Fourier analysis of cerebrospinal fluid flow velocities: MR imaging study. The Scandinavian Flow Group.
An interleaved pseudocinematographic FLASH (fast low-angle shot) sequence with additional pulsed gradients for flow encoding was used to quantify cerebrospinal fluid (CSF) flow velocities and CSF production. Flow-dependent phase information was obtained by subtracting two differently encoded phase images. The phase information in the resultant image was converted to flow velocity with a calibration curve with the slope 26.5 radian.m-1.sec. The velocity versus time function was Fourier transformed and a continuous curve was fitted to the measured data with use of the first three harmonics. The in vivo measurements showed a significant variation in flow velocities in the cerebral aqueduct (range, 6-51 mm/sec). Calculated CSF production was in the range of 0.6-1.2 L/24 h. The present method gives valuable information about CSF hydrodynamics in an imaging time of less than 8 minutes.
Thomsen
C
C
Department of Magnetic Resonance, Hvidovre Hospital, University of Copenhagen, Denmark.
Ståhlberg
F
F
Stubgaard
M
M
Nordell
B
B
D000328:Adult; D002535:Cerebral Aqueduct / Q000033:anatomy & histology; D002555:Cerebrospinal Fluid / Q000502:physiology*; D005260:Female; D005583:Fourier Analysis; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008961:Models, Structural; D012212:Rheology