1. Combination of Frameless Navigation and Intraoperative Neurophysiology for Motor Cortex Stimulation Konstantin Slavin, MD, and Keith R. Thulborn, MD, PhD Section of Stereotactic and Functional Neurosurgery, Department of Neurosurgery, and Center for MRI Research University of Illinois at Chicago

2. Central Deafferentation Pain Etiology - Post-stroke - Iatrogenic Other terms -“Thalamic pain” -“Anesthesia dolorosa” Treatment options -Strong opioids / antidepressants -Intrathecal medications -Further destruction (i.e., cingulotomy, tractotomy) -Neurostimulation

3. Non-destructive option Motor cortex stimulationMotor cortex stimulation 15 year history15 year history Long-term effect?Long-term effect? Mogilner, 2001 Central Deafferentation Pain Mechanism: -Cortico-thalamic inhibition -Cortico-cortical inhibition -Non-opioid dependent -Placebo effect? -Motor function required Mechanism: -Cortico-thalamic inhibition -Cortico-cortical inhibition -Non-opioid dependent -Placebo effect? -Motor function required

4. Technique variations: -Anatomical vs. physiological targeting -CT vs. MRI -Craniotomy vs. burr hole -Subdural vs. epidural placement -Grid placement vs. intraoperative recording -Awake vs. under GA -One or more electrodes Technique variations: -Anatomical vs. physiological targeting -CT vs. MRI -Craniotomy vs. burr hole -Subdural vs. epidural placement -Grid placement vs. intraoperative recording -Awake vs. under GA -One or more electrodes Motor Cortex Stimulation

5. UIC MCS protocol 1.Preoperative phase 2.Surgery 1 3.Stimulation trial 4.Surgery 2 5.Postoperative phase 1.Preoperative phase 2.Surgery 1 3.Stimulation trial 4.Surgery 2 5.Postoperative phase 1.Clinic assessment 2.Baseline MRI / fMRI 3.Neuropsychological testing 4.Repeated Q/A sessions 5.Medical clearance 1.Clinic assessment 2.Baseline MRI / fMRI 3.Neuropsychological testing 4.Repeated Q/A sessions 5.Medical clearance

6. 1.Skin fiducials UIC MCS protocol 1.Preoperative phase 2.Surgery 1 3.Stimulation trial 4.Surgery 2 5.Postoperative phase 1.Preoperative phase 2.Surgery 1 3.Stimulation trial 4.Surgery 2 5.Postoperative phase

7. 2. Stereotactic fMRI UIC MCS protocol 1.Preoperative phase 2.Surgery 1 3.Stimulation trial 4.Surgery 2 5.Postoperative phase 1.Preoperative phase 2.Surgery 1 3.Stimulation trial 4.Surgery 2 5.Postoperative phase

8. 3. Frameless navigation UIC MCS protocol 1.Preoperative phase 2.Surgery 1 3.Stimulation trial 4.Surgery 2 5.Postoperative phase 1.Preoperative phase 2.Surgery 1 3.Stimulation trial 4.Surgery 2 5.Postoperative phase

9. 4. Open craniotomy UIC MCS protocol 1.Preoperative phase 2.Surgery 1 3.Stimulation trial 4.Surgery 2 5.Postoperative phase 1.Preoperative phase 2.Surgery 1 3.Stimulation trial 4.Surgery 2 5.Postoperative phase

10. 5. Intraoperative SSEP (look for N20 peak reversal) 5. Intraoperative SSEP (look for N20 peak reversal) UIC MCS protocol 1.Preoperative phase 2.Surgery 1 3.Stimulation trial 4.Surgery 2 5.Postoperative phase 1.Preoperative phase 2.Surgery 1 3.Stimulation trial 4.Surgery 2 5.Postoperative phase

11. 6. Electrode insertion (Resume, Medtronic) UIC MCS protocol 1.Preoperative phase 2.Surgery 1 3.Stimulation trial 4.Surgery 2 5.Postoperative phase 1.Preoperative phase 2.Surgery 1 3.Stimulation trial 4.Surgery 2 5.Postoperative phase

12. -Daily stimulation -ICU stay -Daily stimulation -ICU stay UIC MCS protocol 1.Preoperative phase 2.Surgery 1 3.Stimulation trial 4.Surgery 2 5.Postoperative phase 1.Preoperative phase 2.Surgery 1 3.Stimulation trial 4.Surgery 2 5.Postoperative phase

13. UIC MCS protocol 1.Preoperative phase 2.Surgery 1 3.Stimulation trial 4.Surgery 2 5.Postoperative phase 1.Preoperative phase 2.Surgery 1 3.Stimulation trial 4.Surgery 2 5.Postoperative phase 1.Electrode internalization 2.GA 1.Electrode internalization 2.GA

14. UIC MCS protocol 1.Preoperative phase 2.Surgery 1 3.Stimulation trial 4.Surgery 2 5.Postoperative phase 1.Preoperative phase 2.Surgery 1 3.Stimulation trial 4.Surgery 2 5.Postoperative phase 1.Programming 2.1 wk of antibiotics 3.Re-programming 4.Re-programming 5.… 1.Programming 2.1 wk of antibiotics 3.Re-programming 4.Re-programming 5.…

15. Motor Cortex Stimulation Pros: -Non-destructive -Testable -Reversible -Adjustable -50% success -The only option? Pros: -Non-destructive -Testable -Reversible -Adjustable -50% success -The only option? Cons: -Price -Time consuming -Hardware complications -50% success -FDA status -Mechanism? Cons: -Price -Time consuming -Hardware complications -50% success -FDA status -Mechanism?

16. MCS - Conclusions -Using a combination of functional MRI, image-guided computer navigation, and intraoperative electrophysiological testing, we were able to precisely localize the primary motor cortex and subsequently achieve excellent pain relief in patients with medically intractable deafferentation pain. -The motor cortex stimulation may be an option for patients with chronic pain syndromes due to strokes, post-surgical procedures and other deafferentative conditions. -Using a combination of functional MRI, image-guided computer navigation, and intraoperative electrophysiological testing, we were able to precisely localize the primary motor cortex and subsequently achieve excellent pain relief in patients with medically intractable deafferentation pain. -The motor cortex stimulation may be an option for patients with chronic pain syndromes due to strokes, post-surgical procedures and other deafferentative conditions.