[Chronic migraine]. / Chronische Migräne.

The classification of the International Headache Society (IHS) generally differentiates episodic from chronic headache. Chronic migraine is defined as headache on 15 and more days a month over more than 3 months and headache on 8 days or more fulfils the criteria for migraine or were triptan/ergot-responsive when thought to be migrainous in early stages of the attack. The prevalence of chronic migraine is estimated at 2-4 %. The quality of life is highly compromised in this condition and comorbidities are much more frequent compared to episodic migraine. Data from prospective randomized studies are scarce as most patients with chronic migraine were excluded from previous trials and only few studies were conducted for this condition. The efficacy for prophylactic treatment compared with placebo is proven for topiramate and onabotulinum toxin A.

[Update on trigeminal autonomic cephalalgia]. / Neues zu trigeminoautonomen Kopfschmerzen.

Cluster headache, paroxysmal hemicrania and short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT syndrome) are classified under trigeminal autonomic cephalalgia (TAC). The proposed revision of the international classification of headache disorders (ICDH-3 beta) adds hemicrania continua to this diagnostic group. Moreover, diagnostic criteria of the other TACs were modified and are characterized by persistent headache or headache attacks accompanied by cranial autonomic symptoms. The main difference between the various TACs is the duration of attacks. Differentiation is important because different pharmacological strategies are necessary.

Differences in clinical characteristics and frequency of accompanying migraine features in episodic and chronic cluster headache.

INTRODUCTION: Data on clinical differences between episodic (eCH) and chronic cluster headache (cCH) and accompanying migraine features are limited. METHODS: History and clinical features of 209 consecutive cluster headache patients (144 eCH, 65 cCH; male:female ratio 3.4 : 1) were obtained in a tertiary headache centre by face-to-face interviews. Relationship between occurrence of accompanying symptoms, pain intensity, comorbid migraine, and circannual and circadian rhythmicity was analysed. RESULTS: 99.5% of patients reported a minimum of one ipsilateral cranial autonomic symptom (CAS); 80% showed at least three CAS. A seasonal rhythmicity was observed in both eCH and cCH. A comorbid headache disorder occurred in 25%. No significant difference was detected between patients with comorbid migraine and without regarding occurrence of phonophobia, photophobia or nausea during cluster attacks. Patients with comorbid migraine reported allodynia significantly (p = 0.022) more often during cluster attacks than patients without comorbid migraine. CONCLUSION: Occurrence of CAS and attack frequency, as well as periodic patterns of attacks, are relatively uniform in eCH and cCH. Multiple CAS are not related to pain intensity. Allodynia during cluster attacks is a frequent symptom. The unexpectedly high rate of accompanying migrainous features during cluster attacks cannot be explained by comorbid migraine.

Lateralized central facilitation of trigeminal nociception in cluster headache.

OBJECTIVE: To investigate whether central facilitation of trigeminal pain processing is part of the pathophysiology of cluster headache (CH). METHODS: Sixty-six patients with CH (18 episodic CH inside bout, 28 episodic CH outside bout, 20 chronic CH) according to the International Classification of Headache Disorders-II classification, as well as 30 healthy controls, were investigated in a case-control study using simultaneous recordings of the nociceptive blink reflex (nBR) and pain-related evoked potentials (PREP) following nociceptive electrical stimulation on both sides of the forehead (V1). RESULTS: nBR latency ratio (headache side/nonheadache side) was decreased in all CH patients independent from CH subtype compared with healthy controls indicating central facilitation at brainstem level. Area under the curve ratio was increased in patients with episodic CH inside bout only. PREP showed decreased N2 latency ratio in patients with chronic CH indicating central facilitation at supraspinal (thalamic or cortical) level. CONCLUSIONS: Asymmetric facilitation of trigeminal nociceptive processing predominantly on brainstem level was detected in patients with CH. This alteration is most pronounced in the acute pain phase of the disease, but appears to persist in remission periods. Only chronic CH patients show additional changes of PREP prompting to supraspinal changes of pain processing related to the chronic state of disease in regard to neuronal plasticity, which exceeds changes observed in episodic CH.

[Migraine variants and unusual types of migraine in childhood]. / Migränevarianten und ungewöhnliche Manifestationen der Migräne im Kindesalter.

Migraine is a frequent primary headache disorder in children and adolescents. Most of the young sufferers of migraine describe typical migraine symptoms but sometimes rare forms of migraine variants and unusual types of migraine occur in children and adolescents. These childhood periodic syndromes are common precursors of migraine. Phenotypes are alternating hemiplegia of childhood, benign paroxysmal torticollis, benign paroxysmal vertigo of childhood, alternating hemiplegia in childhood, Alice in Wonderland syndrome, cyclic vomiting syndrome, acute confusional migraine and abdominal migraine.

