The following excerpt is taken from Chapter Two of Hydrocephalus:
A Guide for Patients, Families, and Friends by Chuck Toporek &
Kellie Robinson, copyright 1999 by O'Reilly & Associates, Inc. For
book orders/information, call 1-800-998-9938. Permission is granted
to print and distribute this excerpt for noncommercial use as long
as the above source is included. The information in this article is
meant to educate and should not be used as an alternative for
professional medical care.
By the time you receive the diagnosis for the condition of
hydrocephalus, it is likely that you or your child have already
been through a gamut of tests.
This first of a three-part series describes the process of
being diagnosed with hydrocephalus. Articles include:
With newborns, hydrocephalus is detected almost immediately as the
child's head may be larger than normal or misshapen. However, with
older children or adults, hydrocephalus usually starts to reveal
itself with a variety of signs and symptoms weeks or months before it
Common symptoms of an increase of intracranial CSF pressure include:
- Abnormally large head or increased head growth in infants or
- Frequent headaches, particularly late at night or early in the morning.
- Awkwardness or stumbling when walking (gait disturbance).
- Vision problems, including double vision (diplopia).
- Concentration or mental difficulties.
- Nausea or vomiting.
- Neck pain.
Persons with hydrocephalus might not have all of these symptoms. With
infants and small children, the most visible symptom will be
macrocephaly. In teenagers and adults, headaches, gait disturbance,
and concentration and mental difficulties are likely to be more
In order to help your doctor or neurosurgeon diagnose the condition
quickly, keep track of symptoms that you observe on a daily
basis. Keep a notepad handy and write down the symptoms that occur,
noting the date and time they happen. This information helps your
doctor or neurosurgeon see if there is a pattern to when certain
symptoms occur, and can prove to be quite valuable in evaluating the
Abnormal head growth
With infants and small children, the primary indicator that
hydrocephalus could be present is an abnormally large head
(macrocephaly). Unlike adults, the sutures of a child's skull aren't
fused together. It is important for your pediatrician to track the
growth rate of your child's head to ensure that the slow progression
of macrocephaly can be detected early. If left undetected and
untreated, your child's skull could continue to expand because of
abnormally large ventricles (also known as ventriculomegaly).
Macrocephaly can cause the following signs and symptoms:
- High-pitched crying or screaming.
- Split sutures of the skull.
- Distended veins in the scalp.
- Bulging or widening of the fontanels that would cause the head to be
- Absence of upward gaze, which is known as sunsetting; most
frequently present in the instance of acute non-communicating
- Impaired lateral gaze (sunsetting of one or both eyes).
- Loss of vision.
- Weakness or spasticity of the limbs.
Head sizes for male and female infants grow at different rates. Your
child's pediatrician should have current head growth charts for each
sex, not one chart that offers a median value for both. With infants
who were born prematurely, head size should be charted by age
according to conception, not by birth age. Your child's pediatrician
should continue to chart and monitor the growth of your child's head
until he reaches six or seven years old.
My son was five months old when they started thinking it was time
to shunt him; his head circumference had been borderline since
birth but it was at that age it really took off in size.
If you notice the head of your child is abnormally large, it is
advisable to seek medical attention as soon as possible. Keep in mind
that head size is something that is attributable to many causes; if
both parents have large heads, it could be possible that your child's
head size is genetically determined and normal. When in doubt, check
Since my daughter was two weeks old, I had been going to her
pediatrician complaining that something was wrong with her. They told
me it was colic. We lived with that explanation for some time, then
they told me it was probably a reaction to her formula. Again, we
bought that for a while. The only symptom our daughter had was
piercing screams in the night and never sleeping ... and I mean never!
The doctor said this was very common, so we tried to go on with our
lives coping with a sleepless child.
When she was around six months of age I asked the pediatrician to
check her head-it looked a little odd-but the doctor said nothing was
wrong and that I was being over-protective and too critical of her.
