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New Paradigms in Spinal Cord Stimulation Steven Falowski MD Objectives Background of SCS Mechanisms of Action Indications Equipment Placement Introduction Spinal cord stimulation (SCS) delivers electrical current to the spinal cord Ideal for Neuropathic Pain Adjustable Non- Destructive Neuromodulatory Indications Most Common Post-laminectomy syndrome Complex regional pain syndrome (CRPS) Ischemic limb pain Angina Other visceral/abdominal pain cervical neuritis pain spinal cord injury pain post-herpetic neuralgia neurogenic thoracic outlet syndrome Background Initially all unipolar electrodes Set Programming Only radio-frequency (RF) driven passive receivers were available. Background 1970’s: Pulse Generator 1980’s: Percutaneous electrode Waltz et al 1982: First percutaneous quadripolar electrode 2004: Rechargeable Battery Mechanism of Action 1980-1990 Holsheimer, Coburn, and Strujik: Distribution of the electrical fields within the spinal structures 1997- Holsheimer et al: Effect of anodecathode configuration on paresthesia coverage in spinal cord stimulation Mechanism Of Action Barolat 1993: Mapping of sensory responses Barolat 1998: Anatomical and electrical properties of the intraspinal structures and clinical correlations Mechanism of Action Foreman et al. 1976 Primate Studies Linderoth et al. 1992 Rat Studies At the chemical level, animal studies suggest that the SCS triggers the release of serotonin, substance P, and GABA within the dorsal horn ?Descending Inhibition Mechanism of Action-Electrodes Indications Post Laminectomy Syndrome CRPS Angina Abdominal/Visceral Pain 50% pain relief in 5060% of the patients Maintained over several years Post- Laminectomy Syndrome Etiology: Pain in Center Lower Lumbar Area Pain in Buttocks Radicular Pain Also included: Arachnoiditis Epidural Fibrosis Radiculitis Microinstability Recurrents Disc Herniations Infections Stimulation of the Low Back Single vs Dual Electrode Law et al: Multiple Bipole Arrays North et al: Midline Quadripolar Electrode Tripole Electrode Steer Current Sharan 2007: Lateral anodes increase discomfort threshold Post- Laminectomy Syndrome Marchand et al: Pain scores reduced with SCS Prospective RCT Acted as Own Control Small Study Group Post- Laminectomy Syndrome North et al-1991: SCS is superior to repeat surgery 50 patients Average 3 surgeries for FBSS prior to SCS 53% of patients had pain relief at 2.2 years Patient Satisfaction North et al-1995: Better outcomes with SCS Prospective RCT Repeat back surgery vs SCS Allowed Crossover Post- Laminectomy Syndrome Turner-1995: Systematic Review of Literature 41 articles from 1966-1994 50-60% of patients had greater than 50% pain relief Burchiel et al-1996: 55% Successful Stimulation Prospective Multi- Center one year trial Post- Laminectomy Syndrome Cameron 2004-JNS: 51 studies Total of 3,700 patients SCS had a positive, symptomatic, long-term effect in cases of: refractory angina pain, severe ischemic limb pain secondary to peripheral vascular disease, peripheral neuropathic pain, and chronic low-back pain Complex Regional Pain Syndrome Pain and swelling in a single body part Pain may start after an injury Pain will usually gradually worsen Usually affects the hands, feet, elbows or knees Two Types: Type I: May not have cause Type II: Always follows an injury Complex Regional Pain Syndrome Complex Regional Pain Syndrome Challenges: Pain is not well defined Difficult to cover affected area with stimulation May aggravate original pain CRPS-Early Work Barolat et at-1989 Pain reduction in 10 of 13 patients Short follow up Kumar et al- 1997 41 month follow up of 12 patients All patients with pain relief CRPS-More Recent Data Kemlar -1999: 78% pain relief 23 patients Kemlar- 2000: SCS vs Physical Therapy 54 Patients randomized 67% pain relief at 6 months Improved VAS scores Kemlar- 2006: Diminished effectiveness over 5 year follow up CRPS-Limitations Difficult to cover affected area with stimulation Long- term efficacy is yet to be determined Improvement in pain scores, but not necessarily improvement in functional impairment Angina Factors Involved