Measurement of cerebrospinal fluid formation and absorption by ventriculo-cisternal perfusion: what is really measured?

The generally accepted hypothesis on cerebrospinal fluid (CSF) hydrodynamics suggests that CSF is actively formed mainly by the choroid plexuses, circulates unidirectionally along the brain ventricles and subarachnoid space, and is passively absorbed mainly into the dural venous sinuses. CSF formati...

Full description

Saved in:
Bibliographic Details
Published in:Croatian medical journal 2014-08, Vol.55 (4), p.317-327
Main Authors: Orešković, Darko, Klarica, Marijan
Format: Article
Language:English
Subjects:
Absorption, Physiological
Animals
Cerebral Ventricles - metabolism
Cerebrospinal fluid
Cerebrospinal Fluid - metabolism
Cerebrospinal Fluid Physiology and Movement
Cisterna Magna
Humans
Hydrodynamics
Inulin - blood
Inulin - urine
Mathematical Concepts
Measurement
Methods
Perfusion (Physiology)
Perfusion - methods
Citations: Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The generally accepted hypothesis on cerebrospinal fluid (CSF) hydrodynamics suggests that CSF is actively formed mainly by the choroid plexuses, circulates unidirectionally along the brain ventricles and subarachnoid space, and is passively absorbed mainly into the dural venous sinuses. CSF formation rate (Vf) has been extensively studied using the ventriculo-cisternal perfusion technique and the results have been used as the key evidence confirming the mentioned hypothesis. This technique and the equation for Vf calculation are based on the assumption that the dilution of the indicator substance is a consequence of the newly formed CSF, ie, that a higher CSF formation rate will result in a higher degree of dilution. However, it has been experimentally shown that the indicator substance dilution inside the CSF system does not occur because of a "newly formed" CSF, but as consequence of a number of other factors (departure of substances into the surrounding tissue, flowing around the collecting cannula into the cortical and spinal subarachnoid space, departure into the contralateral ventricle, etc). This technique allows "calculation" of the CSF formation even in dead animals, in an in vitro model, and in any other part of the CSF system outside the ventricles that is being perfused. Therefore, this method is indirect and any dilution of the indicator substance in the perfusate caused by other reasons would result in questionable and often contradictory conclusions regarding CSF formation rates.
ISSN:0353-9504
1332-8166
DOI:10.3325/cmj.2014.55.317