At 13 months old, she was finally diagnosed with hydrocephalus and
then needed three operations in 18 days.
Headaches are a common symptom of the onset of hydrocephalus,
particularly with adults. Headaches can be caused as a result of
increased cranial pressure (ICP), either within the ventricles or on
the surface of the brain. The actual headache occurs when pressure of
surrounding fluid and brain matter place pressure on blood vessels and
The severity of headaches can range from mild, dull headaches that
come and go intermittently, to ones that are debilitating. It may be
difficult to tell the difference between a regular headache and a
headache caused by increased ICP.
Gait disturbance-a reduction or loss of walking motor skills-is
usually the first symptom in adults. As intracranial pressure
increases, nerve fibers (axons) of the brain become stretched as the
ventricles enlarge. Axons take a long course around the ventricles to
reach the motor cortex in the frontal lobe. Thus, when the ventricles
expand, the axons are stretched, causing ataxia (a lack of control of
If hydrocephalus remains undetected and untreated, a person's gait
will worsen. Gait disturbance can reveal itself as poor coordination,
imbalance, stumbling, falling down for no apparent reason, and even
loss of the ability to walk or stand.
My mom had shunt surgery in March. After about five months, she
started to show NPH [normal pressure hydrocephalus] symptoms
again. She cannot walk or eat, and is semi-conscious, exactly like
before the first shunt surgery. The doctor said she will be fine again
after she has her shunt revision tomorrow. I hope he is right.
Vision problems often occur in patients who have or are developing
hydrocephalus. Increased intracranial pressure can cause the following
- Non- or slow-reacting pupils.
- Sunsetting of the eyes (also known as Parinaud's syndrome).
- Light sensitivity.
- Impaired lateral gaze.
- Rapid, involuntary eye movements (nystagmus).
- Double vision.
Papilledema, swelling of the optic nerve, indicates ICP. If absent,
it does not exclude elevated ICP, as it occurs in the minority of
patients. Papilledema is diagnosed by looking in the eye with an
ophthalmoscope. Symptoms for papilledema include decreased visual
acuity, blurring vision, and light sensitivity. Decreased visual
acuity first presents itself with intermittent light sensitivity that
progresses. If hydrocephalus is not treated promptly, papilledema can
lead to blindness.
Concentration or mental difficulties
Concentration and/or mental difficulties often develop in patients
with hydrocephalus. Unfortunately, these effects can also last well
after shunts have been placed.
Family members will need to help monitor symptoms. Look for any
deviation from normal behavior, such as problems with visual and
spatial relations, short-term memory loss, or difficulty with verbal
and non-verbal problem-solving. Also be alert for signs of
lethargy. For example, you might have a difficult time waking your
child. Or you might notice a change in social activities; she might
become withdrawn and easily lose interest in whatever she's doing.
Initially, hydrocephalus is detected when one or more of the symptoms
of the condition become evident. For example, in an infant, you might
notice that your child's head is bulging or is larger than normal
(macrocrania or macrocephaly). In a small child, you might notice that
your child has painful headaches, gait disorder, or vision problems.
When hydrocephalus is first suspected, your primary care physician
should then refer you to a neurosurgeon for further evaluation and
testing. A neurosurgeon is a doctor trained to operate on the brain,
spinal cord, and other nervous structures of the body. If other
problems are present, such as seizures or vision problems, the
physician should also refer you to a neurologist or a
Before the neurosurgeon orders any tests, such as a CT or MRI scan,
she will likely perform a neurological examination. This exam includes
a history of neurological milestones, and a physical examination to
check for possible neurological deficits. Below are some of the signs
the neurosurgeon will look for as an indicator that hydrocephalus
could be present.
