Phacoemulsification is the
current method of choice for performing cataract
surgery. The whole operation is done through a small
incision of less then 3 mm – a marvel of scientific
What is it done for?
Cataract is the condition where the natural lens of the eye develops opacity that leads to blurring of vision. When the decrease is vision is problematic enough to cause disturbance in routine life activities, the Phacoemulsification surgery can be performed for visual recovery. In some selected case this may also be done for refractive or presbyopic correction. Click here to read more about Cataract Diseases.
Who is a good candidate?
Anyone with significant cataract and without any uncontrolled systemic or complicating condition is a suitable candidate. Individuals with systemic conditions like diabetes, high blood pressure or heart disease should first have their systemic disease managed by a concerned specialist before going in for cataract surgery. It is also desirable to get a written clearance and any special instruction from the treating physician.
What are the benefits?
Phacoemulsification leads to
rapid recovery of vision and early rehabilitation to
normal life. It is a comfortable and convenient
surgery. In most situations the patient does not
need to stay in the hospital for more than a few
hours. There are minimal restrictions or precautions
after surgery and routine normal activities can be
resumed within a day or so.
What are the risks?
Phacoemulsification is a
relatively safe surgery for cataract, however, like
any other surgery complications can occur in
unfortunate circumstances. Many a times these
circumstances are beyond human control. Some of the
common and important complications are:
Rupture of posterior
Prolapse of vitreous
displacement of lens / nucleus or fragments into
displacement of artificial intra-ocular lens
Inadequate support for
lens implantation requiring use of an
alternative type of lens implantation or
postponing or abandoning lens implant
Pain & increase the eye
pressure or glaucoma post-operatively
endophthalmitis which may require injection of
antibiotics into the vitreous or even vitrectomy
surgery. Although extremely uncommon (about 0.01
– 0.03 %) it is the most dreaded complication.
Most cases of endophthalmitis occur because of
infecting organisms from the patient’s own body
and infrequently by infecting agents present in
the fluids used for surgery. There is no way to
predict or completely eliminate the risk of this
complication. People with diabetes are at
Refractive error and
Inflammation or uveitis
TASS or Toxic Anterior
opacity of posterior capsule may be pre-existing
or may develop a few months to years after
cataract surgery. This is not really a
complication but effect of natural healing
process. It can be very easily & safely treated
by YAG Laser Capsulotomuy.
What tests are required?
Some of the preliminary
Blood Sugar (Fasting &
Urine (Routine &
Other systemic tests may be
required depending on the clinical situation or
co-existing diseases. Certain special eye tests are
Detailed eye examination
of corneal curvature)
Ultrasound (A-scan) of
the Eye or Biometry (to calculate the power of
the lens to be implanted)
What is the anesthesia & discomfort involved?
Most cases are operated
under Topical Anesthesia (also called Eye Drops or
Surface Anesthesia) where some anesthetic eye drops
proparacaine or lignocaine are instilled a few times
before the surgery. Some special circumstances or
uncooperative patients may require injection or peri-bulbar
Before the surgery it is important to dilate the
pupil of the eye with use of various eye drops which
may take about 1-2 hours.
The surgery is quite painless, however, the patient
may feel some pressure & touch on the eye. Patient
needs to stare straight up into the bright light of
the microscope through.
What are the alternatives / options?
Following are alternatives:
MICS – Micro-incision
Cataract Surgery is just a minor variation of
above technique where it is possible to operate
through less than 2 mm incision. However, there
seems to be no advantage over a temporally
placed 3 mm incision and the lenses available
till date which can go through less 2 mm
incision are very new and not yet reliable.
SICS – Small Incision
Cataract Surgery is an alternative to
conventional surgery. The incision is large 5-7
mm and the nucleus of the cataract is removed
in-toto. This technique is useful in cases with
extremely hard brown or black cataract or for
mass application for community service.
Non-foldable lens is implanted, however, no
suture / stitch is required
This surgery is performed
through a small incision of less than 3 mm that does
not require any sutures / stitches. The capsule of
the natural lens / cataract is opened with a needle
by a process called rhexis. The hard core or nucleus
is converted into a soft pulp or emulsified with the
help of high frequency sound waves / ultra-sound
delivered through the Phacoemulsification probe.
