Clinical Correspondence
Occipital nerve block prior to occipital nerve stimulation for refractory chronic migraine and chronic cluster headache: Myth or prediction?
Cephalalgia 2015, Vol. 35(4) 359–362 ! International Headache Society 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0333102414541685 cep.sagepub.com
Thomas M Kinfe1,2, Patrick Schuss2 and Hartmut Vatter2 Abstract Background: Occipital nerve stimulation (ONS) results in beneficial outcomes, with marked pain relief, in otherwise intractable chronic migraine (CM) and chronic cluster headache (CCH). Some studies have reported that a positive response to occipital nerve block (ONB) administered prior to ONS predicts a positive response to ONS. However, other studies concerned with proper patient selection claimed no predictive value for ONB. The aim of this study was to re-evaluate the usefulness and predictive value of ONB prior to ONS. Methods: Literature searches on the predictive value of ONB were performed in MEDLINE and PubMed. Patient data were extracted and a pooled analysis was performed. Results: The literature review revealed 133 patients with CM and seven patients with CCH who received preoperative ONB. To date, a randomized controlled study examining the relationship between ONB and ONS has not been conducted in patients with CM. Conclusions: Current literature suggests that ONB does not sufficiently predict ONS responsiveness in patients with refractory CM and CCH; this important issue requires further investigation. Keywords Occipital nerve stimulation, occipital nerve block, chronic migraine, chronic cluster headache, intractable pain Date received: 12 February 2014; revised: 2 April 2014; 25 May 2014; accepted: 9 June 2014
Abbreviations CM: chronic migraine; CCH: chronic cluster headache; ONB: occipital nerve block; ONS: occipital nerve stimulation; ICHD: International Classification of Headache Disorders; ONSTIM: occipital nerve stimulation for the treatment of intractable chronic migraine headache
Introduction The potential value of occipital nerve stimulation (ONS) as a safe and effective treatment modality for otherwise intractable chronic migraine (CM) and chronic cluster headache (CCH) has been described in several randomized controlled trials and a small number of open-label case series (1–6). Selection of patients with CM and CCH who are eligible for ONS remains difficult, leading to intensive investigation dealing with responsiveness following presurgical occipital
nerve block (ONB). Despite the minimally invasive, adjustable nature of ONS and the development of standardized diagnostic and therapeutic guidelines (7), ONS remains an expensive treatment tool. Recent literature reports different recommendations and results showing that presurgical ONB response can be a positive or negative predictor of ONS response (1,2,4,8–10). The aim of this article was to re-evaluate the predictive value of ONB administered prior to ONS in patients 1
Division of Functional Neurosurgery and Neuromodulation, Rheinische Friedrich Wilhelms University, Bonn, Germany 2 Department of Neurosurgery, Rheinische Friedrich Wilhelms University, Bonn, Germany Corresponding author: Thomas Kinfe, Division of Functional Neurosurgery and Neuromodulation, Department of Neurosurgery, Rheinische Friedrich Wilhelms University, Sigmund-Freudstreet 25, Bonn 53127, Germany. Email: [email protected]
360
Cephalalgia 35(4)
with CM and CCH by reviewing relevant published, peer-reviewed data.
ONS implantation from the 1999 to the present literature.
Methods
CM and ONB
An electronic search was performed in PubMed and MEDLINE using the following terms: trigeminal autonomic headache, trigeminal, chronic migraine, chronic cluster headache, intractable headache, occipital nerve stimulation, occipital nerve block, and prediction. Both types of headache were investigated and were defined according to the International Classification of Headache Disorders, second edition (ICHD-II). Articles published between 1999 and the present were evaluated. Studies that fully or partially analyzed the predictive value of ONB prior to ONS implantation were included. Most of the reviewed literature and supporting references dealt with patients having comorbidities, in addition to CM or CCH. Our search focused on patients with CM and CCH who were eligible for ONS and who had received ONB previously, in order to scrutinize the conventional view of ONB being predictive for ONS response. After obtaining full text versions of all studies, patient data regarding response rate to ONB, and subsequent ONS, were independently extracted and verified by two authors (TMK and PS). Individual patient data extracted from the included studies were pooled for further analysis. Data analysis was performed using SPSS (version 21, IBM Corp, Armonk, NY, USA). Categorical variables were analyzed in contingency tables using Fisher’s exact test. Results of p < 0.05 were considered statistically significant (Table 1).
