Dr. Pedro Roldán Ramos
Neurosurgeon · Functional surgery, DBS and HIFU · Professor at the UB
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Focused ultrasound · no incisions
HIFU for Parkinson's disease: tremor treatment without opening the skull
HIFU is the clinical term for high-intensity focused ultrasound guided by magnetic resonance imaging (HIFU / MRgFUS). In tremor-dominant Parkinson's disease, it creates a millimetric thermal lesion in the Vim nucleus of the thalamus to abolish tremor. No incisions, no general anaesthesia, same-day discharge, and immediate improvement.
What is it?
HIFU: focused ultrasound to abolish Parkinson's tremor
HIFU is the clinical term for high-intensity focused ultrasound guided by magnetic resonance imaging (HIFU / MRgFUS). It is an ablative neurosurgical technique that requires no incisions, no skull opening, and no general anaesthesia. Ultrasound waves pass through the intact skull and converge with sub-millimetre precision on the Vim nucleus of the thalamus, where they generate a controlled thermal lesion that interrupts the circuit responsible for parkinsonian tremor.
0
incisions · skull remains intact throughout the treatment
Outpatient
single session · same-day hospital discharge
Immediate
tremor improvement is felt in the operating theatre
"MRI-guided focused ultrasound is an effective and safe therapeutic option for refractory tremor-dominant Parkinson's disease, with the advantage of requiring no incisions, implants, or general anaesthesia."
What sets HIFU apart from other options
- No incisions or craniotomy. The skull remains intact throughout the procedure.
- No general anaesthesia. The patient is awake and cooperates with the team.
- No implants or batteries. There is no subcutaneous generator to maintain or replace.
- Immediate effect. Unlike gamma knife radiosurgery, tremor improvement appears in the same surgical session.
- Same-day discharge. Immediate recovery with no hospitalisation required.
- Clinically approved by the FDA (tremor-dominant Parkinson's disease, 2018) and CE-marked in Europe.
How it works
HIFU treatment for Parkinson's disease · step by step
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1 · Multidisciplinary assessment
Joint assessment with neurology. Confirmation of the diagnosis of tremor-dominant Parkinson's disease (tremor predominant over rigidity and bradykinesia), MDS-UPDRS-III scale, levodopa test, cognitive assessment, and brain MRI compatible with the HIFU system.
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2 · Preparation on the day of treatment
Complete head shaving (required for uniform transducer contact with the scalp), placement of the stereotactic frame under local anaesthesia, and fixation to the MRI system. The patient is awake and cooperates throughout the procedure.
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3 · Target localisation
MRI images are acquired to precisely identify the Vim nucleus of the thalamus on the side contralateral to the tremor to be treated. The trajectory of ultrasound beams through the patient's skull is calculated.
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4 · Test sonications (low power)
Low-energy ultrasound pulses that mildly heat the target without causing a lesion. The patient's clinical response is evaluated in real time (handwriting, arm reach, balance). If there is tremor improvement without adverse effects, the target is confirmed. If unwanted effects occur, the target is repositioned before the definitive lesion.
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5 · Therapeutic sonications (high power)
Energy is gradually increased until the definitive thermal lesion is created (55-60 °C at the focus). The patient confirms persistent tremor improvement and the absence of adverse effects at each increment.
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6 · Observation and discharge
2-4 hours in the recovery room to verify neurological stability, removal of the stereotactic frame, and a control MRI. Same-day discharge with tremor improvement already established.
HIFU vs DBS for Parkinson's disease
DBS implants electrodes in the brain and a subcutaneous pulse generator; it is reversible, adjustable, and bilateral. HIFU creates a permanent thermal lesion without implanting anything; it is ablative, unilateral, and leaves no foreign material in the body. HIFU is preferable for older patients, those with contraindications to open surgery, patients on anticoagulation, or those who decline an implant. DBS is preferable when bilateral modulation or fine adjustment over time is required. See DBS for Parkinson's disease →
Symptoms and indications
When is HIFU indicated for Parkinson's disease?
HIFU is indicated in patients with tremor-dominant Parkinson's disease and disabling tremor refractory to medication. The clinical indication requires meeting several criteria simultaneously:
Clinical criteria
- Confirmed diagnosis of idiopathic Parkinson's disease.
- Tremor-dominant presentation (tremor predominant over rigidity and bradykinesia).
- Resting tremor that is unilateral or clearly asymmetric.
- Partial or no tremor response to levodopa at optimal doses.
- Documented functional impact: the person cannot write, eat with a spoon, drink from a glass, or perform basic activities independently.
- Age and comorbidities that advise against or complicate DBS.
- Chronic anticoagulation that contraindicates electrode implantation.
- Patient's personal preference for a technique without an implant.
Technical criteria (system compatibility)
- Compatible brain MRI (no severe claustrophobia, no incompatible cardiac pacemaker).
