HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Correspondence: Submit a response Alert me when this article is cited Alert me when Correspondence are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Rosati, A. Articles by Dubeau, F. Search for Related Content PubMed PubMed Citation Articles by Rosati, A. Articles by Dubeau, F. Related Collections All Epilepsy/Seizures EEG Epilepsy monitoring Video/ EEG use in epilepsy Cortical localization Partial seizures

Intractable temporal lobe epilepsy with rare spikes is less severe than with frequent spikes

From the Department of Neurology and Neurosurgery, Montreal Neurological Institute and Hospital, Quebec, Canada.

Address correspondence and reprint requests to Dr. François Dubeau, Montreal Neurological Institute and Hospital, 3801 University St., Rm. 138, Montreal, Quebec, Canada H3T 1R2; e-mail: francois.dubeau{at}much.mcgill.ca

Objective: To analyze clinical, electrophysiologic, and neuroradiologic characteristics of a group of patients with nonlesional intractable temporal lobe epilepsy (TLE) and rare or absent interictal epileptiform abnormalities (IEA).

Methods: Between 1990 and 2000, 31 patients (11 men; mean ± SD age 34.3 ± 11.7 years) with nonlesional intractable TLE were consecutively selected on the basis of the absence or paucity of IEA (<1/h) on serial scalp EEG recording; these were defined as "oligospikers." The clinical and laboratory characteristics of oligospikers were compared with those of a group of 27 age-matched control subjects (10 men; mean ± SD age 38.5 ± 11 years), randomly selected from a pool of patients with nonlesional TLE with frequent IEA.

Results: Oligospikers showed a later age at seizure onset (mean ± SD 19.1 ± 14.4 versus 10.2 ± 7.4 years; p = 0.004), lower monthly frequency of complex partial seizures (median 6 versus 12; p = 0.035), lower incidence of secondarily generalized tonic-clonic seizures (10 versus 81%; p < 0.001), and no status epilepticus (0 versus 22%) than control subjects. Also, hippocampal atrophy (HA) was less commonly found in oligospikers (55 versus 96%; p = 0.001). However, there were no differences between the two groups in the frequency of family history of epilepsy, risk factors, febrile convulsions, and type of medication. Twenty-three (74%) oligospikers and 25 (93%) control patients underwent either a selective amygdalohippocampectomy or corticoamygdalohippocampectomy. Excellent surgical outcome (Engel’s Class Ia) was found in 14 of 23 (61%) oligospikers and 17 of 25 (67%) control patients.

Conclusions: This study identified a subgroup of patients with nonlesional intractable TLE with no or few IEA. Oligospikers have a later age at seizure onset, less frequent and less severe seizures, besides a lower incidence of HA. The similarity of etiologic factors compared with patients with frequent IEA suggests that the rarity of spikes could reflect a disease not really distinct but less severe, even though still intractable and incapacitating enough to consider surgery. In spite of the absence or paucity of IEA, oligospikers have excellent surgical outcome.

This article has been cited by other articles:

				J. W. Miller and J. Gotman The meaning of interictal spikes in temporal lobe epilepsy: Should we count them? Neurology, August 5, 2008; 71(6): 392 - 393. [Full Text] [PDF]

				R. Krendl, S. Lurger, and C. Baumgartner Absolute spike frequency predicts surgical outcome in TLE with unilateral hippocampal atrophy Neurology, August 5, 2008; 71(6): 413 - 418. [Abstract] [Full Text] [PDF]