoked by transcranial stimulation in 8 patients with LBD and 10 patients with ULD were investigated.

Results: Both groups showed sensorimotor cortex hyperexcitability, but their electrophysiologic profiles were different. Enlarged P25 to N33 SSEP components and enhanced LLRs were common in the ULD patients, whereas medium-latency "giant" SSEP components and less consistently enhanced LLRs were more frequently found in the patients with LBD. Cortical relay time was extremely brief in ULD but varied in LBD. Conditioning somatosensory stimuli differently affected motor cortex excitability, leading to early facilitation in ULD and delayed and prolonged facilitation in LBD.

Conclusions: Patients with Unverricht–Lundborg disease (ULD) and Lafora body disease (LBD) have different electrophysiologic profiles. The ULD findings point to an aberrant subcortical or cortical loop (possibly short-cutting the somatosensory cortex) that is involved in generating the prominent action myoclonus characterizing the disorder. The LBD findings highlight sustained hyperexcitability of the sensorimotor cortex in response to afferent stimuli, which fit with a more severe impairment of inhibitory mechanisms.

Received April 23, 2004. Accepted in final form August 2, 2004.






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 2004 by AAN Enterprises, Inc.