Cataract

Structure of the Eye

The construction of the human eye is just like that of a camera. Light rays are focused through the cornea and the lens, on to the retina (The retina is a layer of light sensitive cells at the back of the eye like the photosensitive film of the camera). The retina then transmits the focused images to the brain via the optic nerve. This is seen as a bright clear image.


What is Cataract?

The normal crystalline lens of the eye is clear and transparent. Whenever the lens develops cloudiness or opacity, it is called a ‘cataract’. This opacification obstructs light from being transmitted to the retina causing blurring
of vision. This may be compared to a window that is frosted or fogged with steam.


What Causes a Cataract?


Normal Eye

Cataractous Eye

Most cataracts occur as a result of:

  • Increasing age. The normal process of aging may cause the lens to harden and turn cloudy.

Other less common causes of development of cataract are:

  • Injuries to the eye,
  • Infections or inflammations within the eye,
  • Certain medications
  • Radiation,
  • Diabetes - can accelerate the process of cataract formation,
  • Rarely some children are born with cataracts - as a congenital abnormality
  • Family history - cataract can occur at a much earlier age than otherwise expected, even as early as 20 years.

Symptoms

As the cataract develops:

  • There may be hazy and blurred vision.
  • Double vision and distortion of images may occur.
  • The eye may be more sensitive to light glare, making night driving difficult.
  • Things may seem brighter with one eye than the other.
  • There may be a need to change glasses frequently.

What would happen if cataract is not removed?

Surgical removal is the only treatment of cataract. If not operated, a cataractous lens advances to maturity (becomes more cloudy), and the vision progressively deteriorates. There are visually rapid and erratic changes in glasses. When fully advanced the patient becomes almost blind. If still not operated upon the lens material may cause a rise in pressure in eye (glaucoma), intraocular inflammation and in some cases the support of the lens becomes weak, and the cataractous lens may move from its normal position. These complications may cause permanent damage and affect the final visual recovery after surgery, and also make the surgery technically more difficult.


When should one be operated for Cataract?

When a cataract causes enough loss of sight to interfere with the patient’s routine life style, it is time to remove it. There is no scientifically proven medicine for reducing or dissolving cataracts and hence the only treatment is surgery at an appropriate time. Depending on individual needs, the patient and the ophthalmologist decide together when the cataract should be operated. At this point it may be important to mention that the concept of ‘mature’ or ‘ripe’ cataract for its removal is not necessary. In short, whenever a patient is visually handicapped to carry on his / her daily activities, it is time to consider cataract surgery.

About Cataract Surgery

There are several surgical techniques for cataract removal. The operating surgeon is the best person to decide which technique is likely to yield the best result.

  • Intracapsular cataract surgery: (redundant & obsolete ) The entire lens is removed.
  • Extracapsular cataract surgery: The posterior capsule of the lens is not removed and is left behind to act as a support for intraocular lens implantation. Both these procedures require stitches, which are removed at variable intervals.
  • Phacoemulsification: This technique removes the cataract through a small 2 mm incision in the eye. The cataractous lens is broken into fragments and each of these is then liquefied (emulsified) using ultrasound energy. This technique usually takes 5 minutes, depending upon the density of the Cataract. We are proud to have a pair of high end phacoemulsification system called Infinity with OZIL technology the topmost technological systems with advanced safety features from Alcon, USA. special foldable lenses are inserted through these small incisions.

The LenSx Famtosecond Laser

  • A bladeless cataract procedure
  • Truly customized cataract surgery
  • Reduced risk of complications including blindness and less stress to the cornea (less endothelial cell loss).
  • Better positioning of lens to maximize the visual outcome, while less phacoemulsification ('phaco') energy reduces haze.
  • Replacing some manual steps and the use of a blade (knife) during surgery.
  • Pre-breaking apart of the cataract using the femtosecond laser reduces surgery time and risk.
  • Less phaco energy used results in faster recovery and produces better results.
LenSx Famtosecond Laser
 

Verion Cataract Image Guided System

  • First, measurements and images of your eye are taken non-invasively.
  • Next, your surgeon uses a series of complex calculations provided by the system to tailor and optimize your surgical plan.
  • Finally, your tailored surgical plan is used in combination with the high-resolution images of your eye to help precisely guide every phase of the procedure.
Verion Cataract Image Guided System

CENTURION® Vision System

  • Active Fluidics™ Technology, an automated system that optimizes anterior chamber stability by allowing surgeons to proactively set and maintain target intraocular pressure (IOP) within the eye during the cataract removal procedure.
  • Balanced Energy™ Technology enhances phacoemulsification efficiency through proven OZil® Intelligent Phaco and the INTREPID® Balanced Tip probe. This increases efficiency and control, while reducing energy levels
  • Applied Integration™, an innovative design that enables the new system to be seamlessly integrated with multiple cataract surgical technologies, like Surgical Microscopes and the LenSx® Laser
CENTURION® Vision System
 

