Hydrocephalus is a condition characterized by the excessive accumulation of cerebrospinal fluid (CSF) within the brain ventricles. This buildup of CSF increases intracranial pressure and causes the ventricles to dilate, potentially damaging the brain. Hydrocephalus can be congenital due to genetic factors or acquired later in life due to infections, tumors, or hemorrhages that obstruct CSF flow. Common signs include an abnormally enlarging head size, bulging fontanel, downward eye deviations, and poor feeding in infants. Left untreated, hydrocephalus can cause brain damage or death.
2. A condition in which excessive accumulation of CSF
occurs within the brain.
Buildup of CSF in the cavities (ventricles). The excess CSF
increases the size of ventricles and puts pressure on the
brain (intracranial pressure).
“Hydro” - water, “cephalus” – head.
A condition sometimes known as water in the brain.
NOTE: Hydrocephalus can cause the head to steadily grow
in size. Convulsions may also occur, and it can be deadly if
left untreated.
5. Cerebrospinal Fluid (CSF)
Cerebrospinal fluid (CSF), clear, colorless liquid that fills and surrounds the brain and the spinal cord. CSF is slightly
alkaline and is about 99 percent water. There are about 100 to 150 ml of CSF in the normal adult human body, and
also 50 ml in infants. CSF is constantly produced by the ependymal cells of choroid plexuses within the lateral
ventricle. Approximately 20 ml per hour is the total amount of CSF produced by ependymal cells.
Functions as;
1. Provides a mechanical barrier against shock. When an individual suffers a head injury, the fluid acts as a
cushion, dulling the force by distributing its impact.
2. Helps to maintain pressure within the cranium at a constant level. An increase in the volume of blood or brain
tissue results in a corresponding decrease in the fluid. Conversely, if there is a decrease in the volume of matter
within the cranium, as occurs in atrophy of the brain, the CSF compensates with an increase in volume.
3. Transports metabolic waste products, antibodies, chemicals, and pathological products of disease away from
the brain and spinal-cord tissue into the bloodstream.
Note: Examination of the CSF may diagnose a number of diseases. A fluid
sample is obtained by inserting a needle into the lumbar region of the lower
back below the termination of the spinal cord; this procedure is called a lumbar
puncture or spinal tap. If the CSF is cloudy, meningitis (inflammation of the
central nervous system lining) may be present. Blood in the fluid may indicate a
hemorrhage in or around the brain.
6. Cerebral Ventricles and Ventricular System
Cerebral ventricles - are spaces inside the brain
that produce and circulate CSF.
It is composed of the Lateral Ventricles, third
ventricle, cerebral aqueduct ( or aqueduct of
Silvius), and 4th ventricle.
1. Lateral Ventricles - the largest ventricular space
in the brain.
2. Third Ventricle - long and thin and is located in
the midsagittal plane of the diencephalon.
3. Cerebral aqueduct (aqueduct of Silvius) - forms
the connection between the third and fourth
ventricles.
4. Fourth ventricle - last in line and the ventricles.
7. Cerebral Ventricles and Ventricular System
Ependymal cells – cells that produce the CSF. When they form a structure or form
groups in the ventricles, it is called as choroid plexuses.
Choroid Plexuses - the location in which the production of CSF takes place.
Located in all but one of the ventricles: the lateral, third, and fourth ventricles.
Ventricular system - When referred to altogether, the brain’s ventricles are called
the ventricular system. There are four distinct ventricular spaces: the lateral
ventricle, the third ventricle, the cerebral aqueduct, and the fourth ventricle.
NOTE: Surface area of the ventricular systems of the brain is only measured in
millimeters. Meaning, it has a very limited surface area, only intended for normal
CSF circulation. Any interruption or even small blockage can result in inefficient CSF
flow that causes Hydrocephalus.
8. The Flow of Cerebrospinal Fluid Through the Body
Choroid Plexuses
Lateral Ventricles
Foramen of Monro
3rd Ventricle
Cerebral aqueduct
4th Ventricle
Foramen of Luschka
(Left & Right)
Subarachnoid space
Foramen of Magendie
(Median)
Arachnoid Villi
Venous Drainage system
A large
portion is
absorbed in
the
arachnoid
villi, but the
sinuses,
veins, and
brains
substance
and dura
also
participates.
9. Types of Hydrocephalus
1. Non-Communicating 2. Communicating
Intraventricular or
obstructive.
