Aktuelle Neurologie 2009; 36 - P455
DOI: 10.1055/s-0029-1238549

FMRI activation in spontaneous trigeminal neuralgia attacks

M Obermann 1, D Müller 1, E Gizewski 1, Z Katsarava 1, D Holle 1
  • 1Essen

Objective: To determine which supraspinal brain regions are active in the human brain during pain processing in spontaneous trigeminal neuralgia attacks.

Background: Previous research suggested impairment of the trigeminal nociceptive system due to demyelination and/or axonal dysfunction on the symptomatic side close to the root entry zone in the brainstem. The involvement of central structures in the pathophysiology of trigeminal neuralgia is more and more discussed.

Methods: Functional magnetic resonance imaging (fMRI) was performed in a patient with trigeminal neuralgia during repeated spontaneous trigeminal neuralgia attacks in the maxillary division (V2) of the trigeminal nerve on the right side of the face. The patient had more than 50 attacks per day with an average pain rating on a verbal rating scale (VRS) of 7/10. The respective patient did not take any medication on a regular basis prior to the fMRI investigation.

Results: Structures were active during the spontaneous trigeminal neuralgia attack that are typical for human pain processing: bilateral primary and secondary somatosensory cortex and insula with predominance of the affected right side; anterior and posterior cingulate cortex, inferior frontal and dorsolateral prefrontal lobe, cerebellum, inferior parietal lobe and precuneus.

Conclusion: Brain activation during spontaneous trigeminal neuralgia attacks occurs predominantly in regions that are strongly associated with pain processing. The activated regions are comparable to those observed in experimental, externally applied pain input into the trigeminal pain processing system. Specific regions such as the hypothalamus as observed in SUNCT syndrome or cluster headache were not active during the trigeminal neuralgia attack. This underlines the clear distinction of these clinically sometimes very similar syndromes.