Keratoconus is a disease characterised by deterioration in the shape of the cornea. The deterioration of the cornea also causes deterioration of vision over time. In progressive stages, vision gradually decreases. Apart from the effects on vision, this disease can also create an obstacle for the application of some different treatments. Naturally, there are some situations that raise questions in patients. One of these is whether phakic intraocular lenses can be used in patients with keratoconus.
What are the Conditions of Intraocular Lens Application in Patients with Keratoconus?
Phakic intraocular lens (ICL, Phakic Intraocular Lens) can be applied to patients with keratoconus. However, this should be done in carefully selected cases and under certain conditions. Since keratoconus is a progressive disease that weakens the structure of the cornea, this type of lens implantation should only be considered when appropriate stabilisation is achieved.
Stabilisation of the disease
Firstly, stabilisation treatments such as corneal cross-linking should be performed to stop the progression of keratoconus. When the corneal curvature remains stable and does not progress after stabilisation, this type of lens implantation can be considered.
Combination with Intra-Corneal Segments
In some cases, phakic intraocular lens implantation may be considered after corneal shape correction with intra-corneal rings (such as CAIRS or PMMA segments). In this way, both the corneal shape is corrected and the refractive error is eliminated.
When is it applied?
When Alternative Options for Vision Correction Are Inadequate
Depending on the patient’s degree of keratoconus and refractive error, phakic intraocular lens may be a good alternative if vision correction with glasses or contact lenses is insufficient and the patient is uncomfortable with the lenses.
If the patient’s refractive error is appropriate
In general, myopia up to -20.00 D and hyperopia up to +10.00 D can be corrected. However, astigmatism should also be considered in patients with keratoconus and the overall profile of the patient’s refractive error should be favourable for lens implantation.
Advantages of Phakic Intraocular Lenses
As there is no surgical intervention on the cornea (instead of cutting or thinning the corneal tissue), it can be a safe option for patients with keratoconus.
It is a reversible procedure; the lens can be removed when necessary.
