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Hemicrania continua. Unquestionably a trigeminal autonomic cephalalgia
1Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
Headache
|April 12, 2013
Summary
Hemicrania continua (HC) is reclassified as a trigeminal autonomic cephalalgia, not a miscellaneous headache. Evidence shows shared clinical features, indomethacin response, and hypothalamic activation with other TACs.
Area of Science:
- Neurology
- Headache Medicine
Background:
- Hemicrania continua (HC) is currently classified under 'other primary headaches' in the International Classification of Headache Disorders.
- Emerging evidence suggests HC shares characteristics with trigeminal autonomic cephalalgias (TACs).
Purpose of the Study:
- To evaluate the evidence supporting the reclassification of Hemicrania continua (HC) as a trigeminal autonomic cephalalgia (TAC).
- To consolidate clinical, therapeutic, and neuroimaging data to support HC's placement within the TAC spectrum.
Main Methods:
- Review of clinical presentations of HC and other TACs (cluster headache, paroxysmal hemicrania, SUNHA).
- Analysis of treatment responses, particularly to indomethacin.
- Examination of neuroimaging findings, focusing on hypothalamic activation patterns.
Main Results:
- HC exhibits a shared clinical profile with TACs: paroxysmal, unilateral, side-locked headaches with ipsilateral autonomic symptoms.
- Indomethacin demonstrates a unique and potent efficacy in HC, mirroring its effect in paroxysmal hemicrania.
- Neuroimaging reveals posterior hypothalamic activation in HC, consistent with other TACs.
Conclusions:
- Hemicrania continua (HC) demonstrates sufficient shared features with cluster headache, paroxysmal hemicrania, and SUNHA to be classified as a trigeminal autonomic cephalalgia.
- The current classification of HC as a miscellaneous primary headache is outdated and does not reflect its underlying pathophysiology.
- HC should be integrated into the spectrum of trigeminal autonomic cephalalgias based on clinical, therapeutic, and neuroimaging evidence.
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