I came across this before, I was considering High lefort 1 (well I still am just not at this moment). I asked about the possibility of blindness and my surgeon didn't say it was a risk. I'd like to see more sources on the topic. The fact that they could not find any signs of orbital injury, vascular problem, or abnormal fractures seems odd to me. I would think, if anything, it would be from a vascular injury.