What Diseases Cause Small Eyes?

Small eyes or microphthalmia is an eye condition wherein eyeballs of eyes- one or both are unusually small. In some people affected by this condition, the affected eyeball may seem to be completely absent or missing. However, some eye tissue is generally still present even in such cases. This condition develops before birth.

A severe type of microphthalmia should be distinguished from anophthalmia, wherein no eyeball is formed at all. However, sometimes microphthalmia and anophthalmia both terms are used interchangeably. Vision loss may or may not occur in cases of microphthalmia. ⁽¹⁾

Sometimes, environmental factors like exposure to radiation, chemicals, toxins, viruses, etc. may increase the risk of microphthalmia, according to some studies. However, the evidence is not conclusive. ⁽⁵⁾

• In newborns, microphthalmia maybe sometimes related to fetal alcohol syndrome.
• It may also be associated with infections during pregnancy
• Herpes simplex virus, rubella, and CMV or cytomegalovirus may be associated with causing small eyes
• Chromosomal abnormalities may also lead to small eyes
• Patau syndrome (Trisomy 13). Triploid syndrome, 13q deletion syndrome, and Wolf-Hirschhorn syndrome may all be related to small eyes. ⁽²⁾
• Small eyes may also be caused due to specific medicines if consumed at the time of pregnancy. These medicines can create a host of other birth defects as well if taken at the time of pregnancy.

Some studies show that environmental factors like exposure to radiation, toxins, pesticides, drugs, chemicals, viruses, etc. can lead to small eyes. However, more studies need to be conducted to establish this theory.

Small eyes may produce the following signs and symptoms- ⁽⁴⁾

• Abnormally small one or both eyeballs (also known as unilateral or bilateral microphthalmos)
• Eyes may be of different size
• The cornea may be abnormally small
• Iris may have some portion of the tissue missing, giving it a keyhole appearance
• The optic disc may be affected due to keyhole appearances of the iris
• Drooping upper eyelids in many cases, due to paralysis of the muscles controlling eyelids
• Varying degrees of visual problems
• Blindness in some cases
• There may be a delay in achieving some developmental milestones
• There may also be some degree of mental retardation
• There may also be some physical abnormalities, like facial and head malformations
• There may be a malformation of ears and teeth
• Hearing impairment may be present in some cases
• There may also be some skeletal deformities
• There may also be a deformity in toes and fingers
• There may also be reproductive and urinary complications ⁽⁴⁾

No such cure has been found for microphthalmia or small eyes that will produce a brand-new eye or rebuild vision. However, some forms of microphthalmia that are less severe may get some benefit from medical or surgical intervention.

• Improvements to a kid’s appearance are generally possible in most of the cases, rather almost all cases
• A prosthetic eye can be fitted for cosmetic purposes and it will also promote the growth of the socket
• An affected kid may need to visit several eye specialists in order to avail the best possible treatment
• Prosthetic eyes are fitted once the face is grown completely. However, prosthetic eyes will not help in rebuilding the vision
• If there is some residual vision or limited sight in a kid with microphthalmia, the good eye is patched, and the affected eye is strengthened for vision
• A prosthetic in such case is made such that it improves cosmetic appearance and preserves the remaining sight at the same time ⁽⁵⁾

Small eyes are caused due to genetic alterations or mutations and abnormal chromosomes. Environmental factors like exposure to radiation, chemicals, drugs, pesticides, viruses, etc. may increase the risk of microphthalmia, according to some researches. However, it is not yet confirmed. Sometimes, there is no known cause for this condition

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