We retrospectively analyzed data of 133 patients with CM in this study. In their 1999 breakthrough publication, Weiner and Reed (8) clearly described the predictive value of ONB in a cohort of 13 patients (secondarily classified as 12 cases of CM and one case of hemicrania continua). They found an overall response rate of 100% for ONB and ONS. In a follow-up study, this response rate was revised to 80%, with 12 patients responding to ONB. In a later, single-center trial, three of 10 patients with chronic refractory headache received local anesthetic/ corticosteroid injections, which elicited partial responses, whereupon all patients were implanted with a peripheral nerve stimulator; it is difficult to make clear predictive statements from this study. In a similar study, Schwedt et al. (10) found no correlation between ONB response and ONS-induced pain relief. Of seven patients with CM, five responded to ONB, of whom three did not benefit from ONS. Interestingly, but confusingly, of the two patients who did not respond to ONB, one experienced significant pain suppression following ONS. The only existing multicenter, randomized, blinded, controlled feasibility study (Occipital Nerve Stimulation for the Treatment of Chronic Migraine Headache, ONSTIM) included 110 patients with CM and reported an ONB responder rate of 68% (75/110). After three months, the ONS responder rate dropped to 39%, again indicating no predictive value of the ONB procedure in this setting (Table 1). Interestingly, the ONSTIM study contained an ‘‘ancillary group’’ of eight patients who failed to respond to ONB; six of these patients received ONS. Their response rate, evaluated in five patients at the three-month follow-up, reached 40%. Our pooled analysis of extracted patient data upheld the statement by Saper and colleagues (2) confirming no predictive validity for ONB in patients with CM.
Results In total, 133 patients with CM and seven patients with CCH were identified to have received ONB prior to
Table 1. Pooled CM patient data extracted from studies included in the systemic review. ONB responder n ¼ 45
Weiner et al. 1999 Saper et al. 2011 Schwedt et al. 2007
ONS responder n ¼ 25a
ONS nonresponder n ¼ 20a
12 11 2
– 17 3
CM: chronic migraine; ONB: occipital nerve block; ONS: occipital nerve stimulation. ap ¼ 1.0 indicating no significant prediction.
CCH and ONB It was a significant challenge to find a sufficient number of identified cases from the literature that were examined for a correlation between ONB and ONS for CCH. Several open-label studies have attempted to validate the therapeutic potential of ONS, with current, promising data showing a high level of pain relief following ONS. However, the use of subcutaneous local anesthetics/corticosteroids has been trialed for prediction in only a small number of patients (seven CCH).
361
Kinfe et al. Both positive and negative correlations were found; therefore, no clear conclusion can be derived from the current data.
