Factors Determining the Efficacy of Botulinum Toxin for Arm Tremor in Dystonia
Key facts
- Phase
- Phase 4
This trial has no sites in United States.
It has sites in one country. Choose a country to see its sites.
Trial details
- Who runs it
- Radboud University Medical Center
- Trial code
- NCT06411028
- Record updated
- 14 August 2026
- Original description
Tremor occurs in up to 55% of dystonia patients, which is known as dystonic tremor syndrome (DTS). Tremor can be present in the body part affected by dystonia (dystonic tremor, DT), or an unaffected body part (tremor associated with dystonia, TAWD). DTS can be treated with botulinum neurotoxin (BoNT) injections, but BoNT is effective in only about 60-70% of patients. It is unknown which patients benefit most from BoNT treatment. The investigators aim to explore the associations between clinical and pathophysiological tremor characteristics and BoNT efficacy. To do so, the investigatorswill measure clinical, electrophysiological, ultrasonographic and (functional) magnetic resonance imaging ((f)MRI) characteristics before the start of BoNT treatment and measure BoNT efficacy after three three-monthly BoNT sessions.Read full original descriptionShow less
Factors Determining the Efficacy of Botulinum Toxin for Arm Tremor in Dystonia: An Exploratory Study
Tremor occurs in up to 55% of dystonia patients, which is known as dystonic tremor syndrome (DTS). Tremor can be present in the body part affected by dystonia (dystonic tremor, DT), or an unaffected body part (tremor associated with dystonia, TAWD). DTS can be treated with botulinum neurotoxin (BoNT) injections, but BoNT is effective in only about 60-70% of patients. It is unknown which patients benefit most from BoNT treatment. The investigators aim to explore the associations between clinical and pathophysiological tremor characteristics and BoNT efficacy. To do so, the investigatorswill measure clinical, electrophysiological, ultrasonographic and (functional) magnetic resonance imaging ((f)MRI) characteristics before the start of BoNT treatment and measure BoNT efficacy after three three-monthly BoNT sessions.
Inclusion: Clinical diagnosis of dystonic tremor or tremor associated with dystonia according to the 2018 consensus statement on the classification of tremors; Tremor of one or both upper extremities; Starting botulinum toxin injections as part of normal clinical practice; Age ≥ 18 years.
Exclusion: Previous botulinum toxin treatment of the to be treated upper extremity for ≥ 4 consecutive sessions; In case of previous botulinum toxin treatment of the to be treated upper extremity for ≤3 consecutive sessions: the last botulinum toxin injections ≤ 6 months before study enrolment; Unstable dose medications for dystonia and tremor ≤ 1 month before study enrolment; Deep brain stimulation implantation ≤ 6 months before study enrolment; Unstable deep brain stimulation variables ≤ 1 month before study enrolment; Contraindications for MRI (e.g. previous brain surgery, claustrophobia, active implant, epilepsy, metal objects in the upper body that are incompatible with MRI); Acquired aetiology of dystonic tremor syndrome; Known hypersensitivity for components of Dysport; Infection at the upper extremity; Comorbidity interfering with study participation; Pregnancy, trying to conceive and breastfeeding; Insufficient knowledge of the Dutch or English language; Moderate to severe head tremor while lying supine (to avoid artefacts caused by extensive head motion during scanning); Inability to provoke postural tremor while lying supine.