Conversation: The conversation between human and AI assistant.
[|Human|] Have NMO. Currently taking chemo. Had lost sight in left eye than in right. Right eye had improved for a while but just 2 days ago both eyes seemed to have some activity and now the right eye has gone to black. Have you heard of the vision getting worse before better?
[|AI|]  Hi, Thanks for writing in. Chemotherapy for Neuromyelitis optical can have different responses in different patients and variable responses in the same patient under different circumstances. It looks like the chemotherapy is showing variable response in your case. The improvement and worsening of vision depends on the recovery of the optic nerves and the surrounding swelling. When chemotherapy is given then there can be some initial swelling of optic nerve sheath and this can cause temporary worsening of vision. This can then improve slowly with time as the chemotherapy response gets better. Therefore, the initial worsening can be due to the swelling of the nerves and with continued treatment this will improve. However, since vision is an important area therefore please discuss in detail with your doctor. Please do not worry.