EKG changes Time to Angina Exercise Capacity Recovery Time Use of Nitrates Anginal Attacks End Results Ischemia Myocardial Flow MI Arrhythmias Angina-Use of SCS Lower cervical and upper thoracic region Continuous vs cyclical use Often use a low intensity stimulation for several hours per day for prophylactic purposes Eddicks S et al(2007): Continuous sub threshold stimulation RCT demonstrating improved functional status and symptoms “Blinded” Angina-Efficacy of SCS DeJongste et al 1994: decrease in anginal attacks and nitrate consumption Treatment group as Control DiPede 2003: Immediate and long- term clinical outcome with SCS Prospective 104 pts with SCS for refractory angina Decrease anginal episodes at rest and with activity Angina-Efficacy of SCS Vulink et al -1998: Improved pain and quality of life Hauvast et al-1998: Increased exercise duration and time to Angina Decreased Anginal Attacks Decreased use of Nitrates Decreased Ischemic episodes on EKG Angina-ESBY Study Mannheimer et al 1998-2002: RCT: CABG vs SCS Prospective Non- Blinded Trial SCS/CABG: Both with 30% Improvement NHP scores 5 year Mortality: 27% in both groups No difference in the percentage of cardiac deaths Angina-ESBY Study Mannheimer et al 1998-2002: Cardiac Events were similar across the groups *More Cerebrovascular events observed in CABG group* Eight in CABG group/Two in SCS group Both groups had decrease in anginal attacks and decreased nitrate use No significant inter-group difference Angina- ESBY Study Study Limitations: Limited number of patients Limited follow-up time Not Blinded Conclusion of ESBY Study CABG and SCS appear to be equivalent methods in terms of symptom relief SCS may be a therapeutic alternative for patients with an increased risk of surgical complications Angina-Mechanism of SCS Homogenization of myocardial blood perfusion with SCS Augustinsson et al-1995: SCS patients have improved heart muscle lactate metabolism, oxygen demand, and blood flow in the coronary sinus Hautvast et al: No change in HR variability after 6 weeks i.e. autonomic modulation may not be the explanatory mechanism of action Angina-Mechanism of SCS Foreman/Linderoth: Pain Relief from direct inhibition of signal or decrease in ischemia? Decreased activity in Spinothalamic/Sympathetic Tracts in Rat Model Hautvast et al-1996: Positron emission tomography study Redistribution of myocardial flow in favor of ischemic parts of the myocardium Both at rest and after pharmacologic stress induction Demonstrated as a long- term effect of SCS Angina The role of SCS in the management of refractory angina pectoris seems to be very promising Uniformly good results in the relief of Anginal pain shown in the literature Results maintained in long- term follow up Effects go beyond pain relief Abdominal/Visceral Pain 20% of the population in United States has abdominal pain Many etiologies gastrointestinal genitourinary musculoskeletal nervous system Treatment modalities Cognitive- behavioral Physical Pharmacological therapies More Invasive: Celiac plexus blocks Celiac ganglia destruction Abdominal/Visceral Pain-Initial Interest Some studies have demonstrated some localization in the spinal cord for visceral pain secondary to malignancy Hirschberg-1996: Increased Dorsal Column Activity Midline Myelotomy Abdominal/Visceral Pain-Initial Interest Case Reports: Ceballos et al-2000: Mesenteric Ischemia Reduction in pain scores Decrease Narcotic Use Krames et al-2004: Irritable Bowel Syndrome Reduction in diarrhea Initial reduction in pain Abdominal/Visceral Pain Khan et al-2005: Refractory Abdominal Pain Non- alcoholic pancreatitis, abdominal wall neuromas, post splenectomy pain All patients(9) had a significant improvement in VAS scores Decreased narcotic use Placement of the leads at the T5-7 level 8 month follow up Abdominal/Visceral Pain Tiede et al: Multiple abdominal surgeries 2 patients Placed at T2 Relieved postprandial pain Decrease Narcotic Use Patients returned to work Kapural et al: Chronic visceral pelvic pain 6 females Endometriosis/Multiple Surgical Explorations >50% Pain relief Decrease opiate use Decrease VAS score 30 month follow up Abdominal/Visceral