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Congenital Eye Abnormalities


Simeon A. Boyadjiev Boyd

, MD, University of California, Davis

Reviewed/Revised Sep 2022
Topic Resources

Eyes can be absent, deformed, or incompletely developed at birth, often in conjunction with other congenital abnormalities and syndromes.

A clinical geneticist should evaluate affected patients even in cases of apparent isolated congenital anomaly.

Chromosomal microarray analysis Diagnosis Chromosomal abnormalities cause various disorders. Abnormalities that affect autosomes (the 22 paired chromosomes that are alike in males and females) are more common than those that affect... read more , specific gene tests, or broader gene panel tests should be considered in the evaluation of patients with congenital craniofacial abnormalities. If the results of these tests are nondiagnostic, whole exome sequencing analysis is recommended.

Structural birth defects of the eye are treated surgically using various surgical techniques.


Hypertelorism is widely spaced eyes, as determined by increased interpupillary distance, and can occur in several congenital syndromes, including frontonasal dysplasia (with midline facial cleft, and brain abnormalities), craniofrontonasal dysplasia (with craniosynostosis Craniosynostosis Craniosynostosis is premature fusion of one or more calvarial sutures. (See also Introduction to Congenital Craniofacial and Musculoskeletal Disorders and Overview of Congenital Craniofacial... read more Craniosynostosis ), and Aarskog syndrome (with limb and genital anomalies).



Coloboma is a gap in the structure of the eye that may affect the eyelid, iris, retina, or optic nerve of one or both eyes. Coloboma of the eyelid is frequently associated with epibulbar dermoid cysts and is common in Treacher Collins syndrome, Nager syndrome, and Goldenhar syndrome. Coloboma of the iris raises the possibility of CHARGE association (coloboma, heart defects, atresia of the choanae, retardation of mental and/or physical development, genital hypoplasia, and ear abnormalities), cat eye syndrome, Kabuki syndrome, or Aicardi syndrome.


Causes of microphthalmia include prenatal exposure to teratogens, alcohol, and infections (eg, TORCH [ toxoplasmosis Toxoplasmosis Toxoplasmosis is infection with Toxoplasma gondii. Symptoms range from none to benign lymphadenopathy, a mononucleosis-like illness, to life-threatening central nervous system (CNS) disease... read more Toxoplasmosis , other pathogens, rubella Congenital Rubella Congenital rubella is a viral infection acquired from the mother during pregnancy. Signs are multiple congenital anomalies that can result in fetal death. Diagnosis is by serology and viral... read more , cytomegalovirus Congenital and Perinatal Cytomegalovirus Infection (CMV) Cytomegalovirus infection may be acquired prenatally or perinatally and is the most common congenital viral infection. Signs at birth, if present, are intrauterine growth restriction, prematurity... read more Congenital and Perinatal Cytomegalovirus Infection (CMV) , and herpes simplex Neonatal Herpes Simplex Virus (HSV) Infection Neonatal herpes simplex virus infection is usually transmitted during delivery. A typical sign is vesicular eruption, which may be accompanied by or progress to disseminated disease. Diagnosis... read more Neonatal Herpes Simplex Virus (HSV) Infection ]), and numerous chromosomal or genetic disorders, some of which are suggested by other clinical features. Growth and developmental delays are frequently present in microphthalmia that is caused by a chromosomal disorder. Facial asymmetry suggests Goldenhar syndrome or Treacher Collins syndrome, hand abnormalities suggest trisomy 13 Trisomy 13 Trisomy 13 is caused by an extra chromosome 13 and causes abnormal forebrain, midface, and eye development; severe intellectual disability; heart defects; and small birth size. Diagnosis is... read more Trisomy 13 , oculo-dental-digital syndrome, or fetal alcohol syndrome Fetal Alcohol Syndrome Alcohol exposure in utero increases the risk of spontaneous abortion, decreases birth weight, and can cause fetal alcohol syndrome, a constellation of variable physical and cognitive abnormalities... read more , and genital abnormalities may suggest chromosomal defects, Fraser syndrome, or CHARGE association (coloboma, heart defects, atresia of the choanae, retardation of mental and/or physical development, genital hypoplasia, and ear abnormalities).


Anophthalmia is complete absence of the eye globe and occurs in > 50 genetic syndromes caused by chromosomal anomalies or mutations in one of several genes (eg, SOX2, OTX2, BMP4). When skin covers the orbit, the anomaly is called cryptophthalmos, which suggests Fraser syndrome, Nager syndrome, or ophthalmia-mental retardation.

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