Types of Intraocular Lenses
There are several types of intraocular lenses which can be implanted during cataract surgery depending on patients’ visual needs and subject to previous thorough measurements.
Standard monofocal intraocular lenses provide clear vision at a certain distance (far, intermediate or near vision).
Astigmatism is a common condition and refers to an irregular curvature of the cornea and/or the lens of the eye. When the eye has significant astigmatism the shape of the cornea is oval and not perfectly round like a sphere.
Toric intraocular lenses address the astigmatism and they need to be implanted at a certain angle inside the eye.
Multifocal intraocular lenses provide clear vision at near, intermediate and far distances and negate the need to use glasses following surgery. This type of lens focuses both light rays from distance and near at the same time and the brain accommodates to respond to the desired image. They may cause some glare and loss of contrast sensitivity. Not all patients are suitable for this type of lenses and anyone desiring this lens will need to be carefully counselled.
Toric multifocal lenses combine the advantages of both toric and multifocal lenses as previously described.
Based on the above and depending on each patient’s visual needs, different types of lenses can be implanted in each eye to achieve the ideal outcome depending on individual circumstances. This means that eyes can have standard monofocal lenses, toric lenses, toric multifocals or one eye can be corrected for distance vision and the second one (non dominant) can be adjusted for intermediate or near vision. Sometimes it is important to simulate above conditions with the use of contact lenses prior to surgery to determine how the individual patient would tolerate the planned outcome following cataract surgery.
