Allodynia? Trigeminal Neuralgia? Or Epicrania Fugax?

Allodynia? Trigeminal Neuralgia? Or Epicrania Fugax?

What is Epicrania Fugax?

Epicrania fugax is a primary headache disorder characterized by brief stabbing head pain that rapidly moves in a linear or zig-zag pattern across one side of the head. "Epicrania" refers to head pain, while "fugax" describes the fleeting nature of the attacks.

 

epicrania fugax

 

What are the Clinical Features of Epicrania Fugax?

- Pain lasts 1-10 seconds in each attack

- Follows a fixed trajectory on one side of the head

- Often moves from posterior to anterior towards the ipsilateral eye or nose (anterior to posterior [towards occipital region] is also possible, but less common)

- Ends in a different nerve distribution than it started

- Strictly unilateral

- May alternate sides between attacks

- Autonomic symptoms (e.g. lacrimation, conjunctival injection, rhinorrhea) may follow attacks. These symptoms are ipsilateral to the pain.

- May be triggered by touch, which may cause a misdiagnosis of allodynia or trigeminal neuralgia. However, it usually occurs spontaneously.

- Tenderness may remain between attacks

 

What Does the Pain Feel Like?

Patients describe the pain as "electric shock-like" or stabbing. It starts abruptly and moves rapidly from its point of origin to termination. The trajectory remains the same for each patient but can vary across individuals.

Some common patterns reported are pain originating in the occipital area and moving forward over the parietal area to the eyebrow or eye. Alternatively, pain may start near the eye and radiate backward. The linear or zig-zag pattern is a hallmark.

 

What Causes It?

The underlying cause is not fully understood. One theory is that it results from abnormal firing of sensory nerves in the linings of pain-sensitive intracranial structures. Structural lesions must be excluded using neuroimaging, patient history, and physical exam.

 

Diagnosis and Treatment?

Epicrania fugax is diagnosed based on the distinct clinical features.

According to ICHD-3:

  1. Recurrent stabbing head pain attacks lasting 1-10 seconds and fulfilling criterion B
  2. Pain moving with a linear or zig-zag trajectory across the surface of one hemicranium, commencing and terminating in the distributions of different nerves
  3. Not better accounted for by another ICHD-3 diagnosis.

Preventive medication is typically not needed given the brevity of attacks. Identifying potential triggers that elicit attacks may help some patients.

Keeping a headache diary noting the location, trajectory, duration, and triggers of suspected epicrania fugax attacks is important. See a neurologist for evaluation. Structural problems must be excluded before diagnosis.

 

Final Thoughts

While epicrania fugax is considered an uncommon primary headache disorder, it may be underdiagnosed since the brief attacks may go unreported by patients or assumed to be an existing primary headache diagnosis or a symptom of one (e.g., allodynia caused by migraine). Increased recognition of epicrania fugax will help determine the prevalence.

Back to blog
  • Migraine Attacks Independent of CGRP (cGMP-mediated migraine)

    Migraine Attacks Independent of CGRP (cGMP-medi...

    Cerebral Torque

    A randomized, double-blind, placebo-controlled study published in Cephalalgia investigated whether sildenafil (Viagra), a phosphodiesterase-5 (PDE-5) inhibitor that increases cGMP levels, could induce migraine attacks in individuals with migraine who were pre-treated with...

    Migraine Attacks Independent of CGRP (cGMP-medi...

    Cerebral Torque

    A randomized, double-blind, placebo-controlled study published in Cephalalgia investigated whether sildenafil (Viagra), a phosphodiesterase-5 (PDE-5) inhibitor that increases cGMP levels, could induce migraine attacks in individuals with migraine who were pre-treated with...

  • Migraine Aura vs TIA

    Migraine Aura vs TIA

    Cerebral Torque

    It can sometimes be difficult to distinguish between migraine aura and TIA, especially in cases of hemiplegic migraine, migraine with brainstem aura, or retinal migraine. Pay close attention to the...

    Migraine Aura vs TIA

    Cerebral Torque

    It can sometimes be difficult to distinguish between migraine aura and TIA, especially in cases of hemiplegic migraine, migraine with brainstem aura, or retinal migraine. Pay close attention to the...

  • The Migraine Brain Does NOT Like Routine: Do you want to win the battle or the war?

    The Migraine Brain Does NOT Like Routine: Do yo...

    Cerebral Torque

    Many in the migraine community have heard the common phrase "the migraine brain loves routine." However, a recent study suggests that this advice, while potentially helpful in the short-term, may...

    The Migraine Brain Does NOT Like Routine: Do yo...

    Cerebral Torque

    Many in the migraine community have heard the common phrase "the migraine brain loves routine." However, a recent study suggests that this advice, while potentially helpful in the short-term, may...

  • Cardiovascular Safety of Anti-CGRP Monoclonal Antibodies in Migraine Treatment

    Cardiovascular Safety of Anti-CGRP Monoclonal A...

    Cerebral Torque

    The researchers discovered that 3.1% of participants experienced abnormal ECGs or cardiovascular adverse events. Among these, 1.6% encountered more severe complications, such as cerebellar stroke, spontaneous coronary artery dissection, or...

    Cardiovascular Safety of Anti-CGRP Monoclonal A...

    Cerebral Torque

    The researchers discovered that 3.1% of participants experienced abnormal ECGs or cardiovascular adverse events. Among these, 1.6% encountered more severe complications, such as cerebellar stroke, spontaneous coronary artery dissection, or...

1 of 4