Laurie Ackerman, RN, MA, Souheil Haddad, MD, Patrick W. Hitchon, MD
University of Iowa Department of Surgery
Peer Review Status: Internally Peer Reviewed
Creation Date: July 1991
Last Revision Date: July 1991
Neuroscience Nursing Division
Department of Nursing
The University of Iowa Hospitals and Clinics
Why "stereotactic" surgery?
You are considering or are about to undergo a special brain operation called
"stereotaxis." There are a variety of reasons your surgeon may have recommended
this type of surgery. Stereotaxis can be used as a type of operation to get
a small tissue sample from deep in the brain, where the surgeon cannot otherwise
safely do an operation. It may also be used to precisely locate an area to obtain
or aspirate a fluid sample for analysis. If the neurosurgeon suspects you may
have an infection or abscess, he or she would want this fluid sample to determine
what kind of microorganism or "germ" is causing the infection so that you can
be started on the correct antibiotic therapy. Still others have this type of
operation for the insertion of a special catheter into a tumor to irradiate
it from the inside. This is called brachytherapy, and there will be more information
about this later.
There are advantages in having a stereotactic procedure rather than the typical
"craniotomy" operation. There is no risk from general anesthesia since you will
not be under anesthetic for the operation. Since you will be awake during the
operation, the neurosurgeon can closely monitor your neurologic function throughout
the operation. The operation itself is much "smaller," meaning the incision
is not as big, and the opening in the skull bone not as large. This operation
also allows the surgeon to operate on areas that were considered "inoperable"
before this type of surgery was available.
As with any operation, there are some risks. There is a small possibility
of infection. You will be placed on antibiotics to minimize this risk both before
and after the operation. You will have a special head dressing over the operation
area that has to be kept clean and dry. Another potential complication is that
of hemorrhage (bleeding) from the operation, and worsening of your neurologic
status. Neurologic status is a term used to describe your level of alertness,
and the ability to move and feel your arms and legs. During the operation, the
neurosurgeons will ask you to occasionally move your arms and legs, and answer
some questions for them so they can assess or monitor your neurologic status.
They are generally not able to do this if you are under general anesthesia.
Overall, the risks with this type of operation are no different than any other
type of brain operation, and the neurosurgeon will actually be better able to
monitor your condition during this type of surgery.
Preparation for surgery and ring application
Once you and the neurosurgeon have decided on a stereotaxic procedure, the
nurses will help you prepare for the surgery. You will need to have the stereotactic
ring applied. This is a black, ring-shaped structure with 4 pins. The neurosurgeon
will shave 4 areas approximately 2 inches by 2 inches on your scalp where the
pins will be placed. Generally, 2 areas in the temple area, and 2 on the back
of your head will be used. Then the areas will be scrubbed with a cold soap
to sterilize the area and kill any germs. A special numbing medicine called
Lidocaine will then be injected with a small needle into each of the areas to
numb them before the pins are inserted. Many people complain of a burning sensation
as the Lidocaine is injected. This is usually brief, and is the most uncomfortable
part of the procedure for many of the patients.
Once the Lidocaine has taken effect, the neurosurgeon will apply the stereotactic
ring. The nurse will help the surgeon position the ring, and tighten the pins.
Some patients report that they can't feel anything during this phase, and others
feel a slight bit of pressure. If you are experiencing pain, please let the
nurse of surgeon know. You may simply need a bit more time for the Lidocaine
to work. The ring itself will circle your head about at the level of your nose.
It is VERY IMPORTANT that you keep your eyes tightly closed while the
neurosurgeon and the nurse are applying the ring. If you are trying to look
up at the surgeon while the ring is applied, you may "trap" your forehead muscles
above the pins. This could give you a rather "surprised" look since it may pull
your eyebrows up, and could potentially cause problems with closing your eyes
while the ring is on. If that would happen, the 2 front pins would need to be
repositioned. It is generally easier to make sure your eyes are closed the first
Planning CT scan
After the ring is on, a second piece of equipment called a "localizing ring"
will be temporarily placed on the ring on your head. You will then go to the
radiology area for a CT scan with this second ring in place. During the CT scan,
it is very important that you lie absolutely still. The technologists in the
CT scanner will probably tape the ring to the CT scanner headpiece as a reminder
not to move during the examination. The CT scan with the ring on takes longer
than the usual CT scan you may have had before. This is because more pictures
are taken during this type of scan.
