Eficacia y Seguridad de la Tractotomía Pálido-Talámica mediante  Ultrasonido Focalizado Guiado por Resonancia Magnética en la Enfermedad de Parkinson: Una Revisión Sistemática

Francisco Rivera; Nelson Ernesto Quintanal Cordero; Camila Casal; Fabián Piedimonte

doi:10.47924/neurotarget2026607

Authors

Francisco Rivera Fundación CENIT para la Investigación en Neurociencias, Buenos Aires, Argentina. https://orcid.org/0009-0005-8979-1906
Nelson Ernesto Quintanal Cordero Fundación CENIT para la Investigación en Neurociencias, Buenos Aires, Argentina. https://orcid.org/0000-0003-3812-5899
Camila Casal Fundación CENIT para la Investigación en Neurociencias, Buenos Aires, Argentina. https://orcid.org/0009-0001-9509-1341
Fabián Piedimonte Fundación CENIT para la Investigación en Neurociencias, Buenos Aires, Argentina. https://orcid.org/0000-0003-4661-4449

DOI:

https://doi.org/10.47924/neurotarget2026607

Keywords:

Parkinson’s disease, MRgFUS, pallidothalamic tract, tractotomy, functional neurosurgery, dyskinesia, bradykinesia

Abstract

Background: Pallidothalamic tractotomy using magnetic resonance-guided focused ultrasound (MRgFUS-PTT) has emerged as a minimally invasive ablative option for treating refractory motor symptoms in Parkinson’s disease (PD), particularly rigidity, distal bradykinesia, and levodopa-induced dyskinesias.
Methods: A systematic review was conducted according to PRISMA guidelines, searching PubMed/MEDLINE and Scopus from january 2010 to december 2025. Clinical studies evaluating MRgFUS targeting the pallidothalamic tract (PTT) in PD patients were included. Eligible studies reported efficacy outcomes, safety data, and relevant technical parameters, with at least three patients and a minimum follow-up of one month.
Results: Five studies including 99 patients were analyzed. MRgFUS-PTT demonstrated clinically meaningful reductions in tremor (up to 84%), rigidity (up to 70%), and distal bradykinesia (up to 73%) on the treated side. Significant reductions in levodopa-induced dyskinesias and dopaminergic medication dosage were also reported. MDS-UPDRS III scores improved significantly in both “on” and “off” medication states. Adverse events were predominantly mild or transient, including headache, mild dysarthria, and speech disturbances, with one reported case of permanent freezing of gait. Technical parameters commonly included focal temperatures above 50–55 °C and cumulative thermal doses ≥240 cumulative equivalent minutes per focal point (≥240 CEM43°C per focal point).
Discussion: MRI-guided focused ultrasound-guided pallidal tractotomy represents an approach targeting a key outflow tract of the pallidal system, differing from classic nuclear targets such as the ventral intermediate nucleus of the thalamus, the subthalamic nucleus, and the and the internal globus pallidus.. Available results suggest a symptomatic improvement profile that could position it as a complementary alternative within the functional ablation spectrum. However, methodological heterogeneity, small sample size, and limited follow-up prevent definitive conclusions regarding its durability and superiority over other techniques.
Conclusions: MRgFUS pallidothalamic tractotomy demonstrates significant clinical efficacy in selected motor symptoms of PD, with an overall favorable safety profile in specialized series. However, limited sample sizes, methodological heterogeneity, and short follow-up periods underscore the need for prospective multicenter trials to define its definitive role within the functional surgical armamentarium for PD.

Keywords: Parkinson’s disease, MRgFUS, pallidothalamic tract, tractotomy, functional neurosurgery, dyskinesia, bradykinesia.

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