Headache
| Headache | |
|---|---|
| Specialty | Neurology  |
In medicine a headache or cephalalgia is a symptom of a number of different conditions of the head.[1] Headache is caused by a disturbance of the pain-sensitive structures in the head. The brain in itself is not sensitive to pain, because it lacks nociceptors. Several areas of the head and neck have the pain-sensitive structures. The pain-sensitive structures are divided in two: within the cranium (blood vessels, meninges, and the cranial nerves) and outside the cranium (the periosteum of the skull, muscles, nerves, arteries and veins, subcutaneous tissues, eyes, ears, sinuses and mucous membranes).
There are a number of different classification systems for headaches. The most well-recognized is that of the International Headache Society. Treatment of a headache depends on the underlying etiology or cause, but commonly involves analgesics.
Classification
The first recorded classification system that resembles the modern ones was published by Thomas Willis, in De Cephalagia in 1672. In 1787 Christian Baur generally divided headaches into idiopathic (primary headaches) and symptomatic (secondary ones), and defined 84 categories.[2]
Today headaches are most thoroughly classified by the International Headache Society's International Classification of Headache Disorders (ICHD), which published the second edition in 2004.[3] This classification is accepted by the WHO.[4]
Other classification systems exist. One of the first published attempts was in 1951.[5] The National Institutes of Health developed a classification system in 1962.[citation needed]
Headaches can also be classified by severity and acuity of onset. Headaches that are both severe and acute are known as thunderclap headaches.[citation needed]
ICHD-2
The International Classification of Headache Disorders (ICHD) is an in-depth hierarchical classification of headaches published by the International Headache Society. It contains explicit (operational) diagnostic criteria for headache disorders. The first version of the classification, ICHD-1, was published in 1988. The current revision, ICHD-2, was published in 2004.[6]
The classification uses numeric codes. The top, one-digit diagnostic level includes 14 headache groups. The first four of these are classified as primary headaches, groups 5-12 as secondary headaches, cranial neuralgia, central and primary facial pain and other headaches for the last two groups.[7]
NIH
The NIH classification consists of brief definitions of a limited number of headaches.[2]
Symptoms and signs
Headache associated with specific symptoms may warrant urgent medical attention, particularly sudden, severe headache or sudden headache associated with a stiff neck; headaches associated with fever, convulsion, or accompanied by confusion or loss of consciousness; headaches following a blow to the head, or associated with pain in the eye or ear; persistent headache in a person with no previous history of headaches; and recurring headache in children.[citation needed]
Pathophysiology
The brain in itself is not sensitive to pain, because it lacks nociceptors. However, several areas of the head and neck do have nociceptors, and can thus sense pain. These include the extracranial arteries, large veins, cranial and spinal nerves, head and neck muscles and the meninges.[8]
Diagnosis
In 2008, the American College of Emergency Physicians updated their guidelines on the evaluation and management of adult patients who have a nontraumatic headache of acute onset.[8]
While, statistically, headaches are most likely to be primary (harmless and self-limiting), some specific secondary headache syndromes may demand specific treatment or may be warning signals of more serious disorders.[citation needed] Differentiating between primary and secondary headaches can be difficult.
As it is often difficult for patients to recall the precise details regarding each headache, it is often useful for the sufferer to fill-out a "headache diary" detailing the characteristics of the headache.
Imaging
When the headache does not clearly fit into one of the recognized primary headache syndromes or when atypical symptoms or signs are present then further investigations are justified.[9] Neuroimaging (noncontrast head CT) is recommended if there are new neurological problems such as decreased level of consciousness, one sided weakness, pupil size difference, etc or if the pain is of sudden onset and severe, or if the person is known HIV positive.[8] People over the age of 50 years may also warrant a CT scan.[8]
Treatment
Acute headaches
Not all headaches require medical attention, and most respond with simple analgesia (painkillers) such as paracetamol/acetaminophen or members of the NSAID class (such as aspirin/acetylsalicylic acid, diclofenac or ibuprofen).[citation needed]
A small 2009 study found that 100% oxygen at 15 l / min was effective at relieving undifferentiated headache pain in the emergency department.
