Optic Nerve Coloboma

Bilateral Optic Nerve Coloboma

  • Uncommon, unilateral or bilateral congenital condition caused by incomplete closure of the embryonic fissure.
  • May present as sporadic cases or autosomal dominantly inherited (bilateral).

Clinical features:

  • Visual field defects
  • Relative afferent pupillary defect (RAPD)
  • Signs:
    • Enlarged, sharply circumscribed, glistening white and deeply excavated optic disc which usually occurs inferiorly
    • May mimic glaucomatous cupping in mild cases
    • Can develop serous macular detachment
  • Other associated ocular findings may include:
    • Coloboma of the lens, ciliary body and choroid
    • Microphthalmos with orbital cyst
    • Persistent hyaloid artery
    • Retinal dysplasia
  • May also be part of systemic anomalies, including:
    • CHARGE association (coloboma, congenital heart disease, and choanal atresia, growth or development retardation with multiple anomalies). Trisomy 13.
    • Meckel's Syndrome (bilateral ocular disorders associated with multisystem developmenteal abnormalities).
    • Aicardi's Syndrome (bilateral ocular condition associated with disorder of cranial, choroidal-pigment epithelial and skeletal development.