People with tremor disorder  are being treated in an experimental procedure pioneered by Toronto scientists.

In the non-invasive operation , doctors use high-intensity ultrasound waves to punch a tiny hole in the part of the brain where the tremor originates.

The procedure was performed on a fifth patient at Sunnybrook Health Sciences Centre yesterday.

Doctor Michael Schwartz is head of neurosurgery at Sunnybrook.

He says the first phase of his study will involve six patients with severe essential tremor.

The disorder is not the same as Parkinson’s disease ..  although both are marked by uncontrolled shaking in the extremities, mainly in the arms and hands.