Chronic daily headache in the adults: differential diagnosis between symptomatic Chiari I malformation and spontaneous intracranial hypotension.

This article briefly reviews the spectrum of headaches associated with Chiari type I malformation (CMI) and specifically analyzes the current data on the possibility of this malformation as an etiology for some cases of chronic daily headache (CDH). CMI is definitely associated with cough headache and not with primary episodic headaches, with the rare exception of basilar migraine-like cases. With regard to CDH, there is no clear evidence supporting an association with CMI. A magnetic resonance imaging (MRI) study would be justified only in patients showing either a Valsalva-aggravating component or cervicogenic features. Hydrocephalus and low-intracranial pressure syndrome should be ruled out in patients showing tonsillar herniation in an MRI study and consulting due to daily headache.

Management of chronic cluster headache.

OPINION STATEMENT: Primary cluster headache (CH) is an excruciatingly severe pain condition. Several pharmacologic agents are available to treat chronic CH, but few double-blind, randomized clinical trials have been conducted on these agents in recent years, and the quality of the evidence supporting their use is often low, particularly for preventive agents. We recommend sumatriptan or oxygen to abort ongoing headaches; the evidence available to support their use is good (Class I). Ergotamine also appears to be an effective abortive agent, on the basis of experience rather than trials. We consider verapamil and lithium to be first-line preventives for chronic CH, although the trial evidence is at best Class II. Steroids are clearly the most effective and quick-acting preventive agents for chronic CH, but long-term steroid use carries a risk of several severe adverse effects. We therefore recommend steroids only if verapamil, lithium, and other preventive agents are ineffective. In rare cases, patients experience multiple daily cluster headaches for years and are also refractory to all medications. These patients almost always develop severe adverse effects from chronic steroid use. Such patients should be considered for neurostimulation. Occipital nerve stimulation is the newest and least invasive neurostimulation technique and should be tried first; the evidence supporting its use is encouraging. Hypothalamic stimulation is more invasive and can be performed only in specialist neurosurgical centers. Published experience suggests that about 60% of patients with chronic CH obtain long-term benefit with hypothalamic stimulation.

Frovatriptan versus zolmitriptan for the acute treatment of migraine: a double-blind, randomized, multicenter, Italian study.

The objective of this study is to assess patients' satisfaction with migraine treatment with frovatriptan (F) or zolmitriptan (Z), by preference questionnaire. 133 subjects with a history of migraine with or without aura (IHS criteria) were randomized to F 2.5 mg or Z 2.5 mg. The study had a multicenter, randomized, double-blind, cross-over design, with each of the two treatment periods lasting no more than 3 months. At the end of the study, patients were asked to assign preference to one of the treatments (primary endpoint). The number of pain-free (PF) and pain-relief (PR) episodes at 2 h, and number of recurrent and sustained pain-free (SPF) episodes within 48 h were the secondary study endpoints. Seventy-seven percent of patients expressed a preference. Average score of preference was 2.9 +/- 1.3 (F) versus 3.0 +/- 1.3 (Z; p = NS). Rate of PF episodes at 2 h was 26% with F and 31% with Z (p = NS). PR episodes at 2 h were 57% for F and 58% for Z (p = NS). Rate of recurrence was 21 (F) and 24% (Z; p = NS). Time to recurrence within 48 h was better for F especially between 4 and 16 h (p < 0.05). SPF episodes were 18 (F) versus 22% (Z; p = NS). Drug-related adverse events were significantly (p < 0.05) less under F (3 vs. 10). In conclusion, our study suggests that F has a similar efficacy of Z, with some advantage as regards tolerability and recurrence.

Drug-resistant primary headache patients undergoing surgical therapies: how should we assess outcomes?

The introduction of neurostimulation procedures for chronic drug-resistant primary headaches has offered new hope to patients, but has also introduced new problems. The methods to be used in assessing clinical outcomes and monitoring treatment efficacy need careful attention. The International Headache Society guidelines recommend that treatment efficacy should be monitored by getting patients to report the number of attacks per day, in a headache diary. The headache diary is a fundamental instrument for objectively assessing subjective pain in terms of headache frequency, intensity and duration and analgesic consumption. The huge discrepancy sometimes reported between patient satisfaction and headache improvement suggests that patient satisfaction should not be a primary efficacy endpoint, and more importantly should not be put forward as an argument in establishing the efficacy of highly experimental neurostimulation procedures.

Deep brain stimulation in trigeminal autonomic cephalalgias.

