monic lesion is known to be the dorsal horn, it is better to believe its role to be in partial control of the origin of the pain. The basic pain mechanism of PHN is known to originate from both the central and peripheral nervous systems. The central mechanism is a disinhibition of the large afferent (Aβ) fibers, central reorganization, and cen- tral sensitization. The peripheral mechanism is ectopic discharge, increased sympathetic activity and catechol- amines on the sensitized and damaged primary afferents, and continuous inflammatory response of the sensory nerve or nervi nervorum [19]. 　　The great limitation of this study was the small num- ber of patients. A well-designed comparative prospective multi-center studies are needed. The other limitation is the control ability of the SCS instrument because of old age. Only the patients know characteristics and intensity of the pain; however, they will not or cannot manipulate the mode of the SCS. It is difficult to use the SCS even with the best mode of control. Therefore, SCS in the elderly may be underestimated. It is also difficult to perform SCS trial test for pain in the subacute stage of PHN due to insurance coverage. 　　SCS was helpful in managing with tolerable pain levels in some PHN patients with CKD along with tolerable neu- ropathic medications for over 2 years. ACKNOWLEDGEMENTS This study was supported by Medical Institute of Pusan National University Yangsan Hospital. REFERENCES 1. Sampathkumar P, Drage LA, Martin DP. Herpes zoster (shingles) and postherpetic neuralgia. Mayo Clin Proc 2009; 84: 274-80. 2. Lee JH, Park SK, Lee DI, Jung JK, Lim HK, Cha YD. Assessment of the quality of postherpetic neuralgia related Korean internet sites. Korean J Pain 2009; 22: 141-5. 3. Sim WS, Choi JH, Han KR, Kim YC. Treatment of herpes zoster and postherpetic neuralgia. Korean J Pain 2008; 21: 93-105. 4. Choe H, Han YJ. A clinical study on the treatment of postherpetic neuralgia. J Korean Pain Soc 1990; 3: 131-8. 5. Kim HK, Kim ST, Jung JW, Keoun JY, Kim IS, Chung KS. Lower level laser therapy on postherpetic neuralgia. J Korean IY Beak, et al / SCS for PHN in Patients with CKD 157 Pain Soc 1992; 5: 258-62. 6. Lee DI, Kim DO, Kim KS, Kwon MI, Shin KI, Kang WJ. Gabapentin for the treatment of postherpetic neuralgia. J Korean Pain Soc 1999; 12: 188-90. 7. Lee JH, Kim TY, Ha SH, Kwon YE, Yoon CS. Pulsed radiofrequency lesioning of supraorbital and supratrochlear nerve in postherpetic neuralgia: a report of 2 cases. J Korean Pain Soc 2004; 17: 239-42. 8. Kim WY, Moon DE, Choi JH, Park CM, Han SM, Kim SH. The effect of spinal cord stimulation in patients with complex regional pain syndrome. Korean J Pain 2006; 19: 152-8. 9. Kim YJ, Kim MH, Lim SH, Lee JH, Lee KM, Cheong SH, et al. Treatment of tremor and spasticity in failed back surgery syndrome with spinal cord stimulation: a case report. Korean J Pain 2006; 19: 107-10. 10. Costantini A. Spinal cord stimulation. Minerva Anestesiol 2005; 71: 471-4. 11. Kim YC, Kim SH, Cho JY, Hong JH. Cervical spinal cord stimulation using an 8 electrode lead in a patient with complex regional pain syndrome type I: a case report. Korean J Pain 2007; 20: 186-9. 12. Benzon HT, Chekka K, Darnule A, Chung B, Wille O, Malik K. Evidence-based case report: the prevention and management of postherpetic neuralgia with emphasis on interventional procedures. Reg Anesth Pain Med 2009; 34: 514-21. 13. Kumar K, Toth C, Nath RK. Spinal cord stimulation for chronic pain in peripheral neuropathy. Surg Neurol 1996; 46: 363-9. 14. Harke H, Gretenkort P, Ladleif HU, Koester P, Rahman S. Spinal cord stimulation in postherpetic neuralgia and in acute herpes zoster pain. Anesth Analg 2002; 94: 694-700. 15. Iseki M, Morita Y, Nakamura Y, Ifuku M, Komatsu S. Efficacy of limited-duration spinal cord stimulation for subacute postherpetic neuralgia. Ann Acad Med Singapore 2009; 38: 1004-6. 16. Meglio M, Cioni B, Prezioso A, Talamonti G. Spinal cord stimulation (SCS) in the treatment of postherpetic pain. Acta Neurochir Suppl (Wien) 1989; 46: 65-6. 17. Kouroukli I, Neofytos D, Panaretou V, Zompolas V, Papastergiou D, Sanidas G, et al. Peripheral subcutaneous stimulation for the treatment of intractable postherpetic neuralgia: two case reports and literature review. Pain Pract 2009; 9: 225-9. 18. Upadhyay SP, Rana SP, Mishra S, Bhatnagar S. Successful treatment of an intractable postherpetic neuralgia (PHN) using peripheral nerve field stimulation (PNFS). Am J Hosp Palliat Care 2010; 27: 59-62. 19. Kim C. Pathophysiology of postherpetic neuralgia. J Korean Pain Soc 2004; 17(Suppl): 13-6.