Anophthalmia and microphthalmia develop during pregnancy and can occur alone, with other birth defects, or as part of a syndrome. Anophthalmia and microphthalmia often result in blindness or limited vision.

At a glance: Anophthalmia and Microphthalmia

• Signs: Being born without one or both eyes (anophthalmia) or with unusually small eyes (microphthalmia)

• Diagnosis: Prenatal tests, physical exam

• Treatment: Prosthetics, surgery

What are anophthalmia and microphthalmia?

Anophthalmia and microphthalmia are often used interchangeably. Microphthalmia is a disorder in which one or both eyes are abnormally small, while anophthalmia is the absence of one or both eyes. These rare disorders develop during pregnancy and can be associated with other birth defects.

What causes anophthalmia and microphthalmia?

Causes of these conditions may include genetic mutations and abnormal chromosomes. Researchers also believe that environmental factors, such as exposure to X-rays, chemicals, drugs, pesticides, toxins, radiation, or viruses, increase the risk of anophthalmia and microphthalmia, but research is not conclusive. Sometimes the cause in an individual patient cannot be determined.

What's the treatment for anophthalmia and microphthalmia?

There is no treatment for severe anophthalmia or microphthalmia that will create a new eye or restore vision. However, some less severe forms of microphthalmia may benefit from medical or surgical treatments. In almost all cases improvements to a child’s appearance are possible. Children can be fitted for a prosthetic (artificial) eye for cosmetic purposes and to promote socket growth. A newborn with anophthalmia or microphthalmia will need to visit several eye care professionals, including those who specialize in pediatrics, vitreoretinal disease, orbital and oculoplastic surgery, ophthalmic genetics, and prosthetic devices for the eye. Each specialist can provide information and possible treatments resulting in the best care for the child and family. The specialist in prosthetic diseases for the eye will make conformers, plastic structures that help support the face and encourage the eye socket to grow. As the face develops, new conformers will need to be made. A child with anophthalmia may also need to use expanders in addition to conformers to further enlarge the eye socket. Once the face is fully developed, prosthetic eyes can be made and placed. Prosthetic eyes will not restore vision.

How do conformers and prosthetic eyes look?

A painted prosthesis that looks like a normal eye is usually fitted between ages one and two. Until then, clear conformers are used. When the conformers are in place the eye socket will look black. These conformers are not painted to look like a normal eye because they are changed too frequently. Every few weeks a child will progress to a larger size conformer until about two years of age. If a child needs to wear conformers after age two, the conformers will be painted like a regular prosthesis, giving the appearance of a normal but smaller eye. The average child will need three to four new painted prostheses before the age of 10.

How is microphthalmia managed if there is residual vision in the eye?

Children with microphthalmia may have some residual vision (limited sight). In these cases, the good eye can be patched to strengthen vision in the microphthalmic eye. A prosthesis can be made to cap the microphthalmic eye to help with cosmetic appearance, while preserving the remaining sight.

Researchers estimate that about 1 in every 5,200 babies is born with anophthalmia/microphthalmia in the United States.

The causes of anophthalmia and microphthalmia among most infants are unknown. Some babies have anophthalmia or microphthalmia because of a change in their genes or chromosomes. Anophthalmia and microphthalmia can also be caused by taking certain medicines, like isotretinoin (Accutane®) or thalidomide, during pregnancy. These medicines can lead to a pattern of birth defects, which can include anophthalmia or microphthalmia. These defects might also be caused by a combination of genes and other factors, such as the things the mother comes in contact with in the environment or what the mother eats or drinks, or certain medicines she uses during pregnancy.

Like many families of children with a birth defect, CDC wants to find out what causes them. Understanding the factors that are more common among babies with a birth defect will help us learn more about the causes. CDC funds the Centers for Birth Defects Research and Prevention, which collaborate on large studies such as the National Birth Defects Prevention Study (NBDPS; births 1997-2011) and the Birth Defects Study To Evaluate Pregnancy exposureS (BD-STEPS; began with births in 2014), to understand the causes of and risks for birth defects, including anophthalmia and microphthalmia.

CDC continues to study birth defects, such as anophthalmia and microphthalmia, and how to prevent them. If you are pregnant or thinking about becoming pregnant, talk with your doctor about ways to increase your chances of having a healthy baby.

Anophthalmia and microphthalmia can either be diagnosed during pregnancy or after birth. During pregnancy, doctors can often identify anophthalmia and microphthalmia through an ultrasound or a CT scan (special x-ray test) and sometimes with certain genetic testing. After birth, a doctor can identify anophthalmia and microphthalmia by examining the baby. A doctor will also perform a thorough physical exam to look for any other birth defects that may be present.

There is no treatment available that will create a new eye or that will restore complete vision for those affected by anophthalmia or microphthalmia. A baby born with one of these conditions should be seen by a team of special eye doctors:

• An ophthalmologist, a doctor specially trained to care for eyes
• An ocularist, a healthcare provider who is specially trained in making and fitting prosthetic eyes
• An oculoplastic surgeon, a doctor who specializes in surgery for the eye and eye socket

The eye sockets are critical for a baby’s face to grow and develop properly. If a baby has one of these conditions, the bones that shape the eye socket may not grow properly. Babies can be fitted with a plastic structure called a conformer that can help the eye socket and bones to grow properly. As babies get older, these devices will need to be enlarged to help expand the eye socket. Also, as children age, they can be fitted for an artificial eye.

A team of eye specialists should frequently monitor children with these conditions early in life. If other conditions arise, like a cataract or detached retina, children might need surgery to repair these other conditions. If anophthalmia or microphthalmia affects only one eye, the ophthalmologist can suggest ways to protect and preserve sight in the healthy eye. Depending on the severity of anophthalmia and microphthalmia, children might need surgery. It is important to talk to their team of eye specialists to determine the best plan of action.

Babies born with these conditions can often benefit from early intervention and therapy to help their development and mobility.