Alteration of Deep Brain Stimulation Parameters for Dystonia

NCT00971854 | Unknown DMC

• 2 other identifiers: 09/H0603/11R&D Study - 5898
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

Deep brain stimulation (DBS) involves placing electrodes into the brain. Through these electrodes, artificial electrical signals are chronically delivered into deep brain regions in order to alter abnormal brain activity. The artificial electrical signals are generated by a battery that is inserted under the skin of the chest. DBS is used to treat several disorders of movement, including dystonia. In dystonia, the electrodes are inserted into a brain region called the globus pallidus. Globus pallidus stimulation can be very effective therapy for dystonia. However not all patients are equally responsive and therapeutic outcomes can be frustratingly variable. The reason for this variability is unclear. Such variability in response may need to be met by tailoring stimulation to individual patients. Another issue with deep brain stimulation is battery life. Eventually, batteries become depleted and need to be replaced. Such battery replacements require an operation, hospital stay and the risk of introducing infection. The high electrical energy that has been used to treat dystonia means that batteries are typically replaced every year or two. The artificial electrical signals of deep brain stimulation are delivered with three parameters; frequency (Hertz - Hz), voltage (volts) and pulse width (microseconds). It has recently been reported that lower frequency stimulation, at 60Hz rather than 130Hz, can be used effectively to treat dystonia. Such 60Hz stimulation may be more effective for some patients than others. The lower energy demands of 60Hz stimulation would also greatly improve battery life (potentially doubling battery life). The aim of this study is to assess if 60Hz stimulation is more effective in ameliorating the dystonia of patients who have responded poorly to 130Hz pallidal stimulation. The current status of the evidence is one of clinical equipoise (uncertainty) and therefore suits a double blinded randomised trial.

Conditions

Dystonia

Keywords

Dystonia

Outcome Measures

Primary Outcomes (1)

• To assess if the stimulation frequency of 60 Hz is superior to 130 Hz for patients with primary dystonia who have responded poorly to standard 130 Hz pallidal stimulation

  6 months

Secondary Outcomes (1)

• Assess any potential changes in anxiety, mood, cognition

  6 months

Study Arms (2)

60 Hz stimulation

EXPERIMENTAL

Experimental reduced frequency pallidal stimulation

Procedure: Alteration of deep brain stimulator settings

130 Hz stimulation

NO INTERVENTION

Current standard pallidal stimulation setting

Procedure: Alteration of deep brain stimulator settings

Interventions

Alteration of deep brain stimulator settings PROCEDURE

From 130Hz to 60Hz pallidal stimulation

130 Hz stimulation; 60 Hz stimulation

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Primary dystonia (focal cervical or generalised dystonia) who are receiving chronic (\>1 year) bilateral pallidal stimulation but have had poor therapeutic responses (\< 50% improvement in relevant dystonia severity rating scale\*) despite confirmation of accurate electrode position.
• Able to understand study requirements - able to provide consent.
• Relevant dystonia rating scales: Cervical dystonia - severity subsection of the Toronto Western Hospital spasmodic torticollis rating scale; Generalised dystonia - severity section of the Burke Fahn Marsden rating scale.

You may not qualify if:

• None.

Sponsors & Collaborators

• University of Oxford: lead

Study Sites (1)

University of Oxford, Nuffield Department of Surgery

Oxford, Oxfordshire, OX3 9DU, United Kingdom

RECRUITING

MeSH Terms

Conditions

Dystonia

Condition Hierarchy (Ancestors)

Dyskinesias; Neurologic Manifestations; Nervous System Diseases; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Officials

• Tipu Aziz, Professor

  University of Oxford, Nuffield Department of Surgery

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Wesley Thevathasan, MBBS FRACP

CONTACT

07748729186; wesley.thevathasan@nds.ox.ac.uk

Julian Woollard, MMBS BSc

CONTACT

07779 654 944; julian.woollard@doctors.org.uk

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER

Study Record Dates

• First Submitted: September 3, 2009
• First Posted: September 4, 2009
• Study Start: September 1, 2009
• Primary Completion: January 1, 2010
• Study Completion: February 1, 2010
• Last Updated: October 14, 2009

Record last verified: 2009-09

Locations

GB (1)