1. DBS for Dystonia: Stereotactic Technique
Joshua M. Rosenow, MD, FAANS, FACS
Director, Functional Neurosurgery
Associate Professor of Neurosurgery, Neurology and
Physical Medicine and Rehabilitation
Northwestern Memorial Hospital

2. Disclosures
I have no relationship, financial or otherwise, relevant to this presentation
I do surgery for dystonia and feel that it is very effective for the appropriate patients
I am very nervous about the Yankees 2013 season (Although Arod’s hip surgery will increase their OPS through June)

3. Dystonia Surgery
1641 – Minnius sections the sternocleidomastoid muscle in a patient with cervical dystonia
1891 – Keen performs first selective rhizotomy for cervical dystonia
1924 – McKenzie performs sectioning of both anterior and posterior spinal roots as well as spinal accessory nerve
1930 – Dandy performs first selective sectioning of spinal roots for cervical dystonia
Servant, maid

4. Dystonia Surgery
1940 – Myers – destructive procedures in the basal ganglia alleviate tremor
1950 – Spiegel and Wycis – adapt their stereotactic frame for pallidothalamotomies for chorea
1960s – Thalamotomies and Pallidotomies for dystonia
Servant, maid

5. Dystonia Surgery
1960s - Cooper begins performing cerebellar stimulation for dystonia and other movement disorders and epilepsy
1991 – Intrathecal baclofen infusion
1999 – Kumar – pallidal stimulation in single patient for primary dystonia
Krauss - pallidal stimulation for cervical dystonia
Servant, maid

6. DBS History
Harry Benson suffers from painful, violence-inducing seizures. In an effort to alleviate this problem, Benson undergoes an experimental medical procedure, Stage 3, in which electrodes are attached to his brain's trouble spots -- if all goes well, timed jolts of electricity will correct his disability. But when Benson learns to turn up the juice whenever he pleases, his murderous rampage begins.
Servant, maid

7. DBS for Dystonia: FDA Approval
2003 – HDE – Humanitarian Device Exemption granted
Approved for primary dystonia only
GPi or STN DBS
Requires IRB approval but is not research

8. Dystonia DBS: Candidates
Severe, disabling symptoms from primary dystonia
Should have failed several modalities of treatment
Inadequate response or unacceptable side effects
Good support system
No medical contraindications
No significant untreated depression or anxiety
No significant cognitive deficits

9. Gpi Targeting Anatomic GPI target Trajectory
T1 inversion recovery (IR) sequences very useful do delineate GPI borders
Anatomic GPI target
Relative to intercommissural line
18-22 mm lateral
2-3 mm anterior
4 mm inferior
Trajectory
AP Angle ~600
Coronal angle 0-50

10. Gpi Targeting Anterior commissure
Another method of choosing/verifying anatomic target is to start over lateral border of optic tract and set target just above that
Anterior commissure
Putamen
Pallidum

11. Gpi MER Start at anatomic target Want to record at least 6-7mm Gpi
Good kinesthetic activity
Determine posterior border
Move posteriorly in 3 mm increments per MER track until internal capsule is reached (as determined by microstimulation-evoked contractions)
Determine ventral border
Obtain evoked potentials from optic tract
Final positioning of DBS electrode tip:
at least 2 mm dorsal to OT
at least 4 mm anterior to capsular border

12. Gpi MER Compared to Gpi in PD, Gpi in dystonia:
has lower neuronal firing rate
is characterized by less distinction between GPe and Gpi in terms of MER characteristics, making the transition determination more challenging

13. GPi

14. Frame Placement

16. Striatum
Sparse Cells
Firing Rates: 0.1Hz to 50Hz
Low Amplitude

17. GPe Denser Cellularity Spontaneous Background Activity
Two Distinct Cellular Patterns
Pauser Cells
Burster Cells

18. Pauser Cells Irregular firing pattern Frequency: 30-200 Hz
Moderate to high amplitude

19. Burster Cell Cluster rate slow (10-20 Hz)
Burst Frequency high (> 500 Hz)
Medium to high amplitude

20. Border Cells Firing rates 10-40 Hz Large amplitudes
No movement initiated responses

21. GPi Dense Cellularity Spontaneous Background Activity
Two Distinct Cellular Patterns
Tremor Cells
High Frequency Cells
Kinesthetic Responses

22. High Frequency Cells Frequency: 50-300 Hz Kinesthetic responses
Large Amplitudes

23. Pallidal MER
Optic
GPi
Laminae
GPe
Putamen

25. Physiologic Verification
Intraoperative test stimulation
Clinical benefits - NONE
Side effects
Muscle contractions too close to IC
Flashing lights – too close to OT
Slurred speech – too close to IC

26. Programming Begin 4 weeks after surgery
Effects may not be seen for days

27. DBS for Dystonia Surgical selection needs refinement
Primary dystonia does best
Multiple targets have been tried over the years
GPi, STN, Voa, Vop
Intraoperative physiology differs from PD
Programming more complex
Higher current than PD
Delays to improvement
While prospective studies are emerging, more are needed to refine the procedure

28. DBS: Risks Not everyone experiences the same amount of improvement
Inability to guarantee a certain level of improvement
Stimulation-related side effects
Infection – 5% per side
Hardware breakage
Rare in general but higher in dystonia patients due to abnormal movements (esp. cervical dystonia)
Bleeding – 1-3%
Anesthesia risks
Activa Tremor Control Therapy has been available in Europe, Canada and Australia since 1995 and in the US since 1997
Medicare will provide coverage for this therapy in all 50 US states.
Check with your private insurer to determine your benefits.
Private insurance will require prior authorization. Your physician’s office can assist you with determining whether your plan will cover Activa Therapy.
Out of pocket expense will vary based on benefit plan.
Go to with specific questions.
Speaker may also opt to give out the contact information for Medtronic’s Therapy Access Group:

29. Thank you for coming!