Focused ultrasound therapy in movement disorders: management roadmap toward optimal pathway organization.

MRI-guided focused ultrasound (MRgFUS) lesioning is an innovative, safe and effective treatment which provides an innovative development in the field of minimally invasive stereotactic neurosurgery. Based on the application of focused ultrasound energy under full MR planning and thermal imaging control, unilateral lesioning of the thalamus, subthalamic nucleus, and globus pallidus is indicated for the treatment of movement disorders, including essential tremor, Parkinson's disease, and dystonia. We started to apply this technique in February 2019 for the treatment of patients with movement disorders. The authors developed a diagnostic therapeutic care pathway, which is herewith proposed and applied as an explication of standard clinical practice in use. The project was the result of the application of different methods such as Health Technology Assessment (HTA), Strengths, Weaknesses, Opportunities and Threats analysis (SWOT) and Demin -Plan, Do, Check, Act (PDCA) cycle. The aim of this project was to standardize the MRgFUS diagnostic-therapeutic pathway (DTP), describe its application and the appropriateness of different phases (patient selection, intervention phase and follow-up). Here, we described in detail our experience in the DTP application from 2019 up to now in 610 patients with movement disorders.

Bilateral Simultaneous Magnetic Resonance-Guided Focused Ultrasound Pallidotomy for Life-Threatening Status Dystonicus.

BACKGROUND: Invasive treatments like radiofrequency stereotactic lesioning or deep brain stimulation of the globus pallidus internus can resolve drug-resistant status dystonicus (SD). However, these open procedures are not always feasible in patients with SD. OBJECTIVE: The aim was to report the safety and efficacy of simultaneous asleep bilateral transcranial magnetic resonance-guided focused ultrasound (MRgFUS) pallidotomy for life-threatening SD. METHODS: We performed bilateral simultaneous MRgFUS pallidotomy under general anesthesia in 2 young patients with pantothenate kinase-associated neurodegeneration and GNAO1 encephalopathy. Both patients had medically refractory SD and severe comorbidities contraindicating open surgery. RESULTS: SD resolved at 4 and 12 days after MRgFUS, respectively. Adverse events (intraoperative hypothermia and postoperative facial paralysis) were mild and transient. CONCLUSION: Bilateral simultaneous MRgFUS pallidotomy under general anesthesia is safe and may be a valid alternative therapeutic option for fragile patients. Further studies are needed to assess long-term efficacy of the procedure. © 2024 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

The Optimal Targeting for Focused Ultrasound Thalamotomy Differs between Dystonic and Essential Tremor: A 12-Month Prospective Pilot Study.

BACKGROUND: Magnetic resonance-guided focused ultrasound (MRgFUS) thalamotomy is increasingly used to treat drug-resistant essential tremor (ET). Data on MRgFUS thalamotomy in dystonic tremor (DT) are anecdotal. OBJECTIVES: To investigate efficacy, safety, and differences in target coordinates of MRgFUS thalamotomy in DT versus ET. METHODS: Ten patients with DT and 35 with ET who consecutively underwent MRgFUS thalamotomy were followed for 12 months. Although in both groups the initial surgical planning coordinates corresponded to the ventralis intermediate (Vim), the final target could be modified intraoperatively based on clinical response. RESULTS: Tremor significantly improved in both groups. The thalamic lesion was significantly more anterior in DT than ET. Considering both ET and DT groups, the more anterior the lesion, the lower the odds ratio for adverse events. CONCLUSIONS: MRgFUS thalamotomy is safe and effective in DT and ET. Compared to classical Vim coordinates used for ET, more anterior targeting should be considered for DT.