A cataract is a clouding of the lens of the eye. In a young person, the lens is crystal clear and allows light to pass through and focus on the retina. As the lens ages, the lens nucleus becomes opaque, or opacities form in the lens cortex that block or scatter light resulting in diminision of vision.
While there are no known causes, studies have identified a number of risk factors:
- Age – Cataracts are a normal part of aging. Occurs as a result of natural aging process of lens, which become opaque over a period of time.
- Excessive exposure to sunlight.
- Traumatic Cataract – Develops as a result of any injury to the eye.
- Metabolic Cataract – Develops as a result of defect in the body metabolism such as:
High cholesterol / triglycerides
- Toxic Cataract – Certain toxic substances or drugs can lead to cataract if taken over a period of time. Eg.: Cortisone medication, Chlorpromazine, etc.
- Secondary Cataract – Some other primary eye disease such as chronic inflammation or glaucoma can lead to forming of cataract
- Painless blurring or dimming of your vision
- Sensitivity to light and glare, especially in bright sunlight or while driving at night.one may also experience poor depth perception.
- Increased nearsightedness, requiring frequent changes in your eyeglass prescription. As cataract develops,changing glasses would no longer help improve vision.
- Distortion or ghost images in either eye.
Currently, there is no proven way to prevent cataract or the development of cataracts other than controlling medical conditions that may be the cause. Antioxidants like beta carotene and vitamins C and E have been identified as reducing the risk of developing cataracts and slowing their progression.
We can diagnose the presence of a cataract through a routine eye examination. However, once a cataract is detected, we will monitor its progression. The eye examination evaluates:
- Visual Acuity – Check vision in both eyes unaided and with best possible corrective glasses and pinhole vision is checked to know the improvement and get the general idea about macular function of the eye. This will help in prognostic evaluation of post operative visual recovery.
- Intra Ocular Pressure – To rule out rise in pressure secondary to cataract. If raised, surgery is needed to prevent further complications.
- Slit lamp Examination – To know the type of cataract and its progress and any associated eye disease.
- Direct And Indirect Ophthalmoscopy – To examine the posterior segment of the eye like vitreous and retina.
- A-scan Biometry – Calculate the Axial Length and Intra Ocular Lens Power for implantation.
There is presently no medical treatment that prevent cataract or reverse them once they develop. The only treatment for cataract is surgery. Though in initial stages of cataract glasses may help to improve vision. The decision to operate is taken by the patient and the doctor together, depending on how cataract is affecting patient’s lifestyle. With the recent advances in cataract surgery, one does not require to wait till vision drops to finger counting. The sooner the operation is done, the better are the results.
Cataract surgery is almost always an outpatient procedure, done under local anesthesia. During surgery, the lens is removed and replaced with an artificial one (implant) that performs the same function.
Two types of surgical procedures are commonly performed: Extracapsular extraction and phacoemulsification. The extracapsular method has been the standard for over a decade, but with advancing technology in surgical equipment and Intra Ocular lens implants for both methods, phacoemulsification has gradually become the procedure of choice in the majority of cases.
- Incision of about 7-8 mm is made.
- Lens nucleus removed from capsular bag in one piece.
- Cortical material removed by aspiration (suction).
- Intra Ocular lens placed in the capsular bag where natural lens was there.
- Eye sutured with seven to nine nylon stitches.
- Postoperative astigmatism due to stitches.
- Removal of some of the stitches after six or more weeks to reduce astigmatism.
- Corrective glasses after stitches are removed, or when astigmatism subsides (usually six to seven weeks after surgery).
- Small tunnel incision of 2-3mm near the cornea is made.
- Lens nucleus is broken into pieces and removed from capsular bag by ultrasonic emulsification and suction.
- Remaining Cortical material removed by aspiration.
- Intra Ocular lens placed in the capsular bag.
- No stitch or, in some cases, one stitch to close the small incision.
- Little or no astigmatism.
- No stitches to remove. If there’s one stitch, it remains there without any ill effect.
- Corrective glasses after the eye stabilizes, usually a few weeks after surgery.
Rapid Recovery, Patient can resume their routine almost the next day, Better visual results – little or no astigmatism.
- Take it easy for the first two or three days after the operation.
- Resume normal activities including moving around and bending down, but be careful because it’s hard to judge distances with one eye covered.
- Try not to touch or rub the eye.
- Keep soap and shampoo out of the eyes (it’s sensible to avoid washing your hair for the first few days).
- In the first few weeks after the operation, avoid heavy lifting as this can increase the pressure in the eye and could put a strain on the healing scar.
- If you suffer more than mild pain, or you experience loss of vision or increasing redness of the eye, you should contact the hospital for advice.
Cataract surgery is almost always an outpatient procedure, done under local anesthesia. A small incision is made in the eye, and the front surface of the cataract is opened to allow access to the clouded tissue inside. The cloudy portion is then removed, leaving the thin clear back surface of the lens in place This can be done either with a mechanical device called a phacoemulsifier or manually with extracapsular instruments. The lens implant is then placed in the shell of the natural lens, and the incision is closed.
This can be done either with a mechanical device called a phacoemulsifier or manually with extracapsular instruments. The lens implant is then placed in the shell of the natural lens, and the incision is closed.
Patients return home after surgery, and are usually examined the following day. Eyedrops are used to accelerate the healing process and prevent infection, and patients are instructed to avoid any activity that could harm the eye while recovering from surgery. Vision almost always improves greatly within 4-6 weeks, although many patients may see better within 1-2 weeks or less. Almost everyone will need a new glasses prescription after surgery, although it may be needed only for distance or for reading depending on the choice of lens implant power.