Peripheral nerve stimulation to treat chronic painful syndromes

Freitas, Tiago da Silva; Paiva, Alessandra Vasconcelos da Silva; Ogliari, Kátia Crys Moura; Godoy, Lucas Garcia de Souza; Valente, Fernanda Albernaz

doi:10.1590/S1806-00132013000400016

Abstracts

BACKGROUND AND OBJECTIVES: Peripheral nerve stimulation to treat chronic pain is a neurosurgical armamentarium used for a long time, being indicated to treat neuropathic painful syndromes together with other types of nerve stimulation: dorsal column electric stimulation and deep cerebral stimulation. This study aimed at analyzing the relevance of peripheral nerve stimulation to treat chronic painful syndromes. CONTENTS: Primary indication is severe chronic neuropathic pain refractory to conservative treatment. However, the affected area needs to have a defined anatomic distribution and related to the peripheral nerve to be stimulated. One should also notice signs of objective involvement of the nerve. A nerve stimulation test shall be performed from 7 to 10 days prior to the final implant and pain must improve at least 50% according to specific evaluation scales. There are two methods to implant electrodes in peripheral nerves: direct surgical approach and percutaneous technique. After the test, the implant with permanent generator is performed. CONCLUSION: Peripheral nerve stimulation to treat chronic painful syndromes has shown promising results. The development of new materials is extremely necessary for the technical evolution and treatment of chronic painful syndromes. In this sense, new prostheses are being developed and one feature of a more feasible implant to be used in the peripheral nervous system would be low profile prosthesis with already implanted and rechargeable battery.

Chronic neuropathic pain; Chronic painful syndrome; Pain evaluation scales; Peripheral nerve stimulation

JUSTIFICATIVA E OBJETIVOS: O uso da estimulação elétrica de nervos periféricos para o tratamento da dor crônica constitui um armamentário neurocirúrgico utilizado há bastante tempo, sendo uma modalidade indicada no tratamento das síndromes dolorosas de caráter neuropático, juntamente com outras formas de neuroestimulação: estimulação elétrica da coluna dorsal e a estimulação cerebral profunda. O objetivo deste estudo foi analisar a relevância da estimulação nervosa periférica no tratamento das síndromes dolorosas crônicas. CONTEÚDO: A principal indicação é a dor neuropática crônica, intensa, refratária ao tratamento conservador. Apresenta, contudo, necessidade de a área acometida ter uma distribuição anatômica definida e relacionada ao nervo periférico no qual se deseja realizar a estimulação. Deve-se perceber também sinais de comprometimentoobjetivo do nervo. É necessária a realização de teste de neuroestimulação entre 7 e 10 dias previamente ao implante definitivo e deve-se obter melhora de pelo menos 50% da dor em escalas de avaliação específicas. Existem duas formas de implante de eletrodo em nervos periféricos: abordagem cirúrgica direta e técnica percutânea. Após o teste ser completado, é realizado o implante do sistema de gerador permanente. CONCLUSÃO: O uso da estimulação de nervos periféricos no tratamento das síndromes dolorosas crônicas tem mostrado resultados promissores. O desenvolvimento de novos materiais é extremamente necessário para a evolução da técnica e o tratamento dessas síndromes dolorosas crônicas. Nesse sentido, novas próteses estão sendo desenvolvidas e uma das características de implante mais viável para uso no sistema nervoso periférico seria uma prótese de baixo perfil, com bateria já implantada com os eletrodos e recarregável.

Dor neuropática crônica; Escalas de avaliação da dor; Estimulação nervosa periférica; Síndrome dolorosa crônica

REVIEW ARTICLE

Peripheral nerve stimulation to treat chronic painful syndromes^*

Tiago da Silva Freitas^I; Alessandra Vasconcelos da Silva Paiva^II; Kátia Crys Moura Ogliari^II; Lucas Garcia de Souza Godoy^II; Fernanda Albernaz Valente^II

^IUniversity Hospital of Brasília, Base Hospital of Federal District, Pain Institute of Brasília, Brasília, DF, Brazil

^IISuperior School of Health Sciences, Brasília, DF, Brazil

Correspondence to

ABSTRACT

BACKGROUND AND OBJECTIVES: Peripheral nerve stimulation to treat chronic pain is a neurosurgical armamentarium used for a long time, being indicated to treat neuropathic painful syndromes together with other types of nerve stimulation: dorsal column electric stimulation and deep cerebral stimulation. This study aimed at analyzing the relevance of peripheral nerve stimulation to treat chronic painful syndromes.