The localizing ring will be removed after the CT scan is done, but the ring
with the pins will remain in place until after the operation. Once the CT scan
is done, you may return to your room. The surgeon will take the information
from the CT scan with the localizing ring, and feed it into a computer to determine
a set of coordinates or numbers that determines where your incision and biopsy
will be. With these coordinates, the neurosurgeon will be able to set up some
special equipment so that he or she can target the biopsy needle to the exact
point it needs to go to get the specimen or implant a catheter. This system
is accurate to within 1 millimeter!
Once the neurosurgeon has all the equipment ready, you will be taken to the
operating room. You will need to wear special white elastic stockings called
"Teds" to help the circulation in your legs during the operation. You will also
get antibiotics just before the operation to help prevent infection. The anesthesiologist
will start an IV in your arm if one has not already been started.
Once you are in the operating room, you will be moved over onto a special
table. The ring on your head will be attached to the table so that you cannot
move it during the operation. This is important because everything has been
set up within so many millimeters of measurement, and even slight movement of
your head could change all of this. The anesthesiologist will place some electrodes
on your chest so that he or she can watch your heartbeat and rhythm during the
surgery. They will also place a blood pressure cuff on your arm, and loosely
restrain your wrists on the side of the table.
At this point, you will probably receive your first dose of a sedative medication.
This will help make you relaxed, and perhaps a bit sleepy.
You will be awake during the operation itself, so that the neurosurgeons can
monitor your neurologic status. You will probably hear them talking to you,
and with the nurses and anesthesiologist during the operation. Many times the
medication has the effect of making you amnesic or not able to remember the
operation in clear detail afterwards.
At this point, the neurosurgeons come in and begin their preparations for
the surgery. They may look unfamiliar since they will be wearing coverings over
their faces and hair. They may also be wearing some strange-looking glasses
that help protect their eyes, and help them see during the operation. Your eyes
will be covered for the operation to protect them at this point.
The neurosurgeons will shave your head in the area they are going to make
the incision. They will them scrub your scalp with the same disinfectant soap
they used when the ring was applied. After they are done scrubbing the area,
a special drape will be placed over your scalp which will extend down over your
face. The neurosurgeons will drape around the area they are going to operate
with special sterile towels. This part of the preparations sometimes seems to
take longer than the surgery.
A local anesthetic or numbing medicine called Lidocaine will then be injected
into the scalp where the incision will be. As previously described, this may
cause a burning sensation for a few moments while the medication takes effect.
The incision is then made. Generally, it is about an inch in length. A small
piece of bone is then removed using a special drill. You will be hearing the
noise the drill makes and may feel a few "vibrations" as the piece of bone is
removed. A special ring called an "Arc Ring" is then settled onto the ring already
on your head.
The neurosurgeons have preset the biopsy needle in this arc ring using the
coordinates obtained from the CT scanner and the computer program. The biopsy
is obtained, and sent to the laboratory. Although the brain interprets pain
for the rest of the body, it does not sense pain itself, so the biopsy does
not cause pain. At this point, the major portion of the operation is over.
It is not necessary to replace the piece of bone since the area missing is
so small. You actually do not need to take any special precautions with this
area later on once the incision has healed. The scalp is closed with a few stitches
over the operation site, and the drapes and eye patches are all removed. The
stereotactic ring is also removed at this point. A special head dressing or
"turban" is then applied over your entire scalp. Periodically during the operation
and immediately after, the neurosurgeons will ask you to answer a few question
and to move your arms and legs to assess your neurologic status.
After the operation
After the operation is over, you will be sent to the recovery room for about
an hour. The nurses there will continue to assess your neurologic status and
vital signs. You will probably get another dose of antibiotics and some medication
for brain swelling called Decadron. After your time in the recovery room is
over, you will be sent back to the neurosurgical unit.
On the neurosurgical unit the nurses there will continue to check your blood
pressure, pulse, breathing and neurologic status every 4 hours for several days
depending on your condition. You will usually be asked to sleep with the head
of your bed in a slightly upright position to help with swelling after the surgery.
