Brain Ventricles: Our Internal Lake
Silvia Helena Cardoso, MSc, PhD
We have water into our brain and spinal cord. Why? Firstly, to support and cushion them from trauma. Secondly, "to clean" waste products of metabolism, drugs and other substances that diffuse into the brain from the blood.
The liquid of the brain is called cerebrospinal fluid (CSF). The CSF is clear and colorless, containing small amounts of protein, glucose, and potassium and relative large amounts of sodium chloride. Se o crânio for subitamente deslocado, o poder de flutação do líquor serve para reduzir o impacto, reduzindo por meio disso, danos concussivos. Se o cérebro ou os vasos sanguíneos que o irrigam aumentam de volume, o líquor é drenado e diminui a pressão intracraniana, para manter o volume constante.
The
skull is like a "rigid box". When the intracranial
pressure is increased (after brain injury,
or hydrocephalus), the skull may become overfilled with swollen brain tissue,
blood, or CSF. The skull may become too full and increase the pressure
on the brain tissue. The increased intracranial pressure can cause changes
in the patient's responses including agitation, confusion, decreased response,
and coma.
O líquor circula no cérebro e medula espinhal através de cavidades especiais que constituem o chamado sistema ventricular (from the Latin venter, cavity).The cavities are designated as the 2 lateral, the third, and the fourth ventricle.
Os
ventrículos invadem os lobos frontal, temporal e occipital. Por
isso, são considerados em cada ventrículo, três cornos:
um anterior ou
frontal, outro
posterior ou
occipital e,
finalmente, o inferior
ou temporal.
O sistema de cavidades do encéfalo comunica-se com outras regiões
do sistema nervoso, numa perfeita rede de irrigação.
Each
ventricle contains the choroid plexus
(specialized ventricular tissue) that produces cerebrospinal fluid.
Se houver uma obstrução em determinado ponto, o líquor se acumula e comprime o tecido nervoso vizinho de encontro a caixa craniana que o protege. Originam-se assim, casos de hidrocefalia, com sérios prejuízos das funções cerebrais. As cavidades ventriculares ficam excessivamente amplas, devido à estagnação do líquido em seu interior. Com isso, aumenta a pressão intra-craniana (veja Hodrocefalia).
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Circulation
of Cerebrospinal Fluid
Special:
Visible Human: Frozen Anatomical Sections and MRI Sections
of Ventricular System
Disorders of Cerebrospinal Fluid Circulation
Author: Silvia Helena Cardoso, PhD. Psychobiologist, master and doctor in Sciences by the University of São Paulo and post doctoral fellowship by the University of California, Los Angeles. Invited Professor and Associate Researcher of the Center for Biomedical Inofrmatics, State University of Campinas (Unicamp), Brazil.
Reviewed and commented by the neuroanatomist Dr. Norberto Cysne Coimbra , MD, PhD. Neuoanatomist, Neuroscientist, Molecular Biologist. Laboratory of Neuroanatomy and Neuropsichobiology, Department of Morphology, Faculty of Medicine, Ribeirão-Preto USP (São Paulo), Brazil.
Translation: Silvia Helena Cardoso
Center for Biomedical Informatics
State University of Campinas, Brazil
Copyright 1997 State University of Campinas