Cluster headache (CH), paroxysmal hemicrania (PH), and short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT syndrome) are primary headaches grouped together as trigeminal autonomic cephalalgias (TACs). All are characterized by short-lived unilateral head pain attacks associated with oculofacial autonomic phenomena. Neuroimaging studies have demonstrated that the posterior hypothalamus is activated during attacks, implicating hypothalamic hyperactivity in TAC pathophysiology and suggesting stimulation of the ipsilateral posterior hypothalamus as a means of preventing intractable CH. After almost 10 years of experience, hypothalamic stimulation has proved successful in preventing pain attacks in approximately 60% of the 58 documented chronic drug-resistant CH patients implanted at various centers. Positive results have also been reported in drug-resistant SUNCT and PH. Microrecording studies on hypothalamic neurons are increasingly being performed and promise to make it possible to more precisely identify the target site. The implantation procedure has generally proved safe, although it carries a small risk of brain hemorrhage. Long-term stimulation is proving to be safe: studies on patients under continuous hypothalamic stimulation have identified nonsymptomatic impairment of orthostatic adaptation as the only noteworthy change. Studies on pain threshold in chronically stimulated patients show increased threshold for cold pain in the distribution of the first trigeminal branch ipsilateral to stimulation. When the stimulator is switched off, changes in sensory and pain thresholds do not occur immediately, indicating that long-term hypothalamic stimulation is necessary to produce sensory and nociceptive changes, as also indicated by clinical experience that CH attacks are brought under control only after weeks of stimulation. Infection, transient loss of consciousness, and micturition syncope have been reported, but treatment interruption usually is not required.

Spontaneous intracranial hypotension syndrome: a novel speculative physiopathological hypothesis and a novel patch method in a series of 28 consecutive patients.

OBJECT: Spontaneous intracranial hypotension (SIH) is a potentially serious pathological syndrome consisting of specific symptoms and neuroradiological signs that can sometimes be used to assess the efficacy of the treatment. In this paper the authors report a series of 28 patients with this syndrome who were all treated with an epidural blood patch at the authors' institution. The authors propose a novel physiopathological theory of SIH based on some anatomical considerations about the spinal venous drainage system. METHODS: Between January 1993 and January 2007, the authors treated 28 patients in whom SIH had been diagnosed. Twenty-seven of the 28 patients presented with the typical findings of SIH on brain MR imaging (dural enhancement and thickening subdural collections, caudal displacement of cerebellar tonsils, and reduction in height of suprachiasmatic cisterns). The sites of the patients' neuroradiologically suspected CSF leakage were different, but the blood patch procedure was performed at the lumbar level in all patients. The patients were then assessed at 3-month and 1- and 3-year follow-up visits. At the last visit (although only available for 11 patients) 83.3% of patients were completely free from clinical symptoms and 8.3% complained of sporadic orthostatic headache. RESULTS: The authors think that in the so-called SIH syndrome, the dural leak, even in those cases in which it can be clearly identified on neuroradiological examinations, is not the cause of the disease but the effect of the epidural hypotension maintained by the inferior cava vein outflow to the heart. The goal of their blood patch procedure (a sort of epidural block obtained using autologous blood and fibrin glue at the L1-2 level) is not to seal CSF leaks, but instead to help in reversing the CSF-blood gradient within the epidural space along the entire cord. CONCLUSIONS: The authors' procedure seems to lead to good and long-lasting clinical results.

Hypothalamic deep-brain stimulation modulates thermal sensitivity and pain thresholds in cluster headache.

Deep-brain stimulation (DBS) of the posterior hypothalamus has been shown to be clinically effective for drug-resistant chronic cluster headache, but the underlying mechanism is still not understood. The hypothalamus as an important centre of homeostasis is connected among others to the trigeminal system via the trigeminohypothalamic tract. We aimed to elucidate whether hypothalamic stimulation affects thermal sensation and pain perception only in the clinically affected region (the first trigeminal branch) or in other regions as well. Thus, we examined three groups: chronic cluster headache patients with unilateral DBS of the posterior hypothalamus (n = 11), chronic cluster headache patients without DBS (n = 15) and healthy controls (n = 29). Perception and pain thresholds for hot and cold stimuli were determined bilaterally in all subjects supraorbitally, at the forearm, and in the lower leg. In DBS patients, thresholds were determined with the stimulator activated and inactivated. Cold pain thresholds at the first trigeminal branch were increased on the stimulated side in the DBS group compared to healthy subjects (p = .015). The DBS group also had higher cold detection thresholds compared to non-implanted cluster headache patients (p < .05). Short-term interruption of stimulation did not induce any changes in DBS patients. Clinically relevant differences were found neither between non-stimulated cluster headache patients and healthy controls nor between the affected and the non-affected sides in the chronic cluster headache patients without DBS. These results support the notion that neurostimulation of the posterior hypothalamus is specific for cluster headache and only affects certain aspects of pain sensation.

Vagus nerve stimulation in drug-resistant daily chronic migraine with depression: preliminary data.

