Persistent Fetal Vascular Syndrome (PFVS)

Figure 1A: Shows the stalk extending anteriorly from the apex of the tent-shape detachment in the simple posterior form of PFVS
Figure 1B: Shows a typical tent-shaped retinal detachment seen in PFVS. The apex occurs in an area of vascularized retina.
Figure 2. Shows a falciform fold in a child with FEVR and peripheral fibrovascular proliferation. The apex of the detachment is peripheral at the junction of vascular and avascular retina and the retina is pulled up into a falciform fold. On the crest is a retinal vessel that functions as the retinal skeleton. No stalk is seen.

Today, I did an EUA and laser on an approximately 10 mm eye with a severe configuration of PFVS. The initial vitrectomy was 2 weeks ago and it looks good but I am worried so I added treatment. There is no macula visible. ( I couldn't photograph because of the anterior fibrosis obscured the view)The eye is doing better than I expected, but the final result is still uncertain because although the retina is largely attached. There is a fold going superiorly off the disc to the ciliary body.

I am using the term PFVS because of my debt to Morton Goldberg who hired me at UIC when I was a young and naive graduate from retina fellowship. PFVS is a good term, but I also like Persistent Hyperplastic Primary Vitreous (PHPV) label. In particular, I like the hyperplastic because fibrous overgrowth and traction plays a central role in the cases that come my way. Between primary vitreous or fetal vasculature, fetal vasculature is definitely more accessible. I have read a good deal of embryology and still forget the meaning of primary vitreous. But it refers to the hyaloid vasculature. I wish we called it persistent and hyperplastic fetal vasculature. In any case this condition is a congenital anomaly that extends from trivial to devastating. Usually, the degree of microphthalmia and the extent of the retrolential fibrosis and traction will track with the severity of the anomaly.

This case is of special interest to me because it was not like the photograph above and seemed like a challenge to my understanding of falciform folds that I have taught my fellows and lectured on recently in Japan. In general, the detachment of ROP, FEVR, Norrie etc arises from traction peripherally related to fibrovascular proliferation that grows because of a peripheral avascular zone. The crest of the fold has retinal blood vessels going up toward the peripheral traction Figure 2. In distinction the classic retinal detachment in PFVS is more tent like than falciform and has a stalk that goes centrally from the apex of the retinal detachment Figure 1A and 1B.

Today's patient had a major retrolental fibrous proliferation with obvious fetal vasculature and no avascular zone the detachment was wing shaped and its apex was involved with the retrolental mass. There was a short stalk, however when you look at the crest of the fold there were vessels that extended out to the peripheral retrolental mass.

After considering the configuration it mainly shows that severe traction causes a change in the configuration from tent-shape to wing-shape. Looking back at figure 1B I can imagine nascent wings that elevate, extend and thin out as the stalk is pulled into the retrolental mass.

Enough for today, I would like to discuss the retina configuration of toxocara canis and hope that I get the video system at LGH up and running.