Tooth‐Brushing Epilepsy: A Report of a Case with Structural and Functional Imaging and Electrophysiology Demonstrating a Right Frontal Focus

Abstract

Patients with reflex epilepsies may provide insights into cerebral pathophysiology. We report a patient with an unusual form of reflex epilepsy in whom seizures are induced by tooth brushing. Magnetic resonance imaging (MRI) demonstrated a right posterior frontal low-grade tumor predominantly involving the precentral gyrus. Video-telemetry demonstrated right-sided epileptiform activity during a typical induced complex partial seizure. An ictal single photon emission computed tomography (SPECT) scan showed an area of hyperfusion that corresponded to the MRI lesion on coregistration with a surface-matching technique. A subsequent coregistered interictal SPECT scan demonstrated hypoperfusion in the same region. Ours is the first report to demonstrate a structural focus in this unusual form of reflex epilepsy. Possible mechanisms to explain the induction of the seizures are discussed.

Is it safe to use a toothbrush?

“…Epilepsy associated with toothbrushing is an unusual form of reflex epilepsy in which seizures are precipitated exclusively by the act of brushing the teeth [53][54][55][56]. Such epilepsy involves a persistent rhythmic oral sensory stimulus, which is likely to evoke the neuronal synchronization necessary to induce seizures [57].…”

Trouble at dinner: an unusual case of eating-induced seizures

“…O’Brien and his colleagues proposed that lesions in those patients interfered with the inhibition or processing of sensory inputs to the cortex and, consequently, led to excitation and production of a critical mass of synchronised cortical neurons 4. Although traditionally controversial, seizures of subcortical and infratentorial origin have been demonstrated in animal models and are well documented in patients with hypothalamic hamartomas and cerebellar dysplastic lesions 5 6.…”

Tooth Brushing–Induced Seizures: A Case Report

“…Most recently, O' Brien et al (2) reported a 23‐year‐old woman who had (for the last 10–12 years) partial seizures consisting of tonic posturing of the left arm, head and eye deviation to the left, and left hemifacial jerking. Her seizures were triggered exclusively by vigorous tooth brushing on either side of mouth and were relatively resistant to treatment.…”

“…Reflex epileptic seizures triggered by tooth brushing are rare but well documented. Holmes et al (1982) were the first to describe a patient with seizures consistently but not exclusively provoked by tooth brushing (1), and O'Brien et al (2) reported another patient with a clearly symptomatic form of this condition. We report a woman with late‐onset seizures occurring exclusively during tooth brushing, which were not associated with any apparent brain lesion, and responded readily to single‐drug treatment.…”