Why operate on turned
eyes?
Surgery for turned eyes aims to improve the alignment of the
eyes, that is make the eyes "look straight".
The benefits of
surgery for squint are:
- Improved appearance (often)
- Increased peripheral (side) vision (often)
- Improved depth perception (sometimes)
Alternatives to
surgery may include:
- Glasses
- Exercises (occasionally)
- Do nothing (i.e. leaving the squint alone)
These alternatives should have been discussed and tried (if
appropriate) before undertaking squint surgery. If you feel you do
not understand the place of alternative treatment please ask.
When not to operate
on turned eyes.
- If you are unwilling to accept the risks associated with squint
surgery outlined below.
- If you do not understand why the operation is being done or do
not understand the risks involved.
- If the chance of improving the alignment of the eyes is
low.
- If your child is longsighted and glasses work well to control
the turned eyes.
Risks of surgery for
turned eyes.
There are risks that are related to the general anaesthesia
required and risks specific to the eye surgery.
General anaesthesia risks
- The risks related to the general anaesthesia should be
discussed with the anaesthetist on the day of surgery. The
anaesthetic plan is designed to minimise risk and distress.
- The risk of serious harm occurring to your child during the
course of an elective general anaesthetic is extremely low (of the
order of 1 in 200,000).
- Transient problems, e.g. sore throat, bruise at IV site,
contribution to nausea and vomiting, getting upset, etc are more
common.
- If your child has another significant medical problem these
risks may change. The significance of general conditions should be
discussed with your child's anaesthetist.
Specific risks related to the squint operation itself
include:
- The operation may not produce the desired effect (that is the
eyes are not well aligned). The magnitude of this risk varies with
the age of the child and the type of squint that is present. In
virtually all cases this problem can be treated by undertaking
another squint operation. This is the most common risk of squint
surgery. An estimate of the size of this risk will be given for
your child as part of the process of consent for surgery. In about
1 in 500 - 1,000 cases this problem occurs because the stitch(es)
used to reattach the muscles to the eye loosen.
- Infections are uncommon. About 1 in 150 children experience a
mild surface infection (conjunctivitis) that will require topical
antibiotic eye drops to settle. More serious infection at the site
of the surgery, in the socket or in the eye itself is very
rare.
- Loss of sight following a squint operation is extremely rare
occurring in 1 in 20,000 cases.
- Problems with wound healing occur occasionally (1 in 100's).
This may be evident as a pink lump (granuloma) or white strand of
tissue (prolapsed connective tissue). These problems usually settle
without any specific treatment. Rarely an operation is required to
remove the lump. Rarely there may be a small visible scar or cyst
at the site of the operation.
- Double vision is common after operations for turned eyes. In
most children this is quite transient. Occasionally in older
children (over 10 -12 years old) the double vision is more
persistent. It is extremely rare for this to be a major problem. In
theory further surgery may be required if the double vision does
not settle.
How is the surgery
actually done?
Once your child is asleep the skin around the eyes and the
surface of the eye is cleaned with disinfectant (Betadine). The
eyelids are then held apart with a small clamp and the eye rotated
so that the muscle that is to be operated on is accessible. The
tissue (conjunctiva) over the white of the eye is then cut open
with scissors to expose the muscle and then the muscle is either
weakened or strengthened. The muscle is reattached to the eye wall
with a suture (thread). The opening in the conjunctiva may or may
not be sutured. This process is repeated for each muscle that is
operated on.
What do I
tell my child before an operation?
Most children do not need a detailed explanation of what is
involved in an operation but need to have questions answered
honestly, for example: "Yes, your eyes will be a bit sore after the
operation." Children want to know they will not be left alone and
that you will be there when they wake up. It is a good idea to tell
your child that s/he will meet several different people during
their visit to hospital (receptionists, nurses, orderlies,
anaesthetist and surgical assistant). Being positive about the
visit to hospital and operation will help your child.
What to do before you leave home on the day of the
operation.
- Make sure you understand the fasting instructions and know what
time you have been asked to come to hospital.
- Dress your child in loose clothing (does not need to be
pyjamas).
- Bring a favourite toy or books etc to comfort your child.
- Pack a towel and container in case your child vomits on the way
home.
- Make sure you have a supply of paracetamol appropriate for your
child.
Arrival
in hospital
After completing admission paper work your child will be
assessed by nursing staff and then seen by the anaesthetist. In
general the order of operating list is from youngest to oldest
child. If your child is having their operation later in the list it
is still vital to arrive on time to see the anaesthetist before the
start of list so that s/he is able to start the list on time and
prevent disruptions during the list. As there is always some
waiting involved bringing some toys or books to keep your child
amused is a very good idea.
Going
off to sleep
In general one parent will be able to go with your child into
the anaesthetic room or operating theatre. Children can be
anaesthetised ("put to sleep") with either gas (given by mask) or
by an injection. Please discuss these different methods of going to
sleep with the anaesthetist during the pre-operative assessment.
Your child will go to sleep quite suddenly and it is not uncommon
to feel a bit helpless and distressed by this. If you feel faint
sit down on the floor. We won't be upset and may not catch you if
you faint while standing!
Waiting!
