Extrapyramidal disturbances after cyanide poisoning (first MRT-investigation of the brain)

A 29 year old student of chemistry took 50 ml of a 1% potassium cyanide solution (500 mg) in attempted suicide. He became comatose, mydriatic and was admitted to hospital in an apneic state. He woke up after seven hours and developed Parkinsonism in the following weeks. This regressed slowly in the second month after the poisoning apart from dysarthria, bradykinesia of the upper limbs and very brisk monosynaptic reflexes. Three weeks after the intoxication, CCT was largely normal, and there was CSF-dense hypodensity in both putamina after five months. Sharply delimited signal elevation in T2 corresponding to the two putamina was detected in the MRI eight weeks and five months after ingestion of the poison.