Cataract

Two main types of surgical procedures are in common use throughout the world. The first procedure is phacoemulsification (phaco) and the second involves two different types of extracapsular cataract extraction (ECCE). In most surgeries an intraocular lens is inserted. Foldable lenses are generally used for the 2-3mm phaco incision, while non-foldable lenses are placed through the larger extracapsular incision. The small incision size used in phacoemulsification (2-3mm) often allows “sutureless” incision closure. ECCE utilises a larger incision (10-12mm) and therefore usually requires stitching, and this in part led to the modification of ECCE known as manual small incision cataract surgery (MSICS).

Phacoemulsification is the most commonly performed cataract procedure in the developed world. However, the high cost of a phacoemulsification machine and of the associated disposable equipment means that ECCE and MSICS remain the most commonly performed procedure in developing countries.

Cataract surgery is a relatively straightforward procedure that usually takes 15 to 20 minutes.

It’s often carried out as day surgery under local anaesthetic, which means you’ll be awake during the procedure and can go home on the same day.

During the operation, the surgeon will make a tiny cut (incision) in your eye so they can remove the affected lens. After it’s been removed, a small plastic lens called an intraocular implant or intraocular lens will be inserted.

There are now many different lens options available to patients. Currently, the following types of lenses available are:

Standard lens (monofocal) – This high-quality, clear lens delivers excellent vision at only one distance. The focal point or distance at maximum clarity can be set to distance (driving, golfing, watching TV), intermediate (grocery store shelves, computer, car dashboard), or near (reading, hobbies). There is no extra out-of-pocket cost with a monofocal lens.

Multifocal lens – Designed to reduce your need for eyeglasses for both distance and near vision, this lens gives you clear vision at several distances. This lens is usually more expensive.

Toric lens – Designed to treat astigmatism and deliver excellent vision at a single distance.

Aspheric lens – Designed to improve contrast sensitivity and visual clarity under certain circumstances.

The risk of serious complications developing as a result of cataract surgery is small.
The most common complication is a condition called posterior capsule opacification (PCO), which can cause your vision to become cloudy again. In PCO, a skin or membrane grows over the back of the lens implant months or years later.

If necessary, PCO can be treated with a simple laser eye surgery procedure to cut away the membrane.

Other risks or complications of cataract surgery are much rarer and can include:

• tearing of the lens capsule, the “pocket” that holds the lens in place
• all or some of the cataract dropping into the back of the eye
• inability to remove all of the cataract or insert a lens implant
• infection or bleeding in the eye

Most complications that can potentially develop after cataract surgery can be treated with medication or further surgery, and don’t usually have a long-term impact on your vision.
However, there’s a very small risk – around 1 in 1,000 – of permanent sight loss in the treated eye as a direct result of the operation.

Most people’s sight will improve soon after having cataract surgery, although vision may be blurred for a few days.

Eventually, you should be able to:

• see things in focus, although glasses are often needed
• look towards lights without as much glare
• tell the difference between colours, which will seem brighter

Most people need to wear glasses for near or distance vision – or both – after cataract surgery. This is because artificial lens implants can’t focus on a range of different distances.
The surgeon will normally aim for more focused distance vision, with dependence on reading glasses for close up work, although this depends on the strength of your glasses and individual circumstances.

With glasses, most people have a good enough level of vision to be able to drive and carry out everyday activities without any problems.
Your vision may not be restored to normal if you also have another eye condition or in the rare event of a serious complication.

Usually two days: the first day we carry out investigations, if these are okay then you can undergo surgery on the next day. Most patients go home the same day of the surgery.

With a standard monofocal lens implant, the vision will be very clear in the distance but very blurry up close (for reading) without glasses. Some patients have even complained that they could not see their food at the dinner table without using reading glasses. Multifocal lenses were developed to allow patients to see well at several distances WITHOUT GLASSES after cataract surgery. Multifocal lenses offer benefits above and beyond those of standard lenses but are more expensive than standard lenses.

Eye diseases, such as glaucoma, diabetic retinopathy, diabetic macular edema, or macular degeneration, can negatively affect the health of the eyes and the quality of the vision. These diseases, even in early stages, could cause problems with premium lenses.

A multifocal lens is not recommended if you have one of these eye diseases:

Astigmatism is an irregular curvature of the cornea. Instead of being round like a basketball, the cornea is shaped more like a football or a spoon. Patients with moderate astigmatism are therefore not good candidates for a multifocal lens.

Visual needs should also be considered when deciding on a multifocal lens. The technology contained in these lenses that allows you to read without glasses may lead to mild symptoms such as glare, halos, or decreased contrast sensitivity in certain conditions, such as night driving or dim restaurant lighting. Some patients rarely notice visual effects related to the lens implant. Others notice the effects but are not significantly bothered by them. If you feel you would not be able to adapt to these visual symptoms, you probably are not an ideal candidate for a multifocal lens.

Motivation to not wear glasses should also be determined when selecting a multifocal lens. These lenses are designed for patients who are motivated to not have to wear glasses after their cataract surgery. Some patients are accustomed to wearing glasses and do not mind using them after surgery. The additional cost of a multifocal lens would not be a reasonable investment for these patients. For other patients, eliminating the need for glasses is a strong desire. Paying the additional out-of-pocket cost for a special lens would make much more sense for these patients, as these lenses would give them the best option to achieve their goal to be free from glasses.

In summary, ideal candidates for multifocal lenses are patients with healthy eyes, little to no astigmatism, motivation to be less dependent on eyeglasses or contact lenses, and willingness to adapt to minor visual effects from the lens. Patients selecting a multifocal lens can reasonably expect to have good vision for reading and driving. Because no current technology is perfect there may still be circumstances where glasses are required to achieve comfortable vision.