Brief Answer:
Trauma is a rare cause for congenital opticatrophy

Detailed Answer:
Hello
Welcome to Health care Magic.

I am Dr. DADAPEER K, an ophthalmologist and I answer health problems related to eye.

It seems from the history that your 6 year old is having nystagmus, optic atrophy and congenital stationary night blindness.
Optic atrophy can be caused by various causes like hereditary, inflammation, injury, tumors....
Birth trauma is a relatively rare cause for unilateral optic atrophy. Bilateral optic atrophy is usually not caused by injury.
In this case it is unlikely to be a cause for symptoms of nystagmus and optic atrophy as congenital stationary blindness classically causes these symptoms. Congenital stationary night blindness is caused by mutation on X chromosome. In severe variety it leads to optic atrophy and nystagmus.

Hence in this particular case birth injury looks like unlikely cause for nystagmus, optic atrophy and congenital stationary blindness.

Hope the information is helpful to you.

Thank you
With regards

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