Persistent Fetal Vasculature: A Parent’s Guide
Understanding Persistent Fetal Vasculature
While a baby is growing in the womb, a network of tiny blood vessels forms inside the eye. These vessels supply nutrients to the developing lens and retina. There are two parts to this network: the tunica vasculosa lentis, which is a mesh of blood vessels surrounding the lens, and the hyaloid system, which connects these vessels through the gel inside the eye back to the optic nerve.
In a healthy pregnancy, these blood vessels complete their job and disappear on their own by about the eighth month of pregnancy. By the time a baby is born at full term, these structures are gone and the eye is ready to function normally.
In PHPV, some or all of these fetal blood vessels fail to regress. Instead of disappearing, they persist and form a fibrovascular membrane, which is a sheet of tissue made of blood vessels and scar-like material. This membrane typically sits behind the lens of the eye.
The leftover tissue can interfere with normal vision by blocking light from reaching the retina. While PHPV itself does not worsen over time, the eye continues to grow during childhood. This growth can pull on the abnormal tissue, creating tension that may lead to complications later.
PHPV is divided into three types based on where the abnormal tissue is located inside the eye.
- Anterior PHPV affects the front of the eye, near the lens. This is generally the form with the best chance of a good visual outcome after treatment.
- Posterior PHPV affects the back of the eye, closer to the retina and optic nerve.
- Combined PHPV involves both the front and back of the eye.
Who Is Affected and Risk Factors
PHPV is a relatively uncommon congenital condition. About 90% of cases affect only one eye (AJNR Case Collections). When only one eye is involved, the child usually has no other health problems related to the condition. Bilateral cases, where both eyes are affected, are less common and may be linked to other medical conditions.
In most cases, no specific cause can be identified. However, several associations have been documented.
- Fetal alcohol syndrome, which results from alcohol exposure during pregnancy.
- Fetal hydantoin syndrome, linked to certain anti-seizure medications taken during pregnancy.
- Midline congenital cranial defects, which are structural abnormalities of the skull and brain.
When PHPV occurs in both eyes, it has been linked to chromosomal conditions including trisomies 13, 15, 18, and 21. In rare cases, a hereditary pattern has been identified. One Egyptian family study described autosomal dominant inheritance, meaning the condition was passed from parent to child through a single copy of an altered gene (Galal et al., 2006). However, most cases of PHPV occur sporadically with no family history.
Signs and Symptoms
The most common sign that parents or a pediatrician will notice is leukocoria, a white or yellowish reflection in the pupil. Instead of the normal dark pupil or red reflex seen in photos, the affected eye may show a white glow. This is sometimes first spotted in flash photographs.
Parents may also notice that the affected eye appears smaller than the other eye. This is called microphthalmos, meaning the eye did not grow to its full size during development.
A white pupil in a child must be evaluated promptly because it can be a sign of several serious conditions. PHPV is described as the second most common cause of leukocoria in infants (AJNR Case Collections). Retinoblastoma, a cancer of the eye, is another cause. Other conditions that can produce a white pupil include congenital cataract, retinopathy of prematurity, retinal detachment, Norrie disease, and Coats disease.
If you notice a white reflection in your child's eye, contact your pediatrician or a retina specialist right away. Early evaluation is critical to rule out life-threatening conditions and begin treatment.
While PHPV does not progress on its own, the growth of the eye during childhood can cause the persistent tissue to pull on surrounding structures. This traction can lead to several complications.
- Cataracts, or clouding of the lens.
- Glaucoma, or dangerously high pressure inside the eye. In one study of 72 patients with PHPV cataracts, glaucoma developed in 32% of cases (Pollard, 1997).
- Intraocular hemorrhage, which is bleeding inside the eye.
- Retinal detachment, where the retina pulls away from the back of the eye.
- Phthisis bulbi, where the eye shrinks and loses function.
Diagnosis and Testing
Diagnosis usually begins when a pediatrician or parent notices a white pupil or a smaller eye. The child will be referred to a pediatric ophthalmologist or retina specialist for a thorough examination. This exam is typically performed under sedation or anesthesia in very young children so the specialist can carefully evaluate the inside of the eye.