- Adequate skull bone density for ultrasound transmission (SDR index 0.40 or above measured on prior cranial CT).
- Good cognitive status and ability to cooperate throughout the procedure.
- Ability to remain still during MRI sessions.
When HIFU is NOT indicated
Patients with rigidity/bradykinesia-dominant Parkinson's disease, significant cognitive decline, incompatible skull anatomy (SDR < 0.40), cardiac pacemaker incompatible with MRI, severe claustrophobia, or immediate bilateral need (in this last case DBS is usually preferred).
Results
What results to expect
Published clinical series in tremor-dominant Parkinson's disease treated with HIFU/MRgFUS show:
- 60-75% reduction in tremor on the contralateral side to the treated hemisphere, immediately after the procedure.
- Sustained improvement in more than 50% of patients at 5 years of follow-up.
- Immediate functional recovery: handwriting, eating with a spoon, independence in basic activities on leaving hospital.
- Same-day discharge with no hospitalisation required.
- No subsequent surgical revisions needed (no battery to replace).
Possible side effects include transient paraesthesias, balance disturbance, or mild dysarthria, generally reversible within the first weeks. Rigorous patient selection and planning with test sonications minimises these events.
Frequently asked questions
Answers to your questions
What is HIFU applied to Parkinson's disease?
HIFU is treatment by high-intensity focused ultrasound guided by magnetic resonance imaging (HIFU / MRgFUS). In Parkinson's disease, ultrasound waves converge on the Vim nucleus of the thalamus and create a millimetric thermal lesion that abolishes the circuit responsible for tremor. No incisions, no general anaesthesia, same-day discharge.
Which Parkinson's disease patients are candidates for HIFU?
Patients with tremor-dominant Parkinson's disease (resting tremor that is unilateral or clearly asymmetric, predominant over rigidity and bradykinesia), with partial or no tremor response to levodopa, without significant cognitive decline, and who decline or have a contraindication to electrode implantation (DBS). The indication is confirmed after multidisciplinary assessment and CT to measure the SDR skull index.
Does HIFU cure Parkinson's disease?
No. HIFU does not cure Parkinson's disease or halt its progression. It specifically treats tremor: it reduces or eliminates tremor on the contralateral side in approximately 60-75% of patients. Bradykinesia, rigidity, and non-motor symptoms still require ongoing medical treatment from the neurologist.
How does HIFU differ from DBS for Parkinson's disease?
HIFU creates a permanent thermal lesion without implanting anything; it is ablative, unilateral, without incisions, with same-day discharge. DBS implants electrodes in the brain connected to a subcutaneous pulse generator; it is reversible, adjustable, bilateral, and reprogrammable. HIFU is preferable for older patients or those with contraindications. DBS is preferable when bilateral modulation or fine adjustment over time is required. See DBS →
How quickly does HIFU take effect?
The effect is immediate. Unlike gamma knife radiosurgery (which takes weeks or months to produce its biological effect), HIFU generates a controlled thermal lesion in the same surgical session. The patient notices tremor improvement on leaving the operating theatre and results are confirmed at the time of discharge.
Can HIFU be performed bilaterally?
For the time being the standard indication is unilateral (one side of the body per session). Bilateral treatment is under study in research protocols but is not established clinical practice outside trials. For bilateral indications, DBS is usually preferred.
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Team
Functional neurosurgery and movement disorder neurology
The management of Parkinson's disease, tremor and movement disorders combines functional surgery (HIFU, DBS) with specialist movement disorder neurology assessment, both before and after the procedure.
Dr. Gabriel Salazar Tortolero
Neurologist · Parkinson's disease, tremor and movement disorders
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Locations
Where we treat HIFU for Parkinson's disease
Surgical procedures are carried out in operating theatres equipped with the technology required for HIFU for Parkinson's disease. Your first consultation and follow-up can take place at any of our centres in Barcelona.
Operating theatre
★ Operating theatre
Hospital El Pilar
★ Operating theatre
Barnaclínic+
Consultation and follow-up
Consultation
Centro Médico Aribau
Consultation
Clínica Olivé Gumà
Patient reviews
What our patients say
High-grade glioma
"I arrived with a glioma I had been told was inoperable. Here they reviewed it at the tumour board and offered me a plan. The surgery was a success. Four years on, I am well."
Cervical disc herniation
"For years I had a cervical disc herniation, operated on by another team with no improvement. Minimally invasive surgery gave me back my mobility and took the pain away."
International patient
"I travelled from outside Spain. The team reviewed my case before I came and gave me a clear plan. Caring people and impeccable technique."
Request information
Are you a candidate for HIFU for Parkinson's disease?
Send us the neurologist reports, the brain MRI, and the cranial CT (to measure the SDR index). We evaluate your case in a multidisciplinary committee within 24-48 hours and advise whether HIFU is the best option for your specific clinical situation.