Fundus photograph in a 24-years-old male patient who complains of central vision loss. He had tuberculosis and it was treated with ethambutol until 3 months ago. Note the pale optic disc and a yellow ring around the disc suggestive of toxic optic neuropathy.

Fundus photograph in a 24-years-old male patient who complains of central vision loss. He had tuberculosis and it was treated with ethambutol until 3 months ago. Note the pale optic disc and a yellow ring around the disc suggestive of toxic optic neuropathy.