Occipital nerve stimulation for intractable chronic migraine

Evidence-based recommendations on occipital nerve stimulation for intractable chronic migraine. This involves using implanted electrodes to deliver electrical impulses to the occipital nerve to mask migraine pain.

# Guidance
The evidence on occipital nerve stimulation (ONS) for intractable chronic migraine shows some efficacy in the short term but there is very little evidence about longterm outcomes. With regard to safety, there is a risk of complications, needing further surgery. Therefore, this procedure should only be used with special arrangements for clinical governance, consent, and audit or research.
Clinicians wishing to undertake ONS for intractable chronic migraine should take the following actions:
Inform the clinical governance leads in their Trusts.
Ensure that patients understand the uncertainty about the procedure's safety and efficacy, and provide them with clear written information. In addition, the use of NICE's information for the public is recommended.
Selection of patients for treatment using ONS for intractable chronic migraine should be done by a multidisciplinary team, including specialists in headache, pain management and neurosurgery.
Clinicians should enter details about all patients undergoing ONS for intractable chronic migraine onto the UK Neuromodulation Register when access to that database is available. They should audit and review clinical outcomes locally and should document and consider their relationship to patient characteristics.
NICE encourages publication of further information from comparative studies and from collaborative data collection to guide future use of this procedure and to provide patients with the best possible advice. Publications should include full details of any complications, and of adjunctive or subsequent treatments. Outcomes should include measures of pain, function and quality of life, particularly in the long term.
NICE may review the procedure on publication of further evidence.# The procedure

# Indications and current treatments
Migraine is a severe headache, often accompanied by sensitivity to light and sound. It may be preceded by an aura, consisting of perception of an unusual light, an unpleasant smell or, occasionally, confusing thoughts or experiences. The International Classification of Headache Disorders (International Headache Society 2004) provides a classification of migraine types.
Current treatment for patients with migraine aims to prevent or stop episodes with drugs such as painkillers, antiemetics and triptans (as recommended in NICE clinical guideline 150). If these fail, invasive treatments such as nerve blocks, botulinum toxin type A (NICE technology appraisal guidance 260) or acupuncture are sometimes used.

# Outline of the procedure
ONS for intractable chronic migraine is usually done in 2 stages, although a singlestage procedure is sometimes used. In the first, trial stage, using local anaesthesia and usually with fluoroscopic guidance, electrodes are passed through a subcutaneous tunnel and placed over the occipital nerve(s) around the level of C1. Correct placement of electrodes is verified by intraoperative stimulation and patient feedback before they are sutured to subcutaneous tissue. A lead is tunnelled under the skin from the electrode to an exit site in the posterior cervical region, where it is connected by an external extension lead to a handheld neurostimulator.
The second stage is carried out if the trial is successful. With the patient under general anaesthesia, an implantable neurostimulator is secured in a subcutaneous pocket, usually in the infraclavicular region or the abdominal wall. A lead is tunnelled from the electrode to the implantable neurostimulator. The patient uses a remote control to stimulate the occipital nerves when needed.
Sections 2.3 and 2.4 describe efficacy and safety outcomes from the published literature that the Committee considered as part of the evidence about this procedure. For more detailed information on the evidence, see the systematic review and the addendum to the systematic review.

# Efficacy
A randomised controlled trial (RCT) of 157 patients compared ONS (active stimulation, n=105) against sham stimulation (n=52). It reported a statistically significantly greater decrease in the 'Migraine disability assessment score' (MIDAS), which takes into account headache days and their impact on the patient's life (maximum score 200), at 12week followup for the ONS group than for the sham stimulation group (64.6 and 20.4 reduction respectively, p=0.001).
An RCT of 67 patients comparing ONS (n=33) against sham stimulation (n=17) or medical management (n=17) reported a responder rate (defined as a reduction in headache days per month of 50% or more, or a 3point or greater reduction in average overall pain intensity compared with baseline at 3 months) of 39% (11/28) in the ONS group, 6% (1/16) in the sham stimulation group and 0% (0/17) in the medication group (p value not reported).
A case series of 25 patients reported that headache frequency per 90 days reduced from 75.56 (standard deviation  26.81) before implantation to 37.45 (SD 7.49) over a mean followup of 18 months (p<0.001).
The RCT of 157 patients reported no significant difference between the groups in the proportion of patients whose pain reduced by 50% or more (measured on a visual analogue scale) (17% for ONS and 14% for sham stimulation, p=0.55) at 12week followup.
The case series of 25 patients reported a significant reduction in headache severity (010 scale) from a baseline of 9.32 (SD 1.28) to 5.72 (SD 3.31) over a mean followup of 18 months (p<0.001).
The Specialist Advisers listed key efficacy outcomes as a reduction in migraine or headache days, headache severity, frequency and duration, disability score (measured by MIDAS), medication use and improvements in quality of life (SF36).

