Parkinson’s disease (PD) is the second most common neurodegenerative disease in the world. High-intensity focused ultrasound (HIFU) is a new non-invasive therapeutic option for treating the motor symptoms of PD. HIFU is an imaging-guided procedure for therapeutic brain ablation that has been used for patients with essential tremor and neuropathic pain. It is indicated for patients older than 22 years of age who have PD that is refractory to drug treatment and are ineligible for surgery. The objective of this study was to conduct an early assessment of HIFU subthalamotomy for the treatment of motor symptoms in patients with PD.

HIFU was identified by the early awareness and alert system, SINTESIS- nuevas tecnologías, of the Agencia de Evaluación de Tecnologías Sanitarias at the Instituto de Salud Carlos III. Relevant literature published to October 2021 was identified by searching PubMed, EMBASE, ClinicalTrials.gov, and the Cochrane Library.

One prospective study and one randomized controlled trial (RCT) were found that assessed the efficacy and safety of HIFU subthalamotomy for treating the motor symptoms of PD. The Movement Disorder Society-Sponsored Revision of the Unified Parkinson’s Disease Rating Scale Part III (MDS-UPDRS III) was used to measure changes in symptoms (>30% change from baseline was considered clinically relevant). Both studies reported a reduction of symptoms in the intervention group. The MDS-UPDRS III score changed from 16.6 to 7.5 six months after treatment in the prospective study and from 19.9 to 9.9 four months after treatment in the RCT (a decrease of 11.6 points was observed after 12 months). The main adverse events reported were dyskinesia, speech and gait disturbances, and weakness, all of which resolved without treatment.

The results regarding the efficacy and safety of HIFU for treating the motor symptoms of PD are promising. HIFU is a non-invasive procedure that eliminates the risks associated with surgery. Although rapid diffusion of this technology is expected, further studies and economic evaluation are needed.