Persistent Hyperplastic Primary Vitreous PHPV Definition

Eye Floaters No More

Cure Eye Floaters Naturally

Get Instant Access

Persistence of the embryonic primary vitreous (hyaloid arterial system including the posterior tunica vasculosa lentis).

Epidemiology: This developmental anomaly is also very rare.

Symptoms and findings: Usually the disorder is unilateral.

Anterior variant of PHPV. With this more frequent variant, a white pupil (leukocoria or amaurotic cat's eye) typically will be discovered shortly after birth. This is caused by the whitish plate of connective tissue posterior to the lens. Depending on the severity, it will be accompanied by more or less severe changes in the lens leading to more or less severely impaired vision. In extreme cases, the lens resembles an opacified membrane (membranous cataract). In rare cases, fatty tissue will develop (lipomatous pseudophakia), and even more rarely cartilage will develop in the lens. Retrolenticular scarring draws the ciliary processes toward the center, and they will be visible in the pupil. Growth of the eye is retarded. This results in microphthalmos unless drainage of the aqueous humor is also impaired, in which case buphthalmos (hydrophthalmos) will be present.

Posterior variant of PHPV. Retinal detachment and retinal dysplasia can occur where primarily posterior embryonic structures persist. The whitish plate of connective tissue will only be visible where anterior changes associated with persistent hyperplastic primary vitreous are also present. The reduction in visual acuity will vary depending on the severity of the retinal changes.

Diagnostic considerations: A definitive diagnosis is usually possible on the basis of the characteristic clinical picture (see symptoms and findings) and additional ultrasound studies (when the posterior segment is obscured by lens opacities).

Differential diagnosis: Other causes of leukocoria (Table 11.1) should be excluded. Retinoblastoma, the most important differential diagnosis, can usually be excluded on the basis of ultrasound or CT studies. In the presence of a retinoblastoma, these studies will reveal an intraocular mass with calcifications. In contrast to PHPV, microphthalmos will not be present.

H Leukocoria should be regarded as a retinoblastoma until proven otherwise.

Treatment: The disorder is not usually treated as neither conservative therapy nor surgery can improve visual acuity. Surgery is indicated only where complications such as progressive collapse of the anterior chamber, secondary increase in intraocular pressure, vitreous hemorrhage, and retinal detachment are present or imminent. The only goal is to save the eye and maintain existing visual acuity.

Table 11.1 Differential diagnosis of leukocoria

Possible causes

Differential criteria

Congenital cataract (4-8:20 000)

Early infancy, unilateral or bilateral, normal globe size.

Retinoblastoma (1 : 20 000)

Infancy, normal globe size, unilateral (two-thirds) or bilateral (one-third), calcifications in tumor.

Retinopathy of prematurity grade V(1: 20 000)

Early infancy, usually bilateral, no microphthalmos, preterm birth with oxygen therapy.

Exudative retinitis (Coats' disease)

Childhood, unilateral.

Persistent hyperplastic primary vitreous

Usually unilateral, usually microphthalmos, connatal, centrally displaced ciliary processes.

Tumors

Astrocytoma, medulloepithelioma.

Exudative retinal detachment

In toxocariasis, angiomatosis retinae (von Hippel-Lindau tumor), diffuse choroidal hemangioma.

Other causes

Norrie's disease, incontinentia pigmenti (Bloch-Sulzberger disease), juvenile retinoschisis, retinal dysplasia, vitreous abscess, myelinized nerve fibers, coloboma of the optic disk (morning glory disk), foreign bodies in the vitreous chamber.

Clinical course and prognosis: The clinical course and prognosis depend primarily on the severity of the disorder. However, adequate surgical intervention can often save the eye and stabilize visual acuity even if at a very low level.

Was this article helpful?

0 0
Stretch Marks

Stretch Marks

Stretch Marks Prevention and Treatment. Learn What Exactly Are Stretch Marks And How Can They Be Treated. MP3 Audio included for your PC or IPod.

Get My Free Ebook and Audio


Post a comment