What is a Cataract?
A Cataract is the opacification of the once clear fibres in the crystalline lens of the eye. It is most commonly caused due to ageing, but may also occur due to other reasons like trauma or metabolic conditions like Diabetes Mellitus. Occasionally, children may be born with “Congenital” cataracts, which need detailed evaluation to establish the underlying cause, and are operated on depending on the extent of visual involvement.
When does it occur?
An age-related cataract may occur at any time after 40 years of age. There has been a gradual rise in the number of younger individuals being diagnosed with cataract. This can be attributed to increasing in UV exposure, better diagnostics and more awareness about cataracts.
When do I need to get it operated?
A cataract that hampers your daily activities and interferes with clear vision needs to be removed. Occasionally, early cataracts may not cause any disturbances in vision, in which case they may be observed and removed at a later date. A contrary opinion is that it may also be removed at the earliest, instead of waiting for it to inconvenience your lifestyle.
Which Lens is recommended?
Every cataract surgery is accompanied by implantation of an Intraocular Lens. This Lens power is calculated based on certain measurements of the individual’s eye prior to surgery. (This is different from the spectacle power of the eye.)
The traditional Lenses that have been implanted over the years are called “Monofocal” Intraocular Lenses which correct only one focal point, i.e.typically correct distance vision. This means that near work (reading/writing/mobile phone use/looking at your wristwatch) will require glasses.
Toric Multifocal Intraocular lens implanted in the eye during cataract surgery- the black arrow points to multiple concentric rings which make the lens Multifocal, and the green arrow points to the 3dots in which axis the cylindrical power of lens is put as per calculations
To overcome this disadvantage, Multifocal Intraocular Lenses can be opted for. They help in giving reasonably good vision for distance as well as near. However, they require a detailed evaluation and can only be implanted on the advice of your eye surgeon.
It is imperative to know, that these lenses help reduce but may not eliminate your need for reading glasses.
What is Astigmatism Correction?
Astigmatism or Toricity is a cylindrical power in an individual’s eye. Toric Intraocular Lenses are another type of specialized lenses to cater to a separate category of individuals who have high cylindrical power in the eye. This Toric Lens maybe advised because exclusive correction of spherical power (distance and/or near) may still cause distorted images and hence blurred vision for individuals who have toricity.