CONTENTS: Primary indication is severe chronic neuropathic pain refractory to conservative treatment. However, the affected area needs to have a defined anatomic distribution and related to the peripheral nerve to be stimulated. One should also notice signs of objective involvement of the nerve. A nerve stimulation test shall be performed from 7 to 10 days prior to the final implant and pain must improve at least 50% according to specific evaluation scales. There are two methods to implant electrodes in peripheral nerves: direct surgical approach and percutaneous technique. After the test, the implant with permanent generator is performed.

CONCLUSION: Peripheral nerve stimulation to treat chronic painful syndromes has shown promising results. The development of new materials is extremely necessary for the technical evolution and treatment of chronic painful syndromes. In this sense, new prostheses are being developed and one feature of a more feasible implant to be used in the peripheral nervous system would be a low profile prosthesis with already implanted and rechargeable battery.

Keywords: Chronic neuropathic pain, Chronic painful syndrome, Pain evaluation scales, Peripheral nerve stimulation.

INTRODUCTION

Peripheral nerve stimulation to treat chronic pain is a neurosurgical armamentarium used for a long time, being indicated for neuropathic pain syndromes together with other nerve stimulation methods: dorsal column electric stimulation (CES) and deep brain stimulation (DBS). Historically, peripheral nervous system (PNS) electric stimulation to treat pain dates from antiquity¹, but it was with the publication of the Gate Theory by Melzack & Wall in 1965 that appeared a new idea about peripheral circuits function and that several experiments with electric stimulation have become feasible to treat chronic pain syndromes.

Although several aspects of the gate theory pathophysiology have succumbed, this theory provided the scientific basis for peripheral nerve stimulation to treat chronic pain: the stimulation of large fibers activated with lower threshold as compared to small fibers, at enough intensity to produce paresthesia, should also relieve pain².

The first experiments with peripheral nerve stimulation were published in 1967^3,4when infraorbital foramen was stimulated in eight patients who presented significant pain improvement while the stimulation was working. Authors have also suggested in this study the idea of an implantable stimulator. At the same time, a study was started about dorsal column nerve stimulation with early results leading to the development of implantable systems, being the first battery-powered system developed by Cordis in 1976 (cited for Rossi)⁵.

In following years, several studies were carried out using peripheral nerve stimulation^6-21. Unfortunately, early results of such studies were not very promising: in 1976 a global improvement rate of 26% was reported. In 1982, the reported success rate was 53%¹⁴.

Due to described results, to reports of peripheral nerve injury by the placement of the electrode and the broader dissemination of dorsal column stimulation to treat chronic pain syndromes, peripheral nerve stimulation has become less attractive. This was also reflected in the development of specific devices for peripheral nerve stimulation, which were very restricted, with just one device approved by the Food and Drug Administration (FDA).

Peripheral nerve stimulation to treat chronic pain reappeared with a study describing a technique of percutaneous implant of electrodes in the occipital nerve to treat occipital neuralgia. Several studies have followed using stimulation both for occipital nerves and the combined use in supraorbital branches to treat chronic migraine headache and other autonomic headaches^23-29. From then on, reports on the use of implants in trigeminal nerves³⁰, their use to control post hernia repair chronic pain (inguinal nerve), and the use of paraspinal electrodes to treat post-herpetic neuralgia, sacroiliitis and coccydynea have returned to PNS stimulation to treat chronic neuropathic pain syndromes^31-34.

INDICATIONS

They follow the same patterns of spinal neuromodulation having as major indication chronic severe neuropathic pain affecting patients' functionality and refractory to conservative treatment (drugs, physiotherapy, local anesthetic and sympathetic blocks, transcutaneous electric stimulation, botulinum toxin, etc.)^19-21. However, the affected area has to be a well defined anatomical area and related to the peripheral nerve where stimulation is to be performed. One should also notice signs of objective peripheral nerve involvement (hypoesthesia, hyperpathia, hyperesthesia, allodynia, etc.)^19-21.

Confirmation of the respective "target" nerve involvement through local anesthetic block is a stage often recommended by the literature²¹; however, there are no evidences that such parameter is a factor for better prognosis.

