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

Ability to recruit, enroll, and assign participants to the trial within 12 months of the trial opening.

Total number of serious adverse events associated with bilateral PNT collection and deployment to the substantia nigra. Serious adverse events will be defined as an abscess, tumor, infection of the bed of the graft, altered mental state, seizure, ankle or foot infection, wound dehiscence at the ankle incision, spread of neuropathy of the ankle or foot on the ipsilateral side of the nerve biopsy, or other event determined by the PI/investigators to be important.

Total number of adverse events experienced by participants categorized by System Organ Class and/or High Level Group Term using MedDRA v27 for designation.

Per protocol, the surgeon has two chances to successfully deploy 60% of the PNT tissue loaded in the guide-tube into the brain per hemisphere. The number of attempted deployments will be documented and if <60% of the tissue is deployed after two attempts, a failed delivery will be documented and no other attempts will be made.

Number of minutes it takes for the procedure to be completed. This will be defined by the anesthesia start time and anesthesia end time.

The number of days each participant is admitted to the inpatient hospital for the procedure and acute post-operative care.

The number of designated study visits completed compared to the total number of study visits that are scheduled to occur.

Changes in participant neuropsychological diagnoses during scheduled evaluations will be reported. e.g. No cognitive diagnosis progressing to mild neurocognitive disorder.

Participants complete a neuropsychological assessment battery that meets the MDS guidelines for determining mild cognitive impairment/mild neurocognitive disorder. Domains include attention and working memory, executive functioning, memory (verbal and visual), language, and visuospatial skills. Participants' raw scores will be converted to standardized scores based on appropriate norms (e.g., age-based norms). Participants' 12 month re-evaluation will be compared to their baseline pre-surgical assessment to determine change from baseline on each measure. A change that exceeds 1.5 standard deviation from their baseline performance will be considered notable.

Mean change in MoCA scores for participants at study visits compared to baseline by group allocation. Assessment is scored from 0-30 with a score of 26 or better indicating normal cognition. A score less than 26 indicates a cognitive deficit.

MDS-UPDRS Part I scores non-motor symptoms effecting activities of daily living in those with Parkinson's Disease. Scores range from 0-52 with higher scores indicating greater symptom severity.

MDS-UPDRS Part II scores motor symptoms effecting activities of daily living in those with Parkinson's Disease. Scores range from 0-52 with higher scores indicating greater symptom severity.

MDS-UPDRS Part III scores motor symptoms associated with Parkinson's Disease. Part III scores range from 0-132 with higher scores indicating higher symptom severity.

MDS-UPDRS Part IV scores motor complications such as fluctuations and dyskinesia's associated with anti-Parkinson's medications. Scores range from 0-24 with higher scores indicating greater severity in motor complications.

MDS-UMSARS Part I rates patient reported functional disabilities. Scores for this section range from 0-48 with higher scores indicating greater disability

MDS-UMSARS Part II scores motor symptoms associated with multiple system atrophy. Scores range from 0-56 with higher scores indicating greater symptom severity.

MDS-UMSARS Part III assesses orthostatic hypertension symptoms. This part examines blood pressure changes when a participant stands up after laying down for two minutes. It is scored as either a "Yes" the participant experiences orthostatic hypertension, or a "No" the participant does not don't experience orthostatic hypertension.

MDS-UMSARS Part IV assess the participants global disability. Scores range from 1-5 with 1 being completely independent and 5 being totally dependent/bedridden.

Assess changes in participant's quality of life. Questionnaire is scored from 0-32 with higher scores indicating poorer quality of life.

Mean change participant independence levels as measured in Schwab and England Scale of Activities of Daily Living scores. 100% = completed independent and 0% being completely dependent.

Assessment used to identify Parkinson's disease related non-motor symptoms experienced by participants. The scale measures the frequency and severity of symptoms and is scored from 0-360 with higher scores indicating more frequent and severe symptoms.

Number of study participants who elect to have DBS implanted prior to completing the 12 month study visit.