Discussion In the past, ablative surgical procedures, including radiofrequency, rhizotomy of the Gasserian ganglion or trigeminal nerve, and resection of the nervus petrosus superficialis or ganglion sphenopalatinum have been used to treat headache. However, technical progress has led to the use of new neuromodulatory techniques, such as ONS. These techniques are minimally invasive and allow stimulation to be adapted to the time course of the underlying chronic and refractory headache syndrome (8). The mode of action of ONB of the greater/minor occipital nerve is not yet fully understood. It is hypothesized that ONB decreases trigeminal hyperexcitability and/or diminishes nociceptive transmission through modulation of vasoactive neuropeptides, such as substance P and calcitonin gene-related peptide (10,11). Electrical stimulation of the large, afferent, occipital nerve fibers during ONS leads to presynaptic suppression of the small nociceptive and A-d fibers known to be involved in pain perception. In addition, ONS may alter cerebral blood flow in brain structures related to pain perception and processing (10). The anatomical convergence of afferent fibers of the upper cervical segment C1– 3 with fibers of the trigeminal nucleus caudalis may explain the effects of ONS and ONB observed in patients with CM and CCH. While ONB primarily induces a quick, short-term suppression of headache, electrical stimulation of the occipital nerves is thought to act over a longer time period, modulating the suprasegmental anatomical structures responsible for central pain processing. Thus, ONB responsiveness may be processed at a peripheral/segmental level, while the effects of ONS, in addition to segmental modifications, may be the realm of central pain-processing structures. This hypothesis underlines the dominant role of central and suprasegmental components in chronic headache syndromes. When assessing the efficacy of neuromodulatory approaches for treatment of refractory chronic headache syndromes, it is important to consider the placebo effect. A fast and positive response to ONB may lead to an enhanced placebo effect, indicating ONS responsiveness. However, this does not appear to be the case as, in general, a negative ONB trial will not suspend ONS success. Thus, one can argue in favor of true efficacy of electrical stimulation approaches, such as ONS. The ONSTIM study clearly demonstrated a negative correlation between ONB response and subsequent ONS response. Although the study described an ONB response of 68%, not more than 39% of patients
benefited from subsequent implantation of ONS devices (2). A further analysis of the ‘‘ancillary group’’ at a threemonth follow-up (including eight patients defined as ONB failures) revealed a response rate of 40% in five patients who received a neuromodulatory device (of the three other patients: one rescinded, one experienced intraoperative failure, and one showed insufficient efficacy after one month). Although only a small number, the ONS responders in the ancillary group may be indicative of the favorable, true efficacy of ONS. In our opinion, this suggests that ONB should not be used as a preoperative patient selection tool for patients with CM, as the multicenter controlled-randomized design of the ONSTIM study is more reliable than the smaller CM/ONS open-label case series that established ONB’s predictive capability (2,8). Trials assessing the value of ONB as a presurgical selection procedure in patients with CCH have even smaller numbers of participants, and an open-label character, that make it difficult to draw firm conclusions. To enhance pre-existing patient selection guidelines for ONS, the use of ONB, involving injection of amino amide-type anesthetics (e.g. lidocaine and bupivacaine) and corticosteroids into the region of the occipital nerve prior to ONS has been investigated (8–10). These studies have resulted in conflicting recommendations; while some regard ONB as a useful, predictive pre-implantation methodology for identifying suitable candidates (8), others have described a negative correlation between ONB response and ONS success (1,2,4,10). A wide range of applied techniques can be used to perform ONB, and several recommendations related to these techniques, such as choice of anesthetic, with or without an accompanying steroid, have been made; this may lead to variability in ONB outcomes. Pharmacokinetic interaction with medications prescribed for existing comorbidities may also influence ONB success, resulting in difficulty in interpreting clinical outcomes. Unless evidence-based interpretation of results becomes possible, contrary ONB responders, who fail to show similar outcomes following ONS, and ONB failures, who subsequently achieve sustained pain suppression following ONS, will continue to be reported (10).
Conclusions In summary, the potential predictive role of ONB in CCH and other chronic intractable headache syndromes remains unclear. This must be considered in detail when identifying suitable candidates for neuromodulatory therapy, and further investigation is required. In patients with CM, ONB responsiveness may not be helpful in predicting subsequent ONS response. Therefore, well-conducted studies are warranted and are currently in progress.
362
Cephalalgia 35(4)
Clinical implications . Predictive value of occipital nerve block (ONB) in promoting proper patient selection. . Therapeutical impact for neuromodulation for the treatment of chronic intractable headache syndromes. . The mode of action of ONB and occipital nerve stimulation remains unclear. Funding The authors received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors for this study.
Conflict of interest
5.
6.
TMK works as a consultant for St Jude Medical Inc and for Medtronic Inc. 7.
