Section 29. Disorders of the Nervous System >
Part 3. Acute Deterioration of Neurologic Function >
Chapter 553. Hydrocephalus and Pseudotumor CerebriNicole J. Ullrich
Topics Discussed: cerebrospinal fluid; hydrocephalus; neurology; papilledema; pediatric neurology; pseudotumor cerebri; shunt; shunt infection; ventriculostomy.
Sections: Pseudotumor Cerebri/Idiopathic Intracranial Hypertension, References.
Excerpt:"Hydrocephalus is a condition in which there is an accumulation
of cerebrospinal fluid (CSF) within the ventricles, leading to increased
intracranial pressure. Hydrocephalus may be caused by increased
production, decreased absorption, or obstruction to flow of CSF.
By contrast, ventricular dilatation due to loss of brain tissue
or atrophy is not considered to be hydrocephalus.Typically, cerebrospinal fluid (CSF) is produced at a volume
of 20 mL/hour, or more than 500 mL per day, in the adult.
Total CSF volume in infants is approximately 50 mL, as compared to
approximately 150 mL in normal adults. Cerebrospinal fluid is produced
by active secretion and diffusion predominantly in the choroid plexus,
located in the lateral ventricles and the roof of the fourth ventricle.
Cerebrospinal fluid passes from the lateral ventricles into the
paired foramina of Monro to reach the third ventricle and then along
the cerebral aqueduct into the fourth ventricle. Once in the fourth
ventricle, CSF flows through the midline foramen of Magendie or
laterally through the paired foramina of Luschka into focally enlarged
areas of subarachnoid space known as the basal cisterns, which connect
the spinal and intracranial subarachnoid spaces (Fig.
553-1). Cerebrospinal fluid is in continual flow around the
brain and spinal cord and within the ventricles in a cephalad direction.
Production of CSF is regulated by the enzyme carbonic anhydrase,
and reabsorption occurs within the arachnoid villi in the meninges
into the venous..."
The content above is only an
excerpt. For full access, log into an existing user account below, purchase an annual subscription, or
purchase a short-term subscription to the complete website.
offers pediatrics students,
educators, and practioners access to leading McGraw-Hill texts, interactive imaging
content, exclusive multimedia, and flexible curricular tools.
Timed access to all of AccessPediatrics
24 hours for $29.95
48 hours for $49.95