ASSESSMENT OF THE CO2 RESPONSE BY MEANS OF NON DIFFUSIBLE CONTRAST-MEDIA AND ANGIO-CT IN PATIENTS WITH CLUSTER HEADACHE

We analyzed the possibility of assessing functional vasomotor changes by means of Arm-Brain Circulation Time (rABCT) and Vascular volume ima ges (V-v) obtained with Angio-CT, in basal condition and following CO2 inhalation, in a sample of 48 patients with cluster headache. CO2 inh alation resulted in the appearance of local changes, which were detect ed in 28 regions. Analysis by indicator images of V-v-dependent rABCT distribution showed two main patterns: abnormal rABCT mostly evident a t the smallest V-v pixels and abnormal rABCT dependent on abnormal V-v distribution. The former pattern was linked to abnormality at the cir cle of Willis; the latter to abnormal local vasomotor responses. Patie nts with cluster headache showed both patterns, which prompted us to c onclude for the presence of low-degree stenosis in carotid arteries an d vasomotor instability in peripheral brain vessels. Copyright (C) 199 6 Elsevier Science Ltd.