Optic nerve coloboma
A 20 years old female presented for a routine eye examination. Her best-corrected visual acuity (BCVA) was OU - 20/20 Snellen chart. Fundoscopy of the right eye revealed a massive optic disc coloboma with no other associated abnormalities. Fundoscopy of the left eye revealed a normal eye fundus.
Optic nerve coloboma is a congenital condition caused by incomplete closure of embryonic fissure. It usually occurs bilaterally, autosomal dominantly inherited, or sporadic cases. Serous macular detachment and visual field loss can be frequently observed in this condition. It can also be associated with other colobomas (lens, ciliary body and choroid), microphthalmia, retinal dysplasia, or can be part of systemic anomalies like Aicardi syndrome, Meckel syndrome and CHARGE association, with poor visual prognosis. Subjects with isolated optic nerve coloboma, with no other associated abnormalities, like this case, can have an excellent visual prognosis.