Structural Magnetic Resonance Imaging of Post-Traumatic Headache: A Systematic Review

To evaluate the available studies on structural magnetic resonance imaging (MRI) of post-traumatic headache (PTH).

A systematic search of PubMed and Embase databases (from inception to February 1, 2024) identified nine relevant structural MRI studies. These studies included adult participants diagnosed with acute or persistent PTH in adherence with any edition of the International Classification of Headache Disorders. Eight studies focused on PTH attributed to mild traumatic brain injury (TBI), while one examined PTH after whiplash injury. The comparison groups consisted of healthy individuals, people with mild TBI (without PTH), and/or individuals with migraine. The eligible studies assessed brain morphometry (n = 7), both cortical morphometry and diffusion tensor imaging (n = 1), or used structural brain images for machine learning (n = 1). The main findings indicated alterations in brain regions involved in affective pain processing and cognitive functions. However, the results were largely incongruent, likely due to small sample sizes and methodologic issues. Structural MRI has shown alterations in the brains of people with PTH, particularly in regions responsible for affective pain processing, cognitive control, and visual processing. These findings align well with the clinical features commonly observed in PTH. Nevertheless, most findings were inconsistent across studies, highlighting the need for methodologic standardization and investigations with larger sample sizes.