What is a Cataract?
Cataract is the cloudiness of the natural crystalline lens inside your eye, where it becomes progressively misty and it feels as though you are looking through fog or a dirty camera. This is a part of the natural ageing process along with presbyopia (the loss of close-up vision). When you are young, the lens in the eye is so elastic and moves so well that it is accommodating (like the autofocus function in a camera) and as a child you are able to read small print as well as seeing distant objects comfortably. With older age, around 40, the lens loses its elasticity and is no longer able to see small print and hence most people will ask for reading glasses. The power of reading glasses will increase with increasing age when the lens loses its elasticity further. Furthermore, the lens starts to lose its clarity from around age 50, here it looks yellowish and you start to lose some contrast and the ability to see vivid colours as you used to do when you were younger. Later, the lens starts to lose its clarity and becomes cloudy which is what we call cataract development or age-related cataracts. Age related cataract normally occur in those over the age of around 60, it can happen in both your eyes and could vary in stage between the two eyes and tends to get progressively worse with time.
The back of your eye is the retina, this works like the film in a camera, when light is focused and hits the retina, an image is taken and sent to the brain. The front part of your eye, your cornea works like the lens; when a cataract begins to form, it can make the lens misty and cloudy.
Traumatic cataract can appear when the natural crystalline lens is damaged as a result of an eye injury. This can impede the vision in the same way and would be removed through surgery.
Congenital cataracts This happen when a child is born with cataracts that could be advanced needing urgent surgery in the first 6-8 weeks of life. It has the potential to lead to blindness and irreversible damage to the visual system if not operated within 6-8 weeks of birth. Cataract in new-borns is rare and affects 3-4 per 100,000 children in the UK. It accounts for 5% to 20% of blindness in children worldwide.
Developmental Cataract starts at a young age and can progress to become visually significant to require surgery. Any cataract or lens opacity that is present in a child less than 12 years of age could lead to permanent loss of visual potential in the affected eyes unless treated. Sometimes, occlusion therapy by patching the good eye to keep enough stimulation in the affected (cataract) eye. But surgery ultimately becomes necessary.
Secondary Cataract develops at any age and is usually secondary to disease, irradiation or medications. Glaucoma and diabetes are know diseases to contribute to cataract development. Steroids are one of the medications that are known to cause cataract, mainly posterior sub capsular cataract, that describes where is the cataract located within the lens.
Cataract is responsible for 51% of world blindness, which represents about 20 million people (WHO, 2010)
Signs and Symptoms of a Cataract
- Difficulty seeing in dim lighting or darker conditions like night time driving
- Colours appear dim and faded
- Your vision will get progressively worse, you may find your glasses are no longer useful
- Bright lights may be dazzling and halos or rings may appear around them
- You may feel as if you are looking through a misty window with a yellow or brown tinge
Can I have Cataract Surgery?
People of any age that show a significant lens clouding may be suitable for cataract surgery, a thorough eye examination and comprehensive diagnostic tests can confirm the suitability of surgery.
Can I have the new laser cataract surgery/ blade-less cataract surgery?
The use of femtosecond lasers within cataract surgery is becoming more common. Femtosecond lasers are used to minimise the use of surgical blades and needles providing precision and micron accuracy. The femtosecond laser constructs the wound and then breaks up the cataract in approximately 50 seconds allowing the surgeon to extract the broken up cataract and introduce the artificial lens. Laser cataract surgery (or, more accurately, laser-assisted cataract surgery) is fairly new and significantly increases cataract surgery cost, primarily because the laser machine is very expensive. While studies have shown that lasers can improve accuracy during the procedure, they may not necessarily improve cataract surgery safety, recovery time and visual outcomes in every case.
Can we Prevent the Incidence of Cataracts?
There are doubts whether cataracts could be prevented. It was shown that certain nutrients and nutritional supplements may reduce the risk of cataract development like taking vitamin E (almond, spinach, other green leafy vegetables and sunflower seeds), carotenoids lutein and zeaxanthin from food and nutritional supplements. Antioxidants like vitamins C and omega-3 fatty acids may also lower the risk or delay cataract formation.
Finally, UV light is known to accelerate the development of cataract and therefore, wearing protective sunglasses can be useful.