Evoked Potential Recording During DBS Surgery

Intraoperative Evoked Potential Recording for Localization of Deep-Brain Stimulation Electrodes

Deep brain stimulation (DBS) has been approved for treatment of dystonia by the FDA under a humanitarian device exemption (HDE) status. DBS has been shown to be very effective in the treatment of a variety of diseases such as Parkinson's disease and essential tremor. It has been widely used for the treatment of primary and secondary dystonia as well. Surgery involves the placement of the DBS electrode in one or two of the deep nuclei constituting the basal ganglia. A subcutaneous thoracic or abdominal implantable pulse generator is placed and connected to the intracranial electrode. Pulsatile stimulation of the deep brain nuclei has been shown to result in significant improvement in many patients, including restoration of the ability to walk or make voluntary arm movements. A major difficulty with DBS is the accurate placement of the electrode. Adult patients are usually awakened during surgery and micro electrode recordings are used to determine the optimal electrode effectiveness and monitor for side effects. This requires the patient to be awake and cooperate, while on the operating table. When DBS is performed in children, such testing is often not possible because the children are scared or not cooperative when awakened during surgery, the procedure is most often done for Dystonia, which does not respond immediately, and dystonia may cause involuntary movements that could be dangerous in the operating room while the child's brain is exposed. As part of the routine clinical evaluation of target location in the operating room or Neuromodulation Unit, stimulation is performed using the deep brain or depth electrodes, typically at frequencies between 60hz and 185hz. For this research study, stimulation will occur at much lower frequencies, between 9hz and 20hz in order to be able to measure how electrical activity from the deep electrodes spreads to other electrodes or the scalp. As part of the research, peripheral nerves will also be stimulated at the wrist and knee at frequencies of 20hz to 150hz in order to measure the transmission of peripheral nerve stimulation to these areas of the brain. The investigators hope these additional studies will allow discovery for mechanisms that lead to movement disorders including dystonia, and that knowledge of these mechanisms will allow the investigators to develop new, safer, and more effective treatments in the future.

Study Overview

• Status: Completed
• Conditions: Movement Disorders in Children
• Intervention / Treatment: Other: Deep Brain Stimulation

• Study Type: Observational
• Enrollment (Actual): 26

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 5 years and older (Child, Adult, Older Adult)
• Accepts Healthy Volunteers: N/A
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Has plans to be implanted with a deep brain stimulator device. Although Medtronic's product information indicate that DBS is for individuals 7 years of age and older some DBS centers such as UCSF have implanted kids younger for off-label use. By including children 5 years of age into our study, we do not exclude children that may receive DBS off-label.

Description

Inclusion Criteria:

• - Subjects 5 years of age and/or older (including adults, ages 18+)
• Has chronic, intractable (drug refractory), generalized dystonia
• DBS surgery must be clinically indicated

Exclusion Criteria:

• Contraindication to neurosurgery and or a potentially reversible cause of dystonia that does not include surgery.

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Assessment of Change in Dystonia using the Barry Albright Dystonia Scale	The Barry-Albright Dystonia Scale (BADS) is the most common outcome measure reported in intervention studies for children with dyskinetic cerebral palsy. Dystonia severity is rated on a 5-point (0 - 4), criterion based, ordinal scale for eight body regions (eyes, mouth, neck, trunk, left/right upper extremities and left/right lower extremities. The minimum score value is 0 (least severe) and the maximum score value is 32 (most severe).	1,3,6,12 months

Collaborators and Investigators

• Sponsor: University of Southern California

Publications and helpful links

General Publications

• Hernandez-Martin E, Arguelles E, Zheng Y, Deshpande R, Sanger TD. High-fidelity transmission of high-frequency burst stimuli from peripheral nerve to thalamic nuclei in children with dystonia. Sci Rep. 2021 Apr 19;11(1):8498. doi: 10.1038/s41598-021-88114-w.

Study record dates

Study Major Dates

• Study Start (Actual): November 13, 2013
• Primary Completion (Actual): October 1, 2019
• Study Completion (Actual): November 2, 2021

Study Registration Dates

• First Submitted: May 18, 2022
• First Submitted That Met QC Criteria: May 24, 2022
• First Posted (Actual): May 26, 2022

Study Record Updates

• Last Update Posted (Actual): May 26, 2022
• Last Update Submitted That Met QC Criteria: May 24, 2022
• Last Verified: May 1, 2022

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Central Nervous System Diseases; Nervous System Diseases; Movement Disorders
• Other Study ID Numbers: CCI-13-00324

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No