Cataract FAQ

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How the eye works

Before understanding cataract, it is important to know how a normal eye works. The eye is like a camera. The lens in a camera allows light to pass through and focuses that light on the film at the back of the camera for a clear picture.
The eye works in a similar way. The lens of the eye is normally clear and allows light to pass through. The light is focused on a thin film-like retina, which is situated at the back part of the eye. This is how we see.

 

What is a cataract?
It is a cloudiness of the normally clear lens in the eye. It prevents the lens from focusing light onto the retina and hence causes unclear vision. As the cataract advances, this cloudiness of vision increases over a period of time until the vision is completely impaired.

 

Why does a cataract develop?
Cataract development is part of the normal ageing process. Almost all people above the age of 60 years have cataract of a variable degree, although it can occur at an earlier age also. In some people cataract development is aggravated by an eye injury, presence of diabetes, use of medications or other eye diseases. Rarely cataract may be present in the newborn as a developmental defect.

 

What are the symptoms of a developing cataract?
Because cataracts form in different ways, the symptoms of cataracts are variable. Most people notice that their vision gradually deteriorates - objects may begin to look yellow, hazy, blurred or distorted. Many people also find that they need more light to see clearly, or that they experience glare or haloes from lights at night. A common problem encountered is increasing nearsightedness. In advanced cases, the cataract may be visible as a whitish-looking pupil.

 

Can cataract be prevented or treated with medication?
Cataracts that occur due to the ageing process cannot be prevented as the ageing process itself cannot be prevented. Using the eyes for reading and similar activities has nothing to do with cataract formation. Avoiding the use of eyes will not prevent cataract.


Till date as per all authentic medical research no medication exists to prevent or cure a cataract. The only known treatment for cataract is surgery.

 

When can one undergo Cataract Surgery?
Cataract surgery can be performed as soon as the patient feels handicapped in performing routine activities at work and leisure. With modern microsurgical techniques of stitch-less cataract surgery (phacoemulsification and MICS) it is not necessary to wait for the cataract to mature.

 

What does cataract surgery entail?
It is one of the oldest, safest and most successful forms of surgery. It requires a very short hospital stay and is generally performed under local or topical anesthesia. The patient is awake during surgery but does not feel any discomfort or pain. Patients are ambulatory immediately after surgery and are discharged on the same day.

Step 1 :The eye operation is performed with the help of a sophisticated operating microscope. A small incision of 2.0-2.5 mm is first made in the eyeball

Step 2 :A smooth round opening is then made in the front part of the lens capsule, which is a thin membrane enclosing the entire lens.

Step 3 :All cloudy lens material within the lens capsule is then removed through the same incision by the procedure of phacoemulsification using a thin titanium probe that emits high-speed ultrasound waves, vibrating at 40,000 times per second. This breaks the cataract into tiny pieces, which are then suctioned out of the eye through the same probe.

Step 4 :In the final step, a Foldable Intraocular Lens (IOL) is introduced through the small incision, and placed within the capsule of the lens where it unfolds and stays in place securely.
One of the most recent advancements has been the ability to perform cataract surgery through even smaller incisions (as small as 1.8 mm). Small and micro incisions such as those used in phacoemulsification seal themselves immediately after surgery and heal very quickly. Compared to non-phaco cataract surgery, the postoperative rehabilitation for stitch-less phacoemulsification is faster and one can return to normal work and activities within a few days. This is currently the most effective method for removing cataracts.

 

Are there any problems with an Intraocular Lens (IOL)?
Fortunately, the technological advances in IOL manufacture and surgery have made it quite safe. Complications are rare and similar ones can occur with conventional surgery without an IOL implantation. All patients irrespective of other general illnesses like diabetes, hypertension etc. can have IOL surgery. If there is any reason why you should not have an IOL your ophthalmologist will explain.

 

Does one need glasses after IOL surgery?

The improvement in quality of life after cataract surgery is extraordinary, and most patients are not dependent on their distance glasses for daily activities. Some patients however, may need glasses of small plus or minus power to obtain the best possible distance vision.