PainMechanism Viscerotomes Sympathetic and Parasympathetic Pathways The sympathetic afferents in the lower thoracic/upper lumbar spinal segments have been shown to transmit painful impulses from the viscera Equipment Equipment Rapidly Changing Multiple Stimulation Parameters Multiple Types of Electrodes and Combinations Increased Uses Pulse Generators Two basic types Internal Pulse Generator Radiofrequency coupled pulse generator Rechargeable Pulse Generator Power Requirement Issues Pulse Generators IPG: Lithium Battery Activation/Control occur through an external transcutaneous telemetry device Control by patient and physician Battery life: 2.5 to 4.5 years Outpatient surgery to replace Pulse Generators Rechargeable Systems SCS Model • Large fibers activated near the cathode Transverse tripolar stimulation (4 pts) Central cathode and two lateral anodes Anodes increase the discomfort threshold over the roots compared to the paresthesia threshold (thus increasing the therapeutic range) Lateral/medial steering advantage by setting different voltages of the flanking anodes Closer spacing = More effective fiber activation - Electrode Configurations UB GC LTS-2A 2 anodes LTS-4A 4 anodes LTS-6A 6 anodes + Tripole Paddle-Summary Similar activation ratios were obtained as with trialed percutaneous leads Lower paresthesia thresholds and energy per pulse were seen with the paddle than with the percutaneous array. Trialing with one or more percutaneous arrays can aid in determining the effectiveness of paddle arrays. Awake versus non-Awake Surgery for Placement of Spinal Cord Stimulators Study Design A retrospective review of 291 internalization operations to determine whether first time awake surgery for placement of spinal cord stimulators is preferable to non-awake placement Electrode implantation can be performed either under monitored (local anesthetic and intravenous sedation) or under general anesthesia REPOSITION NEW STIMULATOR INFECTION FAILURE BATTERY EOL Surgeries Performed 61% New Implantation 16% Failure 10% Repositioning of the battery or stimulator 7% EOL of the battery 6% are due to infection Placement of Stimulator 35 30 # cases 25 20 15 10 5 0 -5 2002 2003 2004 2005 Y ear Y # No Wakeup # Wakeup 2006 Monitoring Failure Rate Non Awake Surgical Failure Rate 16% Awake Surgical Failure Rate 31% 90 80 70 #cases 60 50 No Failure Failure 40 30 * 20 10 0 Wakeup * = p<.05 No Wakeup Repositioning 90 80 70 #cases 60 50 No Reposition Reposition 40 30 20 10 0 Wakeup No Wakeup Non Awake Surgical Repositioning Rate 16% Awake Surgical Repositioning Rate 17% Infection 90 80 70 60 #cases Non Awake Surgical Infection Rate 7% Awake Surgical Infection Rate 7% 50 No Infection Infection 40 30 20 10 0 Wakeup No Wakeup Summary Important Points: Radiographical position and motor stimulation responses to assure proper electrode positioning under general anesthesia Performed after a percutaneous trial Conclusion: Non-awake surgery is associated with fewer failure rates and therefore fewer reoperations, making it a viable alternative SCS-Conclusions SCS Technology is improving Equipment and stimulation parameters Reliable and safe modality Goal of neurostimulation is to reduce pain rather than to eliminate pain 50% improvement in pain relief Reduce use of pain medications Increasing amount of uses Importance of selection criteria Thank You References 1. Waltz J.M., Andreesen W.H. : Computerized percutaneous multi-level spinal cord stimulation in motor disorders. Appl. Neurophys. 45 (1982) 73-92. 2. Coburn B. Electrical stimulation of the spinal cord: two-dimensional finite element analysis with particular reference to epidural electrodes. Medical & Biological Engineering & Computing. 1980; 18:573-84. 3. Coburn B. A theoretical study of epidural electrical stimulation of the spinal cord--Part II: Effects on long myelinated fibers. IEEE Transactions on Biomedical Engineering. 1985; 32:978-86. 4. Coburn B, Sin WK. A theoretical study of epidural electrical stimulation of the spinal cord--Part I: Finite element analysis of stimulus fields. IEEE Transactions on Biomedical Engineering. 1985; 32:971-7. 