Jessica is a 32 y/old math teacher who presents to the ER with a friend for evaluation of sudden decrease of vision in the left eye. She denies any trauma or injury. It started this morning when she woke up and has progressively worsened over the past few hours. She had some blurring of her vision 1 month ago and thinks that may have been related to getting overheated since it improved when she was able to get in a cool air-conditioned environment. She has some pain if she tries to move her eye but none when she just rests. She is also unable to determine colors. She denies tearing or redness or exposure to any chemicals. Nothing has made it better or worse.