Continuous Electrical Neuromodulation of the Globus Pallidus Intern in Parkinson's Disease by the Directional Electrode CARTESIA™

This study is testing a directional deep brain stimulation (DBS) device called CARTESIA to treat Parkinson's disease. DBS involves surgically implanting a small device that delivers electrical pulses to a specific area deep in the brain, helping control movement symptoms like tremor, stiffness, and slowness. **You may be eligible if...** - You have a diagnosis of bilateral idiopathic Parkinson's disease that has been progressing for more than 4 years - Your symptoms still respond well to levodopa (L-Dopa) medication, with at least 30% improvement on a standard motor scale - You have significant motor problems such as prolonged freezing episodes, fluctuating symptoms, or disabling tremor that is not adequately controlled by medication - Your general health allows you to undergo surgery and general anesthesia **You may NOT be eligible if...** - You have significant depression, psychosis, or dementia - You have a pacemaker, cochlear implant, or other device that is incompatible with MRI - You have metal implants in the brain or contraindications to surgery - You are pregnant Talk to your doctor to see if this trial is right for you.