Cataract

Overview

Cataract is a congenital or degenerative opacity of the lens. The main symptom is gradual, painless vision blurring. Cataracts are the leading cause of blindness worldwide. Almost one in two people older than 75 has cataracts.

Clouded vision caused by cataracts can make it more difficult to read, drive a car (especially at night) or carry on daily work activities.

Cataract develops slowly and doesn’t actually disturb your eyesight in the early stages. But with time, cataract will lead to clouded vision and affect the quality of life.

Symptoms

The following symptoms and sings can point to cataract:
• Clouded, blurred or dim vision
• Increasing difficulty with vision at night
• Sensitivity to light and glare
• Need for brighter light for reading and other activities
• Seeing halo around lights
• Fading or yellowing of colors
• Double vision or diplopia

When to see a doctor

At first, the cloudiness in your vision caused by a cataract may affect only a small part of the eye’s lens and you may be unaware of any vision loss. As the cataract grows larger, it clouds more of your lens and distorts the light passing through the lens. You should see a doctor right away if you notice one of the noticeable symptoms or any changes in your vision.

Causes

Most cataracts develop when aging changes the tissue that makes up your eye’s lens. Some systemic disease (for example, diabetes) and inherited genetic disorders can increase your risk of cataracts. Cataracts can also be caused by trauma or past eye surgery.

Risk factors

• Increasing age
• Diabetes
• Excessive exposure to sunlight
• Smoking
• Obesity
• High blood pressure
• Eye injury or inflammation
• Prolonged use of corticosteroid medications
• Drinking excessive amounts of alcohol

Prevention

There are still no studies have proved the efficiency of any measures to prevent cataracts or slow the progression of cataracts. But doctors think several strategies in which you can significantly reduce risk of developing cataracts:
• Have regular eye examinations. It can help detect cataracts and other eye problems at their earliest stages.
• Quit smoking.
• Follow a healthy diet. Add to your ration a variety of fruits and vegetables. Contained therein antioxidants help maintain the health of your eyes.
• Wear sunglasses. Ultraviolet light from the sun may contribute to the development of cataracts.
• Reduce alcohol use.

Diagnosis

To determine whether you have a cataract, you will need a complex ophthalmic examination which includes visual acuity test, visual field test, measurement of intraocular pressure etc. Slit-lamp examination provides more details about the character, location, and extent of the opacity. This method allows to track the smallest changes in eye tissue structures.

Treatment

The only effective treatment for cataracts is surgery.

Cataract surgery involves removing the clouded lens and replacing it with a clear artificial lens. The most common method of cataract extraction is phacoemulsification because this procedure uses the smallest incision, thus enabling the fastest healing, and is usually the preferred procedure. Femtosecond lasers can be used in refractive laser-assisted cataract surgery to perform certain parts of the cataract surgery prior to phacoemulsification.

A plastic or silicone lens is almost always implanted intraocularly to replace the optical focusing power of the removed crystalline lens. The lens implant is usually placed on or within the lens capsule (posterior chamber lens). The lens can also be placed in front of the iris (anterior chamber lens) or attached to the iris and within the pupil (iris plane lens).