Molly Gallogly Bright1,2, Daniel P. Bulte2, Peter Jezzard2, Jeff H. Duyn1
1Advanced MRI Section, LFMI, NINDS, National Institutes of Health, Bethesda, MD, USA; 2FMRIB Centre, Department of Clinical Neurology, University of Oxford, Oxford, UK
Recently we introduced a novel respiratory technique, cued deep breathing (CDB), which induces robust BOLD signal decreases. The strong, short-lived response to CDB allows for whole-brain spatial and temporal characterization of cerebrovascular reactivity, and CDB is suitable for a broad range of clinical situations. We have directly compared the quantitative effects on end-tidal gas levels and BOLD signal of CDB and a traditional hypercapnia 4% CO2 gas challenge. CDB induced up to 7.00.7 mmHg decreases in end-tidal CO2 and the resulting reactivity maps show good correlation with the CO2 study, indicating CDB offers easy access to similar information.