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  6. What are the risks?
  1. Phakic Intraocular Lenses

What are the risks?

Implanting a phakic lens involves a surgical procedure. As in any other medical procedure, there are risks involved. That's why it is important for you to understand the limitations and risks of phakic intraocular lens implant surgery.

Before undergoing surgery for implantation of a phakic intraocular lens, you should carefully weigh the risks and benefits and try to avoid being influenced by other people encouraging you to do it.


  • You may lose vision. Some patients lose vision as a result of phakic lens implant surgery that cannot be corrected with glasses, contact lenses, or another surgery. The amount of vision loss may be severe.
  • You may develop debilitating visual symptoms. Some patients develop glare, halos, double vision, and/or decreased vision in situations of low level lighting that can cause difficulty with performing tasks, such as driving, particularly at night or under foggy conditions.
  • You may need additional eye surgery to reposition, replace or remove the phakic lens implant. These surgeries may be necessary for your safety or to improve your visual function. If the lens power is not right, then a phakic lens exchange may be needed. You may also have to have the lens repositioned, removed, or replaced, if the lens does not stay in the right place, is not the right size, and/or causes debilitating visual symptoms. Every additional surgical procedure has its own risks.
  • You may be under treated or over treated. Many treated patients do not achieve 20/20 vision after surgery. The power of the implanted phakic lens may be too strong or too weak. This is because of the difficulties with determining exactly what power lens you need. This means that you will probably still need glasses or contact lenses to perform at least some tasks. For example, you may need glasses for reading, even if you did not need them before surgery. This also means that you may need a second surgery to replace the lens with another, if the power of the originally implanted lens was too far from what you needed.
  • You may develop increased intraocular pressure. You may experience increased pressure inside the eye after surgery, which may require surgery or medication to control. You may need long-term treatment with glaucoma medications. If the pressure is too high for too long, you may lose vision.
  • Your cornea may become cloudy. The endothelial cells of your cornea are a thin layer of cells responsible for pumping fluid out of the cornea to keep it clear. If the endothelial cells become too few in number, the endothelial cell pump will fail and the cornea will become cloudy, resulting in loss of vision. You start with a certain number of cells at birth, and this number continuously decreases as you age, since these cells are not replenished. Normally, you die from old age before the number of endothelial cells becomes so low that your cornea becomes cloudy. Some lens designs have shown that their implantation causes endothelial cells to be lost at a faster rate than normal. If the number of endothelial cells drops too low and your cornea becomes cloudy, you will lose vision and you may require a corneal transplant in order to see more clearly.
  • You may develop a cataract. You may get a cataract, clouding of the natural lens. The amount of time for a cataract to develop can vary greatly. If your cataract develops and progresses enough to significantly decrease your vision, you may require cataract surgery your doctor will have to remove both your natural and your phakic lenses.
  • You may develop a retinal detachment. The retina is the tissue that lines the inside of the back of your eyeball. It contains the light-sensing cells that collect and send images to your brain, much like the film in a camera. The risk of the retina becoming detached from the back of your eye increases after intraocular surgery. It is not known at this time by how much your risk of retinal detachment will increase as a result of phakic intraocular lens implantation surgery.
  • You may experience infection, bleeding, or severe inflammation (pain, redness, and decreased vision). These are rare complications that can sometimes lead to permanent loss of vision or loss of the eye.
  • Long-term data are not available. Phakic lenses are a new technology and have only recently been approved by the FDA. Therefore, there may be other risks to having phakic lenses implanted that we don't yet know about.


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