PHPV represents an abnormal regression of the primitive hyaloid vascular system in the eye. This produces a fibrovascular stalk that connects the optic disc and the posterior part of the lens (posterior cataract). A retrolental membrane forms at the posterior part of the lens and it may extend to the ciliary processes. Over time, the membrane can contract, pulling the ciliary processes centrally. If left untreated, severe forms of PHPV can lead to shallowing of the anterior chamber and angle closure glaucoma.