Premature infants are more likely to develop hydrocephalus as a result
of an intraventricular hemorrhage (IVH), which can cause
post-hemorrhagic hydrocephalus. The neurosurgeon will feel the
fontanel, or soft spot on the cranium where the sutures of the skull
are still open, to see if it is fuller than normal. She will also
check the infant's head circumference to see if it is within the
normal range. Fullness of the fontanels and a large head are
indicators that hydrocephalus is present.
Additionally, she will check to see if muscle tone is normal. If an
IVH or hydrocephalus is suspected, the neurosurgeon may first order an
ultrasound of your child's head rather than order a CT or MRI scan.
Full-term infants (from birth through 1 year old)
As with premature infants, your child's neurosurgeon will check the
size of the cranium and the fontanel for fullness. Since your child is
older and more developed, the neurosurgeon will also check his eyes
and reflexes. One of the things the neurosurgeon will look for is
whether or not your child has a startle response. If he lacks a
startle response, it may could indicate loss of sensation to that part
of the body.
As your child grows, some indicators of a possible neurological
deficit are that he is not meeting some of his developmental
goals. These include smiling, crawling, walking, and being able to
Children (ages 1 through 12)
After your child is one year old or older, the neurosurgeon will
examine him to see if he is reaching mental and physical developmental
- Is your child communicating verbally?
- Is your child doing well in school? Has he fallen behind his peers in recent months?
- Does your child have a hard time remembering things?
- Has there been a noticeable change in your child's personality in
the past few weeks or months?
- Did your child begin to show signs of walking by the time he was one
- Is your child's gait steady or unbalanced? Does he tend to drift to
one side when he walks? The neurosurgeon will be looking closely to
see if your child moves symmetrically.
- Can your child balance on one foot?
- With his eyes closed, can your child place both feet together, side
by side, and maintain his balance?
The neurosurgeon will check your child to see if his arms and legs are
strong, or if there is a deficit in one side or the other. She will
test tendon and muscle reflexes, and will also check for any loss of
sensation in the extremities.
By looking into your child's eyes, she will be able to check for
papilledema. The neurosurgeon will place an index finger in front of
your child's face and ask him to follow its movement from side to
side, and up and down. This is to check for possible paresis
(paralysis) of the abducens (or sixth cranial) nerve. The sixth
cranial nerve controls lateral (side to side) eye movements.
The neurosurgeon will also ask your child to walk heel-to-toe with
head up and arms extended, forward and backward, to evaluate his gait
and balance. If he has difficulty performing this test, it could be an
indication that there is pressure on the cerebellum.
The neurosurgeon will check the plantar, or Babinski, reflex. This
reflex test is done by drawing a blunt object, such as the handle of
an instrument, along the outer edge of the foot from the heel to the
little toe. The normal, or flexor, response is to have the toes bunch
together and move in a downward motion. However, if the big toe moves
upward, the result is an extensor response, or Babinski reflex. A
Babinski reflex is a clear indication of some form of brain or spinal
cord disease. It should be noted that infants will normally have a
positive, or upward, Babinski reflex, whether hydrocephalus is present
or not. As a result, the neurosurgeon will probably skip this test
until your child has reached his first birthday.
The neurosurgeon will test finger-to-nose reaction by holding up an
index finger and asking your child to touch his index finger to the
doctor's finger and then his own nose, as quickly as possible. This
test is primarily performed to see if there is any type of cerebellar
impairment on either side of the brain. If he cannot perform this
test, either by missing the doctor's finger or his own nose, it could
indicate the presence of some form of visual impairment (e.g.,
The neurosurgeon will also test for pronator drift. In a standing
position, the doctor will ask your child to close his eyes, then
extend both arms in front, palms up. The neurosurgeon will be looking
to see if one arm wavers or drifts down and to the side, which can be
an indication of injury to the motor areas of the brain.
For teens and adults being tested for hydrocephalus, many of the same
tests will be done as are done for older children.
Radioisotope cisternography, or nuclear cisternogram, is a test often
performed when normal pressure hydrocephalus (NPH) is suspected.
