PIOLs

PIOLs, or phakic intraocular lenses, are implants placed inside the eye to correct refractive errors while preserving the natural crystalline lens. Unlike conventional cataract or refractive lens procedures, the eye’s own lens remains in place, which helps maintain accommodation in many patients. PIOLs are typically considered for individuals with high myopia or hyperopia, significant astigmatism, or those who are unsuitable candidates for corneal refractive surgery.

Types of PIOLs include anterior chamber, iris-fixated, and posterior chamber designs. Anterior chamber PIOLs sit between the cornea and the iris, while iris-fixated lenses attach to the mid-peripheral iris. Posterior chamber PIOLs are placed behind the iris in the ciliary sulcus, often referred to as phakic posterior chamber lenses; the implantable collamer lens (ICL) is a common example. Surgical planning relies on measurements of anterior chamber depth, sulcus dimensions, and endothelial cell density to reduce the risk of complications.

Materials used are typically biocompatible polymers, with collamer being a common material for posterior chamber designs. The choice of PIOL type depends on ocular anatomy and refractive goals, as well as surgeon experience.

Risks and limitations include endothelial cell loss, cataract formation, glaucoma or elevated intraocular pressure, pigment dispersion, and rarely infection or lens decentration. Proper patient selection, precise sizing, and careful surgical technique are essential to minimize complications. PIOLs can be reversible by exchange or removal if needed, and regular postoperative monitoring is important to assess visual outcomes and eye health.

Overall, PIOLs offer an alternative refractive option for selected patients, providing high-quality visual correction while preserving the natural lens and accommodation when appropriate.