Use of Interventional MRI for Implantation of Deep Brain Stimulator Electrodes

Deep brain stimulation (DBS) is a new but increasingly common surgical technique for the
treatment of Parkinson's disease and dystonia. The current technical approach to DBS
implantation involves frame-based stereotaxy. In this method, a stereotactic frame is
rigidly fixed to the patient's skull, an MRI is obtained, an anatomic target is identified,
and the coordinates of the target in stereotactic space are calculated. Instruments are
mounted on the stereotactic frame that point to the calculated coordinate. However, due to
the inherent inaccuracies in standard frame-based stereotaxy, a complex 6-hour procedure
then ensues to "map" the brain target with microelectrodes, place the lead, and return to
the MR unit to confirm proper placement.

The goal of this project is to test the feasibility of performing DBS implantation entirely
within the Phillips 1.5T and a Siemens 3T open magnet MRI machine. Prior to study
initiation, instrumentation and MR protocols were tested using a phantom head. In the
proposed project, subthalamic nucleus or globus pallidus DBS implantations will be performed
bilaterally in patients with Parkinson's disease or dystonia. Patients will be under general
anesthesia. Targeting and lead verification are performed with imaging alone, without
physiologic mapping. Data is to be gathered on the following: operative time, degree of
benefit with bilateral implantation (changes in standard rating scales of motor disability),
DBS voltage requirements, complications), and electrode location by MR. These measures will
be compared with our historical controls, previously entered into our research database, in
which electrodes were placed by the standard methods. We expect that the use of near real
time MR will improve the speed and accuracy of DBS implantation, and eliminate the need for
invasive physiological monitoring.

Parkinson's Disease

Inclusion Criteria:

1. Diagnosis of idiopathic PD with clinically significant motor fluctuations despite
maximized anti-Parkinsonian therapy. This will be based on medical history,
neurologic examination (the presence of at least 2 of the following: resting tremor,
rigidity, or bradykinesia), and response to anti-Parkinsonian therapy.

2. Approximately 5 years' duration, relative to the date of surgery, since diagnosis of
PD.

3. Age >20 inclusive, on date of surgery.

4. The subject is ambulatory in their best on time (not wheelchair bound).

5. The subject is medically able to undergo the surgery as determined by clinical and
laboratory evaluations and any other evaluations that are part of the standard
practice at the institution in which the subject is to undergo surgery (e.g.,
subjects will have normal coagulation tests and normal platelet levels).

6. The subject is expected to be able to comply with and understand the required visit
schedule and all required tests and procedures.

7. Signed IRB-approved informed consent is obtained before any study-specific procedure,
including assessments required during the eligibility evaluation period.

Exclusion Criteria:

1. In the judgment of the investigator, a history of any clinically significant medical,
psychiatric, or laboratory abnormality for which participation in the study would
pose a safety risk to the subject.

2. History of treatment of PD by any procedure involving intracranial surgery or
implantation of a device.

3. MRI of the brain within 12 months before the surgery which demonstrates an
intracranial abnormality that would contraindicate surgery (e.g. stroke, tumor,
vascular abnormality affecting the DBS target area).

4. Any disorder that precludes a surgical procedure (e.g., signs of sepsis or
inadequately treated infection) or alters wound healing.

5. Receipt of antiplatelet agents for at least 10 days prior surgery.

6. Significant cognitive impairment based on investigator assessment during the
eligibility evaluation period.

7. History of significant psychiatric illness, epilepsy, or Alzheimer's disease.

8. Active drug or alcohol abuse.

9. Pregnancy or lack of effective contraception in women of childbearing potential
defined as one year post-menopausal or surgically sterile.

10. Treatment with non anti-Parkinsonian agents (e.g., atypical neuroleptics) that may
affect symptoms of PD within 60 days before entering the study.

11. Any medical disability (e.g., severe degenerative arthritis, compromised nutritional
state, severe peripheral neuropathy) that would interfere with the assessment of
safety and efficacy in this trial.

12. Inability to follow-up with post-operative study visits

13. Inability to speak or read English

Dystonia Inclusion Criteria

1. Dystonia diagnosed by a movement disorders neurologist

2. Significant functional impairment despite optimal medical management, including
failed botulinum toxin therapy if appropriate

3. Age >20 years inclusive, on date of surgery.

4. The subject is medically able to undergo the surgery as determined by clinical and
laboratory evaluations and any other evaluations that are part of the standard
practice at the institution in which the subject is to undergo surgery (e.g.,
subjects will have normal coagulation tests and normal platelet levels).

5. The subject is able to comply with and understand the required visit schedule and all
required tests and procedures.

6. Signed IRB-approved informed consent is obtained before any study-specific procedure,
including assessments required during the eligibility evaluation period.

Exclusion Criteria

1. Any disorder that precludes a surgical procedure (e.g., signs of sepsis or
inadequately treated infection) or alters wound healing.

2. Receipt of antiplatelet agents for at least 10 days prior surgery.

3. Significant cognitive impairment based on investigator assessment during the
eligibility evaluation period.

4. History of significant psychiatric illness, epilepsy, or Alzheimer's disease.

5. Active drug or alcohol abuse.

6. Pregnancy or lack of effective contraception in women of childbearing potential
defined as one year post-menopausal or surgically sterile.

7. Any medical disability (e.g., severe degenerative arthritis, compromised nutritional
state, severe peripheral neuropathy) that would interfere with the assessment of
safety and efficacy in this trial.

8. Inability to follow-up with post-operative study visits

9. Inability to speak or read English