The specialist will look for the characteristic fibrovascular membrane behind the lens, assess the lens for cataracts, and examine the retina for any signs of detachment or other abnormalities.
Ultrasound of the eye is often the first imaging test used. It can reveal the persistent tissue inside the eye, measure the size of the eye, and help rule out other conditions. Ultrasound does not use radiation, making it safe for infants.
In some cases, magnetic resonance imaging (MRI) may be ordered. MRI provides detailed images and is especially helpful for distinguishing PHPV from retinoblastoma. Unlike retinoblastoma, PHPV does not contain calcium deposits, which is an important difference seen on imaging.
Because both PHPV and retinoblastoma can cause a white pupil in infants, ruling out cancer is a top priority. PHPV has been described as a benign mimic of retinoblastoma. The combination of a smaller eye, absence of calcification on imaging, and the characteristic appearance of the fibrovascular membrane helps specialists distinguish between the two conditions. In uncertain cases, close monitoring and additional imaging are used to confirm the diagnosis.
Treatment Options
The primary goals of treating PHPV are to prevent complications, preserve or improve vision when possible, and maintain the cosmetic appearance of the eye. Treatment decisions depend on the type of PHPV, the severity of the condition, and whether complications have already developed. Early surgical intervention gives the best chance for a positive outcome.
When the condition is limited to the front of the eye, surgery may involve several steps. The clouded lens is removed through a procedure called lensectomy or phacoemulsification (using ultrasound energy to break up the lens). The fibrovascular membrane behind the lens is carefully treated, sometimes using underwater electric coagulation to seal abnormal blood vessels. An anterior vitrectomy (removal of the gel from the front part of the eye) clears remaining tissue. In some cases, an intraocular lens (IOL) is implanted to replace the removed natural lens.
Children with purely anterior PHPV have the best visual outcomes. In one study, approximately 17% of treated eyes achieved vision of 20/100 or better, and successful visual results occurred only in eyes with a purely anterior presentation (Karr and Scott, 1986).
When the back of the eye is involved, surgery is more complex. The approach typically includes lensectomy combined with a posterior vitrectomy (surgical removal of the gel from the back of the eye). The surgeon carefully dissects the persistent stalk of tissue that extends from behind the lens to the retina. Retinal laser photocoagulation (thermal laser treatment) may be applied to seal areas of abnormal tissue or prevent bleeding. In some cases, silicone oil is placed inside the eye to hold the retina in position after surgery.
Modern vitreoretinal surgical techniques have improved outcomes for combined PHPV. In one study using updated methods, 71% of treated eyes achieved vision of 20/300 or better, and 57% reached 20/100 or better (recent clinical series). Smaller-gauge surgical instruments, such as the 23-gauge vitrectomy system, offer advantages including less tissue disruption and reduced need for sutures.
Surgery alone is not enough to achieve the best possible vision. Because PHPV usually affects only one eye, the brain may favor the healthy eye and ignore signals from the treated eye. This is called amblyopia, sometimes known as lazy eye. Treating amblyopia is a critical part of care.
Amblyopia therapy typically involves patching the stronger eye for a set number of hours each day. This forces the brain to use the treated eye and strengthen its visual connections. Contact lens fitting may also be needed if an intraocular lens was not placed during surgery. Studies have shown significant improvement in vision following surgery combined with three to 48 months of amblyopia treatment.
What to Expect
Recovery from PHPV surgery requires close follow-up with a retina specialist. Your child will need frequent eye exams in the weeks and months after surgery to monitor healing, check eye pressure, and watch for complications such as bleeding or retinal detachment. Eye drops will be prescribed to reduce inflammation and prevent infection.
Parents should expect that their child may need to wear a contact lens or glasses after surgery. Proper optical correction is essential for visual development, especially in infants and toddlers whose visual systems are still maturing.
Children with PHPV need ongoing eye care throughout childhood and into adulthood. Even after successful surgery, the risk of glaucoma, retinal detachment, and other complications remains. Regular eye pressure checks and retinal examinations are important for catching problems early.