Radioisotopes are used to help the radiologist and neurosurgeon
monitor the flow of CSF within the subarachnoid spaces, ventricles and
the basal cisterns.
In a cisternogram, the patient is injected with anywhere from 85 to
500 microliters (5c) of either radioiodine serum albumin (RISA) or
indium diethlenetriamine pentacetic acid (DTPA) in the lumbar
subarachnoid space following a lumbar puncture. A scintilliscope is
used to scan for the isotopes at various timed intervals to track the
flow of the radioisotope through the shunt system. In a person without
NPH, the radioisotope can be detected flowing into the subarachnoid
spaces and basal cisterns, with little accumulation in the
ventricles. However, if the radioisotope primarily stays within the
ventricles and little or no radioactivity is detected over the
hemispheres of the brain, then NPH can be assumed.
You can expect a brief moment of discomfort during the initial lumbar
puncture; however, the injection of the radioisotope does not hurt.
Ultrasonography uses high-frequency sound waves to outline the
structures within the body. The resulting ultrasound is caused by the
reflection of the sound wave bouncing off the part of the body being
Ultrasound is used to diagnose congenital hydrocephalus in utero (when
the child is still within the mother's womb). Hydrocephalus can be
detected in utero during normal prenatal screening in the 28th week of
pregnancy and sometimes earlier. The obvious indication that
hydrocephalus is present is that the fetus will have an abnormally
When hydrocephalus is detected in utero, the parents will normally be
referred to a pediatric neurosurgeon who will work with the
obstetrician to provide proper care for the mother and unborn child.
Ultrasound is used most often on infants, as their cranial sutures
have not yet joined together. Ultrasound cannot be used once the soft
spot has filled with bone. The primary benefit of using
ultrasonography on infants is that they can be imaged while awake from
portable equipment that can be brought crib-side, unlike CT and MRI
scans which may require infants to be sedated for testing. Although
the ultrasound allows the ventricle size to be measured accurately, it
cannot image the surface of the brain and some of the posterior fossa.
CT and MRI scans
Until the introduction of computed tomography, or CT, scanners in
1971, the only option for imaging the brain of a child or adult was
with traditional X-rays. Diagnosis of hydrocephalus and other brain
malformations was difficult because X-rays do not provide enough
contrast to see the tissues of the brain.
Within a few short years of introduction, CT imagery became a
household word as CT scanners became more common in university and
medical research facilities. Since CT scans provided clearer pictures
of the body's internal organs, tissues and bones, they quickly became
a standard diagnostic tool for surgeons, significantly reducing the
need for exploratory surgery.
Magnetic resonance imaging, or MRI, received FDA approval for
clinical use in the United States in 1985. Instead of using X-rays,
MRIs use radio waves in combination with a magnetic field to create
pictures of the body's internal structures. These images provide a
clearer view of gray and white matter of the brain, as well as the
vascular system. Though expensive, MRIs are the primary diagnostic
test used by most neurosurgeons today.
Preparing yourself or your child for CT or MRI scans
CT and MRI scans are relatively painless procedures, unless your
neurosurgeon orders the imagery to be contrast-enhanced-then you'll
receive an injection or temporary IV, which allows the contrasting
agent to flow into the bloodstream.
On the day of the procedure, arrive at the imaging center 15 to 30
minutes prior to the time of the appointment. This will allow you time
to complete the necessary paperwork and to meet with the technician to
go over medical history. If the imaging series is to be
contrast-enhanced, arriving early will give the technicians extra time
to get an IV started.
If your child is being tested and has any apprehension about the
procedure, ask the technician to explain the test to her. If asked,
most technicians will give children a tour of the imaging console and
of the equipment in the scanner room before the test to help allay any
In order to perform the test, the patient will be asked to disrobe and
change into a surgical gown, and to remove any type of metallic
jewelry. Adults should refrain from wearing makeup or using hair
spray, as these may interfere with the imaging device. Next, the
patient will be asked to lie on the scanner table, which slides inside
the circular drum that houses the imaging equipment, and asked to lie
perfectly still while inside the CT or MRI machine so the images don't
blur. Infants and small children may be given a mild sedative to help
keep them still.