References 1. Lipton R, Goadsby P, Cady R, et al. PRISM study: Occipital nerve stimulation for treatment-refractory migraine. Cephalalgia 2009; 29: 30. 2. Saper JR, Dodick DW, Silberstein SD, et al. Occipital nerve stimulation for the treatment of intractable chronic migraine headache: ONSTIM feasibility study. Cephalalgia 2011; 31: 271–285. 3. Tronnier V and Rasche D. Subkutane periphere Stimulation des N. occipitalis major zur Behandlung chronischer Kopfschmerzsyndrome [Subcutaneous peripheral stimulation of the greater occipital nerve for the treatment of chronic headache syndromes] [article in German]. Schmerz 2010; 24: 441–448. 4. Silberstein S, Dodick D, Saper J, et al. Safety and efficacy of peripheral nerve stimulation of the occipital nerves for the management of chronic migraine: Results from
8.
9.
10.
11.
a randomized, multicenter, double-blinded, controlled study. Cephalalgia 2012; 32: 1165–1179. Burns B, Watkins L and Goadsby PJ. Treatment of intractable chronic cluster headache by occipital nerve stimulation in 14 patients. Neurology 2009; 72: 341–345. Magis D, Gerardy PY, Remacle JM, et al. Sustained effectiveness of occipital nerve stimulation in drug-resistant chronic cluster headache. Headache 2011; 51: 1191–1201. Martelletti P, Jensen RH, Antal A, et al. Neuromodulation of chronic headaches: Position statement from the European Headache Federation. J Headache Pain 2013; 14: 86. Weiner RL and Reed KL. Peripheral neurostimulation for control of intractable occipital neuralgia. Neuromodulation 1999; 2: 217–222. Palmeleire K, Van Buyten JP, Van Buynder M, et al. Phenotype of patients responsive to occipital nerve stimulation for refractory head pain. Cephalalgia 2010; 30: 662–673. Schwedt TJ, Dodick DW and Trentman TL. Response to occipital nerve block is not useful in predicting efficacy of occipital nerve stimulation. Cephalalgia 2007; 27: 271–274. Levin M. Nerve blocks in the treatment of headache. Neurotherapeutics 2010; 7: 197–203.
Occipital nerve block prior to occipital nerve stimulation for refractory chronic migraine and chronic cluster headache: Myth or prediction?
Cephalalgia 2015, Vol. 35(4) 359–362 ! International Headache Society 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0333102414541685 cep.sagepub.com
Thomas M Kinfe1,2, Patrick Schuss2 and Hartmut Vatter2 Abstract Background: Occipital nerve stimulation (ONS) results in beneficial outcomes, with marked pain relief, in otherwise intractable chronic migraine (CM) and chronic cluster headache (CCH). Some studies have reported that a positive response to occipital nerve block (ONB) administered prior to ONS predicts a positive response to ONS. However, other studies concerned with proper patient selection claimed no predictive value for ONB. The aim of this study was to re-evaluate the usefulness and predictive value of ONB prior to ONS. Methods: Literature searches on the predictive value of ONB were performed in MEDLINE and PubMed. Patient data were extracted and a pooled analysis was performed. Results: The literature review revealed 133 patients with CM and seven patients with CCH who received preoperative ONB. To date, a randomized controlled study examining the relationship between ONB and ONS has not been conducted in patients with CM. Conclusions: Current literature suggests that ONB does not sufficiently predict ONS responsiveness in patients with refractory CM and CCH; this important issue requires further investigation. Keywords Occipital nerve stimulation, occipital nerve block, chronic migraine, chronic cluster headache, intractable pain Date received: 12 February 2014; revised: 2 April 2014; 25 May 2014; accepted: 9 June 2014
Abbreviations CM: chronic migraine; CCH: chronic cluster headache; ONB: occipital nerve block; ONS: occipital nerve stimulation; ICHD: International Classification of Headache Disorders; ONSTIM: occipital nerve stimulation for the treatment of intractable chronic migraine headache
Introduction The potential value of occipital nerve stimulation (ONS) as a safe and effective treatment modality for otherwise intractable chronic migraine (CM) and chronic cluster headache (CCH) has been described in several randomized controlled trials and a small number of open-label case series (1–6). Selection of patients with CM and CCH who are eligible for ONS remains difficult, leading to intensive investigation dealing with responsiveness following presurgical occipital
nerve block (ONB). Despite the minimally invasive, adjustable nature of ONS and the development of standardized diagnostic and therapeutic guidelines (7), ONS remains an expensive treatment tool. Recent literature reports different recommendations and results showing that presurgical ONB response can be a positive or negative predictor of ONS response (1,2,4,8–10). The aim of this article was to re-evaluate the predictive value of ONB administered prior to ONS in patients 1
Division of Functional Neurosurgery and Neuromodulation, Rheinische Friedrich Wilhelms University, Bonn, Germany 2 Department of Neurosurgery, Rheinische Friedrich Wilhelms University, Bonn, Germany Corresponding author: Thomas Kinfe, Division of Functional Neurosurgery and Neuromodulation, Department of Neurosurgery, Rheinische Friedrich Wilhelms University, Sigmund-Freudstreet 25, Bonn 53127, Germany. Email: [email protected]
360
Cephalalgia 35(4)
with CM and CCH by reviewing relevant published, peer-reviewed data.
