How are cluster headaches diagnosed?
At face value, it would seem that the symptoms of a cluster headache should make it fairly easy to diagnose. However, diagnosis can be difficult due to other types of headaches that mimic the symptoms of a cluster headache.
To help physicians differentiate a cluster headache from other headaches, The International Headache Society (IHS) has developed The International Classification of Headache Disorders (ICHD-3) diagnostic criteria for cluster headache. 1
Their guidelines are as follows:
A. At least five attacks fulfilling criteria B–E
B. Severe or very severe one-sided pain in the eye socket, above the eye and/or temples of head lasting 15–180 minutes (when untreated)
C. Either or both of the following:
- at least one of the following symptoms on same side as the headache:
- Watering or tearing eye
- A runny or blocked nostril
- Swollen or drooping eyelid
- Constriction of the pupil
- Flushing and facial sweating
- a sense of restlessness or agitation
D. Attacks have a frequency between one every other day and eight per day for more than half of the time when the disorder is active
E. Not attributed to another disorder
What type of cluster headache do I have?
There are two types of cluster headache, classified according to the duration of the cluster bout:
1. Episodic Cluster Headache: Occurs in periods lasting seven days to one year, separated by pain-free periods lasting or month or more.
2. Chronic Cluster Headache: Attacks occur for one year or longer without remission or periods lasting less than 3 months.
- Headache Classification Subcommittee of the International Headache Society. The International Classification of Headache Disorders: 3rd ed. Cephalalgia 2013; 33(9) 629–808
- Rozen, TD. Cluster headache in the United States of America: demographics, clinical characteristics, triggers, suicidality, and personal burden. 2012 Jan;52(1):99-113.