Functional Magnetic Resonance Imaging of Regional Cerebral Blood Oxygenation Changes During Breath Holding

摘要: Background and Purpose —Recently, noninvasive MRI methods have been developed that are now capable of detecting mapping regional hemodynamic responses to various stress tests, which involve the use vasoactive substances such as acetazolamide or inhalation carbon dioxide. The aim this study was assess cerebral blood oxygenation changes during breath holding at 1.5 T. Methods —In 6 healthy volunteers, T2*-weighted gradient echo images were acquired for a total dynamic scanning time 10 minutes alternating periods normal breathing 40-second intervals after inspiration, 30-second expiration, 18 seconds expiration. To quantify relative signal changes, 2.5-minute baseline image sampling with carried out. Results —Repeated challenges durations induced an overall rise in oxygen level–dependent (BOLD) intensities. In general, BOLD intensity increases greatest gray matter nonsignificant white matter. Depending on breath-holding duration techniques, all activated pixels varied from 0.8% 3.5%. Conclusions —The present demonstrates can be detected by means fMRI T. test, short method hemodynamics fMRI, could become useful alternative CO2 test.