Drug refractory chronic daily headache (CDH) is a highly disabling condition. CDH is usually regarded as the negative evolution of chronic migraine (CM) and is characterized by high prevalence of psychiatric disorders, especially mood disorders. Vagal nerve stimulation (VNS) is an established treatment option for selected patients with medically refractory epilepsy and depression. Neurobiological similarities suggest that VNS could be useful in the treatment of drug-refractory CM associated with depression. The aim of the study was to evaluate the efficacy of VNS in patients suffering from drug-refractory CM and depressive disorder. We selected four female patients, mean age 53 (range 43-65 years), suffering from daily headache and drug-refractory CM. Neurological examination and neuroradiological investigations were unremarkable. Exclusion criteria were psychosis, heart and lung diseases. The preliminary results in our small case series support a beneficial effect of chronic VNS on both drug-refractory CM and depression, and suggest this novel treatment as a valid alternative for this otherwise intractable and highly disabling condition.

Cluster headache: pharmacological treatment and neurostimulation.

Cluster headache is a primary headache syndrome that is characterized by excruciatingly severe, strictly unilateral attacks of orbital, supraorbital or temporal pain, which last 15-180 min and are accompanied by ipsilateral autonomic manifestations (e.g. lacrimation and rhinorrhea). The attacks typically occur with circadian rhythmicity, being experienced at fixed hours of the day or night. In episodic cluster headache, attacks usually occur daily in 6-12-week bouts (cluster periods) followed by remission periods. In chronic cluster headache there is no notable remission. Cluster headache attacks reach full intensity very quickly and abortive agents need to be administered without delay. The pathophysiology of cluster headache is imperfectly understood and treatment has so far been mainly empirical. However, neuroimaging studies have prompted the successful use of hypothalamic stimulation to treat the condition. More recently, the less invasive technique of occipital nerve stimulation has shown promise in drug-refractory chronic cluster headache. This Review discusses both acute and preventive treatments for cluster headache and includes suggestions of how to use the available medications. The rationale, study results and selection criteria for neurostimulation procedures are also summarized, as are the disadvantages of these procedures.

Long-term experience of neuromodulation in TACs.

Improvement in the biomedical and biotechnological research fields have allowed refinement of the neuromodulation approach in the treatment of a subgroup of medical disorders otherwise refractory to pharmacological treatment, such as chronic primary headaches. Chronic pain conditions imply central sensitisations and functional reorganisation that cannot be quickly or easily reversed. It appears evident that conventional treatment can sometimes be unsuccessful or only partially successful, and that relapse is common. Cluster headache (CH) is the most frequent trigeminal autonomic cephalalgia (TAC) and the most representative of this spectrum of disorders characterised by the association of headache and loco-regional signs and symptoms of facial parasympathetic activation. The striking features of circadian rhythmicity of attacks and circannual periodicity of cluster period, together with the neuroendocrine abnormalities, are suggestive of a neurochronobiological disorder with a central-diencephalic pathogenetic involvement, confirmed by direct evidence in functional neuroimaging studies of ipsilateral posterior hypothalamic activation during cluster attack. In 2000 these findings prompted a functional neurosurgery approach, with the first case of deep brain hypothalamic stimulation (DBS) in a severely disabled chronic CH patient. Since then, 18 implants in our centre and many others in different countries have been performed. Although the outcomes are encouraging, the invasive nature of the technique and the occurrence of rare but major adverse events have suggested a safer peripheral approach with occipital nerve stimulation (ONS).

Therapeutic neurostimulation in chronic headaches: problems of patient selection.

Chronic daily headache that does not respond or no longer responds to prophylaxis is commonly encountered at specialist headache centres. Animal and brain imaging studies indicate that peripheral neurostimulation affects brain areas involved in pain modulation, providing a rationale for its use in these conditions. We examine problems related to the selection of chronic daily headache patients for peripheral neurostimulation. These conditions are often associated with analgesic (including opioid) overuse, and psychiatric or other comorbidities, and the terms used to describe them (chronic migraine, transformed migraine, chronic daily headache and chronic tension-type headache) are insufficiently informative about these patients when proposed for neurostimulation. Longitudinal studies indicate that pre-existing subclinical depressive and anxious states play a key role in chronicisation and that the probability of responding to treatment is inversely related to headache frequency. These considerations suggest the need for extensive characterisation of patients proposed for neurostimulation. We propose that patients being considered for neurostimulation should be followed for at least a year, and that their headache over this time should consistently be frequent (all or most days) and drug refractory. We also propose that only completely drug-resistant (as opposed to partially drug-resistant) patients be considered for neurostimulation unless there are other indications.

Application of revised criteria for chronic migraine and medication overuse headache in a tertiary Headache Centre.

