Abstracts

Rationale: Todd’s paresis is a transient paralysis following a seizure and can lateralize the seizure focus in 80-90% of cases [1]. Since the original description in 1849, other types of neurological deficits have been proposed as an extension of this phenomenon, including gaze paresis, aphasia, and visuospatial neglect. Dysgeusia has rarely been reported.

Methods: We report a case of orbitofrontal epilepsy associated with postictal dysgeusia as an atypical form of Todd’s paresis.

Results: A 40-year-old man with a first generalized tonic-clonic seizure at age 27. Brain MRI revealed a right orbitofrontal pilocytic astrocytoma involving the right caudate and hypothalamus. Treated with Phenytoin, he achieved seizure freedom for 1 year. Sleep onset seizures then recurred manifesting with rhythmic circular movements of the left leg. There was no aura, but he had a prodrome presenting with intense feelings of sadness a day prior to seizures. He consistently reported postictal dysgeusia lasting 24hours, describing a chemical taste or inability to discriminate flavors, except for sweet taste, which was preserved. Habitual seizures were captured in our epilepsy unit with onset in the right fronto-temporal region. Interictal sharp waves were noted over the right temporal region as well as independently over the left fronto-temporal region. FDG-PET and neuropsychology suggested an epileptogenic zone in the right frontal region. He is medically refractory but not interested in surgery at this time.

Conclusions: A single other case of postictal dysgeusia was reported in a patient with bilateral temporal lobe epilepsy [2]. Ictal dysgeusia was previously associated with an epileptogenic zone in the insula or fronto-parietal opercula and usually with sensory manifestations, due to involvement of the secondary somatosensory area [3]. We present a first case of orbitofrontal epilepsy associated with postictal dysgeusia as a type of Todd’s phenomenon. Recent studies explain Todd’s phenomenon as a consequence of hypoperfusion of the areas implicated in the seizure [1]. Dysgeusia has no lateralizing value, but its manifestation can provide clues to brain networks involved. The presence of a tumor and results of the presurgical evaluation are highly suggestive of an epilepsy generator in the right orbitofrontal region in our case. Clinicians should consider the orbitofrontal region as a possible localization in patients presenting with postictal dysgeusia.

References:
1.Luders, H. and Noachtar, S. Todd’s paralysis and postictal aphasia. Epileptic seizures, Pathophysiology and clinical semiology. First edition. Philadelphia: Churchill Livingstone editor, 2001. 652-656.
2. Job-Chapron, A.S., Minotti, L., Hoffmann, D. and Kahane, P. 2018. SEEG in Temporal lobe Epilepsy. In: Kahane P, Lüders HO, Lhatoo SD, editors. Invasive Studies of the Human Epileptic Brain: Principles and Practice. Oxford, England, UK: Oxford University Press, pp. 277–288
3. Cascino GD, Karnes WE. Gustatory and second sensory seizures associated with lesions in the insular cortex seen on magnetic resonance imaging. J Epilepsy 1990; 3:185–7.


Funding: Please list any funding that was received in support of this abstract.: No funding.