Once your child is asleep you will be accompanied out of the
anaesthetic room to the waiting room. If you go for a walk while
your child is being operated on please return to the designated
waiting area at the time suggested so that I can speak to you as
soon as the operation is completed. Most squint operations take
between 30 to 70 minutes.
What to
expect immediately after squint surgery.
- You will see your child first in the recovery ward. This is an
area near the operating theatre where your child is closely
monitored by a recovery nurse while they wake up from the
anaesthetic. It is common for children to be connected a monitor to
measure pulse rate and oxygen saturation in the blood. Some extra
oxygen may also be given by mask at this time. Once your child is
more fully awake they will go back to the ward.
- Most children are "grumpy" when they first wake up after squint
surgery. The child may cry, scream and thrash around. This almost
always settles in 10-30 minutes. This occurs because there is some
pain (not severe) and the child is confused, hungry and often
disorientated because of reluctance to open the eyes. After this
initial period of being unsettled most children go to sleep and are
much more comfortable when they next wake up. If your child is
particularly upset an additional dose of pain relief (often
codeine) will be given at this time.
- Vomiting may occur after any operation but is more of a problem
following squint surgery, especially for children over 5 years of
age. The anaesthetist will do a number of things during the
operation to reduce the risk of this. The intravenous line will be
left in place until you leave the hospital in case extra medication
is needed to control vomiting.
What
will the eyes look like after squint surgery?
Most often no patch is required. There may be slightly blood
stained tears for a few minutes after the operation and a little
dried blood on the eyelids. This can be washed off with saline or
cool boiled water. The eyes will be blood-shot and appear "bruised"
over the muscle(s) that were operated on and this will increase
over the fist two days after the operation. The redness will go
over 1 - 2 weeks though there may be a persisting pink area on the
white of the eye for weeks to months after a squint operation,
especially if a muscle was tightened (resected). The eyes may
appear much better aligned as soon as they are opened after the
operation. Often there will be noticeable variation in the
alignment with the eyes moving in and out a bit as the brain
"learns" to control the eyes following the surgery. This variation
usually settles in days to a week or so.
Going home
Your will stay in hospital until both you and the nursing staff
are happy for your child to be discharged. This is generally two to
three hours after the operation is finished. If you live more than
two hours drive from hospital it is recommended you stay closer to
the hospital for the first night.
Eating after squint
surgery.
Young children (less than 2 years old) are often keen to drink
immediately after waking. Once the recovery room nursing staff or
ward staff are satisfied your child is sufficiently "awake" you
will be able to offer your child a drink. In older children small
volumes of drinks and then solid food should be offered once your
child is awake. Most older children will only eat small amounts of
food during the afternoon and evening after the operation. Over
feeding soon after the operation may increase the chance of
vomiting in older children.
Pain relief after
squint surgery.
Most children will only require paracetamol for pain relief. For
children younger than one year often no pain relief is needed after
leaving hospital. Pain relief should be given if a younger child
will not settle with soothing and feeding and in an older child if
you believe there is pain. Codeine can be given if the pain is
severe in older children. This may increase the risk of vomiting
slightly. For children having surgery on one eye only an injection
of local anaesthetic may be given to lessen pain after the
operation. Following such an injection the vision will be poor in
that eye for several hours and a patch will be placed over the
eye.
What will the vision be like after the operation?
Often there is some blurring of vision for a few days after
surgery. Younger children will not notice this. Double vision
(diplopia) is common after squint surgery. It is usually quite
transient. A small number of older children (usually over 10 to 12
years of age) will experience more troublesome double vision. Light
sensitivity (photophobia) is common after squint surgery. Older
children will benefit from sunglasses and younger children should
be kept out of direct sunlight for a few days if this seems to be a
problem.\
What care is
needed after the operation?
- Eye drops are occasionally prescribed following squint
surgery.
- Pain relief and eating after the operation are discussed
above.
- The only activity that your child should avoid for about two
weeks after the operation is swimming. Chlorine can be quite
irritating during this time.
- Care should be taken with hair washing as soap and shampoo can
also cause significant discomfort.
- It is common for the eye(s) to be a little sticky after
sleeping for a few days following the surgery. This does not mean
that there is an infection. This discharge can be cleaned away with
boiled water that has been allowed to cool and a cotton ball or
clean face washer.
- Your child can return to normal activities as soon as s/he
feels up it. It is common for children to have a quiet day or so
after any operation.
Potential
problems to look out for after a squint operation.
- The eyes seem to be in an entirely unexpected position, that is
way out of alignment in the opposite direction to that seen prior
to the surgery.
- Copious green or yellow-grey discharge from the eye(s).
- Persistent bleeding that soaks several tissues.
- Persistent severe pain that is not relieved by
paracetamol.
- Marked reduction in vision in one or both eyes.
If any of these problems occur please contact your
ophthalmologist or hospital medical staff promptly.
Post-operative
visits after squint surgery.
The first post-operative visit is generally the next working day
after the surgery and the second approximately one month later.
When
will we know if the operation has been a success?
The best time to judge longer term success is at one month for
convergent squints and six months after surgery for divergent
squints. Unfortunately no matter how successful an operation has
been for a turned eye there is always a small chance of the eye
turning again at some time after the surgery, even many years
later.