Coliboma of the optic nerve

The coloboma of the optic nerve disc is a consequence of incomplete closure of the choroidal fissure. This is a rare condition, usually sporadic, but there is also an autosomal dominant inheritance. Colonies of the optic nerve are equally often unilateral or bilateral and may be accompanied by systemic manifestations.

[1], [2], [3], [4], [5],

Symptoms of the optic nerve disc colonies

• Visual acuity is often reduced.
• A disk with a clearly delineated local silvery-white globular excavation, displaced downward so that the lower neuroretinal band is thinned or missing, and the normal tissue of the disc is enclosed in a small upper wedge.
• The disc can be enlarged.
• Retinal vessels are not changed.

The field of vision with an upper defect, which in combination with the type of disc can be mistaken for normotensive glaucoma.

Ophthalmic anomalies, including microphthalmos and colonies of the iris, ciliary body and choroid.

[6], [7], [8], [9]

Complications of the optic nerve disc colonies

• Serous macular retinal detachment.
• Progressive expansion of excavation with thinning of the neural band, despite normal intraocular pressure.
• Regmatogenic retinal detachment in the eyes with concomitant chorioretinal colobomas.

Systemic lesions

Systemic damage is quite numerous, so only the most important ones will be mentioned here.

1. Chromosomal abnormalities include Palau syndromes (trisomy 13), Edward (trisomy 18), "cat's eye" (trisomy 12).
2. CHARGE combines coloboma, heart defects, choanal Aire-sia, retarded growth, genital and ear anomalies.
3. Other syndromes: Meckel-Gruber, Goltz, Walker-Warburg, Goldenhar, Rubinstein-Taybi, Lenz microphthalmus and Dandv-Walker cyst.

[10], [11]