during the interictal period and the migraine attack. Increased
baseline flow velocities were recorded in the basal
cerebral arteries in migraine patients with (and without)
aura.5–9 Especially, studies with f-TCD demonstrated altered
interictal cerebrovascular reactivity to several stimuli, such
as CO2,10,12–15 visual stimulation,16–20 Valsalva maneuver,
21,22 or others.23–25 These methods are suggested to reflect
interictal vasomotor changes of pathophysiologic interest
and could be used as a monitoring tool under prophylactic
migraine treatment. However, there have been sparse data
on this. Fiermonte et al.26 reported that an increased reactivity
index to hypocapnia disappeared during flunarizine
prophylactic migraine treatment. In contrast, the cerebrovascular
CO2 reactivity remained unchanged under treatment
with metoprolol,27 whereas acupuncture might
positively influence the cerebrovascular response during visual
stimulation with flickering light.28