Phakic

Phakic is a term used in ophthalmology to describe an eye that retains its natural crystalline lens. The word contrasts with aphakic eyes, which lack a lens, and pseudophakic eyes, in which an artificial intraocular lens has replaced the natural lens. The term and the related concept of phakia derive from the Greek phakos, meaning lens.

In clinical practice, phakic status is relevant in refractive assessment and surgical planning. Because the natural lens remains in place, phakic eyes may have age-related changes or other risk factors that influence decisions about refractive procedures and cataract risk. To correct refractive errors without removing the natural lens, surgeons may use phakic intraocular lenses, implanted either in front of the iris or behind the pupil, in a position that preserves the native lens. These implants are commonly used to treat high myopia or other refractive errors when corneal refractive procedures are unsuitable.

Risks and considerations for phakic lenses include the potential for cataract formation in the crystalline lens, changes in intraocular pressure or glaucoma, endothelial cell loss if the implant is placed in the anterior chamber, and various long-term biocompatibility concerns. The choice between phakic lenses and other corrective options depends on refractive error, age, anterior segment anatomy, and individual cataract risk.