This pulp is sucked out of the eye while a fluid is
being irrigated into the eye. The soft cortex around
the nucleus is simply aspirated out clearing the
space for implantation of artificial intra-ocular
lens. A foldable intra-ocular lens is loaded on a
special injector and injected / implanted into the
eye through the 3 mm incision.
What are the implants & material used?
Foldable lenses are made of
two types of material – hydrophilic and hydrophobic
acrylic – the latter being better in terms of long
term results and least possibility of posterior
In terms of optical design the intraocular lenses
are of two main types:
Unifocal – The lens is single focal length
which is usually aimed to focus at mid or far
distance. As a consequence the person needs to wear
glasses for reading near print and sometime for far.
However, the quality of vision & contrast achieved
with this lens is far better.
Multifocal – The lens has two focal lengths –
one to focus the far objects and one to focus near
objects. The need for wearing spectacles is
minimized, however, at the cost of loss of some
contrast sensitivity, glare and image quality.
Moreover, these lenses are expensive and need a
period of adjustment after both eyes are implanted
with the same type of lens.
What technology is used?
The technology that works at
the heart of this surgery uses high frequency sound
waves with frequencies 40,000-60,000 Hz
(Ultrasound). These waves are generated by
piezoelectric crystals houses in Phacoemulsification
hand-piece and controlled by the surgeon through a
computerized panel. The machine also uses fluidics
whereby special fluid is constantly irrigated into
and aspirated out of the eye. All good phacomachines
work on the same principles and deliver the same
end-result, the difference being only of different
level of comfort they provide to the surgeon in
terms of ease of use.
How much is the time taken for
surgery, in hospital and for recovery?
takes about 5-20 minutes (in most cases about 15
minutes) except in special or difficult circumstance
where it may take longer. However, the preparation
may take anything between 1-2 hours. It is advisable
to observe the patient for about 2 hours after the
surgery. So total time spent in the hospital is
about 4-6 hours.
What are the precautions & care
before & after the surgery?
The patient needs to instill some antibiotic eye
drops about 4 times a day in both eyes for about 3-5
days before the surgery. Some oral medicines as
pre-medication may be required. The eye surgeon
decides the type of medicines & dosage. The
treatment for any other systemic diseases is to be
continued even on the day of surgery except that
anti-coagulant or blood thinning medicines may have
to be discontinued a few days prior to operation.
Avoid head bath for a few days to 1 week
Avoid rubbing, pressing, massaging, heat, dust, dirt
and bright sun for 1 month (use sunglasses outdoors)
Avoid heavy weights and strenuous physical activity
for 1 month
Avoid swimming and splashing of water on eyes for 1
Continue other treatments advised by other doctors’
e.g. for Diabetes, High Blood Pressure, Asthma, etc.
Patient can resume most of the normal life
activities from the next day
What are the complications?
The complications have
already been detailed above in the risks.
What is the long-term outlook?
Cataract surgery has
excellent long-term results. The lens implanted in
the eye lasts lifetime (there is no expiry of this
lens and it does not need to be replaced except in
rare circumstances of any problem).
However, some patients may develop thickening /
opacity of posterior capsule (a thin membrane on
which the lens is placed) that may interfere with
vision – this is called After-cataract. This can be
easily treated by a short procedure called Nd-YAG
What are the advantages of getting
it done by you / your hospital?
The author has more than 20
years of experience of doing Cataract Surgery and
more than 10 years experience of Phacoemulsification
Surgery. The author has expertise in use of topical
anesthesia (surface or eye drops anesthesia) in more
than 99 % of his cases and an extremely low rate of
complications. The emphasis is more on quality &
finesse an not on irrationally trying out new lenses
/ products which are constantly being pushed into
market by various companies. The author is
conservative in his approach and pays great respect
to human eyes & visual needs of the patient.
Driven by the quest for quality the author has
always worked in institutions that offer facilities
of high standards. The current hospitals where the
author operates have the best of facility,
technology & material for use in eye surgery.
