Functional MRI of CO2 induced increase in cerebral perfusion

NMR Biomed. 1994 Mar;7(1-2):29-34. doi: 10.1002/nbm.1940070106.


The sensitivity of MR gradient echo imaging towards CO2 induced changes in cerebral blood flow was investigated in 10 normal subjects. The subjects were inhaling 5% and 7% CO2 and the experiments were carried out at 1.5 T (n = 6) and 2.0 T (n = 5), allowing a comparison of field strengths. Additional experiments were carried out using a higher spatial resolution. The largest signal increases were noted in areas corresponding to larger vessels, but significant changes were also conspicuous in deeper cortical and central grey matter. The changes appeared linearly related to the arterial CO2 tension, within the range of PaCO2 studied. In white matter, the changes were not statistically significant.

Publication types

  • Comparative Study

MeSH terms

  • Administration, Inhalation
  • Adult
  • Brain / anatomy & histology
  • Brain / blood supply*
  • Brain / drug effects
  • Carbon Dioxide / administration & dosage
  • Carbon Dioxide / pharmacology*
  • Cerebrovascular Circulation / drug effects*
  • Cerebrovascular Circulation / physiology*
  • Female
  • Humans
  • Image Processing, Computer-Assisted
  • Magnetic Resonance Imaging / methods
  • Male
  • Models, Biological
  • Partial Pressure
  • Perfusion
  • Time Factors


  • Carbon Dioxide