What is Cataract?
Cataract is clouding of the natural lens in the eye. We are (generally) born with a crystal clear lens that gradually darkens and hardens with age. The majority of cataracts are age related however can be brought on earlier by other types of eye surgery, some medications and some medical conditions as well as genetic predisposition.
What are the symptoms?
Cataract affects the quality of vision and depending on the degree and type of cataract can cause:
Blurring for distance and for reading
Glare symptoms such as difficulty with oncoming headlights when driving at night
General darkening of colours
How can it be treated?
There are two ways of dealing with cataract:
Attempt to mitigate the symptoms with aids for reading such as magnifiers and sunglasses to reduce glare however the only treatment option is:
This is a procedure where the cataract is removed and replaced with an artificial lens implant.
It is usually carried out as a day case procedure under local anaesthetic (although a small proportion of patients opt for sedation or a general anaesthetic) and takes twenty to thirty minutes on average.
There are different artifical lens implant options that are classified as:
Standard lens implants
This is a lens that has a fixed power (monofocal) where the power of the lens is based on your eye measurements and where you want the focus point to be.
Usually it is set for distance so that good distance vision is achieved without glasses although can be set for any distance such as for reading if so desired as is sometimes the case with shortsighted people who are used to reading without glasses although that would necessitate glasses for distance.
This is the most common type of lens implant as is generally considered to provide the best quality of vision albeit with the aid of glasses for some tasks.
Some people are able to achieve glasses independence for distance and near even with standard lens implants by adjusting one eye for distance and one for reading (monovision) however this is not suitable for everyone.
Premium lens implants
There are a variety of premium lens implants (so called as they are more expensive) including:
Toric monofocal lenses - These aim to correct astigmatism in the eye which is not addressed by a standard monofocal and are a good option where there is enough astigmatism that your vision would still be blurred with a standard monofocal lens.
Trifocal lens - Like multifocal or varifocal glasses these lenses use separate areas to focus light for near, intermediate and far. They are generally well tolerated however have a rate of side effects such as halos and glare.
Extended depth of focus (EDOF) lenses work in a similar way to give a larger range of focus to reduce dependence on glasses but in general do not provide as good magnification for reading as trifocal.
There are advantages and disadvantages to the different lens options which will be discussed in more detail at your consultation.