The formation of cerebrospinal fluid: Nearly a hundred years of interpretations and misinterpretations

Effect of osmolarity on CSF volume during ventriculo-aqueductal and ventriculo-cisternal perfusions in cats

“…Finally, these results contradict the classic hypothesis, and therefore support recently proposed new hypothesis on CSF hydrodynamics (4,14,18), according to which CSF is being permanently produced and absorbed in the whole CSF system as a consequence of filtration and reabsorption of water through the capillary walls into ISF of the surrounding brain tissue. The CSF exchange between an entire CSF system and the surrounding tissue depends on (patho)physiological processes (trauma, ischemia, etc.)…”

“…Also, in isolated brain ventricles no increase in ICP during 190 min was obtained, nor were the ventricles dilatated, which obviously confirmed an absence of active CSF formation (14). Based on our experimental work, we have recently postulated new hypothesis of the CSF hydrodynamic (3,4,18) The experiments were performed on adult cats, unselected for age and sex, ranging in weight from 1.6 to 3.8 kg. All experimental procedures were performed in accordance with the European Directive 86/609/EEC on the protection of animals used for experimental and other 6 scientific purposes, and the Law on Animal Rights and Protection of the Republic of Croatia, with the approval of the institutional Ethical Committee.…”

CSF dynamic analysis of a predictive pulsatility-based infusion test for normal pressure hydrocephalus

“…Alternative or additional pathways for CSF absorption via cranial nerve roots to the lymphatic system, as well as both secretion from and absorption to the capillaries and the interstitial fluid of the brain have been described. [29,30] The ventricles and part of the subarachnoid space is contained within the rigid confines of the skull, and thus interacts intimately with the arterial and venous systems through the fixed total volume these systems can inhabit. The Monro-Kellie doctrine states that any increase in the volume of brain matter, blood or CSF must be compensated for by an equal decrease in the other volumes.…”

Development of hydrocephalus and classical hypothesis of cerebrospinal fluid hydrodynamics: Facts and illusions

“…A series of obtained experimental results cannot be explained based on the classical hypothesis of CSF hydrodynamics (Bulat and Klarica, 2010;Orešković and Klarica, 2010). The formation of CSF (secretion) was conceived as an active process independent of the CSF pressure (see Section -2.1.…”

“…Recent experimental works have shown that the hypothesis regarding CSF circulation is hardly sustainable/explicable (Bulat and Klarica, 2010;Bulat et al, 2008;Maraković et al, 2010;Orešković and Klarica, 2010;Orešković et al, 2002). Since water constitutes 99% of CSF volume (Bulat and Klarica, 2010), and since, by definition, CSF circulation means the circulation of CSF volume, it is apparent that water should demonstrate the dynamics (bulk flow) of the CSF.…”