Nerve stimulation test before the definitive implant through externalization of electrodes is mandatory. It is performed in a specific period (between 7 and 10 days) and there shall be pain improvement of at least 50% according to specific pain evaluation scales^19-21.

Specific indications

A- Post-herpetic neuralgia;

B- Post-traumatic neuropathic pain;

C- Postoperative neuropathic pain;

D- Facial neuropathic pain;

E- Clinically untreatable occipital neuralgia or occipital cervicogenic pain;

F- Transformed migraines with continuous occipital and hemicranial pain;

G- Complex regional pain syndrome;

H- Cluster headache.

CONTRAINDICATIONS

They encompass: use of anticoagulants or patients with coagulation disorders, patients with active infection on probable surgical area, patients with major cognitive problems, untreatable depression or with neuropsychological evaluation indicating major personality disorder¹⁹.

Another contraindication is patient needing routine follow up with MRI due to the limitations of these exams with such materials²¹.

SURGICAL TECHNIQUE

General aspects

Electrode implant follows well-defined recommendations. There are basically two types of peripheral nerve implants: direct surgical approach, involving direct nerve exposure and placement of "plaque" electrodes on the nerve to one side or on both sides ("Sandwich" technique). Optionally, the electrode may be placed by the percutaneous technique through a needle inserted perpendicularly to the nerve pathway.

Types of electrodes are:

For the percutaneous technique, cylindrical electrodes with 4 or 8 poles are used: Pisces-Quad Compact, Pisces-Quad, Octad, Quad plus or Quad Compact from Medtronic or Quattrode, Octrode from ANS/St. Jude.

For the open surgical technique plaque electrodes with 4, 8 or 16 poles are used: Resume, Resume II, On-Point PNS, Resume TL, Specify, Specify 2x8 from Medtronic or the models Lamitrode S4, Lamitrode 44C, Lamitrode S8, Lamitrode 88C from ANS/St. Jude.

For both techniques, it is critical to adequately anchor the electrode to prevent migrations and shifts. Depending on the technique, this may be done in the entry area of the electrode (for example, by the percutaneous occipital nerve stimulation technique) or through direct fixation of the electrode in subcutaneous and fascia/periosteum planes in open incisions.

The implant protocol requires pain control efficacy test. So, after the implant, the electrode has to be tunneled and connected to an external test extensor associated to an external generator. It is important to assure, before pain evaluation, that the painful area is covered with the sensation of paresthesias/numbness. Painful area coverage may be tested in the intraoperative or immediate postoperative period. During the test period, patients are usually covered with antimicrobials (although their use does not demonstrably decrease the chance of infection).

After test completion (mean of 7 to 10 days), the permanent generator system is implanted in the operating center, under general anesthesia, because the insertion of subcutaneous tunnelers is painful. Most frequent implant sites are gluteus region, abdominal wall or infraclavicular region. Regardless of the chosen site, final generator implant site shall be deep enough to avoid bedsores and shall be located in reduced mobility regions (Figures 1 and 2).

Specific aspects of percutanous implants

Occipital, supraorbital and infraorbital nerve implant:

Electrodes are almost routinely inserted under radioscopy. There are parameters for implants placement: infraorbital foramen and orbit base for the infraorbital nerve, limit and supraorbital foramen for the supraorbital nerve, C1 arch and midline for occipital nerve.

Electrodes may be placed from medial to lateral or vice-versa, depending on surgeon's experience. Electrodes with 4, 8 or 16 contacts may be used, crossing below the epifascial plane but above the muscles. Electrode placement pattern should cross the sense of the nerve for it to be stimulated by at least two electrode contacts.

Trigeminal nerve implant

The electrode is inserted by Hartel's tecnique³⁵, crossing the oval foramen, under radioscopy. It is then tunneled and fixed by its entry hole to the skin, being taken subcutaneously to the masseter and subauricular region.

RESULTS

With regard to neuropathic pain syndromes (regional complex pain syndrome, traumatic or postoperative neuropathy), most studies show 50% improvement in pain scales for an average of 60-70% of patients submitted to the procedure with follow-up of more than 3 years^36,37.

For percutaneous stimulation for facial pain syndromes, results are similar to those described above, especially for occipital neuralgia, with 50% improvement in pain scales for an average of 65% of patients with follow-up from 1 month to 3 years³⁰.

