Ectopia lentis refers to the crystalline lens displacement - the crystalline lens is outside its normal postion. This makes the crystalline lens become dislocated or free-floating, in the vitreous, or in the anterior chamber, or on the retina.
Ectopia lentis is a rare disease, and it is often due to traumatic injuries. Ectopic lentis can be genetic. For instance, Marfan syndrome may sometimes cause ectopic lentis. The following ocular diseases may also lead to ectopic lentis: congenital glaucoma, retinitis pigmentosa, hypermature cataract, high myopia.
Ectopia lentis often cause decreased or impaired vision. If the cause is congenital, amblyopia may occur.