Hospiten Blog

Types of intraocular lens, characteristics and problems

Posted on 12-01-2022

If you are thinking about eye surgery, especially for cataracts or refraction problems, you may have heard about the different types of lenses available today. In this post we explain their advantages and the problems they are used to deal with.


What are intraocular lenses?

Intraocular lenses are artificial lenses designed to be biocompatible with the human eye, which are implanted surgically and are used to correct defects in the vision.

Also known as IOL, ocular lenses are classified in two large groups, according to their relationship with the eye’s natural lens:

  • Phakic intraocular lens: which are inserted without removing the natural lens
  • Pseudophakic intraocular lens: the natural lens is removed to implant these. (They are the type of lens used in cataract surgery)

These lenses are implanted into the patient's eye as an outpatient surgery procedure with local anesthesia. It is a painless outpatient procedure, so does not require hospitalization and the procedure usually takes less than an hour.


Type of intraocular lenses

There are many different types of intraocular lens that are currently available.

  • Phakic intraocular lenses, also called ICL Lenses or Implantable Collamer Lenses. These lenses are suitable to treat astigmatism, myopia and hyperopia. 

They are recommended in patients aged between 21 and 60. The procedure does not cause dry eye, and their polymer and collagen-based composition means they are very flexible and adaptable.

To opt for this type of surgery, you must have -0.5D to -18D myopia, +0.5D to +10D hyperopia or between 0.5D and 0.6D astigmatism. In addition, the patient must have a stable prescription for eye-glasses, with changes of no more than 0.5D in the last 12 months.

  • Pseudophakic intraocular lenses


Monofocals lenses



Monofocal pseudophakic intraocular lenses replace the crystalline lens and correct distance vision. They are suitable to see correctly from a distance of 2 m to the horizon.

They are frequently used in cataract patients who will continue to wear glasses for reading or close work after the operation.

Pseudophakic intraocular lenses give good vision at a distance and close up, but intermediate vision does not recover sharpness.

As with other pseudophakic lenses, they are used to correct cataracts.

Trifocal pseudophakic intraocular lenses give optimal vision at all three distances: near, intermediate and far. In addition to solving vision loss due to cataracts.


What cataracts are and how they affect your eyesight.

Intraocular lens problems


After the procedure to implant ICL lenses or pseudophakic lenses, the patient may see halos around points of light. This is an effect that reduces over time, but can be bothersome in the first weeks or months after the intervention.


Surgical recovery

Any intervention has certain associated risks. It is true that surgery to implant intraocular lenses is a common, quite safe procedure, but there are a low percentage of infections or complications associated with the surgery.


Incompatibility with certain conditions

Certain conditions or diseases like uveitis, inflammation of the uvea, or irregularities in the morphology of the posterior chamber of the eye are factors incompatible with these surgeries.


Dry Eye

In the case of phakic intraocular lenses, symptoms related to dry eye may appear. Although they are corrected with the use of artificial tears, the condition should be assessed in cases where vision loss is not excessively high.


Corneal inflammation

Inflammation of the cornea is common in intraocular lens surgery patients, especially if they have undergone previous eye surgery, or if they have suffered endothelial cell loss or corneal dystrophy.

If the cornea was healthy before the intervention, the inflammation should subside in one or two days.


Intraocular pressure

On occasions, after a procedure of this type, intraocular pressure can be increase for a short time. It usually gets better about 6 hours after the end of the procedure.

Despite all the problems that may be associated with the implanting of intraocular lenses, it must be pointed out that complications in this type of intervention occur in fewer than 5% of cases.


Reaction to topical anesthesia

Some people may have adverse reactions to anesthesia. However, this is not associated with the type of anesthesia applied in these procedures, but to a response the body may have to external agents.

As with any substance, exposure can lead to an unexpected adverse response.


Intervention: preparation and care

Implanting intraocular lenses is a simple, outpatient procedure, as we have previously mentioned. So, the only requirement is that the patient attend the appointment accompanied for help in the first hours after surgery.

Subsequently, postoperative care is simple and can be summarized as:

  • application of prescribed antibiotic and anti-inflammatory drops
  • attendance at scheduled check-ups
  • avoid immersing your head in pool or hot tub water
  • do not press on or rub the operated eye
  • do not apply make-up to the area in the days following surgery
  • protect your eyes from the sun with dark glasses

Any possible complications and side effects of implanting intraocular lenses are a very low percentage of cases compared to the advantages of recovering clear vision.


What cataracts are and how they affect your eyesight.