CT and MRI scans take pictures of the complete cranial and
intracranial anatomy, including the subarachnoid spaces and the
structures of the posterior fossa. These pictures, called slices, are
taken in sections laterally (side-to-side) and sagittally
(front-to-back) at different intervals.
How long does a CT or MRI scan take?
With modern scanners, a CT scan can be as quick as a simple two to
five minute procedure, while an MRI series can take as long as an
hour, depending on the type of scan and whether or not enhancement
materials are used. To pass the time, some CT and MRI machines come
equipped with headphones so patients can listen to favorite music
while in the chamber. This can be especially comforting to young
children who receive MRI scans, as the "clunking" noise from the
magnets can be loud and scary.
Risks of CT and MRI scans
Two possible risks for patients who undergo CT scanning are exposure
to radiation and a reaction to the use of iodinated contrast material.
CT scans use low doses of ionizing radiation to do the imaging. The
average CT scan exposes the patient to radiation doses of five to ten
rads (an absorbed dose of radiation) per slice. Although any damage is
a rare occurrence, frequent head CT scans can place the patient at
risk of radiation exposure which can damage the eyes and possibly
cause cataracts. One way of reducing the risk of radiation exposure to
the eyes is a method called angled gantry, in which the CT scanner is
angled away from the eyes, reducing the dose of radiation the eyes
The chance of radiation damage is minimal compared to the benefit of
an accurate diagnosis.
After my daughter had undiagnosed symptoms for a year, I was at my
breaking point and wanted action taken. I went in to see the doctor
and told them to run some tests like a CT scan immediately. Their
response was, "Why expose a child to radiation?"
Dumb question when you are talking about a life. The CT scan confirmed
that she had hydrocephalus since birth. They shunted her immediately.
Another risk of CT scanning is the use of iodinated contrast material,
which is administered intravenously. This type of imaging series is
known as "contrast-enhanced." Although the amount of iodine used is
relatively low, there is a 1 in 10,000 chance of a patient
experiencing anaphylactic shock (an allergic reaction), and a 1 in
40,000 chance of death. Other possible reactions to contrast material
include damage to the kidneys (nephrotoxity) and/or damage to nerve
Since MRIs use powerful magnets to help produce the images, MRIs
should not be performed on patients who have pacemakers or metallic
implants, such as aneurysm clips (more commonly known as brain
clips). Patients with pacemakers should not be subjected to MRI scans
as there is a possibility that the magnetic field of the machine could
render the pacemaker inoperable.
Neurosurgeons sometimes use brain clips in operations on people with
hydrocephalus or who have had tumors or cysts removed. Brain clips
might be used to deal with an intracranial bleed, complication in
surgery, stroke, or even sometimes to attach a ventricular
catheter. However, most brain clips today are made of a non-magnetic
material, so this shouldn't be an issue. If you know you have brain
clips, but are unsure what type of material they are made of, ask your
CT versus MRI: advantages and disadvantages
CT scanning requires patients to remain motionless for the duration of
the test, however the scan may only take two to five minutes. There is
the small risk of exposure to radiation. MRI scans also require
patients to stay motionless during the test, which can last anywhere
from 30 to 60 minutes, depending on the type of contrast or imaging
being done. Since an MRI can take so long to perform, infants and
young children often require sedation so they won't move during the
A concern shared by many families and their doctors is the cost of a
CT versus MRI scan. The average CT scan costs only $300 to $500 to
perform, while an MRI could run as high as $2,000. If cost is a
limiting factor for you, talk this over with your physician before he
orders any diagnostic tests. Also, it is a good idea to check with
your medical insurance provider to find out whether they will cover
the cost of an MRI. Some insurance companies may only cover a portion
of the cost, so it's important to find out what portion you will be
required to pay, if any.
