1. Bologna 2010 Use of Cervical Spinal Cord Stimulation to Treat and Prevent Arterial Vasospasm after Aneurysmal Subarachnoid Hemorrhage Konstantin Slavin, MD Prasad Vannemreddy, MBBS, MS Eduardo Goellner, MD Ali Alaraj, MD; Nada Mlinarevich, RN, MPH; Karriem Watson, MD; Leena E. Walters, BS; Sepideh Amin-Hanjani, MD; Victor Aletich, MD; Fady T. Charbel, MD Konstantin Slavin, MD Prasad Vannemreddy, MBBS, MS Eduardo Goellner, MD Ali Alaraj, MD; Nada Mlinarevich, RN, MPH; Karriem Watson, MD; Leena E. Walters, BS; Sepideh Amin-Hanjani, MD; Victor Aletich, MD; Fady T. Charbel, MD Department of Neurosurgery University of Illinois at Chicago Department of Neurosurgery University of Illinois at Chicago

2. Bologna 2010 Background CBF changes with SCS (Hosobuchi, 1985) 10 patient study (Takanashi, 2000)

3. Bologna 2010 First hypothesis Based on past laboratory and anecdotal clinical experience, we hypothesized that prolonged cervical spinal cord stimulation (cSCS) in acute settings of aneurysmal subarachnoid hemorrhage (aSAH) would be both safe and feasible, and that 2-week stimulation will reduce incidence of cerebral arterial vasospasm.

4. Bologna 2010 Cervical SCS for Vasospasm IDE study No commercial sponsor / investigator initiated Safety / feasibility Acute study, long-term follow up Single arm – no placebo / control group No blinding / randomization 12 patients Single cervical SCS electrode - externalized 14 days of stimulation Daily spasm monitoring (TCD, CT, CTA, angio) 3, 6 and 12 months follow up

5. Bologna 2010 Procedure Cervical SCS for Vasospasm Single 8-contact electrode Insertion at C7-T1 or T1-2 Midline placement up to C2 Posterior epidural space Immediately upon completion of aneurysm-securing procedure General anesthesia Lateral position Subcutaneous tunneling

6. Bologna 2010 Patient Data Age: 27-62 (mean – 49) 4 men, 8 women H&H – 2.9, Fisher – 3.3 3 coiled, 9 clipped 5 AComm, 3 PComm, 2 MCA, 1 ICA, 1 pericallosal Recruitment pattern

7. Bologna 2010 Results 1 death (multi-system failure) 2 electrode pullouts (days #7 and 13) 0 insertion complications 0 infections 0 CSF leaks

8. Bologna 2010 Results No issues with feasibility “Treatment as usual” Daily TCD; CT and angio as needed Stimulation parameters: Frequency – 60 Hz Pulse width – 200 mcsec Amplitude – 2.25 mA (1.6-3.0)

9. Bologna 2010 Results Clinical vasospasm 2 patients (17%) Angiographic vasospasm 9 events in 6 patients (50%)

10. Bologna 2010 Results Predicted rate of vasospasm – 50-80% angiographic, 33-40% clinical (based on H&H and Fisher grades) Actual rate of vasospasm – 50% angiographic, 17% clinical Long-term outcome: 1 death (during acute treatment) no disability, no stroke, no vasospasm-related adverse events

11. Bologna 2010 Conclusions Cervical SCS electrodes may be safely implanted in patients with aneurysmal SAH It is feasible to perform 2 week continuous SCS in high-intensity ICU settings The vasospasm rate is lower than predicted No vasospasm-related mortality / morbidity in entire cohort (12 months follow up completed in all patients)

12. Bologna 2010 Second hypothesis

13. Bologna 2010 Findings Correlation between the position of active contacts within SCS electrode and vasospasm occurrence. Clinical vasospasm occurred only in those patients who were stimulated at mid-cervical level (C4-5) (n=2) and not in those where active contacts were above C4 (n=10).

14. Bologna 2010 Conclusions Cervical SCS electrodes may be safely implanted in patients with aneurysmal SAH It is feasible to perform 2 week continuous SCS in high-intensity ICU settings The vasospasm rate is lower than predicted No vasospasm-related mortality / morbidity in entire cohort (12 months follow up completed in all patients) Location of active cSCS contacts may contribute to prophylactic cSCS effects in post-aSAH vasospasm patients.