Caused by a blockage
between the ventricular
and subarachnoid
system, resulting in an
interference of CSF
circulation results in the
excessive accumulation
and build up of CSF.
(impaired
absorption)
Caused by an
interference with
CSF absorption
Called as
communicating
because the CSF
can still flow on the
ventricles but
cannot be absorbed
after it exits the
ventricles.
Other types include: Ex-
vacuo and normal
pressure hydrocephalus.
In this subject MCN, only
communicating and
non-communicating is
the most common cause
in infants and children.
10. Hydrocephalus can be classified as:
Congenital
- Result of inherited genetic
abnormalities.
- Result of pregnancy related
abnormal fetal development.
1. Aqueduct Stenosis from an x-
linked recessive trait.
2. Dandy Walker Syndrome
3. Intrauterine Infections
4. Arnold-chiari syndrome
Acquired
-Factors that develop after birth
1. Tuberculosis, chronic pyogenic
meningitis.
2. Post-intraventricular hemorrhage
3. Posterior Fossa Tumors
(medulloblastoma, astrocytoma,
ependymoma.
4. Arteriovenous Malformation
(AVM), intracranial hemorrhage,
ruptured aneurysm.
11. Congenital Factors
.Cerebral Aqueduct Stenosis
.Dandy Walker Syndrome
.Arnold Chiari Syndrome
.Encephalocele
Acquired Factors
.Infections
.Medulloblastoma
.Ependymoma
.Astrocytoma
.Intraventricular and subarachnoid hemorrhage
HYDROCEPHALUS
Large
Head
Rapid Increase in
Head
Circumference
Sunset
Eyes
Poor
feeding
Scalp veins are
dilated and
markedly
when infant
cries.
Bulging of
Anterior
Fontanel
Pupil unequal
response to
light
Infants
Poor
Growth
Pathophysiology of Hydrocephalus
ALL OF THE
FACTORS HAVE
THE SAME
MECHANISM THAT
RESULTS IN
INCREASED ICP
AND CSF BUILDUP
OR
ACCUMULATION.
12. Congenital Factors
1. Cerebral Aqueduct Stenosis (CAS) – abnormal narrowing of the cerebral aqueduct
. It is the common cause of hydrocephalus.
Factors for having CAS;
There’s an enlarging tumor that compress the surrounding of cerebral aqueduct
(aqueduct of sylvius) (example: Pineal tumor).
An x-linked recessive inheritance, that contributes to the development of a naturally
narrowed cerebral aqueduct or also known as congenital aqueductal stenosis.
Abnormal folding of the neural plate that caused a very narrow neural tube from
birth.
Septum formation of the cerebral aqueduct as a result of gliosis.
*Gliosis - non-specific reactive change of glial cells (immune cells of central nervous
system) in response to damage to CNS. Gliosis is the process of proliferation of glial
cells that resulted in a glial scar that may contribute to the narrowing of cerebral
aqueduct.
13. Congenital Factors
2. Dandy Walker Syndrome - a congenital brain malformation. There’s a cyst
formation near the lowest portion of the skull and near to the 4th ventricle. There is
also an incomplete or absent cerebellar vermis or even corpus callosum.
*Cerebellar Vermis – responsible for regulation of muscle tone, posture and
locomotion. If hydrocephalus progresses and left untreated, older children may
experience unsteadiness, lack of muscle coordination, deficits in muscle tone or
strength, and unstable balance.
*Corpus Callosum – responsible for motor, sensory, and cognitive development.
Malformed corpus callosum may result in developmental delay in cognitive
development, poor responsiveness to touch, poor growth, delays in growth and
development such as walking and talking.
As the cysts enlarge, it may occupy a larger surface area and it can outgrow the 4th
ventricle , that may result in an elevated ICP or intracranial pressure. And this pressure
may cause the dilation of the ventricular system.
14. Congenital Factors
3. Arnold Chiari Syndrome - brain tissues extends in the spinal
canal. Specifically, type 2 Arnold chiari syndrome, whereas
the cerebellum and brainstem extends to the cervical spinal
canal (central canal) that blocks the flow of CSF from the
ventricles to the spinal cord. The blockage of the cervical
spinal canal resulted in the buildup of excessive CSF that
resulted in increased ICP that causes the dilation of ventricular
system. Arnold Chiari Syndrome is a disorder that causes the
brain and spinal cord to join.
