Cataract

The lens of the eye is normally clear (transparent). It acts like the lens on a camera, focusing light as it passes to the back of the eye.Until a person is around age 45, the shape of the lens is able to change. This allows the lens to focus on an object, whether it is close or far away.As a person ages, proteins in the lens begin to break down. As a result, the lens becomes cloudy. What the eye sees may appear blurred. This condition is called cataract.

What are the symptoms you can have with cataract?

Cataract formation is painless. The common problems one may face are:

  • Blurry vision
  • Colors that seem faded
  • Glare - headlights, lamps or sunlight may seem too bright. You may also see a halo around lights.
  • Not being able to see well at night
  • Double vision
  • Frequent prescription changes in your eye wear

Causes of cataract

  • Age - Age is the most common cause. Lens proteins degrade over time and this process is accelerated by diseases such as diabetes and hypertension. With the passage of time, environmental factors including toxins, radiation and UV light have an accumulative effect.
  • Ultraviolet (UV) light – UV light specifically UV-B, has been shown to cause cataract and there is some evidence that sunglasses worn at an early age can slow its development in later life
  • Trauma- Blunt trauma causes swelling, thickening and whitening of the lens fibers. While the swelling normally resolves with time, the white color may remain. Penetrating injuries may directly puncture the lens and cause cloudiness of lens
  • Genetics- There is a strong genetic component in the development of cataract, most commonly through mechanisms that protect and maintain the lens. Children with specific genetic anomalies can have early catract as in Down syndrome, Patau syndrome, Turner’s syndrome
  • Smoking- Cigarette smoking has been shown to lead to a two-fold increase in the rate of nuclear sclerotic cataract and a three-fold increase in posterior subcapsular cataract.
  • Medications- Some drugs, such as corticosteroids, haloperidol and miotics may cause cataracts.
  • Skin diseases- The skin and the lens have the same embryological origin and can be affected by similar diseases. Those with Atopic dermatitis and Eczema will occasionally develop shield ulcers cataract.

How are Cataracts diagnosed

Cataracts are detected by finding lens opacification during a medical eye examination by an eye-care professional.. Usual eye tests include testing visual acuity, color vision, contrast sensitivity, and a thorough examination of all other parts of the eye. A thorough eye examination will make sure that vision loss is not due to other common eye problems, including diabetes, glaucoma or macular degeneration.

Who is a candidate for cataract surgery?

Surgery is recommended for most individuals who have significant vision loss and are symptomatic secondary to cataract. If you have significant other eye disease unrelated to cataracts that limits your vision, your ophthalmologist may not recommend surgery.

Cataract Surgery

Before the Procedure

Before surgery, the doctor will use ultrasound or a laser scanning device to determine the best IOL for you.

You may be prescribed antibiotic eye drops before the surgery.

Cataract removal is surgery to remove a clouded lens (cataract) from the eye, to help you see better. The procedure almost always includes placing an artificial lens (IOL) in the eye. Cataract surgery is performed by an ophthalmologist as an outpatient procedure.You likely do not have to stay overnight at a hospital

What are the techniques of cataract surgery?

There are three basic techniques for cataract surgery:

1. Phacoemulsification: This is the most common form of cataract removal surgery as no stitches are used to close the wound, and often no eye patch is required after surgery.

Phacoemulsification typically comprises of the fo.

  • Anaesthetic - The eye is numbed with using simple anesthetic eye drops.
  • Corneal Incision - Two cuts are made through the clear cornea to allow insertion of instruments into the eye.
  • Capsulorhexis - A needle or small pair of forceps is used to create a circular hole in the capsule (or bag) in which the lens sits.
  • Phacoemulsification - A handheld probe is used to break up and emulsify the lens into liquid using the energy of ultrasound waves. The resulting 'emulsion' is sucked away.
  • Irrigation and Aspiration - The cortex which is the soft outer layer of the cataract is aspirated or sucked away. Fluid removed is continually replaced with a salt solution to prevent collapse of the structure of the anterior chamber (the front part of the eye).
  • Lens insertion – An acrylic foldable lens is inserted to the capsular bag that is used to contain the natural lens.

2. Extracapsular cataract surgery: This procedure is used mainly for very advanced cataracts where the lens is too dense to dissolve into fragments (phacoemulsify). This technique requires a larger incision so that the cataract can be removed in one piece without being fragmented inside the eye. An artificial lens is placed in the same capsular bag as with the phacoemulsification technique. This surgical technique requires a various number of sutures to close the larger wound, and visual recovery is often slower.

3. Intracapsular cataract surgery: This surgical technique requires an even larger wound than extracapsular surgery, and the surgeon removes the entire lens and the surrounding capsule together. This method is rarely used today but can still be useful in cases of significant trauma. Cataract surgery recently performed, foldable IOL inserted. The surgery takes fifteen minutes to half an hour. If you have cataracts in both eyes, one eye is done, waiting at least 2 to 4 weeks between each surgery.

What are types of intraocular lenses for cataract surgery?

There are a variety of intraocular lens styles available for implantation, including monofocal, toric, and multifocal intraocular lenses.

1. Monofocal lens: These lenses are the most commonly implanted lenses today. They have equal power in all regions of the lens and can provide high-quality distance vision, usually with only a light pair of spectacles. Monofocal lenses are in sharpest focus at only one distance. They do not correct pre-existing astigmatism, a result of irregular corneal shape that can distort vision at all distances. Patients who have had monofocal intraocular lenses implanted usually require reading glasses.

2. Toric lens: Toric lenses have more power in one specific region in the lens to correct astigmatism as well as distance vision. Due to the difference in lens power in different areas, the correction of astigmatism with a toric lens requires that the lens be positioned in a very specific configuration.

3. Multifocal lens: Multifocal intraocular lenses are one of the latest advancements in lens technology. These lenses have a variety of regions with different power that allows some individuals to see at a variety of distances, including distance, intermediate, and near. While promising, multifocal lenses are not for everyone. They can cause significantly more glare than monofocal or toric lenses. Multifocal lenses cannot correct astigmatism, and some patients still require spectacles or contact lenses for clearest vision.

After the Procedure

Before you go home, you may receive the following:

  • A patch to wear over your eye until the follow-up exam
  • Eyedrops to prevent infection, treat inflammation, and help with healing

You will need to have someone drive you home after surgery.

You will usually have a follow-up exam with your doctor the next day.

Tips for safe recovery after cataract surgery:

Recovery takes about 2 weeks.

  • Wear dark sunglasses outside after you remove the patch.
  • Wash your hands well before and after using eye drops and touching your eye. Try not to get soap and water in your eye when you are bathing or showering for the first few days.
  • Light activities are best as you recover.

Most important -Keep your follow-up visit with your doctor.