Persistent fetal vasculature
| Persistent fetal vasculature | |
|---|---|
| Other names | Persistent hyperplastic primary vitreous, congenital retinal detachment, non-syndromic congenital retinal non-attachment |
| Falciform fold of detached dysplastic retina encircles the persistent hyaloid artery that extends from the optic nerve head to the retrolental mass. | |
| Specialty | Ophthalmology |
| Symptoms | Defects including glaucoma, cataract, falciform retinal folds, funnel- or stalk-shaped retinal detachment, spontaneous fundus hemorrhage, and a congenitally small eye. |
| Complications | Retinal detachment, blindness, and glaucoma, among other chronic diseases. |
| Usual onset | Neonatal, most often within 1–2 weeks of birth. |
| Duration | Permanent. |
| Types | Unilateral and bilateral presentations of anterior, posterior, and combination types are possible. |
| Causes | Unknown; genetic factors prevalent in bilateral cases. |
| Risk factors | Premature birth. |
| Diagnostic method | Advanced medical imaging required, symptoms of concern include strabismus, nystagmus, and amblyopia. |
| Prevention | None. |
| Treatment | Surgical intervention to preserve affected eye(s). Extensive monitoring advised. |
| Prognosis | Varies; even if treated early, visual outcomes are often poor, though will not generally deteriorate later in life. |
| Frequency | Unknown. |
Persistent fetal vasculature (PFV), also known as persistent fetal vasculature syndrome (PFVS), and until 1997 known primarily as persistent hyperplastic primary vitreous (PHPV), is a rare congenital anomaly which occurs when blood vessels within the developing eye, known as the embryonic hyaloid vasculature network, fail to regress as they normally would in-utero after the eye is fully developed. Defects which arise from this lack of vascular regression are diverse; as a result, the presentation, symptoms, and prognosis of affected patients vary widely, ranging from clinical insignificance to irreversible blindness. The underlying structural causes of PFV are considered to be relatively common, and the vast majority of cases do not warrant additional intervention. When symptoms do manifest, however, they are often significant, causing detrimental and irreversible visual impairment. Persistent fetal vasculature heightens the lifelong risk of glaucoma, cataracts, intraocular hemorrhages, and Retinal detachments, accounting for the visual loss of nearly 5% of the blind community in the developed world. In diagnosed cases of PFV, approximately 90% of patients with a unilateral disease have associated poor vision in the affected eye.
The presentation of persistent fetal vasculature is generally classified into three forms: purely anterior, purely posterior, or a mix of both. Combined expressions of both classifications are by far the most common presentation, accounting for up to 62% of all cases. Purely posterior presentations are often considered to be the most extreme variant and have the least successful surgical and visual outcomes. The majority of PFV cases are unilateral, affecting only one eye, though roughly 2.4% to 11% of cases are bilateral, impacting both eyes. Bilateral cases have generally poor visual outcomes and warrant heightened intervention regardless of presentation. They also may follow an autosomal recessive or autosomal dominant inheritance pattern, while no inheritance patterns have been conclusively identified for unilateral cases.