A persistent pupillary membrane results from an abnormality relating to fetal development. As the eye of the normal fetus develops, there are some blood vessels within the eye that are present only in the early stages of development. These vessels normally lose function and deteriorate. Occasionally, however, the deterioration is incomplete, and small strands of abnormal tissue are left within the eye chambers. These fibrous strands may actually crisscross the eye chambers and attach to the lens and/or cornea. A corneal opacity may be seen. There is no treatment and the condition may be inherited in Basenjis.