When is cataract surgery recommended?
Once a cataract develops it cannot be cured by eye drops or medication. Patients with mild cataracts may be helped by using strong bifocal glasses and using appropriate light while reading.
Surgery is the only treatment for cataract and is recommended based on the severity of the disease and the impact on the daily activities of the patient. Patients usually make the decision to have surgery when the symptoms negatively impact their lifestyle.
Surgery is performed on one eye at a time with usually a one week gap between the operations. Cataract surgery is done on an outpatient basis where the patient can go home the same day. The area around your eye is numbed by local or topical anaesthesia depending on the doctor's decision and patient’s comfort. The cloudy lens is removed and replaced with a clear acrylic lens in the same lens capsule as the natural lens.
There are four types of surgical procedures to treat cataract:
The most common procedure used is Phacoemulsification where your surgeon uses an ultrasound probe to break up the lens which is then removed by suction. The advantage is that the incision is very small, around 1.8 to 2.8 mm, depending on the choice of lens, foldable or non-foldable. The incision heals on its own and does not require any eye patch or stitches. This surgery takes less than 30 minutes.
The second type of surgery is extra-capsular cataract surgery. This is performed when the lens is too dense and cannot be removed by phacoemulsification. The incision is larger as the complete lens is removed as a single piece. The healing process for this type of surgery is longer and requires an eye patch temporarily over the eye after the surgery.
The third type of surgery is called small-incision cataract surgery or SICS. This is performed by making an incision of 6-7 mm in the form of a tunnel through the sclera and cornea. The lens is removed and replaced with a rigid lens implant through this tunnel. No sutures are required, the tiny incision heals naturally itself.
Laser technology has evolved in cataract surgery and is the fourth type of surgery called Femtosecond-assisted laser cataract surgery. This surgery involves accurately focusing a high-speed laser beam on the corneal tissue to incise it and remove the cataract. Your surgeon can perform various parts of the procedure with this laser technique including making corneal incisions, circular symmetrical opening in the lens capsule and breaking the lens easily into fragments by softening it.
Advantages of this laser technology include accurate intraocular lens positioning, precise corneal incisions, reduced ultrasound energy and gentle removal of the softened cataract through phacoemulsification. It also corrects a type of refractive error called astigmatism.
Various types of intra ocular lenses are used during cataract surgery. These include:
Monofocal lens: this type of lens does not provide correction for near sightedness or astigmatism and corrects vision for only one distance- either far, intermittent or near. As a result, the patient will require glasses or contact lenses after the surgery for the best possible vision.
Multifocal lens provides correction for both distance vision and near vision simultaneously but does not correct astigmatism. The disadvantage however is it can cause more glare than the monofocal lens.
Premium intraocular multifocal lens, also called toric lens, provides correction for astigmatism as well as distance and near vision. The advantage of a toric lens is the patient usually does not require glasses or contact lenses for normal vision after the surgery.
Accommodative lens are very flexible and mimic the movements of the natural eye lens by changing its shape inside the eye. This allows the eye lens to easily accommodate the change in focus for close and distant objects.
Post-operative care for cataract surgery
Following surgery, your doctor will prescribe eye drops to prevent infection and inflammation. A follow up visit is scheduled to monitor healing and to check for any complications from surgery. Once complete healing occurs glasses are ordered for optimal vision, as required. This will depend on the type of intraocular lens inserted in the eye by your surgeon.