|
RECENT
TRENDS OF CATARACT TREATMENT
Dr. Davis J. Akkara &
Dr. Ethamma Davis
Westend Eye Hospital.
Cochin 31.
We realize the importance of our eyes only when our vision
reduces or when there is an ailment affecting the eye. Most of
the times the eyes are taken for granted! The most common
cause for reduced vision is cataract.
Cataract is the clouding or pacification of the clear God
given lens within the eye. If the lens of a photographic
camera becomes dirty or opaque, the pictures taken with it
also becomes blurred. Similarly, a person with cataract can
not see clearly. The vision will be like seeing through a
glass pane with a silk curtain or fog in front of it.
Cataract usually affects people above 50 to 60 years of age.
Even new borns and young adults also have cataract though it
is not very common. Injury to the eye, radiation, food habits,
maternal infections during pregnancy, heredity, etc. are known
to cause cataracts. But in majority the cause may not be
known. Cataract can be compared to graying of hair in many
aspects. It can happen at any age; and the cause is unknown.
The medical science is developing so very rapidly that it is
difficult for the common man to get the latest information
always. It is important for a person who has cataract to know
the latest in cataract treatment. Many people with poor vision
suffer unnecessarily and wait for the cataract to mature for
the operation. With the present technology cataract need not
be mature for its removal. In fact cataract operation is safer
when cataract is NOT mature!
Treatment of cataract
Change of the spectacles improves the vision to a certain
extent in the early stages of cataract. As the cataract
advances, change of glasses does not improve the vision. He
can undergo cataract operation at that time.
No eye drops in any system of medicine have scientifically
proved its ability to reduce cataract. The claims that the
medicines work are with out proper reliable scientific
studies. Some doctors do advice medicines for the
psychological effect it has and because it does not do any
harm. Recently a group of vitamins called anti-oxidants have
been reported to slow down progress of cataract. It may be
beneficial to take these vitamins to slow down cataract.
Operation is the only accepted method of treatment for
cataract. Cataract has a diameter of approximately 10 mm. and
so when the cataract is to be removed in one piece the wound
also should be of approximately 10 mm. A plastic lens is
implanted in the place of cataract (intraocular lens) to
regain vision. Commonly done operations are:
1. Cold Phaco with Rollable/ Multifocal IOLs. (High Efficency
Low Energy Phaco)
2. Phacoemulsification with Injectable/ Foldable/ Multifocal
Lens (Commonly called laser operation)
3. Small Incision Cataract Operation (SICS, key hole surgery
with rigid Lens).
4. Conventional Cataract Operation with IOL (Intra Ocular
Lens) implantation.
Cold Phaco with Rollable/ Multifocal Lens
It is the latest technique where the cataract is removed
with a High Efficiency Low Energy Phaco System which is even
less traumatic to the eye than the regular phacoemulsification.
Using micropulses the phaco tip is kept constantly cool,
further reducing the chances of tissue injury. The wound
healing is even faster than phaco and quality of vision is
better because of reduced scaring and faster healing.
Phacoemulsification with Injectable/ foldable Lens
It is the technique of cataract operation where the
cataract is emulsified (made into fine powder) with the help
of a computerised machine using high frequency waves and
aspirated (sucked out) through a needle from within the eye.
Contrary to the popular belief, no laser is used for this
procedure. Lasers for cataract surgery are still under
experimental study and are not yet approved by FDA for regular
clinical use till now. The Lasers have not been found to be
superior to phaco technique. The Intra Ocular Lens is
'injected' into the eye through a similar needle. The size of
the incision varies from 0.9 mm to 5.0mm depending on the type
of the lens implanted. The best results are when the wound is
3 mm or smaller. Only the lenses that are injectable or
foldable go in through these small puncture wounds. Foldable
multifocal IOLs are done only after phacoemulsification. Since
the wound is small, there is no need to apply sutures.
Phacoemulsification eliminates the need for large wound in
cataract operation.
The advantages of phacoemulsification are very apparent.
Stable vision is restored in one or two days. Since the wound
is only the size of a needle puncture, the healing is a lot
faster and the patients can go to work almost the next day.
They can have bath also the next day. However as a matter of
caution some doctors advice rest for about a week. Because the
wound size is small, and because the wound is not "opened"
like in conventional surgery, the chances of infection are
greatly reduced in phacoemulsification. The scar is also very
small and so the anatomy of the eyeball is least distorted.
Since there is no suture (stitch) applied, the irritation due
to suture does not arise.
The Phacoemulsification has its limitations also. Hyper Mature
(Over-ripe) cataracts and certain types of black and hard
cataracts are difficult to emulsify. Only a highly skilled
surgeon will be able to emulsify even hard cataracts. In fact
it is better to operate on a cataract before it is fully
mature.
The Phaco machine is very expensive. The semidisposable phaco
tips and tubings are also expensive. The new generation
injectable lenses also add to the cost of the operation making
the operation expensive. However, the advantages of the phaco
operation outweigh the disadvantages and so more and more
patients opt for phacoemulsification.
Low Cost Phaco/ Manual Phaco/ Key Hole Operation/ SICS.
Small Incision Cataract Surgery(Key Hole surgery, SICS) is a
technique where the cataract is squeezed out manually through
a small incision. The size of the incision varies from 6.00 mm
to 7.5 mm. depending on the size of the cataract. Because the
incision size is larger when compared to machine phaco, one or
two sutures may be required to avoid astigmatism and to get
good vision after operation. The patients will have to take
longer rest as larger incision takes longer to heal when
compared to machine phaco.
It is not worth implanting an injectable lens through a SICS
incision because the injectable lenses are made so that they
can be injected through an incision as small as 2.8 mm. The
incision for removal cataract in SICS is at least 6.00mm. And
so 6 mm rigid lenses which are much cheaper are used in SICS.
The main advantage of SICS is that since no costly machines
are used in this operation and only rigid lenses are used for
implantation, it is cheaper when compared to computerised machine phaco.
The total expense of the surgery comes down with SICS though
the period of rest will have to be longer for wound healing.
Though a little more expensive, the best operation available
today for cataract is Phacoemulsification with injectable
lens. Manual operation is a good operation done at lower cost.
Conventional Cataract Operation with IOL implantation which
gave people with cataract vision after cataract operation with
out thick cataract spectacles was considered a revolution in
1980 s. This type of surgery needed 8 to 10 mm incision for
cataract removal and IOL implantation. Sutures had to be
applied and it took longer to heal and hence longer rest. Our
life has become so fast that few people opt for conventional
surgery because they do not want take long periodsof rest. |
