<s>[INST] my daughter got hit in the forehead today with a large hard rubber ball and then complained that the only color she could see was purple. This dissipated after a few hours. I took her to the ER and they did a CT scan and everything came back fine (or negative). Any idea what this is? [/INST] Hi and welcome to HCm. Thanks for the query. This is not usual symptom of head injury and she should be admitted to hospital for opservation. She needs to do more detailed ophtalmologist examination too to verify was there damage of eye structures. in most cases it passes spontaneously nad there is no specific treatment. Wish you good health. Regards </s>