@Hummingbird @Steadfast - Very interesting. My son had some kind of cross eye issue as a child. (I could look in my notes to see what it was called. He wore a patch for several months.) He also had a sudden onset of severe impact to his vision well after onset of SZ…I believe it was either due to repeated severe catatonia or possibly to having received too much ECT (the ECT was necessary and effective but due to uncoordinated care over which we had no control, after months of receiving ECT, it became apparent that it causing other problems and had to be stopped). He was seen by a vision specialist. This latter problem eventually resolved while on Clozapine. I think his brain just needed to heal and the Clozapine helped with that. His additional symptoms at that time when he had trouble seeing (could barely sign his name and could not read his phone) were indicative of a condition called Formal Thought Disorder. You can read about that here: Thought Disorder | Johns Hopkins Psychiatry Guide
Also, my dad was born partially blind and had some kind of major depression or other mental health issue, including possible mania, as an adult and in later life.