Congenital eye anomalies include eyes that are absent, deformed, or incompletely developed, often in conjunction with other congenital anomalies and syndromes.
(See also Overview of Congenital Craniofacial Anomalies.)
A clinical geneticist should evaluate affected patients even in cases of apparent isolated congenital anomaly.
Chromosomal microarray analysis, specific gene tests, or broader gene panel tests should be considered in the evaluation of patients with congenital craniofacial anomalies. If the results of these tests are nondiagnostic, whole exome sequencing analysis may be recommended.
Structural birth defects of the eye are treated surgically using various surgical techniques. Consultation with a pediatric ophthalmologist is important for children with these conditions.
Hypertelorism
Hypertelorism is widely spaced eyes, as determined by increased interpupillary distance, and can occur in numerous congenital syndromes, including frontonasal dysplasia (with midline facial cleft, and brain anomalies), craniofrontonasal dysplasia (with craniosynostosis), and Aarskog syndrome (with limb and genital anomalies).
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Hypotelorism
Hypotelorism is closely spaced eyes, as determined by decreased interpupillary distance. This anomaly should raise suspicion of holoprosencephaly (a midline brain abnormality).
Coloboma
Coloboma is a gap in the structure of the eye that may affect the eyelid, iris, retina, or optic nerve of 1 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, retarded growth and development, genital hypoplasia, and ear abnormalities), cat eye syndrome, Kabuki syndrome, or Aicardi syndrome.
Microphthalmia
Microphthalmia is a small eye globe, which may be unilateral or bilateral. Even when unilateral, mild anomalies (eg, microcornea, colobomas, congenital cataract) of the other eye are frequently present.
Microphthalmia causes sight-threatening complications such as angle-closure glaucoma, chorioretinal pathology (eg, uveal effusion), strabismus, and amblyopia.
Causes of microphthalmia include prenatal exposure to teratogens, alcohol, and infections (eg, TORCH [toxoplasmosis, other pathogens, rubella, cytomegalovirus, and herpes simplex]), 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 anomalies suggest trisomy 13, oculo-dental-digital syndrome, or fetal alcohol syndrome, and genital anomalies may suggest chromosomal defects, Fraser syndrome, or CHARGE association (coloboma, heart defects, atresia of the choanae, retarded growth and development, genital hypoplasia, and ear abnormalities).
Anophthalmia
Anophthalmia is complete absence of the eye globe. It occurs in > 50 genetic syndromes caused by chromosomal abnormalities or pathogenic variants 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 ocular disorders associated with intellectual disabilities.