Transcranial <scp>Doppler</scp> ultrasound validation of <scp>BOLD</scp> ‐ <scp>fMRI</scp> cerebral blood flow relationship

Both modeling approaches successfully linked TCD-derived MCA <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:semantics> <mml:mrow><mml:mover><mml:mi>v</mml:mi> <mml:mo>‾</mml:mo></mml:mover> </mml:mrow> <mml:annotation>$$ \overline{v} $$</mml:annotation></mml:semantics> </mml:math> and BOLD-fMRI responses during hypercapnia. These findings support the use of TCD as a complementary surrogate for CBF in BOLD calibration and cerebrovascular research.