Cataracts: Causes, Symptoms and Treatment | Orbis

Cataracts: Causes, Symptoms and Treatment

Cataracts are the leading cause of blindness and visual impairment in the world, accounting for around 35% of global blindness according to the International Agency for the Prevention of Blindness. But what are cataracts, what are their main causes and what can be done to treat or prevent them?

Read below to find out more and discover what our teams are doing to help combat cataracts in communities around the world.

What Is a Cataract?

A cataract is a clouding of the lens – turning the lens from clear to yellow, brown or even milky white. This blocks the light from passing into the eye.

Over time, the cataract blocks more and more light entering the eye - causing vision loss and eventually blindness.

The lens is necessary to focus images onto the retina at the back of the eye. In a healthy eye, the lens is clear - allowing light to pass into the eye.

What a cataract looks like in a diagram

Cataract is the leading cause of avoidable blindness and vision loss in the world. According to the International Agency for the Prevention of Blindness, women are at greater risk than men of developing cataracts and are less likely to have access to services needed to treat them.

Causes of Cataracts

There are a number of factors that can cause or increase the risk of cataracts. These include:

  • Age
  • Genetic disorders
  • Eye injury
  • Smoking
  • Exposure to U.V. light
  • Diabetes
  • Obesity
  • Uveitis

Commonly, most cases of cataracts occur in older people, but they can appear at any age. Cataracts in children is known as ‘childhood cataracts’. Some babies are born with cataracts, most often due to environmental or genetic disorders. This is known as ‘congenital cataracts’.

A child cataract patient before surgery to remove it

Not just an age-related condition: children and babies can develop cataracts too

If cataracts in children are not treated in time, the child can become permanently blind as their vision fails to develop properly.

Symptoms of Cataracts

Having a cataract is like seeing a dirty spot on a window. As this dirty spot becomes bigger, you can see less and less until you can no longer see anything.

There are a number of signs of cataracts to look out for. The symptoms of cataracts include:

  • Clouded or blurred vision
  • Squinting or closing of eyes in response to bright light
  • Headaches developing from bright light
  • Halos and glare in the field of vision
What an adult cataract looks like

What an adult cataract looks like

Prevention of Cataracts

To reduce the risk of developing cataracts or to delay its onset, the World Health Organization recommends stopping smoking, limiting exposure to ultra violet light and maintaining a healthy body weight.

Denzil Can Move Forward With His Life After Cataract Surgery

May 15, 2019

According to the International Agency for the Prevention of Blindness, over 1.1 million people suffer from vision loss in the Caribbean, with Cataract accounting for 50% of this number.
Read full story

Treatment of Cataracts

Cataracts will not go away on their own and there are no medications or ‘traditional’ treatments that can restore clear vision in the eye. At the time this article was written, the only way to treat a cataract is an operation to remove the clouded natural lens and replace it with an artificial lens through surgery. The eye is never removed during the process.

It is generally suggested that to prevent permanent poor vision or even blindness, children who are born with cataracts must be treated within the first few months.

What Happens During Cataracts Surgery?

Cataract surgery involves removing the clouded natural lens in the eye, and replacing it with a clear, artificial lens implant.


Prior to cataract surgery, an ophthalmologist will perform a comprehensive eye exam to check the overall health of their patient's eyes, evaluate whether there are reasons why they should not have surgery and identify any risk factors they might have.

A refraction will also be performed to accurately determine the amount of nearsightedness, farsightedness and/or astigmatism a patient has prior to surgery. Additional measurements of a patient's eyes will be taken to determine the curvature of their cornea and the length of their eye.

These measurements are essential to help a cataract surgeon select the proper power of the intraocular lens and give the patient the best vision possible after surgery.


During cataract operations, including those performed by ophthalmologists on our Flying Eye Hospital or in partner hospitals, the patient is usually awake with anesthesia - topical or local. In some cases, such as childhood cataracts, general anesthesia is given. Cataract surgery usually lasts about 20 minutes.


Following cataract surgery, patients are usually required to wear an eye patch. Depending on their general health and how far they live from the clinic, the patient may go home the day of surgery, or may be asked to stay in hospital overnight.

Patients are usually asked to come for a check-up the following day after their surgery, where the eye patch is removed and the eye is examined. If the surgery is successful, the patient's vision will improve immediately.

The patient will often be given eye drops to help prevent infection. If the patient has cataracts in both eyes, one will be operated on initially and the second a few weeks or months later.

Some people may need glasses after their operation.

Cataract Surgical Techniques

The three most common cataract surgical techniques are extracapsular cataract extraction (ECCE), phacoemulsification (phaco), and small incision cataract surgery (SICS).


Extracapsular cataract extraction is traditionally the most common method, which involves a standard incision to remove the nucleus of the lens and insert a synthetic intraoccular lens.


Phacoemulsification uses an ultrasound probe to fragment the lens after making a small incision. A foldable intraoccular lens is inserted through the incision, and in most cases, sutures are not necessary. Phaco is the preferred method across the US, Canada and Europe due to the high success rate and quick recovery time, which is why our Volunteer Faculty are training eye teams in this method in communities around the world.


Small incision cataract surgery is a refined extracapsular cataract extraction technique. Similar to phaco, a small incision and foldable synthetic intraoccular lens are used.

More information about cataract surgery can be found on the International Agency for the Prevention of Blindness website.

Watch the video below of live cataract surgery via our online telehealth platform, Cybersight. Warning: contains graphic scenes of eye surgery.

A tutorial of phaco surgery put together by our Cybersight team

What We're Doing to Combat Cataracts Around the World

According to the International Agency for the Prevention of Blindness there are around 12 million people living with blindness and a further 52 million with mild-to-severe vision loss caused by this entirely preventable condition.

In many remote communities around the world, people remain blind from cataract due to a lack of access to quality eye care services. As you've read, all it takes to restore a person's sight is a 20-minute operation. But in many places in the world, people simply do not have access to the right kind of care.

This is where we step in. By using our amazing network of partners, supporters, staff and world leading volunteers, we empower local communities with the skills and resources necessary to fight blindness caused by cataracts on their own.

Gladys struck in the eye with a stick

May 30, 2017

Read full story

At Orbis, we're implementing a comprehensive approach to fighting blindness caused by cataracts:

Training: We train local partners on our Flying Eye Hospital, in local hospitals and via Cybersight. This way, we can strengthen skills and knowledge for local eye teams over all over the world, for generations to come.

Technology: We're running e-learning courses on Cybersight which improve knowledge and education, as well as offering training and support to eye teams around the world using the latest advancements in internet and mobile technologies.

Strengthening: By working with partners across the health service to establish and strengthen existing care, we help provide long-term, sustainable eye care to communities around the world. From rural areas to bustling cities, we aim to provide the tools and knowledge to help restore vision for generations to come.

Community: We want to make sure everyone has access to quality eye care, no matter where they live. This is why we work at a community level, training and educating people about the symptoms of cataracts and setting up referral networks to ensure even the most remote areas receive the best possible treatment.

Donate Today

Can you help help fight cataracts in communities around the world?

Close the modal
Sorry there was an error.
Try again