Gelastic seizures in ring chromosome 20 syndrome: a case report with video illustration

Although increasingly recognised, ring chromosome 20 (r[20]) syndrome is still diagnosed with delay, sometimes leading to inappropriate presurgical evaluation. The focal, presumed frontal, character of the seizures manifesting with fear and hypermotor behaviour and episodes of non-convulsive status epilepticus (NCSE) are most typical, as well as cognitive impairment with behavioural problems and, sometimes, dysmorphic signs. We present a girl diagnosed at the age of 13 years who suffered from an atypical clinical presentation, with minimal cognitive problems, absence of dysmorphic symptoms, and hypermotor/gelastic seizures.