Which Intraocular Lens (IOL) is most suitable for my
People suffering from cataract and planning for
cataract surgery are faced with this difficult
question & a frustrating list of choices. I will
attempt to make it simple, let me start by
explaining a few characteristics of the Intraocular
What is Intraocular
In cataract surgery the natural lens of the eye is
removed. This leads a significant decrease in the
optical convergence power of the eye or
hypermetropia. Intraocular lenses are small lenses
made of polymers and implanted into the eye in place
of natural lens to help focus the light on to
In conventional cataract surgery & in SICS a large
cut / incision is made in the eye to remove the
cataract. This is followed by insertion of a rigid
6.0/6.5 mm lens through the incision into the eye.
These lenses are rarely used these days.
In phacoemulsification the entire operation done
through a small hole of 3.0 mm or less. It is not
possible to implant a rigid lens. This difficulty is
overcome by use of very flexible lenses which can be
folded and loaded in special injectors aninserted
through the small hole into the eye. These are
currently the preferred lens to be used.
(Silicone, Hydrophillic & Hydrophobic Acrylic)
Foldable Intraocular Lenses are commonly made of
silicone or acrylic polymer (hydrophobic or
Silicone was used in older lenses & gave good
optical results in the immediate post-operative
period. But these lenses were somewhat bulky and
lead to severe thickening of anterior & posterior
capsules (membrane covering of natural lens which is
left behind to provide support for artificial
intraocular lens). This lead to deterioration of
vision and required treatment by YAG Laser
Hydrophillic Acrylic lenses are highly flexible and
slim, therefore, can be introduced through extremely
small incisions. They have good immediate visual
results but suffer from tendency to cause thickening
of posterior lens capsule.
Hydrophobic Acrylic lenses are slightly less
flexible and somewhat thicker than their
hydrophillic counterparts. But they are extremely
inert and do not lead to lens capsule thickening.
Due to these properties they are ideal for use in
children, young adults and the eyes predisposed to
inflammation. Being hydrophobic in nature it is
possible to incorporate a color tint to avoid blue
chromatopsia after surgery.
Spheric are the conventional lenses where both
surfaces of the lens are uniformly curved or are
part of a sphere. These lenses have inherent problem
of spherical aberrations caused by excessive bending
of light at the edges.
Aspheric or advanced optics lenses have their
curvatures flattening out towards the periphery or
edge, thereby, minimizing spehrical aberrations.
Aspheric lenses give much sharper vision and better
contrast but due to decreases depth of focus, the
need for reading glasses becomes more urgent. On the
other hand spheric lenses, though lack the sharpness
& contrast to some extent but have better depth of
focus leading to slightly better near vision.
However, almost all lens manufacturers are replacing
their spherical lenses with aspheric.
Monofocal lenses have a single focal length and
unlike the natural lens do not possess the ability
to change the focus. Therefore the patient needs to
wear reading glasses in order to focus at near fine
print. But these lenses provide much better contrast
and image clarity.
Multifocal lenses have 2 foci - a distance and a
near focus. This is achieved by having multiple
optical zones fashioned in the lens in the form of
alternating rings for distance and near. This leads
to splitting of light into distance and near foci.
As a result both the distant and near objects can be
focussed in the eye at the same time. However, the
contrast and sharpness of the vision is reduced
significantly. There lenses are also prone to more
glare and haloes of light during driving at night
So for patients who need sharp vision and better
contrast and do not hesitate in wearing reading
glasses, monofocal lenses are most suitable.
Whereas, those who do not want dependence on reading
glasses but are willing to compormise on contrast
and sharpness of vision, can opt for multifocal
Please note that both eyes should have the same type
of lens - monofocal OR multifocal.
Toric vs. Non-toric
Toric lenses, besides having spherical power, also
have cylindrical power which corrects astigmatism
present in the eye. Non-toric lenses do not have any
cylindrical power. Eyes with no or negligible
astigmatism require non-toric lens and the eyes with
significant astigmatism would benefit from toric
lenses. Toric lenses are especially useful in
patients with high degree of against the rule
corneal astigmatism which is not amenable to
correction but incision placement.
My preferred lens
Currently I prefer to use Foldable Hydrophobic
Acrylic Aspheric Monofocal Lens with a natural color
tint and toric where required. Multifocal is
preferred where cosmetic requirements is more
important and there are no critical visual needs.
Author: Dr. Sanjay Dhawan
Last Updated on: 1 March, 2014