Electroencephalography in the evaluation of headache patients: a review

The intention of this paper was to review the literature on the use of EEG in headache evaluation and recommend clinical applications of this technique. The consensus of published findings was that EEG can differentiate migraineurs from controls but that it is not justified for routine diagnosis of headache etiology. We conclude that neuroimaging is a superior technique for detecting underlying structural lesions.     

Methylergonovine maleate as a cluster headache prophylactic: a study and review

Methylergonovine maleate (Methergine), an ergot derivative with vasoconstrictive properties, has been cited as an effective treatment for vascular headaches. Few studies are available to support its use in headache management. An uncontrolled pilot study of 20 episodic cluster headache patients confirmed its effectiveness and tolerability as an adjunct cluster headache prophylactic. Decreased headache frequency was reported by 19 of 20 patients (95%), and 15 of 20 patients (75%) reported decreased intensity of headaches within 1 week of initiating therapy. A review of methylergonovine's pharmacokinetic, molecular, and tolerability profile clarifies its mechanisms and clinical role in headache management.     

Behaviour during a cluster headache

Because cluster headache is short-lasting and tends to occur during the early morning hours, physicians rarely witness an attack. Accurate diagnosis is important because effective treatments are available. The diagnosis is made from the history of temporal pattern, reddening and tearing of the affected eye, and ipsilateral nasal congestion. An additional diagnostic aid is to invite patients to demonstrate how they respond to attacks. The pain, one of the worst known, causes extreme restlessness. 50 patients showed how they walk around, sit (or kneel) and rock, and clutch the affected side of the head. Diagnostic value apart, the patient will often be relieved to learn that bizarre behavioural responses are not a mark of insanity.     

Spontaneous intracranial hypotension: headache with a reversible Arnold-Chiari malformation

Spontaneous intracranial hypotension is characterized by severe postural headache in the setting of low CSF pressure, usually attributed to a cryptic CSF leak. We report a patient whose prolonged refractory headache was characterized by the clinical symptoms of occipital neuralgia, but was also associated with the radiographic appearance of an Arnold-Chiari malformation, type I and low CSF pressure. After extensive diagnostic evaluation, CT cisternomyelography ultimately demonstrated a CSF leak at the C2 vertebral level. Symptomatic relief was sustained only with long-term theophylline administration. The apparent Arnold-Chiari malformation resolved with treatment of the low CSF pressure.     

Prevalence of migraine headache in Canada: a population-based survey

BACKGROUND: The aim of the present study was to estimate the prevalence of migraine headache among Canadian adults (aged > or = 18 years) and analyse variation by age, gender, household income and province of residence. METHODS: A population-based survey was undertaken using telephone interviews with 2922 adults who were randomly selected from households across Canada by stratified regional sampling. The questionnaire asked about frequency and characteristics of headaches experienced and other symptoms. The diagnostic criteria of the International Headache Society were used to classify people as migraineurs (with or without aura), headachers or non-headachers. RESULTS: Of 8921 random calls to households, 4235 were eligible and 2922 interviews were successfully completed (response rate 66%). The prevalence of migraineurs, headachers and non-headachers among males was 7.8%, 76.1%, 16.1% and among females was 24.9%, 65.6%, 9.4%. For females prevalence appears to increase with age, peaking at 40-44 years and declining thereafter. Sex-specific prevalence for males and females, controlling for age, was significantly lower in the province of Quebec compared to other provinces. We found no association between migraine prevalence and household income. Of 500 people classified by IHS criteria as migraineurs only 232 (46%) reported any migraine diagnosis by a physician. CONCLUSION: We estimate that 2.6 million adult females and 0.8 million adult males in Canada are migraineurs, but only half are likely to have been diagnosed by a physician. Contrary to a recent US survey, people from lower income households in Canada are not at greater risk of migraine. The lower prevalence of migraine in Quebec was unexpected and remains unexplained, but it may be influenced by language/translation problems.     

Posttraumatic headache: determining chronicity

In the headache literature, there exists a great deal of discrepancy regarding when posttraumatic headache (PTH) may be classified as chronic. Although chronic pain is usually described as pain persisting for longer than six months, many view chronic posttraumatic headache as persisting for more than two months, including the International Headache Society criteria. Observations made by Brenner and Friedman in 1944 have been repeatedly cited for this determination. Surprisingly, a review of this original source revealed that the term "chronic" was never used when discussing posttraumatic headache over two months duration. The authors, in fact, suggested two months as an "arbitrary" dividing line. Recent studies suggest that many patients with PTH continue to improve or change over the first six months but start to plateau after that time. We feel six months serves as a better time indicator for defining chronicity in cases of posttraumatic headache. This would be more consistent with the current literature concerning chronic pain and the international Headache Society criteria for chronic tension headache.     

