Incidence of RINCH in pediatric EMU patients.

Abstract

RINCH (Rhythmic Ictal Non-Clonic Hand movements), a lateralizing sign in frontotemporal epilepsy, has been well described in the adult epilepsy population but not in the pediatric setting. We looked for evidence of RINCH as an ictal sign in pediatric epilepsy monitoring unit reports in a large academic pediatric hospital. We found nine patients with RINCH ictal phenomenon over a five-year period. We compared the characteristics of their epilepsy to the known data in adult patients. The patient age range was 6-15 years. Five patients had a lesion in the temporal lobe; the remaining four were non-lesional. The ictal EEG onset was in one temporal lobe in five patients. The remaining patients had frontal or non-localizable onset. However, ictal activity was present in the frontal lobe(s) in six patients at the time of RINCH. Seven occurrences of RINCH were contralateral to the epileptogenic lesion and/or ictal scalp EEG activity. The remaining patients were non-lesional with bilateral frontotemporal ictal activity. Dystonia was ipsilateral to the RINCH in two patients. This study reinforces the lateralizing significance of RINCH as an ictal phenomenon when it is present. RINCH may be rare in the pediatric epilepsy population, but it may also be under-reported.