ONS implantation from the 1999 to the present literature.
Methods
CM and ONB
An electronic search was performed in PubMed and MEDLINE using the following terms: trigeminal autonomic headache, trigeminal, chronic migraine, chronic cluster headache, intractable headache, occipital nerve stimulation, occipital nerve block, and prediction. Both types of headache were investigated and were defined according to the International Classification of Headache Disorders, second edition (ICHD-II). Articles published between 1999 and the present were evaluated. Studies that fully or partially analyzed the predictive value of ONB prior to ONS implantation were included. Most of the reviewed literature and supporting references dealt with patients having comorbidities, in addition to CM or CCH. Our search focused on patients with CM and CCH who were eligible for ONS and who had received ONB previously, in order to scrutinize the conventional view of ONB being predictive for ONS response. After obtaining full text versions of all studies, patient data regarding response rate to ONB, and subsequent ONS, were independently extracted and verified by two authors (TMK and PS). Individual patient data extracted from the included studies were pooled for further analysis. Data analysis was performed using SPSS (version 21, IBM Corp, Armonk, NY, USA). Categorical variables were analyzed in contingency tables using Fisher’s exact test. Results of p < 0.05 were considered statistically significant (Table 1).
We retrospectively analyzed data of 133 patients with CM in this study. In their 1999 breakthrough publication, Weiner and Reed (8) clearly described the predictive value of ONB in a cohort of 13 patients (secondarily classified as 12 cases of CM and one case of hemicrania continua). They found an overall response rate of 100% for ONB and ONS. In a follow-up study, this response rate was revised to 80%, with 12 patients responding to ONB. In a later, single-center trial, three of 10 patients with chronic refractory headache received local anesthetic/ corticosteroid injections, which elicited partial responses, whereupon all patients were implanted with a peripheral nerve stimulator; it is difficult to make clear predictive statements from this study. In a similar study, Schwedt et al. (10) found no correlation between ONB response and ONS-induced pain relief. Of seven patients with CM, five responded to ONB, of whom three did not benefit from ONS. Interestingly, but confusingly, of the two patients who did not respond to ONB, one experienced significant pain suppression following ONS. The only existing multicenter, randomized, blinded, controlled feasibility study (Occipital Nerve Stimulation for the Treatment of Chronic Migraine Headache, ONSTIM) included 110 patients with CM and reported an ONB responder rate of 68% (75/110). After three months, the ONS responder rate dropped to 39%, again indicating no predictive value of the ONB procedure in this setting (Table 1). Interestingly, the ONSTIM study contained an ‘‘ancillary group’’ of eight patients who failed to respond to ONB; six of these patients received ONS. Their response rate, evaluated in five patients at the three-month follow-up, reached 40%. Our pooled analysis of extracted patient data upheld the statement by Saper and colleagues (2) confirming no predictive validity for ONB in patients with CM.
