In modern cataract surgery, the clouded crystalline lens is removed and replaced by an artificial intraocular lens (IOL). Intraocular lenses represent a highly innovative technology – both in terms of corrective power and the quality of vision provided. Different types of intraocular lenses are available today, enabling good vision at one, two or all three distances:
Intraocular lenses can simulate the refractive properties of the natural lens, however they do not have the ability to accommodate. Advanced intraocular lenses are available to meet patient’s individual vision requirements. Depending on the design, these IOLs can offer further benefits, such as improved contrast perception.
Intraocular lenses are usually made of a soft, synthetic, and biocompatible material. A typical IOL measures approximately between 11 and 13 mm in diameter. The thickness of the lens can vary, depending on its refractive power. The corrective power of the lens is individually calculated and may differ for each eye. An IOL is transparent and neither visible nor perceptible in the eye.
There are different types of intraocular lenses available today. Generally, there is a distinction made between standard and advanced intraocular lenses, also known as premium intraocular lenses.
Standard intraocular lenses are the most commonly used intraocular lenses in cataract treatment. They have one focal point and can improve vision at one distance: far or near. These lenses are called monofocal lenses. For the remaining distances, the patient may still need to use glasses.
Advanced IOLs are lenses that offer additional advantages on top of treating the cataract. They provide the possibility of being less dependent on glasses for different activities. Advanced IOLs include so-called multifocal lenses, EDoF (Extended Depth of Focus) lenses and lenses with added functionalities, such as aspheric or toric IOLs.
Multifocal intraocular lenses have two or three focal points and restore vision at more than one distance, giving the patient a chance of being more independent of glasses. Multifocal lenses include bifocal and trifocal IOLs, with the latter representing the most advanced technology. Trifocal IOLs allow the highest level of independence from glasses, enabling patients to see clearly at all three distances without them.
EDoF Intraocular lenses provide also a high extend of spectacle independence while inducing less visual side effects at night, compared to multifocal IOLs.
Added capabilities in advanced IOLs, such as aspheric or toric functions, allow the correction of pre-existing vision disorders, such as astigmatism, as well as some visual disturbances caused by light phenomena. Due to their special optic design these types of lenses can improve contrast sensitivity and general image quality.
Advanced IOLs allow patients to become less dependent on glasses, and are a good option for patients with active lifestyles and for those wanting more freedom from glasses. Since what they offer are additional benefits for patients, cataract treatment with premium lenses is – depending on in which country you live – not covered by health insurance.