Persistent Fetal Vasculature
Persistent fetal vasculature (PFV), previously known as persistent hyperplastic primary vitreous, is a congenital anomaly thought to result from failure of the primary vascular vitreous to regress. The disorder is unilateral in 90% of cases and usually has no associated systemic findings. Anterior, posterior, and combined forms of this developmental abnormality have been described. Most cases are sporadic, but PFV can occur as either an autosomal recessive (mutations in the ATOH7 gene) or autosomal dominant trait. In some patients with mutations, the disease can be asymmetric and bilateral, with the fellow eye showing variable changes, including avascularity. See BCSC Section 6, Pediatric Ophthalmology and Strabismus, for more on PFV.
Anterior persistent fetal vasculature
In anterior PFV, the hyaloid artery remains, and a white vascularized fibrous membrane or mass is present behind the lens. Associated findings include microphthalmos, a shallow anterior chamber, and elongated ciliary processes that are visible around the small lens. Leukocoria is often present at birth. A dehiscence of the posterior lens capsule may, in many cases, cause swelling of the lens and cataract as well as secondary angle-closure glaucoma. In addition, glaucoma may result from incomplete development of the chamber angle.
The natural course of anterior PFV may result in blindness in the most advanced cases. Lensectomy and removal of the fibrovascular retrolental membrane prevent angle-closure glaucoma in some cases; however, growth of a secondary cataract is common. Deprivational and refractive amblyopia is a serious postoperative challenge in these patients.
Anterior PFV should be considered in the differential diagnosis of leukocoria. Differentiating it from retinoblastoma is particularly important. Unlike PFV, retinoblastoma is usually not obvious at birth, is more often bilateral, and is almost never associated with microphthalmos or cataract. PFV is anterior in the eye at birth; retinoblastomas do not appear in the anterior fundus until well after birth. Ancillary testing, such as diagnostic echography and x-ray techniques to look for calcification within the retinoblastoma, can be helpful in differentiating the 2 disorders.
Posterior persistent fetal vasculature
Posterior PFV may occur in association with anterior PFV or as an isolated finding. The eye may be microphthalmic, but the anterior chamber is usually normal and the lens is typically clear and without a retrolental membrane. A stalk of tissue emanates from the optic nerve head and courses toward the retrolental region, often running along the apex of a retinal fold that may extend anteriorly from the optic nerve head, usually in an inferior quadrant. The stalk fans out circumferentially toward the anterior retina. Posterior PFV should be differentiated from retinopathy of prematurity (ROP), familial exudative vitreoretinopathy, and ocular toxocariasis. Surgical repair of posterior PFV consists of lensectomy and vitrectomy, which result in formed vision in about 70% of cases.
Goldberg MF. Persistent fetal vasculature (PFV): an integrated interpretation of signs and symptoms associated with persistent hyperplastic primary vitreous (PHPV). LIV Edward Jackson Memorial Lecture. Am J Ophthalmol. 1997;124(5):587–626.
Sisk RA, Berrocal AM, Feuer WJ, Murray TG. Visual and anatomic outcomes with or without surgery in persistent fetal vasculature. Ophthalmology. 2010;117(11):2178–2183.
Excerpted from BCSC 2020-2021 series: Section 10 - Glaucoma. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.