Epicrania Fugax with a Novel Sign: Pain Paroxysms with Parallel Forward or Backward Trajectories

Epicranial headaches part 2: Nummular headache and epicrania fugax

BACKGROUND

Nummular headache and epicrania fugax are two primary headaches that fall under the heading of epicranial headaches.

METHODS

This article reviews the epidemiological and clinical features of nummular headache and epicrania fugax, proposed pathogenic mechanisms and state-of-the-art management, according to the literature.

RESULTS AND CONCLUSIONS

Nummular headache and epicrania fugax are generally viewed as rare headache disorders, but no population-based epidemiological data are available. Nummular headache is characterized by continuous or intermittent head pain, which remains circumscribed in a round or oval area of the scalp, typically one to six centimeters in diameter. Epicrania fugax manifests with brief paroxysms of pain that move along the surface of the head, following a linear or zigzag trajectory through different nerve territories. Nummular headache and epicrania fugax are mostly primary headaches, but some secondary cases have been reported. The pathogenesis of these headaches is not fully understood. Nummular headache could probably originate in epicranial tissues or adjacent intracranial structures, while the origin of epicrania fugax could be extracranial or intracranial. Diagnostic assessment requires careful examination of the symptomatic areas. Underlying disorders should be excluded by additional investigations, including neuroimaging and appropriate blood tests. No controlled clinical trials have been conducted in nummular headache or epicrania fugax. Analgesics and anti-inflammatory drugs, botulinum toxin and gabapentin are currently the most recommended treatment options for nummular headache. In epicrania fugax, the most used treatments are gabapentin, lamotrigine, and other antiseizure medications.

Epicrania fugax: Report of eight cases with some novel features

Introduction:

Epicrania fugax (EF) is an epicranial headache syndrome characterized by short lasting headache paroxysms which spread in a typical linear/zigzag pattern. The definition of EF has evolved over time, and new phenotypes have been observed in various studies.

Aim:

We present eight cases diagnosed as EF according to the International Classification of Headaches Disorders, 3rd edition criteria and highlight certain novel characteristics which will help in the further categorization of this disorder.

Methods:

We prospectively studied eight cases of EF who presented to our headache clinic from January 2016 to September 2020. Demographic and detailed clinical data were collected and analyzed.

Results:

The mean age of onset of the cohort was 42 ± 10.47 years with a median duration of symptoms being 1 year. There were 5 male and 3 female patients. The mean visual analog scale score was 5.25 ± 1.83. Headache frequency had high intra and interindividual variability. Four patients had a typical spread of pain along the distribution of greater occipital, and supraorbital, nerves. Four patients had an atypical presentation with midline headache, transverse occipital, and bilateral simultaneous hemicranium involvement. Headache paroxysm was followed by a prolonged fixed pain in the same linear distribution in three patients. One patient had ipsilateral redness in the eye. All eight patients required medical intervention with amitriptyline or neuromodulators, five of whom reported a significant reduction in their headache symptoms.

Conclusion:

Our case series highlights a few interesting features which need further exploration with larger studies. Firstly, the atypical distribution of the pain trajectory forces us to dig deeper into the pathogenesis of the disorder. Secondly, our data also suggest a possibility of EF triggered “linear headaches.” EF is a relatively uncommon headache disorder that can be managed easily with neuromodulators but the lack of awareness of the condition often leads to delayed diagnosis.