Factors Determining the Efficacy of Botulinum Toxin for Arm Tremor in Dystonia

Summary

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.

Conditions

• Dystonic Tremor Syndrome

Interventions

DIAGNOSTIC_TEST

Polymyography

We will measure muscle activity using surface electromyography and tremor using inertial measurement units while subjects perform rest, posturing and kinetic tasks.

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Muscle ultrasound

We will obtain B-mode images and videos of upper extremity muscles of the most affected upper extremity.

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(Functional) magnetic resonance imaging

Subjects will undergo (f)MRI scanning involving concurrent electromyography, accelerometry and functional magnetic resonance imaging.

DIAGNOSTIC_TEST

Clinical assessment

We will assess tremor and dystonia severity using clinical scales.

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Questionnaires

We will collect patient-reported outcomes.

DRUG

botulinum toxin injection (BTX A)

Three consequetive botulinum toxin injections of the upper extremities

Sponsors & Collaborators

• Canisius-Wilhelmina Hospital

  collaborator OTHER

• Donders Centre for Cognitive Neuroimaging

  collaborator OTHER

• Radboud University Medical Center

  lead OTHER

Principal Investigators

• Anke Snijders, PhD · Radboud University Medical Center

Study Design

Allocation

NA

Purpose

TREATMENT

Masking

NONE

Model

SINGLE_GROUP

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2025-01-01

Primary Completion

2027-05-30

Completion

2027-05-30

Countries

• Netherlands

Study Locations