Familial exudative vitreoretinopathy presentation as persist
To illustrate a presentation of familial exudative vitreoretinopathy (FEVR) that can be mistaken for persistent fetal vasculature (PFV) and the importance of wide angle fluorescein angiography in making this distinction. A patient was referred with a unilateral retrolental membrane and retinal detachment from PFV but was found to have FEVR.

A 4 month-old full-term infant was referred with the diagnosis of PFV based on findings of a dense retrolental membrane and microphthalmia in the left eye. The patient had a near-complete retinal detachment with some exudation. Wide-field fluorescein angiography of the right eye revealed avascular retina and leakage at the vascular/avascular junction. Genetic testing confirmed a mutation in FZD4, supporting the clinical diagnosis of FEVR. Prompt laser therapy to the avascular area in the right eye was performed and lensectomy/vitrectomy with membrane dissection was performed in the left eye.

Conclusions and importance
FEVR can present with great variability between eyes. In patients presenting with findings suggestive of PFV, careful bilateral examination with wide-field fluorescein angiography is helpful. Early diagnosis and treatment are important to preserve visual acuity, especially in the less affected eye.