Iritis is one of the most common cause for blindness, but this blindness evitable. Iris is the circular around pupil, at the front part of eyes. Iritis is usually caused by traumatic or non-traumatic reasons. Blunt trauma to eyes can cause acute traumatic inflammation of iritis. As to non-traumatic causes, iritis is usually connected with some conditions, for example reiter syndrome, inflammatory bowel disease, infection with herpes simplex and so on. It might give you the pain in eye or brow Region, sensitivity to light which increase the pain, redness of eyes, weird shaped pupil, blurry vision and headache. To prevent iritis developing to blindness, you only need to take some timely and simple treatment. Take medication such as eye drops, pills to speed up the healing and decrease the pain. Visit your oculist regularly to ensure the healing as necessary follow-up steps. You also need to note wear sunglasses when you need to go to bright circumstances. Don't worry too much. As long as you take medication exactly the oculist prescribed to you, protect your eyes from glare and bright light, it should be ok for you.