What are cataracts?
A cataract is the clouding of the eye’s inner lens, thereby not allowing the light to pass through it, causing initially diminution of the vision and later on blindness. They get worse over a period of time. The incidence of cataracts is higher in the elderly, but it has been seen in young people too.
How vision is impaired due to cataract?
The light passing through the lens and falling on the retina forms vision. The normal eye shows this function. A clear lens forms a good image, but a clouded lens is unable to pass light properly, which results in loss of vision. Patients with cataracts face such problems.
Symptoms of cataract?
Blurred vision: In cataract, there is blurring of distant vision and the patients face difficulty in driving in low light during the night time.
Glare: Cataract makes it difficult to see in bright light or even in sunlight. The normal in-house lights also seem very bright.
Double Vision: Two image formations when looking with one eye is confirmatory of cataract.
Color Changes: This disease affects color differentiation. Gradually a person is unable to distinguish between blues and purples.
Second Sight: Is a phenomenon when the lens becomes so able that it improves the ability to view near distant objects. This temporarily relieves the need for spectacles (reading glasses), but gradually over time, this worsens and this improvement in near vision deteriorates.
Frequent glasses change: Due to this disease, the vision deteriorates gradually requiring frequent spectacle change.
What are the causes of cataracts?
The precise mechanism of the formation of cataracts is still not clear. One of the risk factors is age, others include:
- Alcohol abuse
- Diabetes mellitus
- Eye injury
- Prolonged corticosteroids use
- Extended radiation or sun exposure
Diagnosis of cataracts is done by performing a vision test and a slit-lamp examination. After pupil dilation, the retina is also examined.
Initially the surgeon may prescribe new spectacles with changed numbers, use of glasses which does not allow glare to fall on the eyes, and use of tinted lenses. Surgeons may prescribe other things also.
Surgery is the last resort when all conservative measures fail. When the vision loss is so much that the person is unable to perform daily work, then surgery opts.
Three common methods of cataract removal
The most frequently done procedure is phacoemulsification. A surgeon uses a high-speed ultrasonic vibrating device to soften and break the cataract into multiple small size pieces. And sipping of these pieces is done. Post this procedure, the surgeon inserts an artificial lens into the eye. Sometimes the incision made is so small that no sutures are required, else only one stitch is put.
2. Extracapsular Cataract Surgery:
This is somewhat similar to earlier mentioned phacoemulsification. The difference is in the size of the incision, which is longer, as the central part of the lens is to be removed as a single piece. The remaining ports are left behind. Disadvantages include more sutures, healing time is more, and sometimes induces astigmatism.
3. Intracapsular Cataract Surgery:
Mostly done in difficult and advances cases of cataracts. A large incision helps in removing the complete lens and capsule.
Preparation before surgery
The patient has to come nil by mouth (for at least 8 hours prior to surgery). Before a few weeks prior to the planned surgery date, eye drops are prescribed. If already on some medications, how those medications are to be taken is advised.
What happens during the process?
Local or topical anesthesia used in this procedure. Anesthesia helps in alleviating pain and also paralyzes eye movements, which helps the surgeon in doing the surgery well. And then the phacoemulsification procedure as explained earlier is done. This surgery normally takes 15 minutes to 1 hour depending on many factors.
The patient remains in the recovery room for few hours before sending home. This surgery comes under day-care surgeries. The patients visit the hospital after 24 hours of surgery. Analgesics help in pain control.