Idiopathic intracranial hypertension without papilledema: a case-control study in a headache center

OBJECTIVE: To compare the clinical features of patients with chronic daily headache (CDH) with idiopathic intracranial hypertension without papilledema (IIHWOP) to those with normal CSF pressure. METHODS: A case-control study was conducted at a tertiary headache center. Cases consisted of 25 consecutive patients (24 women, 1 man, 38 +/- 6 years) with IIHWOP diagnosed between June 1989 and June 1996. IIHWOP was diagnosed if pressure was 200 mm CSF on two occasions and there was no papilledema. Control subjects consisted of patients with refractory CDH who had normal CSF pressure on lumbar puncture performed between June 1992 and June 1996 (n = 60, 50 women, 10 men, 36 +/- 11 years). A structured telephone follow-up was done from July 1996 to March 1997. Comparisons made between the two groups included demographics and headache profiles, both at the initial evaluation and at follow-up. RESULTS: The initial headache characteristics did not differ between the two groups: most had transformed migraine with analgesic overuse. Significant predictors of IIHWOP included pulsatile tinnitus (odds ratio [OR] = 13.0) and obesity (OR = 4.4). Visual symptoms did not differ significantly. The prognosis of the two groups of patients was similar. CONCLUSIONS: Pulsatile tinnitus and obesity suggest possible IIHWOP in patients with CDH. Treatment of patients with increased intracranial pressure was not satisfactory.     

Cluster headache: Horton's cephalalgia revisited

BACKGROUND: Cluster headache (CH), though not fully characterized until this century, is a relatively common primary headache disorder. METHODS: We reviewed pertinent literature on CH and related cephalalgias. RESULTS: We found that CH typically occurs in middle-aged men and has a characteristic cyclic temporal pattern. During the cluster cycle, CH paroxysms last from 15 to 180 minutes and are manifested by excruciating periorbital or upper facial pain. Associated autonomic symptoms such as lacrimation, rhinorrhea, conjunctival injection, and Horner's syndrome are common in CH. Its pathophysiology is not entirely understood, though it may include a complex cascade of autonomic, immunologic, and vascular phenomena. CONCLUSIONS: Although its pathophysiology is still not completely understood, we present the most recent evidence regarding the underlying anatomic and biochemical basis for CH. We also present an update on the modern management of CH, including the appropriate use of standard and novel abortive and prophylactic agents, as well as more invasive treatment.     

Myocarditis: a review

BACKGROUND AND OBJECTIVES: Although pediatric sedation (PS) is widely used in emergency departments (ED), the practice of PS in general community hospital (GH) ED has not been described. We surveyed PS practice patterns in pediatric hospitals (CH) and GH and compared frequency and usage between the two groups. METHODS: All CH (n = 115) and 400 randomly selected GH were surveyed. Alcohol and drug detoxification, psychiatric, chronic care, rehabilitation, and specialty facilities were excluded. Data were collected on hospital type (pediatric or community), location (urban, suburban, rural), annual visits, academic affiliation (presence of an emergency medicine residency or pediatric emergency medicine fellowship in the hospital), and sedation agents used. RESULTS: Of 515 hospitals surveyed, 238 responded [84/115 CH (73%), 154/400 GH (39%)] yielding an overall response rate of 46%. Of the responding CH the majority were urban [57 (68%) were urban, 15 (18%) suburban, and 12 (14%) rural]. GH were more evenly distributed by location [44/153 (29%) were urban, 49/153 (32%) suburban, and 60/153 (39%) rural]. Eight (5%) GH had emergency medicine residencies, while 39 (46%) CH had pediatric emergency medicine fellowships. The mean annual pediatric volume was 38,000 for CH and 6500 for GH. For the four specified clinical scenarios, representing the most common ED procedures using sedation (laceration repair, fracture reduction, radiologic imaging), GH performed significantly fewer sedations than CH when matched for pediatric volume. PS was less frequently used among rural GH compared to suburban (P < 0.01) and urban GH (P < 0.01). Midazolam was listed as the most frequently used drug in all three geographic locations for both CH and GH. CH listed fentanyl as a second agent, while GH preferred meperidine. Fentanyl and ketamine were listed as preferred agents only in CH. For cranial computerized tomography, chloral hydrate was listed as the drug of choice by both CH and GH. Both CH and GH listed "relief of pain and anxiety" as the first and "agitation control" as the second most common reason for using sedation. CH and GH listed "the risks outweigh the benefits" as the primary reason and "ED too busy/takes too much time" as the secondary reason for not using sedation. CONCLUSIONS: GH performed fewer sedations than did CH when matched for pediatric volume in all geographic locations and for the most common ED procedures using sedation. Since 1989, sedation patterns have shifted in CH to include the short-acting agents, while GH (with the exception of midazolam) continue to prefer the long-acting agents. Midazolam is now the most frequently used sedation agent for ED procedures in both CH and GH.     