Various diagnostic criteria have been proposed for chronic daily headaches. We tested the recently proposed revised criteria of the International Headache Society in a sample of patients with chronic daily headaches, most of whom were overusing acute medications, to assess their applicability in clinical practice compared to alternative classification systems.

Headache attributed to spontaneous intracranial hypotension.

UNLABELLED: Recent evidence suggests that spontaneous intracranial hypotension (SIH) is not as rare as previously thought. Orthostatic headache is the prototypical manifestation of SIH, but various headache syndromes have also been reported such as migraine-like headache, tension-type headache and non-specific headaches among the others. The International Headache Society (IHS) has recently proposed diagnostic criteria for headache attributed to SIH. Seventy patients consecutively seen at our institution between 1993 and 2005 and diagnosed with SIH were included in the study. SIH diagnosis was confirmed in all patients by brain-enhanced MRI: 23 were males (33%), 47 females (77%) and mean age was 45 years (range 18-69). FOLLOW-UP: median value 35 months (range: 8 months-14 years). Time between symptom onset and diagnosis was 4 months (median) (range 15 days-45 months). The IHS (2004) criteria for "Headache attributed to SIH" were applied. Typical brain imaging findings confirmed the diagnosis of SIH in all patients: criteria B and C were fulfilled in all patients. Criterion A of the IHS classification was not fulfilled in 34 (49%) patients. Sixty-two (89%) patients did not fulfil criterion D of the IHS classification; 28 (40%) did not fulfil both criterion A and D. So far, only 2 (3%) fulfilled all IHS criteria for headache attributed to SIH. The IHS criteria for headache attributed to SIH could not classify the headache in most of our SIH patients. A revision of the IHS criteria for headache attributed to SIH is necessary.

Spontaneous intracranial hypotension with deep brain swelling.

Spontaneous intracranial hypotension (SIH) is caused by leakage of CSF, and characterized on MRI by brain sagging, dilatation of veins and dural sinuses, subdural fluid collections and post-contrast enhancement of the thickened dura. A few cases may present a very severe brain sagging through the tentorial notch and swelling of the diencephalic-mesencephalic structures, with absent or scarce subdural collections and post-contrast enhancement. These patients may have surprisingly few neurological signs or may become drowsy and even lapse into coma due to central herniation. We retrospectively examined the diffusion studies obtained in five patients with these MRI findings, in seven patients with SIH without brain swellings and in ten controls. Mean diffusivity was increased in SIH patients with brain swelling in areas draining into the deep venous system, collected by the vein of Galen (vG) and straight sinus (SS). In the hypothesis that central herniation might be responsible for venous stagnation because of impaired flow of the vG into the SS, the vG/SS angle was measured. The angle formed by the vG entering the SS was not altered in patients without brain swelling (group E, 67.8 degrees +/- 10.3 degrees, mean +/- SD, range 49-80 degrees) when compared to controls (group C, 73.3 degrees +/- 12.3 degrees, mean +/- SD, range 56-95 degrees). It was, however, grossly decreased in patients with brain swelling (group D, 40.7 degrees +/- 12.8 degrees, mean +/- SD, range 22-61 degrees), P < 0.001 for comparison with groups E and C. As suggested by previous studies, downward stretching of the vG and narrowing of the vG/SS angle may cause a functional stenosis at the vG-SS junction. We suggest that in the application of the Monro-Kellie doctrine to SIH, the brain volume should not be considered as always invariable.

Coexistence of TACS and trigeminal neuralgia: pathophysiological conjectures.

BACKGROUND: Trigeminal autonomic cephalgias (TACs) and trigeminal neuralgia are short-lasting unilateral primary headaches whose study is providing insights into craniofacial pain mechanisms. We report on 2 patients in whom trigeminal neuralgia coexists with the TACs paroxysmal hemicrania and SUNCT. CONCLUSION: Coexistence of trigeminal neuralgia with various TAC forms suggests a pathophysiological relationship between these short-lasting unilateral headaches.

Dural sinus thrombosis in spontaneous intracranial hypotension: Hypotheses on possible mechanisms.

Dural sinus thrombosis (DST) is rarely associated with spontaneous intracranial hypotension (SIH). Engorgement of the venous system, caused by the CSF loss that occurs in SIH, is considered to favour the thrombosis, although signs of both SIH and DST are usually seen simultaneously at the first diagnostic MRI. We observed two patients with SIH and DST. Changes in pattern of headaches and MRI findings demonstrated that DST followed SIH. In SIH, the velocity of the blood flow in the dural sinuses may be reduced because of dilatation of the venous system which compensates the CSF loss. Other possible mechanisms seem unlikely on the grounds of both clinical presentation and MRI studies.