Abstract #0852

Cerebrovascular Reactivity Measured Using Targeted Hypo/Hypercapnia BOLD Imaging at 7T

Alex Bhogal¹, Marielle E.P. Philippens², Joe Fisher³, Jeroen Cornelis Willem Siero¹,⁴, Peter R. Luijten², Hans Hoogduin¹

¹Radiology, UMC Utrecht, Utrecht, Netherlands; ²Radiotherapy, UMC Utrecht, Utrecht, Netherlands; ³Thornhill Research Inc., Toronto, Ontario, Canada; ⁴Rudolf Magnus Institute, University Medical Center Utrecht, Utrecht, Netherlands

Cerebrovascular Reactivity (CVR) is measured using targeted PaCO2 breathing challenges in combination with BOLD-EPI imaging at 7T. While maintaining normoxia, traditional block stimulus response is compared with a uniformly increasing PaCO2 'ramp'stimulus. Ramp results are modeled using sigmoidal and linear functions to obtain more information with respect to CVR dynamics and increase calibration accuracy for signal changes attributable to vessel reactivity.