Results In total, 133 patients with CM and seven patients with CCH were identified to have received ONB prior to
Table 1. Pooled CM patient data extracted from studies included in the systemic review. ONB responder n ¼ 45
Weiner et al. 1999 Saper et al. 2011 Schwedt et al. 2007
ONS responder n ¼ 25a
ONS nonresponder n ¼ 20a
12 11 2
– 17 3
CM: chronic migraine; ONB: occipital nerve block; ONS: occipital nerve stimulation. ap ¼ 1.0 indicating no significant prediction.
CCH and ONB It was a significant challenge to find a sufficient number of identified cases from the literature that were examined for a correlation between ONB and ONS for CCH. Several open-label studies have attempted to validate the therapeutic potential of ONS, with current, promising data showing a high level of pain relief following ONS. However, the use of subcutaneous local anesthetics/corticosteroids has been trialed for prediction in only a small number of patients (seven CCH).
361
Kinfe et al. Both positive and negative correlations were found; therefore, no clear conclusion can be derived from the current data.
Discussion In the past, ablative surgical procedures, including radiofrequency, rhizotomy of the Gasserian ganglion or trigeminal nerve, and resection of the nervus petrosus superficialis or ganglion sphenopalatinum have been used to treat headache. However, technical progress has led to the use of new neuromodulatory techniques, such as ONS. These techniques are minimally invasive and allow stimulation to be adapted to the time course of the underlying chronic and refractory headache syndrome (8). The mode of action of ONB of the greater/minor occipital nerve is not yet fully understood. It is hypothesized that ONB decreases trigeminal hyperexcitability and/or diminishes nociceptive transmission through modulation of vasoactive neuropeptides, such as substance P and calcitonin gene-related peptide (10,11). Electrical stimulation of the large, afferent, occipital nerve fibers during ONS leads to presynaptic suppression of the small nociceptive and A-d fibers known to be involved in pain perception. In addition, ONS may alter cerebral blood flow in brain structures related to pain perception and processing (10). The anatomical convergence of afferent fibers of the upper cervical segment C1– 3 with fibers of the trigeminal nucleus caudalis may explain the effects of ONS and ONB observed in patients with CM and CCH. While ONB primarily induces a quick, short-term suppression of headache, electrical stimulation of the occipital nerves is thought to act over a longer time period, modulating the suprasegmental anatomical structures responsible for central pain processing. Thus, ONB responsiveness may be processed at a peripheral/segmental level, while the effects of ONS, in addition to segmental modifications, may be the realm of central pain-processing structures. This hypothesis underlines the dominant role of central and suprasegmental components in chronic headache syndromes. When assessing the efficacy of neuromodulatory approaches for treatment of refractory chronic headache syndromes, it is important to consider the placebo effect. A fast and positive response to ONB may lead to an enhanced placebo effect, indicating ONS responsiveness. However, this does not appear to be the case as, in general, a negative ONB trial will not suspend ONS success. Thus, one can argue in favor of true efficacy of electrical stimulation approaches, such as ONS. The ONSTIM study clearly demonstrated a negative correlation between ONB response and subsequent ONS response. Although the study described an ONB response of 68%, not more than 39% of patients
benefited from subsequent implantation of ONS devices (2). A further analysis of the ‘‘ancillary group’’ at a threemonth follow-up (including eight patients defined as ONB failures) revealed a response rate of 40% in five patients who received a neuromodulatory device (of the three other patients: one rescinded, one experienced intraoperative failure, and one showed insufficient efficacy after one month). Although only a small number, the ONS responders in the ancillary group may be indicative of the favorable, true efficacy of ONS. In our opinion, this suggests that ONB should not be used as a preoperative patient selection tool for patients with CM, as the multicenter controlled-randomized design of the ONSTIM study is more reliable than the smaller CM/ONS open-label case series that established ONB’s predictive capability (2,8). Trials assessing the value of ONB as a presurgical selection procedure in patients with CCH have even smaller numbers of participants, and an open-label character, that make it difficult to draw firm conclusions. To enhance pre-existing patient selection guidelines for ONS, the use of ONB, involving injection of amino amide-type anesthetics (e.g. lidocaine and bupivacaine) and corticosteroids into the region of the occipital nerve prior to ONS has been investigated (8–10). These studies have resulted in conflicting recommendations; while some regard ONB as a useful, predictive pre-implantation methodology for identifying suitable candidates (8), others have described a negative correlation between ONB response and ONS success (1,2,4,10). A wide range of applied techniques can be used to perform ONB, and several recommendations related to these techniques, such as choice of anesthetic, with or without an accompanying steroid, have been made; this may lead to variability in ONB outcomes. Pharmacokinetic interaction with medications prescribed for existing comorbidities may also influence ONB success, resulting in difficulty in interpreting clinical outcomes. Unless evidence-based interpretation of results becomes possible, contrary ONB responders, who fail to show similar outcomes following ONS, and ONB failures, who subsequently achieve sustained pain suppression following ONS, will continue to be reported (10).
