MR assessment of cerebral vascular response: a comparison of two methods.
OBJECTIVE
To compare the results and reproducibility of two MR-based methods of measuring the cerebrovascular response (CVR).


METHODS
In eight volunteers, CVR was assessed with two MR-based methods upon a challenge with acetazolamide. CVR was assessed by measuring changes in total cerebral blood flow (TCBF) using phase contrast (PC) MRI, and by measuring perfusion MRI. To assess reproducibility the measurements were repeated after 1 week.


RESULTS
The average CVR with the PC-MRI method was 46% (SD = 16%), and for perfusion MR the measured CVR was 44% (SD = 16%). The coefficient of variation (COV) for PC-MRI was 28%, while perfusion MR had a COV of 26%. The limits of agreement between the two methods were -49% and 45%, demonstrating a lack of agreement between the two methods in terms of CVR estimation.


CONCLUSIONS
CVR estimates based on PC-MRI and perfusion MRI showed reproducibility but a lack of agreement in healthy volunteers. This lack of agreement can be attributed to the different aspects of the CVR reflected by these methods: TCBF reflects changes in CBF, whereas our perfusion MRI method reflects cerebral blood volume (CBV).
Spilt
Aart
A
Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands. a.spilt@lumc.nl
Van den Boom
Rivka
R
Kamper
Adriaan M
AM
Blauw
Gerard J
GJ
Bollen
Edward L E M
EL
van Buchem
Mark A
MA
D000086:Acetazolamide / Q000494:pharmacology; D000293:Adolescent; D000328:Adult; D001810:Blood Volume; D002560:Cerebrovascular Circulation / Q000187:drug effects; D003287:Contrast Media; D005682:Gadolinium; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D015203:Reproducibility of Results; D014665:Vasodilator Agents / Q000494:pharmacology
D003287:Contrast Media; D014665:Vasodilator Agents; D005682:Gadolinium; D000086:Acetazolamide