Cluster headache

Question 1

What is a cluster headache?

Answer 1

• Cluster headache is considered one of the most painful conditions known to humanity.
• The clinical picture consists of unilateral headache attacks lasting 15 to 180 minutes, associated with autonomic symptoms secondary to parasympathetic hyperactivity and sympathetic hypo-activity.
• Some patients will develop chronic cluster headache and experience daily attacks without periods of remission.
• Pain is often localised to the unilateral orbital, supra-orbital, and/or temporal areas and can occur from once every other day to 8 times per day.
• During an attack the pain is strictly unilateral, although some patients report the pain shifting sides between or during bouts but not during the attack itself.
• Both cluster bouts and attacks during a cluster period can show cyclical periodicity occurring at the same time of year or the same time of day.
• Autonomic features accompanying pain include ptosis, conjunctival injection, lacrimation, rhinorrhoea, nasal stuffiness, eyelid and facial swelling, aural fullness, facial sweating, and redness.
• Most patients become very restless or agitated during an acute attack, unlike people with migraine who often report motion sensitivity during attacks.
• Ninety percent of patients will have episodic cluster headache, which consists of attacks lasting from 7 days to 1 year (averaging from 2 weeks to 3 months), separated by remission periods lasting at least 1 month.
• The chronic form of cluster headache is seen in approximately 10% and consists of attacks that occur for more than 1 year, with less than 1 month’s remission.
• The condition may be chronic from onset or may evolve over time from the episodic form.

Question 2

What is the aetiology of a cluster headache?

Answer 2

• Unknown
• History of head trauma, heavy cigarette smoking and heavy alcohol intake all associated though no causal relationship found

Question 3

What is the epidemiology of cluster headaches?

Answer 3

• One of few primary headaches that affect men predominantly
• Age of onset: 20-40 yrs usually

Question 4

What are the risk factors of a cluster headache?

Answer 4

• FHx
• male sex
• head injury
• heavy smoking
• heavy drinking

Question 5

What are the presenting symptoms of a cluster headache?

Answer 5

• Repeated attack of unilateral pain
• Excruciating pain
• Migrainous aura
• photophobia, phonophobia
• lacrimation, rhinorrhoea, and partial Horner’s syndrome
• agitation
  
  • only 7% can lie still during an attack
• nausea, vomiting

Question 6

What are the signs of a cluster headache on examination?

Answer 6

• Lacrimation, rhinorrhoea and partial Horner’s syndrome
• Agitation
• Photophobia, phonophobia

Question 7

What are the primary investigations for a ?cluster headache?

Answer 7

• brain CT scan or MRI
  
  • Reasonable to perform at time of diagnosis to eliminate secondary causes.
  • = normal in primary cluster headache; abnormal results might indicate secondary causes (e.g., tumour, cavernous sinus pathology)
• erythrocyte sedimentation rate (ESR)
  
  • Used to exclude giant cell arteritis in patients over 50 years of age.
  • = normal in primary cluster headache
• pituitary function tests
  
  • ​

Blood tests, including thyroid function tests, luteinising hormone, follicle-stimulating hormone, insulin-like growth factor 1, cortisol, prolactin, testosterone, estradiol, progesterone, glucose, and growth hormone, should be considered at the discretion of specialist.

* = normal in primary cluster headache; abnormalities may suggest secondary causes resulting from a pituitary adenoma

Question 8

Correction of what comorbidity had been found to cause a resolution of cluster headaches?

Answer 8

sleep apnoea

Question 9

What are some secondary investigations for a ?cluster headache?

Answer 9

• polysomnogram
  
  • Useful for patients with a history that suggests sleep apnoea (which has been suggested as being over-represented in patients with cluster headache) and on patients with medically intractable chronic cluster headaches. Can also be performed on those with chronic cluster headaches, although evidence to support this is lacking.
  • = abnormal in patients with sleep apnoea
• ECG
  
  • Used to exclude conduction abnormalities before starting treatment with calcium-channel blocker (i.e., verapamil) or increasing verapamil dose
  • = often normal; conduction abnormalities or evidence of ischaemic changes may alter drug choices