5. Holsheimer J, Struijk JJ. How do geometric factors influence epidural spinal cord stimulation? A quantitative analysis by computer modeling. Stereotactic & Functional Neurosurgery. 1991; 56:234-49. 6. Holsheimer J, Barolat G, Struijk JJ, He J. Significance of the spinal cord position in spinal cord stimulation. Acta Neurochirurgica - Supplementum. 1995; 64:119-24. 7. Holsheimer J, Wesselink WA. Effect of anode-cathode configuration on paresthesia coverage in spinal cord stimulation. Neurosurgery. 1997; 41:654-9; discussion 659-60. 8. Barolat G. : Epidural spinal cord stimulation. Anatomical and electrical properties of the intraspinal structures and clinical correlations. Neuromodulation 2 (1998) 63-71. References 9. Linderoth B, Stiller CO, Gunasekera L, O'Connor WT, Ungerstedt U, Brodin E. Gammaaminobutyric acid is released in the dorsal horn by electrical spinal cord stimulation: an in vivo microdialysis study in the rat. Neurosurgery. 1994; 34:484-8; discussion 488-9. 10. Linderoth B. Dorsal column stimulation and pain: experimental studies of putative neurochemical and neurophysiological mechanisms. In: Kongl Carolinska Medico Chirurgiska Institutet, Stockholm, 1992, 1992. 11. Foreman RD, Beall JE, Coulter JD, Willis WD. Effects of dorsal column stimulation on primate spinothalamic tract neurons. Journal of Neurophysiology. 1976; 39:534-46. 12. Barolat G, Fulvio M, He J, Seme S, Ketcik B. Mapping of sensory resposens to epidural stimulation of the intraspinal neural structures in man. J Neurosug 78: 233-239, 1993. 13. Law J.D. : Spinal stimulation in the "failed back surgery syndrome": Comparison of technical criteria for palliating pain in the leg vs. in the low back. Acta Neurochir. 117 (1992) 95. 14. North R., Kidd D.H., Olin J., Sieracki J.M., and Cutchis P.N. : Spinal cord stimulation for axial low back pain: single versus dual percutaneous electrodes. Abstracts of the 4th International Congress of the INS (1998) 212 15. Sharan, A., Miyazawa, G., Greenberg, J. and King, G. (2007, April 17): Selective Dorsal Column Activation With Three Column Electrode Arrays Using Percutaneous and Paddle Leads, Paper presented at the 2007 annual meeting in Washington DC. Abstract retrieved on the 2nd of July, 2007, from AANS library website (article ID: 40855). 16. Marchand S, Bushnell MC, Molina- Negro P: The effects of dorsal column stimulation on measures of clinical and experimental pain in man. Pain 1991; 249-257. References 17. North R.B., Ewend M.G., Lawton M.T., Kidd D.H., and Piantadosi S. : Failed back surgery syndrome: Five-year follow-up after spinal cord stimulator implantation. Neurosurg. 28 (1991) 692-699. 18. North RB, Kidd D, Piantadosi S: Spinal cord stimulation versus reoperation for failed back surgery syndrome: a proscpective, randomized study design. Acta Neurochir Suppl (Wien) 1995; 64: 106-108. 19. Turner J.A., Loeser J.D., and Bell K.G.. : Spinal cord stimulation for chronic low back pain: a systematic literature synthesis. Neurosurg 37(6) (1995) 1088-1096. 20. Burchiel K.J., Anderson V.C., Brown F.D., Fessler R.G., Friedman W.A., Pelofsky S., Weiner R.L., et al. : Prospective, multicenter study of spinal cord stimulation for relief of chronic back and extremity pain. Spine 21(23) (1996) 2786-2794. 21. Barolat G., Schwartzman R., and Woo R. : Epidural spinal cord stimulation in the management of reflex sympathetic dystrophy. Stereo. Funct. Neurosurg. 53 (1989) 29-39. 22. Kumar K., Nath R.K., and Toth C. : Spinal cord stimulation is effective in the management of reflex sympathetic dystrophy. Neurosurg. 40 (1997) 503-509. 23. Kemler M.A., Barendse G.A.M., Van Kleefe M., Van Den Wildenberg F.A.J.M., Weber W.E. : Electrical stimulation in of reflex sympathetic dystrophy: retrospective analysis of 23 patients. J. Neurosurg (Spine). 1 (1999) 79-83. 24. Kemlar MA, Barendse GA, Van Kleef M: Spinal cord stimulation in patients with chronic reflex sympathetic dystrophy. N Eng J Med 2000; 343: 618-624. References 25. Kemler MA, de Vet HCW, Barendse GAM, van den Wildenberg FAJM, van Kleef M, Spinal cord sitmulation for reflex sympathetic dystrophy – Five year follow-up, NEJM, 20006, 354, 2394-2396. 