About
A cataract is a condition where the eye’s natural lens becomes cloudy, hindering the transmission of light rays to the retina, leading to blurred, hazy vision or, in severe instances, loss of sight. Cataracts can make everyday activities like reading, driving, or seeing faces dull or less colourful.
Cataracts usually form slowly, and people experience a gradual blurring of vision
Causes
Age is the most common cause of cataracts and most people will develop cataracts as they grow older. Other causes of cataracts or the development of cataracts at an earlier age include medical conditions like diabetes, certain medications like corticosteroids, high myopia, previous eye surgery, trauma etc.
Conditions associated
- Diabetes mellitus
- Previous eye surgery
- Previous trauma to the eye
- Familial cataract
Symptoms
Symptoms for cataracts include blurring of vision, difficulty in contrast, especially shades of colours, frequent change in the glasses prescription, glare or light scatter
Examination/Diagnosis
The diagnosis of cataracts is made after examination by the ophthalmologist on the slit lamp in the clinic. The patient may need dilating drops to open the pupil and examine the lens thoroughly. Additional testing of the retina may also be needed, as well as refraction for glasses.
Investigation
Once the diagnosis is made, the patient may be asked to have tests to examine the cornea ( pentacam) , to determine the strength of the replacement lens ( biometry) and a retina scan to look for retinal conditions as well ( OCT)
Treatment
Cataracts do not currently have any medical treatment options available, such as drops or medications. Surgery is usually the recommended treatment for this option.
However, cataract surgery is a highly successful, straightforward procedure that typically takes between 20-30 minutes and is most often performed under local anaesthesia. Sedation or general anaesthesia may be used in certain situations.
During cataract surgery, the natural clouded lens is replaced with an artificial lens called an intraocular lens (IOL). An IOL can restore vision lost to cataracts and correct refractive errors such as nearsightedness (myopia), farsightedness (hyperopia), astigmatism or presbyopia. Multiple options for the lens are available, and your doctor will advise you on which is best suited to your individual needs.
The different types of lenses are:
- Monofocal lenses: These lenses provide clear vision at a single set distance, typically far away. Patients might still need glasses for near activities like reading or intermediate distances, such as using a computer.
- Multifocal Lenses: These are designed to provide clear vision at multiple distances. They are divided into sections, each focusing light from a specific range (near, intermediate, far).
- Extended Depth-of-Focus (EDOF) IOLs: These lenses provide a continuous range of high-quality vision for far, intermediate distances, reducing the need for glasses.
- Accommodative lenses mimic the eye’s natural ability to change focus (accommodation). They move or change shape inside the eye, providing a range of clear vision.
- Toric lenses: Toric lenses are specifically designed for individuals with astigmatism. These lenses are shaped to correct astigmatism and provide clear distance vision. Toric lenses come as monofocal, multifocal and EDoF as well.
