HIPPOCAMPAL ATROPHY IN PATIENTS WITH GENERALIZED TONIC-CLONIC SEIZURES DURING SLEEP
Abstract number :
3.153
Submission category :
Year :
2002
Submission ID :
1830
Source :
www.aesnet.org
Presentation date :
12/7/2002 12:00:00 AM
Published date :
Dec 1, 2002, 06:00 AM
Authors :
Carlos A.M. Guerreiro, Eliane Kobayashi, Li Li Min, Fernando Cendes. Department of Neurology, FCM UNICAMP, Campinas, SP, Brazil; Department of Neurology, FCM UNICAMP, Campinas, SP, Brazil; Department of Neurology, FCM UNICAMP, Campinas, SP, Brazil; Depart
RATIONALE: Patients with seizures exclusively during sleep are frequently well controlled, and are not routinely scanned. Mesial temporal lobe epilepsy (MTLE) can have a benign clinical course and may present with seizures exclusively during sleep. The frequence of hippocampal abnormalities in patients with nocturnal seizures is most likely underestimated.
The objective of this study is to evaluate hippocampal volumes in patients with epilepsy presenting exclusivelly with generalized tonic-clonic seizures (GTCS) during sleep.
METHODS: We evaluated 900 consecutive patients from UNICAMP epilepsy clinic and identified patients with seizures during sleep time only. We excluded those patients with abnormal neurological examination or with clearcut lesions on CT scan. All patients underwent high resolution MRI in a 2T scanner, with acquisitions in three orthogonal planes, including a 3mm coronal T1-IR protocol for volumetric studies. A control group composed by 20 healthy volunteers was used to determine normal parameters. Absolute volumes corrected for variation in total brain volume, as well as asymmetry index were determined for each subject. Values below 2 standard deviations from the mean of control group were considered abnormal.
RESULTS: We identified 18 patients (8 women) with seizures exclusivelly during sleep time: eight with witnessed onset, semiologically compatible with complex partial seizures (CPS) with secondary generalization. All had well controlled seizures and the majority are seizure-free for at least 2 years. HA was identified in 14/18 (78%) patients: 7 unilateral (all left) and 7 bilateral (2 asymmetrical). None of these patients had T2 hyperintense hippocampal signal on MRI. Only one of the patients with normal hippocampal volumes had partial onset identified by clinical history and EEG epileptiform discharges in the temporal lobe. Although the other three patients with normal volumes had no clinical evidence of partial seizure, their interictal EEGs showed temporal slow waves.
CONCLUSIONS: Although we did not observe hyperintense T2 signal, HA determined by volumetry was found in a large proportion of patients with GTCSs during sleep. MRI is important for syndromic diagnosis of patients with nocturnal seizures.
[Supported by: FAPESP, S[atilde]o Paulo, Brazil]