Which lenses are used in refractive lens exchange or cataract surgery?
Lens choice is one of the most important decisions for your surgery. Measurements (known as biometry) are taken prior to the surgery in order to ensure that the correct lens implant is used. This usually allows the surgeon to aim for a particular focus for the eye post-operatively. During your consultation, Mr Mitry will discuss with you the options available, which may be best suited to your visual requirements.
A standard (monofocal) lens implant will correct your distance vision as clearly as possible. Some people have some astigmatism, which means the cornea is more oval in shape than average. A toric lens will be required to treat astigmatism to provide properly focused vision. Many patients with monofocal lens implants benefit from monovision. This is where one eye is set for distance vision and the other for more near vision. This improves intermediate and near vision (particularly computer use) and in some cases individuals do not need reading glasses at all, however, not all patients are well suited to this correction.
Multifocal lenses can provide a far greater range of focus. Trifocal lenses target near, intermediate and distance vision and between 80-90% of people are spectacle-free with trifocal lenses. A small proportion of people may require reading glasses for some tasks. The potential downside of trifocal lenses is a comprise in the quality of distance vision as well as optical side effects (glare and haloes), particularly at night.
Extended Depth of Focus Lenses (EDoF) lenses let you see clearly at far and intermediate distances. A proportion of patients will however need reading glasses for certain print sizes. They provide greater spectacle independence than monofocal lenses, while inducing less visual side effects compared to trifocal lenses. This balance of increased spectacle independence and less visual phenomena is particularly attractive to patients with an active lifestyle, who wish to be spectacle- free for most of their daily activities but are more sensitive to halos and glare.
How safe is cataract surgery?
Modern cataract surgery is the most commonly performed elective operation globally. Despite every effort, in rare situations, complications can occur. The risk of a complication is significantly lower if the operation is performed by an experienced surgeon and if the complication is managed appropriately. The following are notable risks of cataract or refractive lens exchange surgery:
1 in 1000 (0.001%) risk of a serious complication such as an infection within the eye (which can occur a few days after the surgery) or bleeding within the eye (which can occur at the time of surgery).
1 in 100 (1%) patients may require a second operation on the same eye. This may be to re-position or insert an intraocular lens. Occasionally the lens can't be placed in the eye at the time of initial surgery and requires a second operation to do so.
1 in 10 (10%) patients can develop a membrane over the new intraocular lens. This is called posterior capsular opacification. This can result in vision becoming blurry again. If this does occur it can be treated by a simple outpatient laser procedure called a YAG laser capsulotomy.
How long does the surgery take?
Cataract surgery is performed as day case surgery and takes 15-20 minutes per eye. Commonly, both eyes can be carried out at the same time.
Vitrectomy surgery is also day case surgery and takes approximetely 1-1.5hrs.
What will my eye feel like after cataract surgery?
Your eye may feel a little sore after surgery and it can be a bit red. Patients often feel like they have a gritty feeling for several days after surgery. Some patients do not feel any discomfort. Most patients will not experience any major discomfort.
What will my vision be like with a trifocal lens?
Multifocal lenses are designed to give you as much independence from glasses as possible and have been a huge success. For most patients this means that they don't need to wear glasses for most daily activities. These lenses work by splitting the light that enters the eye into images for distance, intermediate and near vision. As a result, symptoms that occur in some patients with these lenses include haloes or star bursts particularly around bright light sources such as headlights at night. Some patients also report difficulty reading in dim light situations and in some cases a reduction in distance vision clarity. These symptoms often improve with time (neural adaptation) and are rarely.
See the vision simulator below for an idea of this glare/halo effect:
http://www.tecnisvisionsimulator.com/
Does cataract surgery get rid of floaters?
Cataract surgery does not get rid of floaters. Vitreous floaters are a common problem, which you may experience as a blob or dark spot that drift across your vision. Floaters generally increase with age and are more common in shortsighted patients. In certain situations, a different procedure called a vitrectomy can be done for floaters. This can be discussed with you if needed.
Will my insurance cover my treatment?
Mr Mitry is recognised by all major insurance companies. Policies differ in terms of the level of cover they provide. If you have any queries please contact Mr. Mitry's office.
What should I expect after vitrectomy surgery?
While some surface irritation is normal, the operated eye should not be overly painful after the surgery. However, looking at bright lights may be uncomfortable, so wearing sunglasses in the sun is recommended.
Afterwards, your eye may also appear red, and you may notice a pinkish watery discharge.
After vitrectomy surgery, your vision is blurred and hazy. This is due to the bubble of air in your eye preventing light from focusing properly on the retina. However, once the air is slowly absorbed (within a week), you will start to notice your vision clear up, with a wobbly black or silver line at the top of the area that you can’t properly see. As time goes by, this line will decrease in size and you will find you’ll eventually only be able to see the bubble of air when looking downwards. Before the air completely disappears, you may see one or more circles in the bottom of your vision. The air takes roughly one week to be absorbed completely. If gas has been used during the operation, it will take longer than air to absorb (4-6 weeks), resulting in a longer period of these effects on your vision.
