Autologous suraL nervE Grafting to the Substantia nigrA in Patients With Synuclienopathies

This phase I double-blind study focuses on the safety and feasibility of implanting autologous peripheral nerve tissue (PNT) into the substantia nigra area of the brain in persons who have been diagnosed with either Parkinson's disease (PD) or Multiple System Atrophy (MSA). 7 participants will be enrolled, with 4 participants receiving the graft and 3 receiving a sham surgery. Eligible participants will be early in their diagnosis with a lower burden of symptoms. Participants will be followed initially for one year after surgery.