[Nocturnal paroxysmal dystonia, movement disorder and epilepsy]

Nocturnal paroxysmal dystonia (NPD) is a disorder which appears during sleep. It is characterized by generally brief paroxysmal motor events which are complex when clinically expressed and are often repetitive. The origin of this disorder has been a matter for discussion for some time. Initially it was considered a specific movement disorder, but recently it has been suggested that it is epileptic in nature.

In this study we present the case of a patient who is hospitalized in the Unit for epileptic surgery, suffering from epilepsy which does not respond to medical treatment and requires surgery. The patient is treated with conventional methodology, prolonged and continuous presurgical videoelectroencephalographic monitoring. EEG registers were used via electrodes placed in the scalp and skull, electrodes placed in the skull on adequate indication. Two types of perfectly defined electroclinical events occurred: some not epileptic and others clearly epileptic. On one occasion a convulsive tonic clonic epileptic crisis was recorded typical of frontal focal origin preceded by non epileptic motor phenomena.

The presence of paroxysmal motor episodes during sleep, atypical as a form of epilepsy, the absence of unquestionable specific data in the EEG, and in the light of our discoveries, force us to consider the possibility that NPD is in fact a form of epilepsy caused in a reflex manner by a specific type of movement disorder during sleep, and whose origin should be more widely discussed.