This study is tracking people who had a procedure using the Exablate 4000 machine to help with their Parkinson's Disease, a condition affecting movement. The procedure is called unilateral pallidotomy, which means treating one side of the brain to improve movement problems when medicines don't help enough. The study will follow participants for 5 years, checking in at 3, 6, and 12 months, then once a year.

Participants will be asked about any side effects, how much medicine they take, and how their symptoms change. The study will also see how satisfied they are with the treatment. People who can join are men and women who are 30 years or older and have had this procedure.

• The study lasts for 5 years with several check-ins.
• Participants need to visit about 10 centers worldwide for follow-ups.
• Participants must be willing to follow the study rules and attend all visits.