Sarah Miller

Greater occipital nerve blocks in chronic cluster headache: a prospective open-label study

Greater occipital nerve blockade (GONB) has been shown to be effective in episodic cluster headache. However, its use in chronic cluster headache (CCH) is less certain. The study aims to prospectively assess the efficacy and consistency of response to GONB in a large series of CCH patients.

The red ear syndrome

Red Ear Syndrome (RES) is a very rare disorder, with approximately 100 published cases in the medical literature. Red ear (RE) episodes are characterised by unilateral or bilateral attacks of paroxysmal burning sensations and reddening of the external ear. The duration of these episodes ranges from a few seconds to several hours. The attacks occur with a frequency ranging from several a day to a few per year. Episodes can occur spontaneously or be triggered, most frequently by rubbing or touching the ear, heat or cold, chewing, brushing of the hair, neck movements or exertion. Early-onset idiopathic RES seems to be associated with migraine, whereas late-onset idiopathic forms have been reported in association with trigeminal autonomic cephalalgias (TACs). Secondary forms of RES occur with upper cervical spine disorders or temporo-mandibular joint dysfunction. RES is regarded refractory to medical treatments, although some migraine preventative treatments have shown moderate benefit mainly in patients with migraine-related attacks. The pathophysiology of RES is still unclear but several hypotheses involving peripheral or central nervous system mechanisms have been proposed.

Neurostimulation in the treatment of primary headaches

There is increasing interest in using neurostimulation to treat headache disorders. There are now several non-invasive and invasive stimulation devices available with some open-label series and small controlled trial studies that support their use. Non-invasive stimulation options include supraorbital stimulation (Cefaly), vagus nerve stimulation (gammaCore) and single-pulse transcranial magnetic stimulation (SpringTMS). Invasive procedures include occipital nerve stimulation, sphenopalatine ganglion stimulation and ventral tegmental area deep brain stimulation. These stimulation devices may find a place in the treatment pathway of headache disorders. Here, we explore the basic principles of neurostimulation for headache and overview the available methods of neurostimulation.

Treatment of intractable chronic cluster headache by occipital nerve stimulation: a cohort of 51 patients

Chronic cluster headache is a rare, highly disabling primary headache condition. When medically intractable, occipital nerve stimulation can offer effective treatment. Open‐label series have provided data on small cohorts only.

Predictors of response to occipital nerve stimulation in refractory chronic headache

Background Occipital nerve stimulation is a promising treatment for refractory chronic headache disorders, but is invasive and costly. Identifying predictors of response would be useful in selecting patients. We present the results of an open-label prospective cohort study of 100 patients (35 chronic migraine, 33 chronic cluster headache, 20 short-lasting unilateral neuralgiform headache attacks and 12 hemicrania continua) undergoing occipital nerve stimulation, using a multivariate binary regression analysis to identify predictors of response. Results Response rate of the cohort was 48%. Multivariate analysis showed short lasting unilateral neuralgiform headache attacks (OR 6.71; 95% CI 1.49–30.05; pu2009=u20090.013) and prior response to greater occipital nerve block (OR 4.22; 95% CI 1.35–13.21; pu2009=u20090.013) were associated with increased likelihood of response. Presence of occipital pain (OR 0.27; 95% CI 0.09–0.76; pu2009=u20090.014) and the presence of severe anxiety and/or depression (as measured on hospital anxiety and depression score) at time of implantation (OR 0.32; 95% CI 0.11–0.91; pu2009=u20090.032) were associated with reduced likelihood of response. Conclusion Possible clinical predictors of response to occipital nerve stimulation for refractory chronic headaches have been identified. Our data shows that those with short-lasting unilateral neuralgiform headache attacks respond better than those with chronic migraine, and that a prior response to greater occipital nerve block is associated with positive outcomes. This study suggests that the presence of occipital pain and severe mood disorder at time of implant are both associated with poor outcomes to occipital nerve stimulation.

