Cataract seen in the old age may be caused by normal aging process but seen at younger age is caused by many disease processes e.g. some eye diseases like uveitis, general diseases like diabetes, heredity, injury, radiation, infections and many more.

The most important symptom of cataract is a decrease in vision for distance & /or near objects. Other features are decreased vision in bright or low light, decreased contrast, altered color appreciation, seeing many images of one object, rapid changes in the number / power of glasses, or sometimes pain, redness and watering. In advanced cases there is complete loss of vision and pupil becomes pearly white in color. However, none of these symptoms are seen exclusively in cataract.

The first thing a person must do on experiencing any of these symptoms is to consult an Eye Surgeon (Ophthalmologist) for thorough eye examination. Answers to the following questions should be sought:

• Do I have cataract?

• Do I have any other eye disease?

• What is the cause of cataract in my eye?

• What are the treatment modalities available?

• What treatment would be most suitable for me?

• What is the expected outcome of the surgery in my case?

• What are the risks involved and possible complications?

• How long can I wait before I get operated?

• What does the surgery involve in terms of time and expenditure?

• What are the different techniques available & their merits?

• What are the different types of lenses available & the merits of each?

In Phacoemulsification a very small incision (3 mm or less) is made into the clear part of the eye (Cornea) and the hard core (nucleus) of the lens is converted in to a soft pulp using high frequency sound waves (NOT Laser) and sucked out. Then a foldable lens (IOL) is injected through the small incision and positioned into capsular bag. The main advantages of this operation are early rehabilitation and decreased occurrence of astigmatism (cylindrical power in glasses) & other complications. Non-foldable IOLs are not recommended as they necessitate enlarging the incision and thereby sacrificing the advantages of the small incision.

All these operations are done under topical anesthesia (or eye drop anesthesia) which makes the eye numb/senseless, and the patient although conscious does not feel any pain. Rarely does one need to use injection anesthesia. The general anesthesia , which has its own risks, is used only in children and uncooperative patients. Topical or eye drops anesthesia is the preferred method as not only the painful injections and the eye bandage are avoided but it also reduces the risk associated with injection anesthesia (e.g., retro-bulbar hemorrhage, globe perforations, etc.)

MICS (Micro Incision Cataract Surgery) is just a variation of Phacoemulsification. Here using thinner phacoemulsification tips, the surgery is performed through narrower incision (about 2 mm). It offers only minimal advantage over standard phacoemulsification by causing slightly lesser surgical iduced astigmatism. However, the IOLs implanted through such small incisions are still very new and the experience with them is very limited.

Intra-ocular Lenses (IOL) are small (about 6 mm) lenses made of a soft polymer (Acrylic) and are implanted inside the eye in place of natural lens. The greatest advantage of IOL is a clear wide field of vision and the fact that the patient does not have to constantly wear thick glasses. However, glasses with low power may be still be required especially for reading distant and near small print. The reason being that unlike natural lens the IOL has a fixed power (estimated by doing Ultrasound of the eye) which is usually adjusted such that the mid-range or routine viewing distances are seen clearly, and for distances closer or further low powered glasses may still be needed. Since the IOL stays in the eye lifelong therefore there should not be any compromise on the quality of the IOL. Multifocal IOLs offer the advantage clear distant and near vision and, thus, lesser dependence on glasses but suffer the disadvantage of lower contrast, lower color saturation and a subjective compromise in image quality. Alcon Restor IOL gives good results for near and distance vision. But both eyes have to be operated within short interval of 2-6 weeks and it take about 4-8 weeks for complete adaptation to new visual status.

SICS (Small Incision Cataract Surgery) has virtually replaced the conventional cataract surgery for difficult situations. Here although the incision made is larger (5-6 mm) and the nucleus is removed using fluid pressure, yet no stitches are required and the recovery is much faster and more comfortable than the conventional surgery.

To conclude, the surgeon, the surgical technique and the quality of the IOL are not the only factors that decide the result of cataract surgery; but also the condition of the eye otherwise, the cornea, the retina and the presence of systemic diseases like diabetes, hypertension, asthma, infections, etc. Moreover, the quality of the operation theatres, the ancillary and the backup facilities, the training of the support staff, etc. also have a significant influence on the success of the surgery. Ensuring good quality in all these areas leads to increase in the surgical cost for the patient, but it must be understood that our eyes are worth a lot more...

Click here to read a detailed medical article on Cataract.

What is the lens of the eye?

The most common symptoms of a cataract are:

• Cloudy or blurry vision.

• Problems with light, such as headlights that seem too bright at night, glare from lamps or the sun, or a halo or haze around lights.

• Colors seem faded

• Double or multiple vision (this symptom goes away as the cataract grows).

• Frequent changes in power of spectacles or contact lenses.

These symptoms can also be a sign of other eye problems. In the event of any of these symptoms please consult an eye surgeon.
In early cataract one may not notice any changes in vision. Cataracts tend to grow slowly, so vision gradually worsens. Some people with a cataract find that their near vision suddenly improves (phenomenon of second-sight), but this is temporary. Vision is likely to get worse again as the cataract grows.

• Age-related cataract: Most cataracts are related to aging.
• Congenital cataract: Some babies are born with cataracts or develop them in childhood, often in both eyes. These cataracts may not affect vision. If they do, they may need to be removed.
• Secondary cataract: Cataracts are more likely to develop in people who have certain other health problems, such as diabetes. Also, cataracts are sometimes linked to steroid use.
• Traumatic cataract: Cataracts can develop soon after an eye injury, or years later.

How is a cataract diagnosed?

A comprehensive eye examination usually includes:

• Visual acuity test: This eye chart test measures how well you see at various distances.

• Pupil dilation: The pupil is widened with eye-drops to allow us to see more of the retina and look for other eye problems.

• Tonometry: This is a standard test to measure eye pressure. Increased pressure may cause glaucoma.

• Ultrasound (Biometry) of the eye to calculate the power of the lens to be implanted.

Other eye and general test may be required to establish complete diagnosis and fitness for cataract surgery.

 Cataract Surgery

The lens is enclosed in a capsule, an outer covering that holds it in place. There are many different techniques for cataract surgery, but all fall into one of two basic categories:

• Phacoemulsification: The front of the capsule is opened and the cataract is removed, leaving the back of the capsule in place. Sound waves (ultrasound) may be used to soften and break up the cloudy lens so that it can be removed through a small cut. This is called phacoemulsification. Currently phacoemulsification with a foldable intraocular lens implantation through a 3 mm incision is the most preferred method of cataract surgery and has the best results, all over the world. In MICS or Micro-Phaco the incision size is about 2 mm.

• Other types of operations are performed in special circumstances.

Currently, lasers are not used to remove cataract (although some patients mistakenly use the term Laser for Phacoemulsification). Although research is under way to use lasers in cataract surgery and some success has been reported with use of "Dodick Laser" in the treatment of soft cataracts.

What are the preventive measures?