sixpenceee:Persistent pupillary membranes are strands of tissue in the eye. They are remnants of blo
sixpenceee:Persistent pupillary membranes are strands of tissue in the eye. They are remnants of blood vessels which supplied nutrients to the developing lens of the eye before birth. Normally these strands are gone by 4 or 5 weeks of age. PPM can be seen in young dogs and can debilitate vision. (Source) -- source link