Cataract

What is cataract?

Cataract is an opacification of the natural lens of the eye. It is the most common cause of blindness in the world. Cataract development in adults is due to aging, sunlight exposure, smoking, under-nutrition, eye trauma, diseases of the body system, and to some medications such as steroids. More than half of the people over 65 have cataract. Patients with cataract usually complain of blurred images, unclear.

Cataract description – video presentation

Normal sight	Sight with cataract

What are the symptoms?

Common symptoms of cataract are:

• Blurred vision
• Reduced sight at night
• Frequent change of dioptres
• Color fading
• Increased sensitivity to light, the appearance of a halo around lights
• Double or multiple view

Warning! These symptoms may also occur in other diseases of the eye, so a specialist advice is absolutely mandatory!

What is the lens?

The lens is the part of the eye that helps focus light on the retina. The retina is a layer of photo-sensitive which sends visual signals to the brain. The lens is located immediately behind the iris, the colored part of the eye. The lens changes its form. It becomes round when we look at closer objects and flat when we look at distant objects. The lens is made up mostly of water and protein. It allows passage of light and focuses it on the retina. Sometimes, these proteins opacify a small portion of the lens. This is a cataract. In time, it extends to the entire surface of the lens, thus making it harder to view clearly.

Focusing an image with a healthy eye	Focusing the same image with an eye with cataract

What are the different types of cataract?

• Cataract due to aging: Most cataracts are related to aging
• Congenital cataract: Some babies are born with cataract or develop it early in life, often in both eyes. These cataracts should not affect the sight. If they do, tehy should be operated.
• Secondary cataract
• Traumatic cataract: Cataracts can occur immediately after a trauma. But it can develop after a few years, too.

Crystal lenses used in the treatment of cataract – Video Presentation

Cataract treatment

Initially, the cataract-affected sight may be improved by a new prescription for glasses or by stronger lighting. However, as the cataract progresses, surgery is the only solution. Cataract surgery becomes necessary when the daily patient’s activity is affected. The decision for surgery belongs to the pacient, though. If the patient has cataract at both eyes, they can not be operated simultaneously. Each eye will be operated separately.
Today, cataract surgery is one of the most safe and efficient operations.
The best way to treat cataract is to replace the natural opacified lens with a new transparent artificial lens. This new implant will always remain clear and will never require replacement. Therefore, lens choice is very important for a successful operation.
The natural lens is enclosed in a capsule, a coating that keeps it in place.
The currently most used modern surgical technique is called phaco-emulsification, short “faco”. In phaco-emulsification surgery, the surgeon opens the front of the capsule and inserts a probe in the opacified lens which is broken(emulsified) and aspires all particles resulted from the emulsification. This surgical technique requires an incision of 2.2-2.8 mm, resulting in much quicker healing. Once the procedure for removing the natural opacified lens complete, it is replaced by an artificial lens, called lens implant or IOL (intraocular lens). The most advamced implants are the foldable lens. They are made of a flexible material that allows them to be twisted (folded), so they can be implanted through that small incision mentioned above.
This is the extra-capsular operation.

Lens emulsification and aspiration of particles	Introduction of an artificial foldable lens

There are rare cases, when the natural lens is too hard to be emulsified by ultrasound (this happens a lot and if surgery is delayed much). In this situation, the surgeon has to extract the lens along with its capsule, making a larger incision. This is the intra-capsular cataract surgery.

Cataract Surgery – Video Presentation

After surgery

One of the advantages of the phaco-emulsification technique is that, through a small incision that does not require suturing and heals more quickly, it enables the patient to go home immediately after surgery and resume his normal activities in a very short time.
After cataract surgery, most patients will need glasses for reading. Glasses for distance vision may be removed afterwards. In most cases, complete healing occurs about two weeks after surgery, and new glasses may be prescribed.

How many types of artificial lens do we use?

• Rigid lens (unfoldable). Has the advantage of a lower price, but requires a larger incision (5-6 mm) with suture (stitching), resulting by default in a longer healing period. They are rarely used, only at the express request of the patient. Requires reading glasses after surgery.
• Monofocal lens of acrylate (Acrysof ®). Acrylate is a very good material, with good biological compatibility, with filter for ultraviolet (UV) invisible radiation and blue radiation of the visible spectrum. Requires reading glasses after surgery.
• Natural aspherical lens of acrylate (Acrysof ® IQ). It offers a better post-operative sight and a better contrast by reducing spherical aberrations. Being thinner than the others lenses, it requires an even smaller incision (1.8 – 2mm). Requires reading glasses after surgery.
• Multifocal lens (Acrysof ® REST ®). It is one of the newest and most revolutionary artificial lenses which allows the patients with cataract surgery to see clearly see at any distance without glasses. But it is also the most expensive type of lenses.

How many types of artificial lens do we use – Video presentation

What is the flow of a cataract surgery?

The eye must be examined carefully before the operation. Eye mesaurement is taken with special equipment and the power of the artificial lens to be implanted is determined (biometrics).
On the day of the surgery, the patient should be prepared with half an hour before.
During the operation, which normally lasts no more than 15-20 minutes, the patient is awake. Usually, local anesthetic is used to eliminate any unpleasant sensation and to prevent eye movement during surgery. Using special high-tech equipment (operatory microscope, ultrasound devices), the natural (malfunctioning) lens is replaced with an artificial lens. Lasers are not used during these procedures.