Jeff D. Winter1, Jorn Fiestra2,3,
Stephanie Dorner4, Joseph A. Fisher5,6, Keith St.
Lawrence7,8, Andrea Kassner1,9
1Physiology and Experimental Medicine,
The Hospital for Sick Children, Toronto, Ontario, Canada; 2Department
of Medical Imaging, University Health Network, Toronto, Ontario, Canada; 3Department
of Neurosurgery, University Health Network, Toronto, Ontario, Canada; 4Respiratory
Therapy, University Health Network, Toronto, Ontario, Canada; 5Anaesthesiology,
University Health Network, Toronto, Ontario, Canada; 6Physiology,
University of Toronto, Toronto, Ontario, Canada; 7Imaging
Division, Lawson Health Research Institute, London, Ontario, Canada; 8Medical
Biophysics, University of Western Ontario, London, Ontario, Canada; 9Medical
Imaging, University of Toronto, Toronto, Ontario, Canada
Cerebrovascular
reactivity (CVR) caused by a CO2 stimulus may improve the
assessment of childhood cerebrovascular disease. Reliable BOLD-based CVR
measures may be obtained using precise model-driven prospective end-tidal CO2
targeting (MPET). In this study, we adapted the method of MPET of CO2
to anesthetised and ventilated animals. BOLD CVR repeatability was assessed
in nine mechanically ventilated juvenile pigs. We found excellent BOLD-CVR
repeatability (intra-class correlation coefficient > 0.84), which was
similar to baseline ASL cerebral blood flow repeatability. Translation of
this method to pediatric imaging will enable CVR imaging in small children
who require anesthetic for imaging procedures.