The human eye is constructed in much the same way as a camera, with the lens to focus the light onto the retina, which is the equivalent of the film. The retina then transmits the focused image to the brain via the optic nerve.
WHAT IS A CATARACT?
Cataract is cloudiness of the lens and it causes vision to deteriorate. Before this happens, it is common for the eye to become progressively short sighted so that frequent change of glasses becomes necessary.The eye is more sensitive to light and glare and you may see ghost images
WHAT ARE THE CAUSES OF CATARACT?
The commonest type of cataract is senile i.e. age related Other causes of cataract include
- Long term steroid use
- Injury to the eye
- Recurrent inflammation in the eye
- Diabetes can accelerate cataract formation
WHEN DO WE OPERATE?
When glasses can no longer help sufficiently and when the patient has significant problem with his/her vision while reading/driving/watching television, the only effective treatment is to remove the cataract and to replace it with a plastic lens The power of the lens to be implanted is assessed before the operation.
WHAT ARE THE TYPES OF SURGERY AVAILABLE?
Presently the commonly done procedure is the stitch less one-PHACOEMULSIFICATION Here the cut made is 2.5 mm and is self sealing. The cataract is broken into small pieces using ultrasound energy and sucked out. The artificial lens implant is then folded and inserted through the same small cut-it opens once inside and is rotated into its position
The advantages of phacoemulsification are that the wound is very small and heals quickly-thus recovery of vision is faster (1week on an average) and the restrictions after surgery are minimal. However it is not suitable for all types of cataract and the final decision as to the type of surgery best suited to your cataract should be taken after discussion with your doctor.
WHAT ARE THE TYPES OF LENS IMPLANTS AVAILABLE?
- Foldable lenses which can be inserted through a 2.5 mm incision. These can further be Uni focal Aspheric (designed to minimize aberrations) Multi focal(allows freedom from glasses but associated with some degree of glare and night vision difficulty-suitable for a small sub group of patients only)&Toric to correction any astigmatism which may otherwise need correction with spectacles inspite of lens implant
- PMMA lenses which are not foldable and have to be inserted through a minimum 5 mm incision.
CAN THERE BE COMPLICATIONS?
- As with any surgery there can be rare complications such as
- Bleeding within the eye/residual cataract fragments in the jelly of the eye
- Insufficient capsular support so the lens cannot be implantedIinflammation/swelling of the cornea
- Rise in eye pressure
- Retinal detachment
Most of these problems are correctable though it may need a second surgery sometimes.