There are several new indications for peripheral nerves stimulation: cluster headache, migraine, daily chronic headache and fibromyalgia³⁸. Preliminary results were:

Migraine

A case series involving occipital nerve stimulation was reported in 2003²³. Eighty-eight percent of patients had 50% decrease in pain scales and incidence of headache.

A retrospective case series described in 2007²⁴ has shown 8 patients treated with occipital nerve stimulation in 3 years followup. There has been more than 50% improvement in pain scales for half the patients.

The first study including a control group in the ONSTIM²⁵. The occipital stimulation group had improvement in 39% of patients in a 3-month follow-up. Other prospective, randomized and controlled occipital nerve stimulation studies have been produced, however still without published results.

Hemicrania continua

A case series with six patients submitted to occipital nerve stimulation has been described. Four out of six patients had more than 50% improvement in pain scales²⁶.

Cluster headache

Two prospective studies with 8 patients each were published. In the first²⁷, stimulation was unilateral and 5 out of 8 patients had more than 50% decrease in the frequency of crises. In the second group, stimulation was bilateral and only three patients had this level of improvement.

A case series with four patients was described using bilateral occipital stimulation to treat cluster headache²⁸. These patients were followed-up for six months and two had more than 50% improvement in severity and number of headache crises.

Combined supraorbital and occipital nerves stimulation

Migraine

A case series with seven patients was described in the literature²⁹. Six out of seven patients have reported 90 to 100% decrease in pain scales and five had no need for drugs in a follow-up of up to 35 months.

CONCLUSION

Peripheral nerves stimulation to treat chronic pain syndromes has shown promising results. The development of new materials, better adapted to peripheral nerve stimulation, with low profile, is extremely needed for the development of the technique and the management of these chronic pain syndromes. In addition, new prostheses are being developed and one feature of a more feasible implant to be used in the PNS would be a low profile prosthesis with rechargeable battery already implanted with the electrodes.

