Tc-99m HM-PAO SPECT in migraine between attacks

ABSTRACT

Technetium 99m hexamethylene-propyleneamine oxime(Tc 99m HM-PAO) SPECT brain imaging was performed in patients with migraine without aura(n=32) and migraine with aura(n-29) during the headache-free period. A regional alteration of tracer uptake into brain was observed in 21 cases of migraine without aura (65.6%, 18 cases : reduction, 3 cases : increment) and in 20 cases of migraine with aura(69%, all cases reduction, including 10 cases : hemiplegic or hemisensory aura, 10 cases only visual aura). In most cases(73.3%) of migraine with aura, the areas of decreased tracer uptake was exclusively concordant with the areas of unilateral aura. The concordance between the area of associated focal neurological symptom(aura) and the area of regional hypoperfmion was observed in 9 cases(69.2%) of hemiplegic or hemisensory aura(13 cases). The concordance between the site of headache and the areas of regional hypoperfusion or hyperperfusion was observed in 30 cases(49.2%) of migraine with or without aura. Therefore an impaired regional cerebral vascular autoregulation may exist even during headache free intervals in patients suffering migraine with or without aura. It may be concluded that migraine attacks occur in association with exacerbation of preexisting change of cerebral autoregulation.