Visual development should be tracked at each visit. If amblyopia therapy is underway, the specialist will adjust the patching schedule based on how the child's vision is progressing.
Visual outcomes depend heavily on the type and severity of PHPV. Children with anterior PHPV generally have better results than those with posterior or combined involvement. Even with the best treatment, the affected eye may not achieve the same level of vision as the healthy eye. However, preserving some useful vision in the affected eye provides important benefits, including depth perception and a wider visual field. When useful vision cannot be achieved, treatment still aims to maintain the eye's appearance and prevent painful complications.
Living With PHPV
Parents play a vital role in their child's visual outcome. Consistent adherence to amblyopia therapy, including patching and contact lens wear, is one of the most important things a parent can do. It can be challenging to keep a patch on a young child, but persistence makes a significant difference in results.
Working closely with a retina specialist and, when appropriate, a pediatric ophthalmologist ensures that your child receives coordinated care. Ask about local support groups or resources for families of children with visual impairments if additional help is needed.
Because PHPV most often affects only one eye, the healthy eye is especially important. Children with one affected eye should wear protective polycarbonate eyewear during sports and activities that carry a risk of eye injury. This simple precaution helps safeguard the child's primary source of vision.
A child with a visibly different eye may face questions or social challenges as they grow. Open, age-appropriate conversations about the condition can help your child develop confidence. If the affected eye becomes noticeably different in appearance, a retina specialist can discuss options for maintaining or improving cosmesis. Some families find it helpful to connect with other parents whose children have similar conditions.
When to See a Retina Specialist
Certain signs in a child with PHPV require urgent evaluation. Contact a retina specialist or go to the emergency room right away if you notice any of the following in your child.
- A new white or yellowish reflection in the pupil.
- Sudden redness, swelling, or pain in the affected eye.
- Your child suddenly refusing to open the affected eye or showing signs of discomfort.
- Any change in the appearance of the eye, such as a change in size or shape.
Early surgical intervention is necessary to prevent progressive changes inside the eye and to achieve the best visual results. Without treatment, PHPV can lead to recurrent bleeding inside the eye, secondary glaucoma, and, in severe cases, the need for enucleation (surgical removal of the eye). Keeping all scheduled follow-up appointments is essential, even when the eye appears to be doing well. Some complications develop gradually and can only be detected through a thorough examination.
Questions and Answers
No. PHPV is a benign developmental condition, not a cancer. However, it can look similar to retinoblastoma (a childhood eye cancer) because both can cause a white pupil in infants. This is why any white pupil must be evaluated urgently by a specialist. Imaging tests such as ultrasound and MRI help distinguish between the two conditions.
Some children do require additional procedures. The initial surgery addresses the abnormal tissue and lens changes, but complications such as glaucoma, retinal detachment, or recurrent membrane formation may develop over time and require further treatment. Each child's situation is different, and a retina specialist will create an individualized plan based on how the eye responds to initial treatment.
In the vast majority of cases, PHPV occurs sporadically and does not run in families. When only one eye is affected and there is no family history, the chance of a future child having the same condition is very low. In rare cases involving both eyes, a genetic component has been identified. If there is concern about hereditary factors, a retina specialist may recommend genetic counseling to assess the risk for future pregnancies.
Amblyopia therapy, including patching the stronger eye, is one of the most critical steps after surgery. Without it, the brain may continue to rely on the healthy eye and the treated eye's vision may not improve even if the surgery was technically successful. Studies have shown significant visual gains when patching and optical correction are started early and maintained consistently over months. Your child's specialist will guide you on the right amount of daily patching.
Without treatment, PHPV can lead to serious complications as the eye grows. These include recurrent bleeding inside the eye, worsening glaucoma, retinal detachment, and eventual shrinkage of the eye. In the most severe untreated cases, the eye may need to be surgically removed to prevent ongoing pain and infection. Early treatment aims to prevent these outcomes and preserve as much vision and eye structure as possible.