You may also be placed on a fluid restriction, which means that you will have
a limit on the amount you can drink. Your nurse will explain this to you if
the doctors order it. Your nurse will also explain whether or not you can get
up and walk around after the surgery. Many times, you will not be allowed out
of bed until morning.
You will not be allowed to shower while the head dressing is in place since
getting the dressing wet could increase your chance of developing infection.
Your nurse will provide you with instructions on how to bathe while the dressing
is in place. Your doctor will provide information on when the stitches may come
out. Generally, they remain in place for 10 days after the operation before
they are removed.
If your operation was to obtain a specimen to identify a tumor, the results
may not be available for several days. This time is needed for the pathology
doctors to prepare different types of slides to aid in the diagnosis.
If the surgery was to identify a specific type of organism causing infection,
the neurosurgeons will have a preliminary report soon after the operation, and
a final report in three days. This will enable them to identify the appropriate
antibiotics for your treatment.
If your surgery was to implant special catheters for brachytherapy, please
continue on to the next section for additional information.
Special considerations with brachytherapy
Brachytherapy is the term used to describe radiation of a tumor from the inside
of the tumor. The stereotactic procedure used to place the catheters which will
hold the radioactive source or "seeds" into the tumor is the same as was just
described. The only difference is that you will have the ring applied and the
CT scan the night before the surgery, to give the neurosurgeons and the radiation
oncology doctors time to calculate exactly where to place the catheters, and
the numbers of seeds needed for treatment.
After the operation to place the catheters is finished, you will return to
the neurosurgical unit as described earlier. Later that day or the following
day, the radiation oncology doctors will "load" or place the radioactive sources
or "seeds" into the special catheters. To accomplish this, they will remove
your head dressing, and insert special tubes containing the radioactive seeds
inside the catheter tubes placed in the tumor during your operation. Another
head dressing is then applied, and you will be taken back for a CT scan to check
the placement of the seeds within the tumor. Your doctors will examine this
CT scan to check the placement of the seeds within the tumor. Your doctors will
examine this CT scan to make sure everything is in exact position. You will
not be able to shower while the head dressing is in place since getting the
head dressing wet could produce an infection. Check with your nurse for instructions
on how to go about bathing in this time period.
The radioactive seeds remain in place for the time period specified by the
radiation oncologist. Although the required time varies according to tumor size
and shape, most patients will have the seeds in place for 5 to 7 days. While
the seeds are in place, you will occupy a private room. A health physicist from
the Radiation Protection Office will come to your room periodically to measure
the amount of radiation exposure coming from your implant with a special radiation
monitoring device. Based on these measurements the health physicist will inform
the nursing staff of the necessary precautions your visitors should follow when
visiting your room while your implant is in place. In addition, the Radiation
Protection Office recommends that pregnant women and children under 18 years
of age do not visit patients while the radioactive seeds are in place. Since
the radioactive seeds are encased in metal and have been sealed in the catheters,
no other special precautions are usually necessary. Your urine, stool and other
body fluids do not become radioactive as a result of this treatment.
Nothing that you touch or otherwise come in contact with will become contaminated
When it is time for the radioactive seeds to be removed, the radiation oncologists
will remove your head dressing, and "unload" or remove the seeds sealed in the
tube. The health physicists will then perform measurements to make sure that
all of the seeds have been removed. Once the seeds are removed, no radioactive
material or radiation will remain in your body or room and all radiation precautions
are no longer necessary. The neurosurgeons will then remove the catheters that
held the seeds and place a stitch or two to close the opening if necessary.
These stitches will remain in place for 7 to 10 days. Another head dressing
will be applied and left in place for a few days while the incision heals. You
need to continue to take care not to get the dressing wet until the nurse or
doctor indicates if is safe for you to shower.
If you do not start chemotherapy or radiation for a few days, you may be able
to return home at this time. Again, your doctor will be able to advise you on
this. Your physician or nurse will provide you with instructions about when
the stitches need to be removed when you are discharged. Generally, you will
either report to the neurosurgery clinic for stitch removal, or have your local
doctor take the stitches out. At the time of discharge you will also receive
information about your return clinic appointment and CT scans for medical follow-up.