Abstracts

RATIONALE: Although reflex epilepsies are a relatively rare group of seizure disorders, they may provide valuable insight into potential mechanisms of epileptogenesis and the organization of functional neuroanatomy. We were the first group to report a case of reflex tooth brushing epilepsy and demonstrate a structural and functional lesion in the peri-rolandic region. Our objective is to describe a further three cases of reflex epilepsy, all consistently associated with tooth-brushing and demonstrable lesions on neuroimaging.
METHODS: Descriptive epidemiological analysis of four cases of tooth brushing epilepsy with structural and functional imaging and electrophysiology.
RESULTS: Magnetic resonance imaging brain scans (MRIBS) were performed in all four cases. In three cases, MRIBS demonstrated circumscribed lesions involving the postcentral gyrus. One case occurred as a post-traumatic event, while the other three were without a clear acquired risk factor. Seizure types included simple partial in four, complex partial seizures in one and secondarily generalized seizures in three. Abnormal neurological examination was noted in two cases with subtle but definite facial weakness of upper motor neuron type. In the three cases that underwent video-telemetry, lateralising epileptiform activity was seen during typically induced events in two cases. Ictal single photon emission computed tomography (SPECT) scan showed an area of hyperperfusion that corresponded to the MRI lesion on coregistration with a surface-matching technique in one case. Subsequent co-registered interictal SPECT scan demonstrated hypoperfusion in the same region in this case. Surgical resection was performed in this case with pathology revealing cortical dysplasia.
CONCLUSIONS: This series of four cases of tooth brushing epilepsy provides further valuable evidence for a structural focus involving the postcentral gyrus. This cerebral localization suggests somatosensory induction may be the likely trigger in this form of reflex epilepsy.
[Supported by: Wendyl D[ssquote]Souza[ssquote]s salary is funded in part by a Epilepsy-Neurophysiology Fellowship from Pzfier Pharmaceuticals. He is also the recipient of the 2002 Royal Australasian College of Physicians GlaxoSmithKline Fellowship in Neurology.]; (Disclosure: Salary - Wendyl DSouza is currently employed as an Epilepsy-Electrophysiology Fellow at the Alfred Hospital with part salary support by Pfizer Pharmaceuticals., Grant - Wendyl DSouza has been awarded the 2002 Royal Austrlasian College of Physicians GlaxoSmithKline Fellowship in Neurology.)