Fluctuating Regional Brainstem Diffusion Imaging Measures of Microstructure across the Migraine Cycle

Area of Science:

• Neuroscience
• Neuroimaging
• Pain Research

Background:

• Migraine pathophysiology remains unclear, especially concerning brainstem involvement.
• Limited knowledge exists on brainstem structure and function immediately preceding a migraine attack.

Purpose of the Study:

• To investigate brainstem structural alterations in migraineurs using diffusion tensor imaging.
• To determine if pain processing regions exhibit changes across the migraine cycle, particularly pre-attack.

Main Methods:

• Diffusion tensor imaging (DTI) analysis of the brainstem.
• Comparison of anatomical measures (mean diffusivity, fractional anisotropy) between 36 migraineurs and 29 controls.

Main Results:

• Migraineurs showed increased mean diffusivity (MD) in the spinal trigeminal nucleus, pons, and midbrain during the interictal phase.
• MD normalized 24 hours before migraine onset, then increased post-attack.
• Elevated fractional anisotropy (FA) was observed in the medial lemniscus/ventral trigeminal thalamic tract throughout the migraine cycle.

Conclusions:

• Brainstem anatomy dynamically changes across the migraine cycle.
• Specific pre-migraine structural alterations may sensitize pain pathways, contributing to migraine attacks.
• Findings highlight the brainstem's role in migraine initiation and progression.