Cerebral Metabolic Changes Associated With Thalamic Stimulation

The Hospital for Sick Children

Status and phase: Terminated; Phase 3

Conditions: Epilepsy

Treatments: Procedure: Magnetic Resonance Imaging (MRI); Other: Neuropsychological Testing; Procedure: Positron Emission Tomography (PET) Scan

Study type: Interventional

Funder types: Other

Identifiers

NCT01141764

1000014496

Details and patient eligibility

About

The purpose of this research study is to evaluate the brain circuits function and circuits involved in the mechanism of thalamic DBS in patients with medically refractory epilepsy.

Full description

Deep brain stimulation (DBS) of the anterior nucleus of the thalamus in patients with medically refractory epilepsy has been shown to be efficacious. Studies have estimated a 46-76% reduction in seizures relative to the baseline. However, the exact anatomic circuitry involved in the mechanism of DBS in epilepsy remains unknown. Positron emission tomography (PET) studies can provide clues to the metabolic activity associated with DBS activation. In our study, patients will be scanned with their DBS electrodes turned "on" and "off". PET data captured during these two distinct states may show characteristic differences in cerebral glucose metabolism and modulatory effects of surrounding cerebral structures, thus providing clues to how DBS works to prevent seizures.

Enrollment: 4 patients

Sex: All

Ages: 18 to 85 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• 18-85 years old
• currently have DBS implanted for medically refractory epilepsy
• Women of childbearing age will be required to use established contraceptive methods while enrolled in the study.

Exclusion criteria

Patients who:

• are < 18 years of age or > 85 years of age
• are medically unstable
• are women who are potentially pregnant, pregnant or nursing
• have had PET imaging within 1 year.

Trial design

Primary purpose: Treatment

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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4 participants in 1 patient group

Study Group

Experimental group

Description:

In our study, patients will be scanned with their DBS electrodes turned "on" and "off". Participation involves undergoing 2 separate PET scans on 2 separate days. The MRI and neuropsychological tests will either be performed on the same day as one of the PET scans or on a separate day. Procedures performed in this study are not part of the standard management of epilepsy.

Treatment:

Other: Neuropsychological Testing

Procedure: Magnetic Resonance Imaging (MRI)

Procedure: Positron Emission Tomography (PET) Scan