What are cataracts? Its causes, treatments and the way to choose intraocular lenses

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What are cataracts?
Its definition and symptoms

Cataract is a disease of the eye lens (Crystalline lens) which becomes cloudy. Crystalline lens refracts light, in order to adjust the focus. The eye lens which is usually clear, becomes cloudy. Due to this, less light enters, and dispersion occurs. The clouded lens is because of the accumulation of insoluble proteins.
Cataracts can occur in their forties in certain people, it increases with aging, there are 8.4 % people in their fifties who have cataracts, 40% among people over 60 years old and more than 80 % among people over 70 years old.

What causes cataracts?

The main cause of cloudiness of crystalline lens is aging. Cataracts can also be caused by diabetes and atopic dermatitis. Long-term use of steroid medications, past eye injury and surgery as well as people having eye disease for a long time, can cause cataracts to develop.

Cataract surgery is the usual treatment

Cataracts treatments usually consist of surgery and eye drops.
Eye drops are used to delay cataracts occurring, however, it cannot remove the cloudiness of your eye lens. Surgery is the usual treatment for cataracts.

When your doctor confirms cataracts and when you have noticeable symptoms, it might be time to have cataract surgery. In most of the cases, you have cataracts in both of your eyes. In this case, cataract surgery may be done on an eye, followed by a certain period, then the other eye. Surgery takes usually 20mn to 30mn, however this depends on the situation of the eye which can take more time.

After cataract surgery, time of to get vision improvement depends on each person. Some can see much better from the day after surgery. For others, it can take about a month.

Cataract surgery lens types and its choices

Cataract surgery procedure consists to leave the anterior capsule and the lens capsule. Only the lens cortex and the contents of the lens capsule are removed. Intraocular lens is inserted instead. The 6 mm diameter intraocular lens is neatly fixed in the center of crystallin.

In the case of healthy eyes, you focus by changing the thickness of crystallin lens. It becomes thinner during a far vision and thicker during a near vision. In the case of intraocular lens, you cannot focus on different distances due to its fixed thickness. It is therefore important to choose the right type of intraocular lens. There are two main lenses: "Fixed-focus monofocal" and "Multifocal". "Fixed-focus monofocal" lenses are usually used in cataract surgery.

Cataract surgery lens types and its choices

"Fixed-focus monofocal" lenses

Intraocular lenses used in cataract surgery are generally "Fixed-focus monofocal" lenses. There are 3 types (far vision, medium vision, near vision) of intraocular lens depending on your which focus you wish to have.

If you drive and practice sports, an intraocular lens with a far vision will be the best for you. If you watch TV or cook, a medium vision lens would be more convenient. If you read or use a computer, a near vision lens is recommended. However, if you choose a near vision lens, you will require the use of glasses for medium and far vision.

"Multifocal" lenses

These lenses are bifocal lenses. There are some inconvenient points like the difficulty in focusing, difficulty in reading small characters in dark places, vision adaptation, not necessary covered by the public health insurance. If these difficulties persist, surgery can be done to change the lens.

Surgery results
Other advantages other than vision acuity improvement

Astigmatism and Myopia correction possible with an intraocular lens

There are diversifications in the function of intraocular lenses. Besides "Fixed-focus monofocal" lenses
and "Multifocal" lenses, some toric lens can correct astigmatism at the same time than cataract. Myopia can also be corrected. People using contact lenses will be able to get rid of them.

Improvement of depression symptoms and cognitive function after cataract surgery

Study on the difference of feeling and cognitive function on patients before and after a cataract surgery showed an improvement of depression symptoms and cognitive function after the surgery. Cataract surgery improves not only vision impairment but ameliorates quality of life. If cataracts make it difficult to see, do not hesitate to have a doctor check.

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