15. Congenital Factors
4. Encephalocele – a type of a Neural tube Defect. There is a sac-like
protrusion in the brain and membranes through openings in the skull.
Because the skull did not developed completely.
*This herniation or protrusion of brain tissue may vary in location and may
develop on the CSF pathway, and as it protrudes, it can compress the
cerebral aqueduct and other parts like the central canal and the other
parts of ventricular system.
Other Abnormal formations such as Syringomyelia – a cyst that develops
in the spinal cord central canal (obstructive) and obstruct the CSF
pathway and contribute to the excessive buildup of CSF that later
contributes to the increased ICP.
16. Acquired Factors
1. Infections – Such as meningitis, (inflammation of
meninges), Cytomegalovirus, Toxoplasmosis infections.
The inflammation process caused the cells of CNS (glial
cells) to undergo gliosis or scar formation. With this
reason, the scarring may contribute to the occlusion
and cause an interference in the normal CSF Pathway.
*Intrauterine Infections also contributes to the infection of
fetal CNS, that can cause brain tissue inflammation.
17. Acquired Factors
2. Medulloblastoma - Medulloblastoma is the most
common type of primary brain cancer in children.
It originates in the part of the brain that is towards
the back and the bottom, on the floor of the skull,
in the cerebellum, or posterior fossa. Historically
medulloblastomas have been classified as a
primitive neuroectodermal tumor.
-Medulloblastomas usually found in the vicinity of
the fourth ventricle, between the brainstem and
the cerebellum. Signs and symptoms are mainly
due to secondary increased intracranial pressure
due to blockage of the fourth ventricle, causing
increase ICP and may contribute to the
enlargement of the ventricles.
CT scan, showing a tumorous
mass in the posterior fossa, giving
rise to obstructive hydrocephalus,
in a six-year-old girl.
18. Acquired Factors
2. Ependymoma - An ependymoma is a
tumor that arises from the ependyma, a
tissue of the central nervous system
composed of ependymal cells. Usually, in
pediatric cases the location is
intracranial, while in adults it is spinal.
The common location of intracranial
ependymomas is the fourth ventricle.
This tumor may enlarge and interfere
with the normal CSF circulation on the
4th ventricle.
Ependymoma of 4th ventricle
in MRI. Left without, right
with contrast-enhancement.
19. Acquired Factors
3. Astrocytoma - are a type of Brain tumor. They originate
in a particular kind of glial cells, star-shaped brain cells in
the cerebrum called astrocytes.
Astrocytoma causes regional effects by compression,
invasion, and destruction of brain parenchyma, arterial
and venous hypoxia, competition for nutrients, release
of metabolic end products (e.g., free radicals, altered
electrolytes, neurotransmitters), and release and
recruitment of cellular mediators (e.g., cytokines) that
disrupt normal parenchymal function. Secondary
clinical sequelae may be caused by elevated
intracranial pressure attributable to direct mass effect,
increased blood volume, or increased cerebrospinal
fluid volume that may contribute to hydrocephalus.
Low grade astrocytoma of
the midbrain (lamina
tecti), sagittal T1-weighted
magnetic resonance
imaging after contrast
medium administration:
The tumor is marked with
an arrow. The CSF spaces
in front of the tumor are
expanded due to
compression-induced
hydrocephalus internus.
20. Acquired Factors
4. Subarachnoid hemorrhage (SAH) – is bleeding into the
subarachnoid space. Hydrocephalus (HCP) is a common
complication in patients with subarachnoid hemorrhage. When
Blood and blood clots are present in the subarachnoid space, it may
cause clogging in the arachnoid villi, irritation of cerebral lining,
increasing ICP,
*subarachnoid space is the space that normally exists between the
arachnoid and the pia mater, which is filled with cerebrospinal fluid,
and continues down the spinal cord.
*Most cases of SAH are due to trauma such as a blow to the head,
ruptured aneurysms, and arteriovenous malformation.
21. Acquired Factors
5. Intraventricular Hemorrhage (IVH) – also known as intraventricular
bleeding, is a bleeding into the brain's ventricular system, where the
cerebrospinal fluid is produced and circulates through towards the
subarachnoid space. It can result from physical trauma or from
hemorrhaging in stroke. When Blood and blood clots are present in
the ventricular system, it may cause clogging in the ventricles,
arachnoid villi, irritation of cerebral lining, increasing ICP.
