Purpose: The aim of our work was to describe the initial electroencephalographic characteristics of Rasmussen's syndrome (RS).
Methods: We performed repeated EEG recordings in an 11-year 5-month-old girl affected by RS, as demonstrated through the progressive evolution of the illness. All EEGs were carried out in polygraphy and videorecordered, both in waking and in sleep.
Results: In our opinion, our patient's EEG picture is absolutely unusual in childhood partial epilepsy form without any neuroradiologic perturbation. Delta focal activity persistence in such a clinical context should be considered an RS sign, among the possible causes.
Conclusions: We are not aware of any early-stage RS EEG description. We think that the initial RS EEG picture is so unusual as to suggest such pathology. We hope that analogous reports can confirm our belief.