
experimental studies on cerebrospinal
fluid flow
a mixed suspension of kaolin and lyco-
podium was injected into the cisterna magna
of dogs.  blockade of csf space was produced
successfully in 63 of 75 dogs; in 48 of the 63,
ventricular dilatation of more than interme-
diate degree was observed.
in these hydrocephalic dogs experimental
shunting was performed either between the
lateral ventricle and the lumbar cistern or be-
tween the unilateral lateral ventricle and the
contralateral cerebral subarachnoid space.  uni-
directional, steady csf flow averaged 0.15 ml. per
hour in the cases of the former shunting,
and the flow averaged 0.25 ml. per hour in the
cases of the latter shunting.
csf flow rate from the ventricle toward the
cerebral subarachnoid space was larger when
intraventricular pressure was higher.  this in-
crease in flow rate parallel to increasing pres-
sure probably results from an increase in csf
absorption.  there seems to be an upper limit
of the flow rate as the pressure is raised.
transient reflux of csf flow was induced by
jugular or abdominal compression.
following intravenous administration of hy-
pertonic solutions, csf flow rate decreased
parallel to the fall of csf pressure and re-
gained the original value as the pressure was
recovered.  when the pressure fell as low as
50 mm. of water the flow almost stopped.