- Brain contusions and subarachnoid hemorrhages are commonly
associated with IVH
* In both adults and infants, IVH can cause dangerous increases in ICP, damage to
the brain tissue, and hydrocephalus. Same mechanism with Subarachnoid
hemorrhage in causing hydrocephalus.
22. Signs and symptoms
1. Large Head (Abnormal Head Circumference) – due to the enlargement
and progressive dilation of the ventricles. Scalp veins are also dilated.
2. Rapid increase in size of the head – because of CSF buildup. Note: CSF
is produced constantly.
3. Bulging of the anterior fontanel – the infant’s skull can compensate for
the increased CSF and ICP by expansion of fetal skull, because the
sutures, and fontanel are not yet closed.
4. Downward deviation of Eyes or Sun-setting eyes – due to increased ICP,
it causes an up gaze weakness due to the compression of the gray
matter of cerebral aqueduct, that is responsible for controlling normal
eye movements.
*Cranial nerves III, IV, and VI are being compressed due to increase ICP,
that forces the eye downward. It also contributes on the inability of the
pupils to dilate and become reactive to light.
23. Signs and symptoms
5. Poor Feeding –sensory and motor abilities are not well developed,
including the hunger and satiety center, swallowing reflex is also
undeveloped.
6. Poor growth – due to malformations in the brain that causes
hydrocephalus, may also contribute to the delayed growth and
development.
Other symptoms that occur in toddlers and other children include:
Headache, blurred/double vision, unstable balance, poor
coordination, poor appetite, irritability, seizures, urinary incontinence,
change in personality, decline in school performance, delays in
growth and development like walking and talking.
24. Signs and symptoms
FOR INCREASED IN INTRACRANIAL PRESSURE:
1. Irritability
2. Confusion
3. Headaches (in adults) - because the head cannot compensate
for the enlargement of ventricles.
Other Signs and symptoms
1. Vomiting without nausea – when the brainstem was affected by a
tumor or a cyst, that triggers.
2. Seizures - as a result of secondary infections.
25. Diagnosis
Cranial Imaging Techniques:
1. Ultrasonography
2. CT-scan
3. MRI / Pressure Monitoring Techniques
Doctors may use a variety of tests including brain scans, a spinal
tap or lumbar catheter, intracranial pressure monitoring, and
neuropsychological tests, to help them accurately diagnose
hydrocephalus and normal pressure hydrocephalus and rule out
any other conditions.
26. Treatment
1. Shunt System Insertion – this system diverts the flow of CSF from
the CNS to other area of the body where it can be absorbed as a
part of the normal circulatory process.
2. ETV or Endoscopy or Third Ventriculostomy - a neuroendoscope
(fiber optic) was inserted to provide visualization of the ventricular
surface. Once the scope is in position, a small tool is inserted to
make a hole in the floor of the 3rd Ventricle , to allos the CSF to
bypass the obstruction, and flow toward the site of resorption
around the surface of the brain.
Incidence of Hydrocephalus occurs 1 out of 250.
29. Medical Management
This can be tried in mild cases of hydrocephalus:
• Acetozolamide: dose of 50mg/day to diminish CSF
production.
*Ependymal Cells are dependent in carbonic anhydrase
enzyme. Acetozolamide inhibits carbonic anhydrase, to
prevent CSF production to manage issues with elevated
Intracranial Pressure.
• Oral Glycerol has been used for the similar purpose.
30. Surgical Management
- Removal of the obstruction (tumor, hemorrhage or cyst) to
the flow of CSF.
- Reduction in the amount of CSF produced through
destruction of a portion of the choroid plexus or a third oe
fourth ventriculostomy.
- Shunt System Insertion (as mentioned earlier)
*Shunting is the most common procedure to be done in the
management of hydrocephalus.
31. Nursing Management
A. Teach the family about the management required for the
disorder.
A1. Assess for shunt malfunction and infection.
A2. Provide Perioperative nursing care
- Assess head circumference, fontanelles, cranial sutures, and
level of consciousness. Check also for irritability, altered feeding
habits, a high pitched cry (indication of a high ICP).
A3. Firmly support the head and neck when holding the child.
A4. Provide skin care to the head to prevent breakdown of skin.
A5. Give small frequent feedings to decrease the risk of vomiting.
A6. Encourage parental-newborn bonding.