Hysteroscopy: a review

3 chemicals were selected for mutagenicity testing from a priority list, based on production volume and available mutagenicity data. Propargyl alcohol (PA), 2-nitroaniline (2NA), and 5-methyl-1H-benzo-triazole (MBT) were selected for testing using the approach recommended in the Health Protection Branch Genotoxicity Guidelines. The battery of tests included the Salmonella/mammalian microsome mutation assay, the in vitro chromosomal aberration assay, and the bone-marrow micronucleus assay. The results indicate that 2 of the 3 chemicals, PA and 2NA, were clastogenic in vitro. Both PA and 2NA induced chromosomal aberrations in CHO cells in vitro with and without metabolic activation, while none induced reverse mutations detectable with the Salmonella/mammalian microsome assay. Because PA and 2NA were found to be in vitro clastogens, they also were tested in the mouse bone-marrow micronucleus assay. 2NA induced a small increase in micronuclei in males but not females. PA did not induce an increase in micronuclei.     

Teleradiology: a review

The Biographical Personality Interview (BPI) was applied to 179 subjects (158 psychiatric patients and 21 probands from the general population); 100 patients and 20 healthy controls served as a validation sample; the others had been interviewed during the training period or did not meet the inclusion criteria for the validation of the BPI. The acceptance of the interview was high, the inter-rater reliability of the ratings of premorbid personality structures ("types") varied between 0.81 and 0.88 per type. Concurrent validity of the typological constructs as assessed by means of the BPI was inferred from the intercorrelations of type scores and correlations of these scores with questionnaire data and proved to be adequate. Clinical validity of the assessment was indicated by statistically significant differences between diagnostic groups. Problems and further developments of the instrument and its application are discussed.     

Moxonidine: a review

Moxonidine is an imidazoline compound which acts on I1 imidazoline 'receptors' in the central nervous system to reduce blood pressure. This novel mechanism of action is claimed to lead to fewer adverse effects than the older centrally-acting agents such as clonidine. In this review we examine the drug's pharmacology, clinical pharmacokinetics, efficacy as an antihypertensive agent including comparative studies with pre-existing drugs, and adverse effect profile. With a growing number of effective antihypertensive agents already available to the clinician, it is not yet clear whether moxonidine represents a significant advance in hypertension management.     

Noma: a review

Cancrum oris or noma is a condition not well known in western Europe and North America. It is, however, a relatively common cause of mortality and disability in children of undeveloped areas of Africa, Asia, and South America. This paper describes the experience at Galmi Hospital, in the sub-Saharan region of South Africa in the Niger Republic, with 50 operative patients out of a group of 300 who were referred. An extensive review of the literature is presented describing the epidemiological impact of the disease, the characteristics of the lesions, the pathogenesis, symptoms, sequelae, differential diagnosis, and preoperative preparation. Additionally, we review approaches to anesthesia, methods of reconstruction, and the most common causes of complications and mortality. Numerous photographs illustrating the devastating consequences of this problem are presented.     

Epidemiology of tension-type headache in Santiago, Chile: a prevalence study

OBJECTIVE: To describe the importance of tension-type headache (TTH) in Santiago, Chile, by analyzing its prevalence, clinical features, and impact by age, gender, and socioeconomic status, using widely accepted international diagnostic criteria. METHODS: In 1993, a representative sample of 1540 adults (older than 14) of the province of Santiago were interviewed using a standard questionnaire. A total of 1385 (89.9% response rate) subjects responded to the survey. Initially, a designated member of each household responded to the questionnaire. Subsequently, each household member with headache was asked to respond to questions about the severity, frequency, location, duration, associated symptoms, and impact in work and social activities of their most frequent headaches. TTH diagnoses were determined in accordance with the International Headache Society criteria of 1988. RESULTS: Total prevalence was found to be 26.9% (95% CI: 24.6-29.3%); 35.2% in females (95% CI: 31.7-38.8%) and 18.1% in males (95% CI: 15.2-21.3%). The prevalence of episodic TTH was 24.3% (95% CI: 22.1-26.7%) and of chronic TTH 2.6% (95% CI: 1.8-3.6%). Overall, and by subtype, prevalence was significantly higher in females (ratio 1:9). There was no significant variation in prevalence by socioeconomic or age group except in chronic TTH, in which there was an increase with age. CONCLUSIONS: TTH is a prevalent condition in a sample of adults of Santiago, similar to that reported in previous studies using similar methodologies. Overall, TTH represents 72.3% of all recurrent headaches.