Prevalence:

• 1 in 20,000 births.

Ultrasound diagnosis:

• In microphthalmia there is decrease in the size of the eyeball and in anophtalmia there is absence of the eyeball, optic nerve and chiasma. Both can be unilateral or bilateral.

Associated abnormalities:

• Chromosomal defects, mainly trisomy 13, are found in >50% of cases.
• Genetic syndromes are found in >50% of cases. The most common are Goldenhar syndrome (sporadic; anophthalmia,  ear defects, facial cleft, facial macrosomia), Fraser syndrome (autosomal recessive; microphthalmia, facial cleft, tracheal atresia, bilateral renal agenesis, heart defects, syndactyly or polydactyly), Fryns syndrome (autosomal recessive; anophthalmia, facial cleft, micrognathia, ventriculomegaly, diaphragmatic hernia).

Investigations:

• Detailed ultrasound examination, including neurosonography.
• Invasive testing for karyotyping and array.
• Fetal brain MRI for diagnosis of abnormalities such as absence of the optic nerve.

Follow up:

• Standard follow-up in isolated cases. If there is an underlying syndrome antenatal care should be adjusted according to the risks of the condition.

Delivery:

• Standard obstetric care and delivery.

Prognosis:

• Isolated: good.
• Syndromic: very poor.

Recurrence:

• Isolated: no increased risk.
• Part of trisomy 13: 1%.
• Part of an autosomal recessive condition: 25%.