Abstracts

Rationale: In 1901 Sir William Gowers was the first to report auditory auras in 7% of 1100 patients with focal epilepsy. Subsequent studies have suggested a higher incidence in temporal compared to extratemporal epilepsies. Ictal auditory symptoms described range from elemental sounds to complex musical tunes. As musical auras (MA) are rare we studied 15 patients who reported MA and had a complete presurgical evaluation to understand the functional anatomy of MA. Methods: We retrospectively identified 30 patients with auditory auras in our database from 1990 to 2008. The surface EEG, MRI and outcome of 15 patients who had MA were analysed further. Results: Nine women and six men (37 ± 15 years) with a mean duration of epilepsy of 10 ±13 years reported experiencing persistent MA at the onset of their seizures. The average age of onset was 28 ± 17 years, the average seizure frequency was 10 ± 13 per month. The tunes of the MA consisted of recognizable melodies from popular music, (e.g. Michael Jackson song, an advertisement jingle). One patient had MA early in the epilepsy course but then lost the memory of the MA. An additional epigastric aura was reported by 5 patients suggesting limbic localization. No vertigo or visual symptoms were reported. The MA was followed by a complex partial seizure with secondary generalization in most. Neuroimaging was obtained in 12 patients, all lesions were found in the dominant temporal or temporoparietal region - neoplasms in 3, of which 2 were inoperable, mesial temporal sclerosis in 2, unidentified mass on MRI in 2, arteriovenous malformation in 1 malformation of cortical development in 1, herpes encephalitis in 1 and remote head trauma in 1. The remaining patients had a cryptogenic etiology. Four patients had resective epilepsy surgery with improved seizure control but no seizure freedom (all Engel IIc) and 4 patients remitted on AEDs and did not require ES. Conclusions: Our series of 15 patients with MA supports the notion that the cortical network subserving melody may be activated in patient with dominant temporal lobe epilepsy. Lesional etiologies were common and ameanable to surgery in some cases but without a high prospect of seizure free outcome. This may imply that a more extensive epileptogenic network that is not completely resectable needs to be activated to produce MA. This will be illustrated with the findings of a patient who underwent invasive EEG recording.