The crystalline lens of the eye is clear and transparent. In certain circumstances, it develops cloudiness or opacity. This obstructs light from being transmitted to the retina causing blurring of vision. This conditions is known as a cataract.
One of the most common causes of cataracts is increasing age which causes the lens to harden and turn cloudy. Other less common causes of development of cataract are -
- In rare cases, children are born with the condition.
Some of the symptoms of a foreseeable cataract include –
- Blurred vision
- Double vision
- Image distortion
- Sensitivity to glare
- The need to change glasses frequently
There is no scientifically proven medicine that can reduce or dissolve cataracts. Surgical removal is the only option.
One should consider surgery as soon as the cataract starts interfering with the patient’s lifestyle. You should ideally seek a seasoned ophthalmologist’s opinion before considering 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: The entire cataract is removed from the lens of the eye. This technique is now redundant and obsolete.
- 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 a large incision and stitches, which are removed after a short interval
- Phacoemulsification: This technique removes the cataract through a small 2 mm incision in the eye. The cataract in the lens is broken into fragments and each of these is then liquefied (emulsified) using ultrasound energy. This technique usually takes 5-7 minutes, depending upon the density of the cataract. After the surgery, foldable intraocular lenses (IOL) are inserted through these small incisions. Phacoemulsification is the most popular cataract surgery these days. It doesn’t require stitches, patches or injections.
The surgery takes very little time and patients need to wear black/dark glasses for a day or two. These lenses are usually permanent and don’t need to be changed and are of different types:
- Mono-focal: Routinely used for most cases, generally corrects the distance vision, a small number is left for near vision( Reading, Computer etc).
- Multifocal: 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.
- Multifocal Toric IOL: This is recent available technology which corrects the cylindrical power and reduces the dependency on glasses for both distance and near vision.
Cataract surgeries have a very high success rate (over 99%). It is however important to realize that factors such as the condition of the retina, optic nerve, pre-existing disease, amblyopia (lazy eye), etc play a very important role in the visual recovery after cataract surgery. Sometimes it may be difficult to diagnose the abnormality before the surgery because of the dense cataract.
In most cataract surgeries (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. Since it is a part of the lens, it may become opaque and hamper vision even after cataract surgery. This condition is called posterior capsular opacification (colloquially known as ‘chari’). It may develop within a few months to few years from surgery, though its incidence is significantly reduced with foldable lenses. Chari is treated as an OPD procedure by a laser that takes about 1-2 minutes only.
If left untreated, the condition usually worsens (becomes more cloudy). This leads to rapid deterioration of vision and erratic changes in glasses’ numbers. If a cataract is left untreated in the long run, it can cause glaucoma, intraocular inflammation and in some conditions the lens may even move from its original position. These complications may cause permanent damage and affect the final visual recovery even after surgery, and also make the surgery technically more difficult.
The technique is such that a person can resume their normal lifestyle very soon. One can start reading after a day or two. While office work shouldn’t prove troublesome, one should avoid dusty environments or work that can cause physical strain. One should also avoid exercising and other sort of workouts for four to six weeks. Swimming should be avoided for two months at least.