REFERENCES

1. Beck AH. The Flexner report and the standardization of Americcan medical education. JAMA. 2004;291(17):2139-40.
2. Melzack R, Wall PD. Pain mechanisms: a new theory. Science. 1965;150(3699):971-9.
3. Wall PD, Sweet WH. Temporary abolition of pain in man. Science. 1967;155(3758):108-9.
4. White JC, Sweet WH. Pain and the neurosurgeon: a forty-year experience. Springfield IL: Thomas; 1969: 894-9p.
5. Rossi U. The history of electrical stimulation of the nervous system for the control of pain. In: Simpson BA, (editor), Electrical Stimulation and relief of Pain. Amsterdam: Elsevier; 2003. 5-16p.
6. Cauthen JC, Renner EJ. Transcutaneous and peripheral nerve stimulation for chronic pain states. Surg Neurol. 1975;4(1):102-4.
7. Kirsch WM, Lewis JA, Simon RH. Experiences with electrical stimulation devices for the control of chronic pain. Med Instrum. 1975;9(5):217-20.
8. Picaza JA, Cannon BW, Hunter SE, Boyd AS, Guma J, Maurer D. Pain suppression by peripheral nerve stimulation: Part II. Observations with implanted devices. Surg Neurol. 1975;4(1):115-26.
9. Campbell JN, Long DM. Peripheral nerve stimulation in the treatment of intractable pain. J Neurosurg. 1976;45(6):692-9.
10. Sweet WH. Control of pain by direct stimulation of peripheral nerves. Clin Neurosurg. 1976;23:103-11.
11. Nashold BS Jr, Mullen JB, Avery R. Peripheral nerve stimulation for pain relief using a multicontact electrode system. Technical note. J Neurosurg. 1979;51(6):872-3.
12. Law JD, Sweet J, Kirsch WM. Retrospective analysis of 22 patients with chronic pain treated by peripheral nerve stimulation. J Neurosurg. 1980;52(4):482-5.
13. Long DM, Erickson D, Campbell J, North R. Electrical stimulation of the spinal cord and peripheral nerves for pain control: a 10-year experience. Appl Neurophysiol. 1981;44(4):207-17.
14. Nashold BS Jr, Goldner JL, Mullen JB, Bright DS. Long-term pain control by direct peripheral- nerve stimulation. J Bone Joint Surg Am. 1982;64(1):1-10.
15. Waisbrod H, Panhans C, Hansen D, Gerbershagen HU. Direct nerve stimulation for painful peripheral neuropathies. J Bone Joint Surg Br. 1985;67(3):470-2.
16. Long DM. Stimulation of the peripheral nervous system for pain control. Clin Neurosurg. 1986;33:323-43.
17. Iacono RP, Linford J, Sandyk R. Pain management after lower extremity amputation. Neurosurgery. 1987;20(3):496-500.
18. Racz GB, Browne T, Lewis R Jr. Peripheral stimulator implant for treatment of causalgia caused by electrical burns. Tex Med. 1988;84(11):45-50.
19. Heavner JE, Racz G, Diede JM. Peripheral nerve stimulation: current concepts. In: Waldman SD, Winnie AP, (editors). Interventional pain management, 1^st ed. Philadelphia: WB. Saunders; 1996. p. 423-5.
20. Hassenbusch SJ, Stanton-Hicks M, Schoppa D, Walsh JG, Covington EC. Long-term results of peripheral nerve stimulation for reflex sympathetic dystrophy. J Neurosurg. 1996;84(3):415-23.
21. Stanton-Hicks M, Salamon J. Stimulation of the central and peripheral nervous system for the control of pain. J Clin Neurophysiol. 1997;14(1):46-62.
22. Weiner RL, Reed KL. Peripheral neurostimulation for control of intractable occipital neuralgia. Neuromodulation. 1999;2(3):217-21.
23. Popeney CA, Aló KM. Peripheral neurostimulation for the treatment of chronic, disabling transformed migraine. Headache. 2003;43(4):369-75.
24. Schwedt TJ, Dodick DW, Hentz J, Trentman TL, Zimmerman RS. Occipital nerve stimulation for chronic headache--long-term safety and efficacy. Cephalalgia. 2007;27(2):153-7.
25. Saper JR, Dodick DW, Silberstein SD, McCarville S, Sun M, Goadsby PJ; OSTIM Investigators. Occipital nerve stimulation for the treatment of intractable chronic migraine headache: ONSTIM feasibility study. Cephalalgia. 2011;31(3):271-85.
26. Burns BL, Watkins L, Goadsby PJ. Treatment of hemicrania continua by occipital nerve stimulation with a bion device: long-term follow-up of a crossover study. Lancet Neurol. 2008;7(11):1001-12.
27. Burns B, Watkins L, Goadsby PJ. Treatment of medically intractable cluster headache by occipital nerve stimulation: long-term follow-up of eight patients. Lancet. 2007;369(9567):1099-106.
28. de Quintana-Schmidt C, Casajuana-Garreta E, Molet-Teixidó J, García-Bach M, Roig C, Clavel-Laria P, et al. Stimulation of the occipital nerve in the treatment of drug-resistant cluster headache. Rev Neurol. 2010;51(1):19-26. Spanish.
29. Reed KL, Black SB, Banta CJ 2nd, Will KR. Combined occipital and supraorbital neurostimulation for the treatment of chronic migraine headaches: initial experience.Cephalalgia, 2010;30(3):260-71.
30. Slavin KV, Burchiel KJ. Use of long-term nerve stimulation with implanted electrodes in the treatment of intractable craniofacial pain. J Neurosurg. 2000;92:576.
31. Stinson LW Jr, Roderer GT, Cross NE, Davis BE. Peripheral subcutaneous electrostimulation for control of intractable post-operative inguinal pain: a case report series. Neuromodulation. 2001;4(3):99-104.
32. Paicius RM, Bernstein CA, Lempert-Cohen C. Peripheral nerve field stimulation for the treatment of chronic low back pain: preliminary results of long-term follow-up: a case series. Neuromodulation. 2007;10(3):279-90.
33. Yakovlev AE, Peterson AT. Peripheral nerve stimulation in treatment of intractable postherpetic neuralgia. Neuromodulation. 2007;10(4):373-5.
34. Kothari S. Neuromodulatory approaches to chronic pelvic pain and coccygodynia. Acta Neurochir Suppl 2007;97(Pt 1):365-71.
35. Hartel F. Die Leitungsanãsthesie und Injektionsbehanlung des Ganglion Gasseri und der Trigemenisstãne Arch Klin Chir, 1912;100:193-292.
36. Eisenberg E, Waisbrod H, Gerbeshagen HU. Long term peripheral nerve stimulation for painful nerve injuries. Clin J Pain. 2004;20(3):143-6.
37. Thimineur M, De Ridder D. C2 area neurostimulation: a surgical treatment for fibromyalgia. Pain Med. 2007;8(8):639-46.
38. Magis D, Allena M, Bolla M, De Pasqua V, Remacle JM, Schoenen J. Occipital nerve stimulation for drug-resistant chronic cluster headache: a prospective pilot study. Lancet Neurol 2007;6(4):314-21.