For routine, annual examinations, our insurance company will only
cover 80 percent of the cost for an MRI. However, if the MRI is being
done for an emergency-something they consider a legitimate reason-then
they will cover it 100 percent.
Both CT and MRI have their advantages, but what it really boils down
to is which image will give the neurosurgeon the best view of the
problem he is trying to diagnose. Until there is an accepted and set
standard for the treatment and monitoring of hydrocephalus,
neurosurgeons will continue to differ on their choice of imaging
device. Ask your doctor to explain his thinking on which test to
order. If you have serious concerns, consider getting a second opinion
Although rarely misdiagnosed with today's modern imaging techniques,
the condition of hydrocephalus is occasionally mistaken for benign
extra-axial fluid of infancy, and Alzheimer's disease in adults.
Benign extra-axial fluid of infancy
At birth and for the first few months, the child's head circumference
will be normal, but will suddenly start to grow rapidly over a short
period of time. Since abnormal head growth is an indicator that
hydrocephalus may be present, the child should be referred to a
pediatric neurosurgeon for further evaluation. A CT series of the head
will be ordered to check the size of the ventricles and for the
presence of cysts or tumors.
When CT images return, the neurosurgeon will see that the size of the
ventricles are normal or slightly enlarged, and there is no indication
of an intracranial mass. What they will notice, however, is an
abnormal accumulation of cerebrospinal fluid in the subarachnoid space
(the area between the skull and the hemispheres of the brain). This is
known technically as benign extra-axial fluid of infancy, and can also
be called a benign subdural hygroma, or external hydrocephalus.
In cases of benign extra-axial fluid of infancy, the subarachnoid
accumulation is normally reabsorbed by the time the child reaches 18
to 24 months of age. Once the benign extra-axial fluid has been
detected, your child's neurosurgeon will require follow-up scans to
ensure the fluid accumulation is being reabsorbed by the brain.
Alzheimer's disease is commonly confused with normal pressure
hydrocephalus (NPH), as some of the symptoms of both are the
same. Indicators of NPH include urinary incontinence, gait
disturbance, and dementia-one of the prime symptoms of Alzheimer's
When NPH is suspected in an adult or elderly patient, it is
recommended that a CT or MRI of the head be conducted to evaluate
ventricular size. If scans of the head are inconclusive (i.e.,
ventricles seem to be of normal size), it is recommended that a lumbar
puncture be performed to determine the CSF pressure within the
subarachnoid space. Another test that can be performed to
differentiate between the two is a radioisotope cisternogram to
monitor the flow of CSF within the brain.
Once hydrocephalus is detected, and if shunting is recommended, it is
important to act upon the neurosurgeon's recommendations as soon as
possible. The longer the condition is left uncontrolled, the greater
the risk of neurological damage.
It is your right to ask for a second opinion. Neurosurgery, whether
performed on a child or an adult, has inherent risks and many possible
complications. Ask your neurosurgeon if there is time for you to
obtain a second opinion. If there is, your neurosurgeon should assist
you in finding another neurosurgeon in your area. Your neurosurgeon
should also assist you in arranging the appointment since the medical
records and any CT or MRI films will need to be transferred. If the
neurosurgeon indicates there is some urgency in performing the shunt
placement or revision, ask him if it is possible to have another
neurosurgeon meet with you as soon as possible.
It is in your best interest to make sure that the neurosurgeon
explains hydrocephalus to you clearly, in terms you can understand.
I have gone for third, fourth, and fifth opinions until I found someone
who I could connect with and believe that they were treating my son
like they would treat their own. You have to follow your gut feelings
when it comes to this stuff. We are just parents, many without fancy
medical degrees, but we know our kids. We have that "parental radar"
that goes off when we are concerned... follow that feeling.