A cataract is a condition that involves vision loss as result of clouding of the natural lens in the eye. It can occur in either eye or both. The lens is the region in the eye that receives light waves and focuses them on the retina. The retina layer at the back of eye then processes these light waves to form an image. With cataracts, there is an abnormal accumulation of protein in the lens, which reduces and distorts the amount of light passed on to the retina.
The majority of cataracts is due to aging and can start to form by the age of 40, although the loss of vision normally affects quality of life by the age of 60. Others may be due to underlying diseases such as diabetes, trauma to the eye, exposure to radiation, while some people are born with them.
How Are Cataracts Diagnosed?
Patients will normally complain of the following symptoms:
- Blurring of vision
- Colors seem faded
- Glare with lights
- Double vision
- Poor night vision
- Frequent prescription changes in their eyeglasses
These symptoms may be caused by a variety of eye conditions. If a cataract is not dense enough to be easily seen on initial inspection, these symptoms will prompt a doctor to do a formal eye examination. A visual acuity test, normally involving reading letters from a chart hanging on a wall, will measure how well a patient can see at a distance. The doctor will also check how well you see things that are at the center of focus and how well you see things that are off to the sides Medication drops to dilate the pupil will enable the doctor to see the patient’s retina and assess for any optic nerve damage. A tonometry test will also be done to measure the pressure inside the eyeball using a special device to rule out glaucoma.
How Are Cataracts Treated?
The main treatment for cataracts involves surgery to remove the cloudy lens and replace it with a new man-made one. Not everyone needs treatment. Surgery is considered when the cataract disrupts daily living or if it prevents access to another condition at the back of eye that needs treatment. There are two main types of surgery: phacoemulsification and extracapsular surgery.
In phacoemulsification, or phaco for short, the ophthalmic surgeon makes a small incision and inserts a probe. This probe emits ultrasound waves that are able to soften the proteins making the lens blurry. These softened proteins are then suctioned away. In extracapsular surgery, a longer wound is required to remove the whole lens in one piece. In both operations, the natural lens is replaced with an artificial plastic one known as an intraocular lens. There are 3 main types of intraocular lenses. The conventional lens produces a limited range of focus. The multifocal lens produces clear near and distance vision. Finally, a special toric lens is available for patients with an underlying condition called astigmatism, where the eyeball is football-shaped rather than round.
Although cataract operations are now considered to be mainstream and widely available, all surgical operations, no matter how straightforward, carry potential risks. The procedure and complications should be discussed before embarking on the operation. Some complications of cataract surgery include:
- Increase in the risk of retinal detachment – this presents as the sudden appearance of black specks floating in the patient’s field of vision
Surgery cannot be performed on both eyes at the same setting. The operation itself normally lasts about one hour and is painless. Some patients choose to be awake during the operation.
Recovery After Cataract Surgery
The patient will need to arrange someone to drive them home on the day of the operation and help them around the house for a few days afterward. An eye patch is normally worn after the operation for a few days as well. It is normal that the eye feels a bit itchy and is sensitive to light. The patient will be discharged with medication to help with this. In most cases, vision is much clearer by the next day although healing is complete by 8 weeks. At this time, the operation for the second eye cataract may be scheduled if needed. In general, the patient will be advised to take a few days off from work to recover completely, not operate heavy machinery and not drive until vision is completely restored. Swimming and eye make up should be avoided for at least one week.
Because cataracts are not a life threatening condition and only progress slowly, surgery for cataracts is not seen as an absolutely necessary measure. The decision to have surgery should take into account how badly the cataract is affecting the quality of life of the patient and whether they have needed to stop doing certain things because of it.
How Can Cataracts Be Prevented?
- Stopping cigarette smoking
- Getting regular eye examinations to catch the formation of cataracts early