[The value of "migraine surgery". Overview of the pathophysiological concept and current evidence]. / Stellenwert der "Migränechirurgie". Ubersicht über das pathophysiologische Konzept und die aktuelle Datenlage.

Often without sufficient scientific evidence, unconventional methods for migraine treatment are being put forward. Recently a trial using "migraine surgery" has been published. Its design is based on a concept of migraine pathogenesis without any scientific background and includes several severe methodological flaws. In spite of the above, the study is frequently cited in the lay press. The surgical procedure as well as the study are critically discussed.

Gray matter changes related to chronic posttraumatic headache.

BACKGROUND: Although up to 15% of patients with whiplash injury develop chronic headache, the basis and mechanisms of this posttraumatic headache are not well understood. METHODS: Thirty-two patients with posttraumatic headache following whiplash injury were investigated within 14 days after the accident and again after 3 months using magnetic resonance-based voxel-based morphometry. Twelve patients developed chronic headache lasting longer than 3 months and were studied a third time after 1 year. RESULTS: Patients who developed chronic headache revealed decreases in gray matter in the anterior cingulate and dorsolateral prefrontal cortex after 3 months. These changes resolved after 1 year, in parallel to the cessation of headache. The same patients who developed chronic headache showed an increase of gray matter in antinociceptive brainstem centers, thalamus, and cerebellum 1 year after the accident. CONCLUSION: We demonstrate adaptive gray matter changes of pain processing structures in patients with chronic posttraumatic headache in regard to neuronal plasticity, thus providing a biologically plausible basis for this common, disabling problem.

Current management and risk of recurrent stroke in cerebrovascular patients with right-to-left cardiac shunt.

BACKGROUND: Right-to-left cardiac shunt (RLS) is considered a risk factor for stroke, especially in patients aged <55 years. We aimed to investigate the current management and prognosis in consecutive patients with RLS and otherwise cryptogenic cerebrovascular events. METHODS: In total, 1,126 patients with cryptogenic stroke or TIA were included from 17 German neurology departments. During a mean follow-up of 28.4 months, we assessed current antithrombotic medication, percutaneous device closure (PDC) and recurrent cerebrovascular events in 899 patients (79.8%). Stroke recurrence was compared between 548 patients without RLS and 351 patients with RLS under various prevention regimens. RESULTS: RLS was detected in 35.9% of cryptogenic cerebrovascular patients, but could not be evaluated as an independent predictor for recurrent stroke (adjusted HR 1.6, 95% CI: 0.9-2.7). In RLS-positive patients, the Kaplan-Meier estimate for stroke during the first year was 4.1% (95% CI: 1.9-6.3%) and 1.7% (95% CI: 0.9-2.4%) per year thereafter. At the last follow-up before recurrent stroke or end of study, 117 RLS-positive patients (33.3%) had received a PDC, 154 (43.9%) were receiving antiplatelets, 63 (17.9%) received anticoagulation, and 17 (4.8%) received none of the above. No association with recurrent stroke was found for the secondary preventive regime. CONCLUSION: Our multicenter hospital-based cohort study confirmed low recurrent event rates in RLS patients with otherwise cryptogenic stroke or TIA, as well as a great heterogeneity of current management. Despite the lack of scientific evidence, a substantial number of RLS-positive patients underwent PDC for secondary stroke prevention.

The geographic form of retinal dysplasia in dogs is not always a congenital abnormality.

To examine the congenital nature of the geographic form of focal/multifocal retinal dysplasia, we carried out a retrospective analysis of the medical records of dogs produced in a closed colony of service dogs who receive very thorough ophthalmologic examinations early in their life, and later, when they return for training. Medical records were reviewed from all dogs produced by The Seeing Eye, Inc. between October 1991 and September 1998, and which had a diagnosis of geographic retinal dysplasia coded. We identified 23 dogs of five different breeds or interbreed crosses that comprise the breeding and production program (Golden Retrievers, German Shepherds, Labrador Retrievers, Labrador Retriever/Golden Retriever cross and German Shepherd/Labrador Retriever cross) in which the results of at least two complete ophthalmic examinations were documented, the first before 10 weeks of age, and the second when the dog was a young adult. Of the 23 dogs, only one was identified as affected with the geographic form of retinal dysplasia when examined at 5-6 weeks of age. The remaining dogs were normal. Our findings indicate that, in most cases, the geographic form of retinal dysplasia is not present in dogs prior to 10 weeks of age. These findings indicate the need to revise recommendations for early screening of dogs for retinal dysplasia.