Try entering the term "paresthesia" (that's the correct spelling) into a good search engine like www.google.comIf you don't know how to do that, try this link:
http://www.ninds.nih.gov/health_and_medical/disorders/paresthesia.htm
It is a neurological disorder that resembles prolonged 'pins and needles'. As far as I know there is no strong connection between paresthesia and dystonia - this bulletin board is for spasmodic dysphonia, which is a focal dystonia that affects the larynx, producing a tight, strained or pauses in voice with breaks in words and difficulty in initiating speech.
David Barton (NZ)