ABSTRACT
We investigated regional cerebral blood flow (rCBF) with Tc99m-HMPAO single photon emission computed tomography (SPECT) and blood flow velocity in the middle cerebral artery (MCA) with transcranial Doppler (TCD) ultrasound. Nineteen cluster headache patients participated in the study, 9 of them underwent both examinations, whereas in 6 patients only SPECT and in 4 patients only TCD was performed. Patients were examined during spontaneous and/or provoked attacks and when symptom-free in a cluster period. Six patients showed moderate frontal hyperperfusion, 2 had frontal hypoperfusion whereas no change from headache-free rCBF occurred in 7 patients. Statistical analysis of MCA velocities in 13 patients showed a significant decrease in the mean flow velocity compared with the headache-free values on the symptomatic side. Our findings suggest that the alteration of cerebral circulation during cluster attacks might be of secondary nature.
