Persistent Pupillary Membrane

Persistent Pupillary Membrane: A Congenital Canine Vision Problem

In normal circumstances, dogs develop in the womb with a thin film called the pupillary membrane covering each eye. The idea is that since the animal is not yet sighted anyway, this won't interfere with vision and is the most efficient way to supply blood to the developing organ. It usually can still be seen once a dog is born but dissolves on its own within the first few days. In some cases, however, this membrane refuses to dissolve and can cause problems; this is known as a persistent pupillary membrane.The membrane is made up of thin but tough strands of a silk-like film. Depending on how much of the membrane persists after birth, these strands can be located in any number of places and their location determines to a large extent how much of a problem the persistent pupillary membrane will cause. The strands can stretch across the entire pupil, from the pupil to the lens, from the iris to the cornea, or they can be free-floating, attached at only one eye. [...]

Comments

Email to a Friend