European Headache Federation consensus on technical investigation for primary headache disorders

Diagnosing primary headache disorders typically relies on clinical criteria. Yet, certain neurological conditions can resemble these disorders, leading to diagnostic uncertainty. Established knowledge includes the International Classification of Headache Disorders (ICHD-3-beta) as the standard for diagnosis. However, gaps remain in determining when imaging is necessary. This uncertainty arises when symptoms suggest a non-primary origin. Features like abrupt headache onset or neurological signs may signal an underlying condition. Prior research has shown that imaging is not always routine for primary headaches. This paper addresses the need for imaging in ambiguous cases. It aims to clarify when brain MRI or other investigations should be considered.

The goal is to provide guidance on when to use technical investigations for primary headache disorders. The authors aim to identify red flags that suggest a non-primary cause. They focus on scenarios where diagnostic uncertainty exists. The motivation stems from the risk of missing secondary causes. The study seeks to standardize imaging recommendations across Europe. It addresses the lack of strong evidence for imaging in headaches. The authors aim to build consensus among headache specialists. This effort supports safer and more consistent clinical decision-making.

The authors compiled a consensus among European headache societies and experts. They reviewed diagnostic criteria from ICHD-3-beta and existing literature. The process included input from national headache societies and the European Headache Alliance. They identified clinical features that suggest secondary causes. MRI recommendations were developed for specific headache types. The consensus was based on expert opinion due to limited evidence. They evaluated when additional tests beyond MRI are necessary. The final recommendations were refined through expert review.

The consensus recommends brain MRI for migraines with persistent aura or brainstem aura. Brain MRI, MRA, and MRV are advised for persistent aura without infarction. MRI with pituitary and cavernous sinus evaluation is needed for TACs. Additional tests are suggested for cough headache and thunderclap headache. The recommendations apply when headache patterns change or neurological signs appear. MRI is advised for headaches that awaken the patient or are postural. The consensus includes cases like hypnic headache and exercise-induced headache. The authors acknowledge the lack of strong evidence and emphasize the consensus nature of the guidelines.

The authors propose that MRI is necessary in specific headache scenarios. They suggest MRI for migraines with persistent aura or brainstem aura. MRI with detailed imaging is recommended for TACs. Additional tests may be needed for headaches like thunderclap or hypnic. The recommendations apply when headache features suggest secondary causes. The authors acknowledge the limited evidence and stress the expert-based nature of the guidelines. They advise caution in interpreting these recommendations due to their consensus-driven basis. The guidelines aim to improve diagnostic accuracy and patient safety.