Astrocytes form an outer limiting membrane to interact with the pia.

The external limiting membrane (or outer limiting membrane) is one of the ten distinct layers of the retina of the eye.

In cestodes the tegument is further covered with highly specialized microvilli, called "microtriches", projecting from the outer limiting membrane of the tegument.

In early development of the retina, the medullary epithelial cells acquire polarity, such that a basement membrane associated with the vitreous forms the internal limiting membrane on one side, while terminal bars form the outer limiting membrane on the other side.