Category: Parkinson’s Disease: Clinical Trials
Objective: To evaluate the safety, efficacy, and patient-reported outcomes of unilateral MRgFUS pallidothalamic tractotomy (PTT) for the treatment of aPD.
Background: In July 2025, the FDA approved staged bilateral MRgFUS pallidothalamic tractotomy (PTT) for advanced Parkinson disease (aPD), allowing a contralateral procedure ≥6 months after the first. We report comprehensive patient‑reported outcomes after unilateral PTT to inform risk–benefit discussions.
Method: Fifty‑four patients underwent unilateral MRgFUS PTT in a multicenter trial. Visits: baseline, W1, M1/M3/M6. Month‑6 outcomes: MDS‑UPDRS II/III (OFF)/IV, PGIC/CGIC, satisfaction, and related AEs.
Results: At 3 months post‑unilateral treatment, MDS‑UPDRS Part III Total (OFF) improved by 32% (baseline 51.4 ± 12.7 SD; 3‑month 12.1 ± 6.3 SD), Part IV improved by 56% (baseline 10.5 ± 3.5 SD; 3‑month 4.6 ± 3.7 SD), and Part II improved by 27% (baseline 16.7 ± 8.0 SD; 3‑month 12.1 ± 6.3 SD). 94% of participants rated themselves as having at least some improvement, with 72% considering their condition to be much or very much improved. 93% (50/54) of participants responded that, taking everything into account, they would have the procedure again. 85% (46/54) felt satisfied that the good things outweighed the bad, 85% (46/54) were overall satisfied with the procedure, 85% (46/54) felt that the procedure reduced their PD symptoms well on one side, and 28% (15/54) felt that their PD symptoms were reduced on both sides. According to clinician ratings, 98% of participants showed at least some improvement, with more than 80% being rated as much or very much improved. Thirty related AEs occurred in 21 participants (87% mild), with none being severe. At 6 months, there was only one ongoing clinically significant (moderate) event (dyskinesia on the treated side).
Conclusion: Unilateral MRgFUS PTT produced clinically meaningful improvements in motor severity (Part III), motor complications (Part IV), and motor experiences of daily living (Part II) at 3 months, with high concordant patient and clinician‑rated benefit. The safety profile was favorable (87% mild; no severe AEs), supporting a favorable risk–benefit balance for candidates with aPD.
To cite this abstract in AMA style:
H. Sarva, K. Gant, C. Modak, C. Ferrer, A. Sokolov, A. Grinspan. Outcomes from Unilateral MR-Guided Focused Ultrasound Pallidothalamic Tractotomy for Advanced Parkinson’s Disease [abstract]. Mov Disord. 2026; 41 (suppl 1). https://www.mdsabstracts.org/abstract/outcomes-from-unilateral-mr-guided-focused-ultrasound-pallidothalamic-tractotomy-for-advanced-parkinsons-disease/. Accessed October 1, 2026.« Back to 2026 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/outcomes-from-unilateral-mr-guided-focused-ultrasound-pallidothalamic-tractotomy-for-advanced-parkinsons-disease/
