Effects of a facial nerve lesion on responses in forehead microvessels to conjunctival irritation and paced breathing

Low-frequency facial hemodynamic oscillations distinguish migraineurs from non-headache controls

Background

Surface imaging is a promising, noninvasive approach to assess regional perfusion in craniovascular disorders such as migraine.

Methods

We used optical imaging to examine differences in facial blood volume at baseline and in response to ammonia inhalation (a noxious stimulus), as well as standardized measures of cardiovascular autonomic function, in healthy, non-headache controls (n = 43) and in interictal migraine subjects (n = 22).

Results

Resting facial cutaneous oscillation (FCO) frequency was significantly different in migraine compared to healthy controls. Following ammonia inhalation, healthy controls showed a significant increase in resting FCO frequency, whereas this response was not significant in the migraine group. Standardized autonomic reflex parameters did not differ significantly between study groups, and facial cutaneous activity did not correlate with standardized cardiovascular autonomic reflex parameters, suggesting potentially different regulation.

Conclusions

This approach to the assessment of craniofacial hemodynamic function appears to exhibit differing mechanisms from previously available techniques, and represents a promising new physiological biomarker for the study of craniofacial vascular function in migraine and potentially other craniovascular disorders.