[Significance and usefulness of SPECT with Tc-99m HMPAO in the diagnosis of hemicrania with aura].

It is generally agreed upon that the attacks of migraine with aura are indicative of abnormal cerebral perfusion, while the permanence of such perfusion abnormalities during the pain-free intervals of migraine remains debated. This study was aimed at assessing: 1) the presence of cerebral perfusion abnormalities also during the interictal phase and 2) the role of SPET with 99mTc HM-PAO to diagnose migraine. Twenty-eight patients (22 women and 6 men), diagnosed as having migraine with aura according to the International Headache Society (Headache Classification Committee criteria), were submitted to SPET studies, within 10 days of the last attack. 99mTc HM-PAO was used as perfusion tracer and a single head rotating gamma camera equipped with a high-resolution collimator was used for data acquisition. The qualitative analysis of SPET images showed slight hypoperfusion areas in 22 of 28 patients (79%). In 12 of 22 patients (55%) a regional correlation was observed between hypoperfusion areas and the neurologic symptoms of aura. The results of the present study are in agreement with the current physiopathologic interpretation of migraine with aura, confirming the instability of cerebral perfusion control, even with instrumental evidence of perfusion abnormalities in the interictal period. Moreover, SPET with 99mTc Hm-PAO seems to be a useful tool in the diagnostic assessment of migraine.