Hello Welcome to health care magic. I reviewed your history. I can understand your concern. It seems from the history that your father has lost vision in one eye because of optic nerve injury in a accident. Unfortunately the direct damage to the optic nerve cannot be reversed. However if there is indirect pressure over the optic nerve it can be treated, hence you need yo consult your doctor for evaluation to find out the severity and nature of injury. Hence I advice you to consult your doctor for examination and treatment accordingly. Thank you