migrainous neuralgia

Last edited 03/2022 and last reviewed 01/2023

Previously termed migrainous neuralgia, cluster headache is a primary headache disorder classified with similar conditions known as trigeminal autonomic cephalalgias (TACs) (1).

  • it is probably one of the most painful conditions known to man (1)
    • some women may describe the pain to be worse than pain experienced during childbirth (3)
  • attacks usually cluster together into bouts which may last several weeks (1)
  • acute attacks involve activation in the region of the posterior hypothalamic grey matter
  • may be autosomal dominant in about 5% of cases (2)

Studies have estimated that the one-year prevalence to be as high as 53 per 100,000 adults

  • more common in males with male-to-female ratio of 3:1
    • this figure is much higher in  chronic cluster headache than for the episodic form (15 and 3.8, respectively).
  • onset is usually between the ages of 20 to 40 years (patients as young as 4 years and as old as 96 years can be affected.)
  • around 80% of patients reported that the condition restricted their daily activities (1,4).

Attacks may be triggered by alcohol. Other possible triggers include strong smells such as paints and solvents, nitroglycerine, exercise, and elevated environmental temperature (2,4).

Pain of cluster headache:

  • is maximal orbitally, supraorbitally, temporally or in any combination of these sites, but may spread to other regions
  • during the worst attacks, the intensity of pain is excruciating
  • patients are usually unable to lie down, and characteristically pace the floor
  • pain usually recurs on the same side of the head during a single cluster period

Differential diagnosis (5):

  • despite many distinguishing features, clusterheadache is often misdiagnosed, most commonly asmigraine or trigeminal neuralgia
  • cluster headachecan be differentiated from these and other mimics by
    • its attack duration and associated restlessness
    • can be differentiated from secondary causesof cluster-like headaches by MRI of the brain and, ifrefractory to treatment, by MRA of the head and neck,pituitary laboratory testing, lung apex imaging, and polysomnography

Management (5):

  • possible treatments include first line acute therapies oxygen and sumatriptan, the first line transitional treatment corticosteroids, and the first line preventive treatment verapamil
  • new treatments are emerging, such as non-invasive vagus nerve stimulation and galcanezumab