Deep EEG recordings of the mammillary body in epilepsy patients.
OBJECTIVE
To our knowledge, the epileptic and nonepileptic electroencephalographic (EEG) discharges recorded within the human mammillary body (MB) and mammillothalamic tract (MTT) areas have never been published. Herein, we present the EEG recordings from these structures in patients with refractory epilepsy (RE).


METHODS
Three men (ages 41-43 years) were enrolled in a clinical trial for deep brain stimulation (DBS) of MB-MTT in RE. Previous evaluations had demonstrated a low likelihood of successful response to medication or resective surgery. DBS macroelectrodes were bilaterally implanted within the MB-MTT under general anesthesia and their location checked by magnetic resonance imaging (MRI). We obtained a surface-depth EEG for a 2- to 4-day period, including monitoring of the cardiorespiratory and mnemonic functions.


RESULTS
The background pattern of EEG recorded from MB-MTT was low-amplitude (usually <25 microv for MB and <20 microv for MTT) waves with a variable combination of theta-beta rhythms. In two patients, pseudoperiodic slow spikes were unilaterally recorded with or without clinical signs. For one patient, several focal ictal discharges were recorded in the right MB without scalp EEG changes.


CONCLUSIONS
The analysis of our depth EEG revealed that the theta-beta pattern represents the predominant physiologic profile of MB. Paroxysmal epileptiform discharges can be observed in human MB. These data supplement those available from animal observations.
van Rijckevorsel
Kenou
K
Department of Neurology, Reference Center for Refractory Epilepsy, Saint-Luc Hospital, Université Catholique de Louvain, Brussels, Belgium. vanrijckevorsel@nops.ucl.ac.be
Abu Serieh
Basel
B
de Tourtchaninoff
Marianne
M
Raftopoulos
Christian
C
D000328:Adult; D004567:Electrodes, Implanted; D004569:Electroencephalography / Q000379:methods / Q000706:statistics & numerical data*; D004827:Epilepsy / Q000175:diagnosis* / Q000503:physiopathology; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D008297:Male; D008326:Mammillary Bodies / Q000503:physiopathology*; D009434:Neural Pathways / Q000503:physiopathology; D013788:Thalamus / Q000503:physiopathology