Rationale The internal globus pallidus can be regarded as an "output structure" of the basal ganglia. It processes input from nucleus accumbens and the striatum, and sends input to the cerebral cortex via the thalamus. It is critical for the functioning of the basal ganglia. Parkinson's disease<unk>  is an alternative to deep brain stimulation for the treatment of the involuntary movements known as dyskinesias which can become a problem in people with Parkinson's disease after long-term treatment with levodopa — a condition known as levodopa-induced dyskinesia. Whilst it used to be used a primary treatment for Parkinson's disease, it has been mainly replaced by levodopa. Other conditions<unk>  may sometimes used to treat difficult cases of essential tremor as an alternative to deep brain stimulation. It may also be used for dystonia, and hemiballismus.
Pallidotomy
Cricopharyngeal myotomy
Ventriculotomy 
Lumbar–peritoneal shunt
Surgical airway management
Positive airway pressure
Cerebrospinal fluid diversion
Craniotomy