Assessment of Vasoneuronal Coupling in Migraine Patients Using Higher-Level Visual Stimuli

Abstract

Objective: Vasoneuronal coupling depends on the integrity of neuronal function and vascular reactivity. We assessed the visual stimulus to blood flow velocity changes of both posterior cerebral arteries and middler cerebral arteries by transcranial Doppler sonography in migraine patients during attack free period and control subjects.Materials and methods: Twenty-five migraine patients and 25 control subjects were investigated. Transcranial Doppler monitoring from both posterior cerebral arteries and subquently from both middle cerebral arteries were performed; during 10 cycles of 20 seconds open eyes observing and searching complex moving risual images, and 20 seconds closed eyes to assess blood flow velocity changes.Results: Neither migraine patients or control subjects had significant side to side differences considering the absolute blood flow velocities and relative increase of these velocities. On the PCA's, migraine patients showed lower reactivity to visual stimuli on both sides than that of the control subjects. However, relative increase of blood flow velocity (28.1±6.9, p=0.015) showed statistical differences on the right side in the migraine patients with aura compared to the control subjects (47.8±3.1). In contrast, migraine patients with aura had higher reactivity to visual stimuli on both MCA's than that of control subjects. The relative increase of blood flow velocity on the right side (21.1±3.1,0 p=0.003) reached a significant level compared to the control subjects (15.0±0.6).Conculusions: Our results showed thati the migraine patients with aura had significantly lower neuronal activity in the occipital region and/or lower vascular reactivity on the PCA's in relation to higher-level visual stimuli and higher reactivity on MCA's with lower-level visual stimuli than that of control subjects. This is probably due in part to lower energy reserves and the inability to accommodate increased energy expenditure even in the interictal period.