Conclusions In summary, the potential predictive role of ONB in CCH and other chronic intractable headache syndromes remains unclear. This must be considered in detail when identifying suitable candidates for neuromodulatory therapy, and further investigation is required. In patients with CM, ONB responsiveness may not be helpful in predicting subsequent ONS response. Therefore, well-conducted studies are warranted and are currently in progress.
362
Cephalalgia 35(4)
Clinical implications . Predictive value of occipital nerve block (ONB) in promoting proper patient selection. . Therapeutical impact for neuromodulation for the treatment of chronic intractable headache syndromes. . The mode of action of ONB and occipital nerve stimulation remains unclear. Funding The authors received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors for this study.
Conflict of interest
5.
6.
TMK works as a consultant for St Jude Medical Inc and for Medtronic Inc. 7.
References 1. Lipton R, Goadsby P, Cady R, et al. PRISM study: Occipital nerve stimulation for treatment-refractory migraine. Cephalalgia 2009; 29: 30. 2. Saper JR, Dodick DW, Silberstein SD, et al. Occipital nerve stimulation for the treatment of intractable chronic migraine headache: ONSTIM feasibility study. Cephalalgia 2011; 31: 271–285. 3. Tronnier V and Rasche D. Subkutane periphere Stimulation des N. occipitalis major zur Behandlung chronischer Kopfschmerzsyndrome [Subcutaneous peripheral stimulation of the greater occipital nerve for the treatment of chronic headache syndromes] [article in German]. Schmerz 2010; 24: 441–448. 4. Silberstein S, Dodick D, Saper J, et al. Safety and efficacy of peripheral nerve stimulation of the occipital nerves for the management of chronic migraine: Results from
8.
9.
10.
11.
a randomized, multicenter, double-blinded, controlled study. Cephalalgia 2012; 32: 1165–1179. Burns B, Watkins L and Goadsby PJ. Treatment of intractable chronic cluster headache by occipital nerve stimulation in 14 patients. Neurology 2009; 72: 341–345. Magis D, Gerardy PY, Remacle JM, et al. Sustained effectiveness of occipital nerve stimulation in drug-resistant chronic cluster headache. Headache 2011; 51: 1191–1201. Martelletti P, Jensen RH, Antal A, et al. Neuromodulation of chronic headaches: Position statement from the European Headache Federation. J Headache Pain 2013; 14: 86. Weiner RL and Reed KL. Peripheral neurostimulation for control of intractable occipital neuralgia. Neuromodulation 1999; 2: 217–222. Palmeleire K, Van Buyten JP, Van Buynder M, et al. Phenotype of patients responsive to occipital nerve stimulation for refractory head pain. Cephalalgia 2010; 30: 662–673. Schwedt TJ, Dodick DW and Trentman TL. Response to occipital nerve block is not useful in predicting efficacy of occipital nerve stimulation. Cephalalgia 2007; 27: 271–274. Levin M. Nerve blocks in the treatment of headache. Neurotherapeutics 2010; 7: 197–203.