# Safety
Infections at the implant site were reported in 14% (7/51) of patients in the RCT of 67 patients at 3month followup. Infection was reported in 4% (4/105) of patients in the ONS group and 6% (3/52) of patients in the sham stimulation group in the RCT of 157 patients at 12week followup (no further details available).
Skin erosion was reported in 4% (4/105) of patients in the ONS group and 4% (2/52) of patients in the sham stimulation group in the RCT of 157 patients at 12week followup.
Lead migration or dislodgement was reported in 10% (5/52) of patients in the sham stimulation group and 14% (15/105) of patients in the ONS group in the RCT of 157 patients after 3 months; and in 24% (12/51) of patients in the RCT of 67 patients at 3month followup. Lead migration was reported in 36% (9/25) of patients in the case series of 25 patients at mean 18month followup.
Problems with ineffective device programming and ineffective leads were reported in 12% (6/51) and 4% (2/51) of patients respectively, in the RCT of 67 patients at 3month followup.
Persistent pain or numbness at the implant site was reported in 13% (14/105) of patients in the ONS group and 17% (9/52) of patients in the sham stimulation group in the RCT of 157 patients at 12week followup. Loss of motor or musculoskeletal control was reported in 1% (1/105) of patients in the ONS group in the same RCT (timing not reported).
Unintended stimulation effect (no further details available) was reported in 6% (6/105) of patients in the ONS group and 2% (1/52) of patients in the sham stimulation group in the RCT of 157 patients.
In addition to the above, the Specialist Advisers listed haemorrhage, nerve damage and lead fracture as theoretical adverse events.

# Other comments
The Committee recognised that patients being considered for ONS for intractable chronic migraine commonly have very distressing and longterm symptoms that other methods of treatment have failed to control.
The Committee recognised that research in this area is difficult because there is uncertainty about the percentage level of relief that should be considered significant and it is difficult to achieve blinding in trials, and because of the complex and heterogeneous nature of chronic migraine. Currently, there are not enough goodquality comparative studies to be able confidently to evaluate the procedure's efficacy. This underpins the recommendations in section 1.
The Committee recognised that techniques and technology are evolving and, implicitly, this may produce better results.# Further information
For related NICE guidance, see the NICE website.

# Information for patients
NICE has produced information on this procedure for patients and carers (Information for the public). It explains the nature of the procedure and the guidance issued by NICE, and has been written with patient consent in mind.# About this guidance
NICE interventional procedure guidance makes recommendations on the safety and efficacy of the procedure. It does not cover whether or not the NHS should fund a procedure. Funding decisions are taken by local NHS bodies after considering the clinical effectiveness of the procedure and whether it represents value for money for the NHS. It is for healthcare professionals and people using the NHS in England, Wales, Scotland and Northern Ireland, and is endorsed by Healthcare Improvement Scotland for implementation by NHSScotland.
This guidance was developed using the NICE interventional procedures guidance process.
We have produced a summary of this guidance for patients and carers.
Your
    responsibility
    This guidance represents the views of NICE and was arrived at after careful consideration of the available evidence. Healthcare professionals are expected to take it fully into account when exercising their clinical judgement. This guidance does not, however, override the individual responsibility of healthcare professionals to make appropriate decisions in the circumstances of the individual patient, in consultation with the patient and/or guardian or carer.
Implementation of this guidance is the responsibility of local commissioners and/or providers. Commissioners and providers are reminded that it is their responsibility to implement the guidance, in their local context, in light of their duties to have due regard to the need to eliminate unlawful discrimination, advance equality of opportunity and foster good relations. Nothing in this guidance should be interpreted in a way that would be inconsistent with compliance with those duties.
Copyright
     National Institute for Health and Care Excellence, 2013. All rights reserved. NICE copyright material can be downloaded for private research and study, and may be reproduced for educational and notforprofit purposes. No reproduction by or for commercial organisations, or for commercial purposes, is allowed without the written permission of NICE.
Contact
    NICE
    National Institute for Health and Care ExcellenceLevel 1A, City Tower, Piccadilly Plaza, Manchester M1 4BT
www.nice.org.uk
nice@nice.org.uk
ISBN 9781473100992