Chronic headaches
In recurrent unexplained headaches keeping a "headache diary" with entries on type of headache, associated symptoms, precipitating and aggravating factors may be helpful. This may reveal specific patterns, such as an association with medication, menstruation or absenteeism or with certain foods. It was reported in March 2007 by two separate teams of researchers that stimulating the brain with implanted electrodes appears to help ease the pain of cluster headaches.[10]
Acupuncture has been found to be beneficial in chronic headaches[11] of both tension type[12] and migraine type.[13] Whether or not there is a difference between true acupuncture and sham acupuncture however is yet to be determined.[13]
Epidemiology
During a given year, 90% of people suffer with headaches. Of the ones who are seen in the ER, about 1% have a serious underlying problem.[14]
References
- ^ "headache" at Dorland's Medical Dictionary
- ^ a b Levine et al., p 60
- ^ "216.25.100.131" (PDF). the Headache Classification Subcommittee of the International Headache Society.
- ^ Olsen et al., p. 9–11
- ^ BROWN MR (1951). "The classification and treatment of headache". Med. Clin. North Am. 35 (5): 1485–93. PMID 14862569.
{{cite journal}}: Unknown parameter|month=ignored (help) - ^ Jes Olesen, Peter J. Goadsby, Nabih M. Ramadan, Peer Tfelt-Hansen, K. Michael A. Welch (2005). The Headaches (3 ed.). Lippincott Williams & Wilkins. ISBN 0781754003.
{{cite book}}: CS1 maint: multiple names: authors list (link) - ^ Morris Levin, Steven M. Baskin, Marcelo E. Bigal (2008). Comprehensive Review of Headache Medicine. Oxford University Press US. ISBN 0195366735.
{{cite book}}: CS1 maint: multiple names: authors list (link) - ^ a b c d Edlow JA, Panagos PD, Godwin SA, Thomas TL, Decker WW (2008). "Clinical policy: critical issues in the evaluation and management of adult patients presenting to the emergency department with acute headache". Ann Emerg Med. 52 (4): 407–36. doi:10.1016/j.annemergmed.2008.07.001. PMID 18809105.
{{cite journal}}: Unknown parameter|month=ignored (help)CS1 maint: multiple names: authors list (link) - ^ Detsky ME, McDonald DR, Baerlocher MO, Tomlinson GA, McCrory DC, Booth CM. Does this patient with headache have a migraine or need neuroimaging? JAMA 2006;296:1274–83
- ^ Brain Stimulation May Ease Headaches. Reuters, March 9, 2007.
- ^ Sun Y, Gan TJ (2008). "Acupuncture for the management of chronic headache: a systematic review". Anesth. Analg. 107 (6): 2038–47. doi:10.1213/ane.0b013e318187c76a. PMID 19020156.
{{cite journal}}: Unknown parameter|month=ignored (help) - ^ Linde, K.; Allais, G.; Brinkhaus, B.; Manheimer, E.; Vickers, A.; White, AR.; Linde, Klaus (2009). "Acupuncture for tension-type headache". Cochrane Database Syst Rev (1): CD007587. doi:10.1002/14651858.CD007587. PMID 19160338.
{{cite journal}}: Cite has empty unknown parameter:|month=(help) - ^ a b Linde, K.; Allais, G.; Brinkhaus, B.; Manheimer, E.; Vickers, A.; White, AR.; Linde, Klaus (2009). "Acupuncture for migraine prophylaxis". Cochrane Database Syst Rev (1): CD001218. doi:10.1002/14651858.CD001218.pub2. PMID 19160193.
{{cite journal}}: Cite has empty unknown parameter:|month=(help) - ^ Amal Mattu; Deepi Goyal; Barrett, Jeffrey W.; Joshua Broder; DeAngelis, Michael; Peter Deblieux; Gus M. Garmel; Richard Harrigan; David Karras; Anita L'Italien; David Manthey (2007). Emergency medicine: avoiding the pitfalls and improving the outcomes. Malden, Mass: Blackwell Pub./BMJ Books. p. 39. ISBN 1-4051-4166-2.
{{cite book}}: CS1 maint: multiple names: authors list (link)