Peters anomaly is a rare condition that affects the eyes. It develops before birth due to a genetic mutation. People born with this condition experience vision problems due to cloudy patches on the cornea, iris, and lens of the eye.
There are treatments to mitigate symptoms, but there is no cure for this condition.
The Effects of Peters Anomaly
Peters anomaly is a rare congenital eye condition. The condition causes thinning of the cornea and a clouding of the cornea's surface. It also affects the connection between the cornea and the iris (the colored part of the eye). The condition causes blurred vision and difficulty seeing. Cataracts, clouding of the lens of the eye, may also be associated with Peters anomaly.
Peters anomaly is extremely rare. It's estimated that one in 1000 people in the United States will have Peters anomaly in the eye. It's typically diagnosed during infancy or early childhood. Doctors or parents will notice the characteristic clouding in the eyes or notice signs of decreased vision in the affected child.
The condition is named after Dr. Alfred Peters, a German ophthalmologist. Dr. Peters was the first to describe the condition in modern medical literature.
Peters Anomaly Symptoms
Peters anomaly affects the cornea, which is the clear membrane that covers the front of the eye. The cornea becomes clouded, which obstructs vision. This clouding may be further complicated by defects that cause the cornea to be improperly connected to the iris. This can lead to swelling and a further increase in cloudiness and vision issues.
Defective connections between the cornea and iris vary in severity. In some cases, the two membranes are connected by thin filaments. In other cases, the connections form thicker bands. In the most severe cases, they resemble sheets and create significant visual obstructions.
Experts have identified two types of Peters anomaly. In the case of Type I, typically, only one eye is affected. The clouding is limited to the center of the cornea, leaving the peripheral cornea clear. It generally comes with a strong prognosis for vision.
Type II Peters anomaly affects both eyes. The lens of the eye is more likely to be compromised, as well as the cornea, leading to cataracts in addition to corneal clouding. Vision will be more severely compromised in these cases.
In rare cases, Peters anomaly is accompanied by additional physical symptoms, such as a cleft palate, unusually short stature, or developmental disabilities. This is known as Peters plus syndrome.
Glaucoma is a common complication of Peters anomaly. Glaucoma is a condition caused by increased pressure in the eye. This pressure may damage the optic nerve, leading to vision loss. In cases of Peters anomaly, signs of glaucoma are often present from birth, though it may also develop later in childhood.
Peters Anomaly Causes
The exact causes of Peters anomaly are unclear, but it appears to be a genetic disorder. Experts believe that it is related to mutations in several genes. These genetic anomalies may be inherited from one or both parents, or they could be spontaneous changes that occur during embryonic development.
When Peters anomaly is inherited, this occurs in an autosomal recessive pattern. If both parents carry the genetic trait, they can pass it along to their children. There is a 25% chance of the child from each pregnancy being born with Peters anomaly.
Peters Anomaly Treatment
There is no cure for Peters anomaly. Conditions caused by such genetic abnormalities are lifelong. The affected genes exist in every cell of the body, and they cannot be changed. There are treatments to mitigate the symptoms of Peters anomaly, though.
In mild cases where only one eye is involved, your doctor may suggest occlusion therapy. This involves covering the unaffected eye with a patch to encourage the affected eye to get stronger. This is typically prescribed to prevent individuals from developing amblyopia (wandering eye).
There are also surgical treatments for Peters anomaly, including:
Peripheral iridectomy: Doctors remove a portion of the iris. The goal is to create a clear visual axis and improve vision.
Penetrating keratoplasty and cataract removal: In this procedure, doctors replace all or part of the cornea with donor tissue. If there are cataracts affecting the lens of the eye, they can be removed at the same time.
Keratoprostheses: If keratoplasty fails, doctors can implant an artificial cornea.
Glaucoma surgery: There are a number of procedures to manage the effects of glaucoma. These procedures all work to control the pressure in the eye and prevent further damage. Your doctor may remove a section of the eye tissue or place a drainage device to allow better drainage of excess fluid in the eye, which is called the aqueous humor. They may also use a laser to destroy some of the structures that produce aqueous humor to reduce the amount of fluid in the eye.
If Peters anomaly is accompanied by the systemic symptoms associated with Peters plus syndrome, treatment will be based on symptoms. That may include physical, speech, or occupational therapy to manage physical or cognitive disabilities. Children may need supportive accommodations at school. Conditions such as cleft palate require surgical treatment.
Prognosis of Peters Anomaly
The effects of Peters anomaly vary. If the condition only affects one eye, vision problems may be manageable with adequate care and corrective lenses if appropriate. In more severe cases where both eyes are involved, vision may be compromised.
The surgical treatments for Peters anomaly can be helpful, but some people require multiple procedures over time, and there is no guarantee that any treatment will alleviate the most serious effects of Peters anomaly.
For people who have significant visual impairment due to Peters anomaly, it may be appropriate to seek accommodations designed to assist people with visual disabilities or blindness. Your doctor or a social worker can advise you about programs that will be helpful for you.