DEEP BRAIN STIMULATION IN INTRACTABLE SHORT-LASTING UNILATERAL NEURALGIFORM HEADACHE ATTACKS: A MULTICASE SERIES

Introduction SUNCT and SUNA are primary headache conditions characterized by short lasting attacks of unilateral pain accompanied by autonomic features. Neuroimaging studies have suggested a role of the posterior hypothalamus in its pathogenesis. Aim Previous case reports on deep brain stimulation (DBS) of the midbrain tegmentum (just posterior to the hypothalamus) for SUNCT/SUNA are limited to a total of three patients. We present clinical data on eight new patients treated with DBS. Method Eight patients underwent midbrain tegmentum DBS with an MRI-guided and verified approach. The target lay between the mammillothalamic tract and the anteromedial quadrant of the red nucleus. Headache diaries were used to monitor response. Results The median follow up period was 20 months. Median improvement in attack frequency was 70%. Seven patients obtained a 30% or more reduction in attack frequency at final follow up. At final follow up, one patient had the stimulator off. Seven out of eight patients would opt to have the stimulator again and all would recommend to others. Conclusion Midbrain tegmentum DBS may be a useful treatment in intractable SUNCT. It should be reserved only for patients failing all other medical and surgical treatment options.

OCCIPITAL NERVE STIMULATION IN HIGHLY REFRACTORY CHRONIC HEADACHES: IDENTIFICATION OF POSSIBLE PREDICTORS OF SUCCESS

Introduction Occipital nerve stimulation (ONS) appears a promising treatment for refractory headaches. The procedure is invasive and response rates vary between studies. Identification of clinical predictors of outcome is therefore of importance. Aim To prospectively assess the efficacy of ONS in a cohort of intractable headache patients and identify clinical predictors of response. Methods 165 patients undergoing ONS at a single centre were studied. Headache load was calculated at baseline and final follow-up. A positive response was defined as a 30% reduction in headache load. A multivariate logistic regression analysis was carried out to identify predictors of outcome. Results Patient group was highly refractory at baseline. At a mean follow up of 40 months the response rate of the group was 50%. Clinical factors identified with an increased likelihood of response were co-existent chronic migraine and chronic cluster and the presence of non-headache related pain disorders. Occipital pain was associated with a reduced likelihood of response. Adverse event rates were favourable. Conclusion ONS is a potentially useful and safe treatment in refractory chronic headache disorders. The presence of multiple pain syndromes appears associated with increased likelihood of response and presence of occipital pain with a reduced likelihood.

AUDIT OF HEADACHE REFERRALS FROM PRIMARY CARE TO A REGIONAL HEADACHE SERVICE

Introduction Headache is the most common neurological symptom with which patients attend their GPs and is also the commonest reason for referral to neurology outpatient clinics. The Neurological Services Task and Finish Group in Scotland have developed various pathways for headache using SIGN and NHS Quality Improvement Scotland headache standards. Since 2011 management of chronic headache is also a QOF/QP criteria for general practitioners in Greater Glasgow & Clyde health board. Despite the wide distribution of pathways and the presence of QOF guidelines in primary care, referral practice would appear to be unchanged. The aim of this audit was to look at headache referrals to a specialist headache unit in Greater Glasgow and Clyde and compare it to available local QOF guidelines. Methods From the 1st June 2012–30th June 2012, data was collected from GP referral letters to obtain the number of referrals for headache, reason for referral, gender, duration of headache, acute treatments given for headache and investigations carried out prior to referral. Data collected was compared to current local QOF guidelines and referral pathways. Results A total of 133 patient referral letters were received from primary care during the four week period. Most referrals were routine (122; 91.7%) and there were 11 (8.3%) urgent referrals. Majority of the referrals were for treatment 65 (48.9%) of the headache disorder. The commonest referral diagnosis was migraine 73 (54.9%). There were more females 99 (74.4%) compared to males 34 (25.6%). Patients had complained of headaches for more than 2 years (60; 45.1%), <6 months (30; 22.6%), 1–2 years 17 (12.8%) and <12 months 13 (9.8%). At time of referral almost half (62, 46.6%) were deemed to have medication overuse headache by the vetting Neurologist but only one patient had had an attempt at stopping their overused medications prior to referral. Majority of patients were on prophylactic medication 76 (57.1%) for their headache disorder but when data was compared to current guidelines for referral, only 3 patients (2.3%) matched the criteria for referral for migraine. 34 (25%) patients had had neuroimaging studies done prior to referral. Conclusion The majority of referrals to the regional specialist headache service in Glasgow do not follow the referral guidelines. Following this audit an ‘enhanced vetting’ process has been put into place for headache referrals to the unit. The results of this audit was presented at QOF meetings for primary care in August–September 2012 and a repeat audit would be conducted in June 2013.