Endereço para correspondência:

Alessandra Vasconcelos da Silva Paiva

SGAN 912 MD D Bloco D Un. 120 - Ed. Park Ville

70790-120 Brasília, DF, Brasil

E-mail:

alevasconcelospaiva@gmail.com

*

Recebido do Hospital Universitário de Brasília, Brasília, DF, Brasil.

Publication Dates

Publication in this collection
04 Feb 2014
Date of issue
Dec 2013

History

Received
05 Apr 2013
Accepted
02 July 2013

This work is licensed under a Creative Commons Attribution 4.0 International License.

[1] 1. Beck AH. The Flexner report and the standardization of Americcan medical education. JAMA. 2004;291(17):2139-40.

[2] 2. Melzack R, Wall PD. Pain mechanisms: a new theory. Science. 1965;150(3699):971-9.

[3] 3. Wall PD, Sweet WH. Temporary abolition of pain in man. Science. 1967;155(3758):108-9.

[4] 4. White JC, Sweet WH. Pain and the neurosurgeon: a forty-year experience. Springfield IL: Thomas; 1969: 894-9p.

[5] 5. Rossi U. The history of electrical stimulation of the nervous system for the control of pain. In: Simpson BA, (editor), Electrical Stimulation and relief of Pain. Amsterdam: Elsevier; 2003. 5-16p.

[6] 6. Cauthen JC, Renner EJ. Transcutaneous and peripheral nerve stimulation for chronic pain states. Surg Neurol. 1975;4(1):102-4.

[7] 7. Kirsch WM, Lewis JA, Simon RH. Experiences with electrical stimulation devices for the control of chronic pain. Med Instrum. 1975;9(5):217-20.

[8] 8. Picaza JA, Cannon BW, Hunter SE, Boyd AS, Guma J, Maurer D. Pain suppression by peripheral nerve stimulation: Part II. Observations with implanted devices. Surg Neurol. 1975;4(1):115-26.

[9] 9. Campbell JN, Long DM. Peripheral nerve stimulation in the treatment of intractable pain. J Neurosurg. 1976;45(6):692-9.

[10] 10. Sweet WH. Control of pain by direct stimulation of peripheral nerves. Clin Neurosurg. 1976;23:103-11.

[11] 11. Nashold BS Jr, Mullen JB, Avery R. Peripheral nerve stimulation for pain relief using a multicontact electrode system. Technical note. J Neurosurg. 1979;51(6):872-3.

[12] 12. Law JD, Sweet J, Kirsch WM. Retrospective analysis of 22 patients with chronic pain treated by peripheral nerve stimulation. J Neurosurg. 1980;52(4):482-5.

[13] 13. Long DM, Erickson D, Campbell J, North R. Electrical stimulation of the spinal cord and peripheral nerves for pain control: a 10-year experience. Appl Neurophysiol. 1981;44(4):207-17.

[14] 14. Nashold BS Jr, Goldner JL, Mullen JB, Bright DS. Long-term pain control by direct peripheral- nerve stimulation. J Bone Joint Surg Am. 1982;64(1):1-10.

[15] 15. Waisbrod H, Panhans C, Hansen D, Gerbershagen HU. Direct nerve stimulation for painful peripheral neuropathies. J Bone Joint Surg Br. 1985;67(3):470-2.

[16] 16. Long DM. Stimulation of the peripheral nervous system for pain control. Clin Neurosurg. 1986;33:323-43.

[17] 17. Iacono RP, Linford J, Sandyk R. Pain management after lower extremity amputation. Neurosurgery. 1987;20(3):496-500.

[18] 18. Racz GB, Browne T, Lewis R Jr. Peripheral stimulator implant for treatment of causalgia caused by electrical burns. Tex Med. 1988;84(11):45-50.