CONSTELLATION® TT Vision System

  • ULTRAVIT® High Speed Vitrectomy Probes deliver 7500 cpm dual pneumatic drive technology. This technology has been designed to optimize surgical experience and patient outcomes.
  • Duty Cycle Control - The CONSTELLATION® Vision System allows the surgeon to modify duty cycle to control flow independent of vacuum and cut rate to improve overall efficiency of the system
  • Integrated Pressurized Infusion - The CONSTELLATION® Vision System constantly monitors infusion pressure. The IOP Compensation feature provides control of Infusion Pressure which results in more stable IOP which improves safety during the surgery.
  • The CONSTELLATION® Vision System delivers state of the art illumination for visualizing tissues.
CONSTELLATION® TT Vision System
 

LENSTAR LS 900 Optical Biometer

Optical coherence biometry has revolutionized cataract surgery. Featuring OLCR technology, Lenstar is redefining optical coherence biometry.

The Lenstar provides highly accurate laser optic measurements for every section of the eye - from the cornea to the retina − and is the first optical biometer on the market that can measure the thickness of the crystalline lens. With its integrated Olsen formula, one of the latest generation multivariable IOL calculation methods, the Lenstar provides the user with the best possible IOL prediction.

Dual zone keratometry, with 32 measurement locations or topography measurement with the optional T-Cone, provides reliable and precise measurements for the K values, axis, and astigmatism that are essential to the sophisticated planning of toric lenses. The Lenstar LS 900 offers the optimal planning platform for superior refractive outcomes in cataract surgery, both now and in the future.

Intraocular Lens (IOL)


Acrysof Single

Acrysof Natural

Acrysof Multifocal

Acrysof Toric

The intraocular lens is a small plastic lens powered and designed to replace the human lens and is fitted inside the eye permanently. It may be foldable or non-foldable.

The advantages of an IOL are:

  • It causes no magnification,
  • No distortion of objects,
  • Normal side/peripheral vision,

The IOL is implanted during the surgery after removal of the cataractous lens. The measurement of the power of the IOL to be implanted is determined before the surgery by a simple procedure of ultrasonography (A-Scan Biometry). Unlike contact lenses which require periodic change, intraocular lenses once implanted stay throughout life. By and large they do not need to be changed. It does not cause any awareness of its presence within the eye.


Foldable Intraocular IOL

These lenses are inserted through incisions as small as 2.2mm. Foldable lenses are made of silicone or soft acrylic. As their production involves advanced technology, their cost is higher. All IOLs used today offer protection from harmful ultra violet rays, newer 'yellow lenses' offer additional protection from potentially harmful blue light in visible spectrum.


Types of Lenses

  • MultifoculToric
  • Monofocal: Routinely used for most cases.
  • Multifocal IOL: This reduces the dependency on glasses for both distance and near vision. (However, not all patients are suited for this type of lens and you need to discuss with the doctor about it.)
  • Toric IOL: These lenses are designed to reduce the high cylindrical number.
    (Again you need to discuss with the doctor whether you are best suited for this lens or not.)

How much visual recovery to expect?

Cataract surgery has a very high success rate, over 99% cases are technically successful. It is however important to realize that factors other than technically successful cataract surgery play a very important role in the visual recovery after cataract surgery e.g. the condition of the retina, optic nerve, pre-existing disease, amblyopia (lazy eye), etc. Sometimes it may be difficult to diagnose the abnormality before the surgery because of the dense cataract.


Need for Glasses after IOL Implant

After an IOL implantation, most patients may need to use a small spectacle number for distance vision and an additional number for near vision. The number may or may not change after a few weeks or months. For several reasons it is advisable to adjust the power of the IOL in such a way that patients with a moderate to high refractive error prior to surgery retain a small number after IOL implantation.


Posterior Capsular Opacification (P.C.O.) - also known as 'Chari'/After Cataract

In Modern cataract surgery (including phacoemulsification) the posterior part of the lens (the posterior capsule) is left behind. It is usually clear and forms a support for implantation of the intraocular lens. It may undergo opacification and may hamper vision even after cataract surgery. It is also known as 'After Cataract', Or Chari. It may develop within a few months to few years from surgery, though its incidence is significantly reduced with some foldable lenses. Chari is treated as an OPD procedure by a laser which takes about 1-2 minutes only.

Frequently Asked Questions

When can reading be resumed?

If the other eye has good vision, reading with that eye in moderation, keeping the operated eye covered, can be resumed on the next day.

When can work be resumed?

Work restricted to the office can be resumed after about 3 to 4 days. Dusty environment however must be avoided. Also work involving physical strain must be avoided for up to 1 week.

Can the patient watch T.V.?

The patient can watch T.V. from the day of surgery.

When can exercise be resumed?

Exercise restricted to walking can be resumed from the next day. Any heavier exercises like playing tennis, badminton, yoga, gym-workouts, etc., should be avoided for 2 weeks. Swimming should be avoided for about 4 to 6 weeks

When can travel be undertaken?

With the doctor’s permission, depending on the recovery; but usually after 4 to 5 days.

When can sex be resumed?

Usually in a weeks time.

When can smoking / drinking be resumed?

Usually within a weeks time.

When is hair coloring or dye permitted?

After 15 days.