26. Cameron T: Safety and efficacy of spinal cord stimulation for the treatment of chronic pain: a 20 year literature review. J Neurosurg Spine 2004; 100: 254-267. 30. Manheimer C, Eliasson T, Augustinsson L: Electrical stimulation versus coronary artery bypass surgery in severe angina pectoris: the ESBY study. Circulation 1998; 97: 1157-1163. 31. Norsell H, Pihall M, Eliasson T, et al. :Effects of spinal cord stimulation and coronary artery bypass grafting on myocardial ischemia and heart rate variability: further results from the ESBY study. Cardiology 2000;94:12-18. 32. Eddicks S, Maier- Hauff K, et al :Thoracic spinal cord stimulation improves functional status and relieves symptoms in patients with refractory angina pectoris: the first placebo- controlled randomized study. Heart 2007; 93: 585- 590. References 33. DeJongste M.J.L., Hautvast R.W.M., Hillege H.L., and Lie K.L. : Efficacy of spinal cord stimulation as an adjuvant therapy of angina pectoris, A prospective randomized study. J. Am. Coll. Cardiol. 23 (1994) 1592-1597. 34. Di Pede F, Lanza GA, Zuin G, et al. Immediate and long term clinical outcome after spinal cord stimulation for refractory angina pectoris. Am J Cardiol 2003;91(8) 951- 955. 35. Vulink N., Overgaauw D., Jesserun G., TenVaarwerk I., Kropmans T., ven der Shans C., Middel B., Staal M., and DeJongste M : The effects of spinal cord stimulation on quality of life in patients with therapeutically chronic refractory angina pectoris. Neuromodulation 2 (1999) 33-40 36. Hautvast RW, DeJongste MJ, Staal MJ: Spinal cord stimulation in chronic intractable angina pectoris: a randomized, controlled efficacy study. Am Heart J 1998; 136: 1114-1120. 37. Manheimer C, Eliasson T, Augustinsson L: Electrical stimulation versus coronary artery bypass surgery in severe angina pectoris: the ESBY study. Circulation 1998; 97: 1157-1163. 38. Ekre O, Eliasson T, Norrsell H, et al. :Long term effets of spinal cord stimulation and coronary artery bypass grafting on quality of life and survival in the ESBY study. Eur Heart J 2002; 23:19381945. 39. Hautvast RW, Brouwer J, DeJongste MJ, Lie KI. Effect of spinal cord stimulation on heart rate variability and myocardial ischemia in patients with chronic intractable angina pectoris – a prospective ambulatory electrocardiographic study. Clin Cardiol 1998; 21: 33-38. 40. Thamer V., Deussen A., Schipke J.D., Tolle T., and Heush G. : Pain and myocardial ischemia:the role of the sympathetic system. Bas. Res. Card. 85s1 (1990) 253-266. References 41. Meller S.T. and Gebhart G.F. : A critical review of the afferent pathways and the potential chemical mediators involved in cardiac pain. Neurosc. 48 (1992) 501-24. 42. Hautvast RW, Blanksma PK, DeJongste MJ, Pruim J, van der Wall EE, Vaalburg W, Lie KI. Effect of spinal cord stimulation on myocardial blood flow assessed by positron emission tomography inpatients with refractory angina pectoris. Amer Jour Cardiol. 1996; 77(7):462-7. 43. Hirshberg RM, Al- Chaer ED, Lawand NB, Westlund KN, Willis WD. Is there a pathway in the posterior funiculus that signals visceral pain? Pain. 1996; 667:291-305. 44. Ceballos A, Cabezudo L, Bovaira M, Fenollosa P, Moro B. Spinal cord stimulation: a possible therapeutic alternative for chronic mesenteric ischemia. Pain. 2000; 87: 99-101. 45. Krames ES, Mousad DG. Spinal cord stimulation reverses pain and diarrheal episodes of irritable bowel syndrome: a case report. Neuromodulation. 2004;7:82-88. 46. Khan Y, Raza S, Khan E. Application of spinal cord stimulation for the treatment of abdominal visceral pain syndromes: case reports. Neuromodulation. 2005;8:14-27. 47. Tiede J, Ghazi S,Lamer T, Obray J. The use of spinal cord stimulation in refractory abdominal visceral pain: case reports and literature review. Pain practice 6(3): 197-202. 48. Kapural L, Narouze S, Janicki T, Mekhail N. Spinal cord stimulation is an effective treatment for the chronic intractable visceral pelvic pain. Pain Medicine 7(5): 440-443. References 49. Ness TJ, Gebhart GF. Visceral pain: a review of experimental studies. Pain 1990; 41: 167234. 50.Mitchell GAG. Anatomy of the autonomic nervous system. Edinburgh: E&S Livingstone; 1953