Abstract
Objectives We present a case of a toothbrushing epilepsy, a rare form of reflex epilepsy, where seizures are reliably induced by toothbrushing. Ictal functional MRI (fMRI) and Stereoelectroencephography (sEEG) were used to localise the seizure onset zone and following highly localised radiofrequency thermocoagulation the patient was rendered seizure free.
Method Case Report
Results A 22-year-old female patient had drug-resistant toothbrushing-induced focal motor seizures since age 14. Seizures manifested as daily episodes of right facial dystonia, with additional triggers including eating, talking and strenuous exercise. Ictal Scalp EEG demonstrated low voltage fast activity over the left pericentral area. Structural MRI imaging did not reveal a definite epileptogenic lesion. fMRI of a toothbrushing induced seizure highlighted a region in the low pericentral area with an unusual but not definitively abnormal anatomical arrangement. sEEG in this area demonstrated frequent focal spikes and sharp waves (irritative zone). Radiofrequency thermocoagulation to this area was performed and the patient has remained seizure free for more than two years.
Conclusion In reflex epilepsy, the seizure precipitants highlight the likely seizure onset zone. Functional MRI can provide further localising information to more precisely guide the implantation of intracranial sEEG electrodes. Interestingly, ictal fMRI revealed the local seizure network, which was immediately adjacent to the irritative zone, in the depths of the central sulcus. Highly focal thermocoagulation can render patients seizure free if the seizure focus can be accurately defined.
