What is Cataract?
Cataract is a condition which partially or completely reduces the transparency of the lens in your eye, ultimately making you unable to read and to see the world around you. In cataract, your lens turns white in color and becomes opaque, from being previously color less and transparent. This can happen in one eye or both, though not necessarily at the same time.
Who gets Cataract?
Cataracts form as you grow old. Cataracts occur in people above the age of 50 and more often in people older than 60 years. Apart from age, cataract can also occur due to injury; or due to family history. You may also develop cataract if you are on long-term medications like steroids (including inhaled formulations) as well as certain medications for treatment of hypertension.
What are the indicators of cataract?
When you have a developing cataract, you will find it difficult to look at bright light which will dazzle, making it difficult to see. This effect is called Glare. You could also see “halo’s” around lights, or you may also have blurred vision.
Following are the common indicators of the presence of cataract though, not all may occur together.
- Clouded, blurred or dim vision
- Increasing difficulty with vision at night
- Sensitivity to light and glare
- Seeing “halos” around lights
- Frequent changes in spectacles or contact lens prescription
- Fading or yellowing of colors
- Double vision in a single eye
How is Cataract treated?
Surgery is not always the first recommendation. If detected early, the doctor may prescribe spectacles or contact lens to improve your vision. As long as cataract doesn’t interfere with your everyday activities, you may not need surgery. But, if cataract has spread in the lens, enough to seriously impact your sight and your daily routine, the doctor may consider cataract surgery. If you have cataract in both eyes, the doctor will treat one eye first, and then the second eye several days Iater. This allows time for the first eye to heal.
What is cataract Surgery?
To understand what happens in cataract surgery, let’s look at the lens itself and how it is constructed. The human eye lens is made of protein fibers and water, with the fibers arranged in a pattern that allows light to pass through. In the normal eye the lens is clear and transparent. The lens has 3 layers – an outer Capsule which is like a “tough shell”, wrapped around the lens. Just under the Capsule is the soft lens Cortex, which contains cells that are active and continue to grow and divide. The Cortex covers the inner core or the Nucleus. This core becomes denser and harder as a person ages.
What kind of surgery choices cam a cataract patient have?
There are three cataract surgery procedures:
lntracapsular cataract extraction (ICCE), Extracapular cataract extraction (ECCE) and Phacoemulsification (Phaco). ICCE is an outdated procedure and is no longer used, or performed very rarely.
What is ECCE?
ECCE is also an old technique. In ECCE, the only the cataract-affected lens is removed, without removing the parts that hold the lens in place. After ECCE, you may have to use spectacles to further correct your eyes for sharper vision. Cataract surgeons in India have pioneered another technique called Small Incision Cataract Surgery (SICS). The benefits of SICS are, considerably shortened surgical time, quicker recovery, fewer post-operative complications and finally, lower cost than Phacoemulsification. Ask your doctor about SICS.
What is Phacoemulsification (Cataract surgery explained):
Most surgeons today prefer Phacoemulsification in cataract surgery. It is quick, the wound usually heals without getting infected and the patient is able to resume normal activity very soon. During surgery for cataract extraction, the surgeon cuts a round hole through the anterior (i.e. front) side of the capsule to remove the cortex and nucleus and place an IOL into the remaining capsular bag. During surgery, the opaque, white lens is removed and replaced with a synthetic mono-focal or multi-focal lens. The monofocal lens will offer either better short distance or better long distance vision; the multifocal lens offers both short distance and long distance vision, without the aid of spectacles. Some users of multifocal lenses may report seeing halos i.e. a circular band of colored light around a light source. They may also report reduced ability to see the difference between the object and its background.
Are there different types of intraocular lenses?
Yes. There are several types and each type has a specific use. You should consult your doctor and ask about the best choice for you. The doctor will consider your age and health, your profession and your financial circumstances and recommend the lens that suits you best.
A Brief description of the four major types is given below:
- Monofocal: Monofocal lens is meant for viewing objects which are either near, at an intermediate distance or further away. A commonly used lens in cataract surgery, two varying monofocal lenses can be inserted in each eye, so that far vision is possible with one eye and near vision with the other.
- Toric: A Toric intraocular lens is implanted after phacoemulsification surgery. It is not a multifocal lens. This lens is specially designed to correct astigmatism (lack of sharp focus). Astigmatism can occur due to an irregularity in the natural lens or in the ‘cornea (the clear, transparent front of the eye). So light passing through the cornea and lens at different positions have different focal points, which can lead to blurry vision at all distances. Astigmatism can be corrected with glasses or contact lenses, and some degree of corneal astigmatism can be corrected with LASIK.
- Multifocal lens: Multifocal lens has different regions with different power to be able to view objects which are near, at an intermediate distance and further away.
- Accommodating lens: The latest in cataract management, an accommodating lens – like multifocal lens – allows viewing objects which are near, at an intermediate distance and far away. This lens uses the muscles in the eye to bend – like the natural lens. This bending changes the shape of the lens within the eye and allows you to see better. This lens offers both distance and near vision capability because it functions like a natural lens. This is made possible by use of two small hinges, which allow the lens to move forward and backward in the eye. Therefore, the lens can change its power in the eye, similar to the process of accommodation of the eye’s natural lens. Hence, it is called an accommodating lens, i.e. one that can provide both near and distance focus. An accommodating lens comes as close to your natural lens as technology permits.