[19] 19. Heavner JE, Racz G, Diede JM. Peripheral nerve stimulation: current concepts. In: Waldman SD, Winnie AP, (editors). Interventional pain management, 1^st ed. Philadelphia: WB. Saunders; 1996. p. 423-5.

[20] 20. Hassenbusch SJ, Stanton-Hicks M, Schoppa D, Walsh JG, Covington EC. Long-term results of peripheral nerve stimulation for reflex sympathetic dystrophy. J Neurosurg. 1996;84(3):415-23.

[21] 21. Stanton-Hicks M, Salamon J. Stimulation of the central and peripheral nervous system for the control of pain. J Clin Neurophysiol. 1997;14(1):46-62.

[22] 22. Weiner RL, Reed KL. Peripheral neurostimulation for control of intractable occipital neuralgia. Neuromodulation. 1999;2(3):217-21.

[23] 23. Popeney CA, Aló KM. Peripheral neurostimulation for the treatment of chronic, disabling transformed migraine. Headache. 2003;43(4):369-75.

[24] 24. Schwedt TJ, Dodick DW, Hentz J, Trentman TL, Zimmerman RS. Occipital nerve stimulation for chronic headache--long-term safety and efficacy. Cephalalgia. 2007;27(2):153-7.

[25] 25. Saper JR, Dodick DW, Silberstein SD, McCarville S, Sun M, Goadsby PJ; OSTIM Investigators. Occipital nerve stimulation for the treatment of intractable chronic migraine headache: ONSTIM feasibility study. Cephalalgia. 2011;31(3):271-85.

[26] 26. Burns BL, Watkins L, Goadsby PJ. Treatment of hemicrania continua by occipital nerve stimulation with a bion device: long-term follow-up of a crossover study. Lancet Neurol. 2008;7(11):1001-12.

[27] 27. Burns B, Watkins L, Goadsby PJ. Treatment of medically intractable cluster headache by occipital nerve stimulation: long-term follow-up of eight patients. Lancet. 2007;369(9567):1099-106.

[28] 28. de Quintana-Schmidt C, Casajuana-Garreta E, Molet-Teixidó J, García-Bach M, Roig C, Clavel-Laria P, et al. Stimulation of the occipital nerve in the treatment of drug-resistant cluster headache. Rev Neurol. 2010;51(1):19-26. Spanish.

[29] 29. Reed KL, Black SB, Banta CJ 2nd, Will KR. Combined occipital and supraorbital neurostimulation for the treatment of chronic migraine headaches: initial experience.Cephalalgia, 2010;30(3):260-71.

[30] 30. Slavin KV, Burchiel KJ. Use of long-term nerve stimulation with implanted electrodes in the treatment of intractable craniofacial pain. J Neurosurg. 2000;92:576.

[31] 31. Stinson LW Jr, Roderer GT, Cross NE, Davis BE. Peripheral subcutaneous electrostimulation for control of intractable post-operative inguinal pain: a case report series. Neuromodulation. 2001;4(3):99-104.

[32] 32. Paicius RM, Bernstein CA, Lempert-Cohen C. Peripheral nerve field stimulation for the treatment of chronic low back pain: preliminary results of long-term follow-up: a case series. Neuromodulation. 2007;10(3):279-90.

[33] 33. Yakovlev AE, Peterson AT. Peripheral nerve stimulation in treatment of intractable postherpetic neuralgia. Neuromodulation. 2007;10(4):373-5.

[34] 34. Kothari S. Neuromodulatory approaches to chronic pelvic pain and coccygodynia. Acta Neurochir Suppl 2007;97(Pt 1):365-71.

[35] 35. Hartel F. Die Leitungsanãsthesie und Injektionsbehanlung des Ganglion Gasseri und der Trigemenisstãne Arch Klin Chir, 1912;100:193-292.

[36] 36. Eisenberg E, Waisbrod H, Gerbeshagen HU. Long term peripheral nerve stimulation for painful nerve injuries. Clin J Pain. 2004;20(3):143-6.

[37] 37. Thimineur M, De Ridder D. C2 area neurostimulation: a surgical treatment for fibromyalgia. Pain Med. 2007;8(8):639-46.

[38] 38. Magis D, Allena M, Bolla M, De Pasqua V, Remacle JM, Schoenen J. Occipital nerve stimulation for drug-resistant chronic cluster headache: a prospective pilot study. Lancet Neurol 2007;6(4):314-21.