 

IOL power calculations are done by trained personnel using a computerized ultrasound biometer for measuring the eye before the operation, and every endeavor is made so as to get very minimal post-operative power in the distance glasses. However, since these calculations are based on certain theoretical formulae, it will vary on a person-to-person basis, and some people may have a slightly larger postoperative refraction than others. Unlike the natural human lens, which can change its shape to focus for various distances, the IOL, since it is made of plastic, cannot do so. Hence, majority of patients undergoing routine phacoemulsification with IOL implantation, typically require reading glasses after cataract surgery.

 

What are the latest advances in Intraocular Lens (IOL) technology?

Advances in IOL technology have made available various state-of-the-art IOLs. These new lens designs include

  • Blue-light blocking IOLs that filter out harmful ultraviolet radiation as well as blue light,
  • Aberration-free IOLs which greatly improves image quality by enhancing contrast, eliminating glare and haloes, and improving night vision, and
  • The newer Multifocal IOLs which provides good unaided distance and near vision with less dependence on glasses.
  • Toric IOLs are also available for the correction of high cylindrical spectacle numbers.
  • MIL (Micro Incision Lens) can be inserted through incision  smaller then 2mm.
  • Recently Accomodative IOL’s have been introduced which have the property to change the focusing power for near work and provides good unaided vision for all distances. Depending on the patients' personal visual needs, the surgeon decides the most appropriate lens to implant in the eye.

 

Can all patients having a cataract undergo Phaco surgery?
Your eye surgeon will be the best judge to decide whether you can undergo phaco-surgery. Each patient undergoing cataract surgery is examined in detail to assess the health of the cornea. With the availability of newer technologies almost all the patients with cataract can be operated with phacoemullsification. But there may be situations where phacoemulsification may not be advisable such as poor endothelial counts, subluxated cataracts, poor view for surgeon as in corneal scars.

 

Is clear vision guaranteed after surgery?

  • No surgeon in the world can perform a surgery with guaranteed results. However, almost all the patients regain good vision following cataract surgery.
  • The calibre of vision obtained after a successful cataract surgery with IOL depends upon the health of the retina behind. Eye disease or problems in the cornea, retina or optic nerve may limit the potential for clear vision even when the cataract surgery itself has been successful.
  • However, it might not be possible to evaluate the condition of the retina, optic nerve, in advanced cataracts.
  • Cataract and IOL surgery is not a magical procedure and need not necessarily restore normal vision immediately. Blurred vision may be present immediately after surgery. As the eye heals over a period of time, vision improves gradually.

 

What are the possible complications that can occur with Cataract & IOL surgery?
Modern microsurgical techniques for cataract removal are highly successful procedures. The few complications that exist are becoming even more remote, with newer developments in surgical techniques and anesthesia.


Some minor complications that can occur include a slight drooping of the eyelid, swelling around the eye, corneal haze, reflections or slight distortion from the lens implant, which are usually temporary. The chances for serious complications are negligible. Possible serious complications include infection, severe inflammation, and hemorrhage. In a majority of cases these complications can be treated successfully or may resolve on their own with a good final restoration of vision. The above list is however not exhaustive.

 

Can Cataract be treated with Lasers?

Contrary to a popular myth cataract cannot be removed with lasers. Surgery done by phacoemulsification is commonly termed "Laser Surgery" by many people.


However, in a certain number of patients undergoing cataract surgery, the back part of the lens capsule may become thick or opaque over a period of time causing blurred vision.


This is known as a secondary cataract. This is not a complication. The condition is treated with a "YAG Laser Capsulotomy" with full restoration of vision.

 

Benefits of cataract surgery:
There are numerous benefits of cataract surgery, many of which cannot be measured statistically. These include: -
Improved colour vision - colours are brighter and more vivid after cataract surgery.

  • Greater clarity of vision - vision is crisper and sharper after cataract surgery.
  • Improved quality of life - studies have repeatedly shown that people enjoy an improved quality of life after successful cataract surgery. Many people can resume driving, reading, writing, watching television, sewing, household work and using a computer immediately after. Even when retinal diseases or other problems prevent a total restoration of vision, the remaining vision is usually improved by cataract surgery.