What are phakic lenses?
They are lenses that are implanted into the eye without replacing the patient’s natural crystalline lens.
When the lens is healthy and transparent and enables vision, but has a refractive problem, the patient can have a phakic intraocular lens implanted without removing the natural crystalline lens. "In simple terms, it involves internally inserting a lens that is similar to those that would normally be worn externally. They are not exactly the same, but the concept is similar," explains Dr Elies. "A small plastic lens with the correct optical power is implanted inside the eye to compensate for the refractive error."
In which cases does the crystalline lens need to be replaced by an intraocular lens?
Replacement is performed in two cases: when the crystalline lens does not work properly or when the lens is opaque, which is known as cataracts. "Cataracts cause the crystalline lens to become opaque and non-transparent. During the operation to remove the lens, we also correct the patient’s myopia, hyperopia or astigmatism."
In some patients, the lens remains transparent, but does not accommodate well, due to loss of mobility through ageing. This can be as a result of the patient having many dioptres or because they are over the age of 55 with presbyopia (old eyes). In such cases, it is often better to implant a prosthesis and provide them with an artificial lens.