Hi Mr. Naresh, Sorry for the visual handicap which resulted following head injury for your brother. Let me give you few possible reasons for the visual handicap: 1. An injury to the back of the head, which would have occured after a fall usually destroys or damages an area that coordinates signals between the brain and the eyes. In this case, the eyes could be perfectly normal, but the function in the brain allowing the eyes and brain to communicate would be damaged and no longer work. Causing loss of vision. You said that neurosurgeon ruled out brain injury, but this loss of coordination can occur at a later date. 2.Optic nerve entrapment could have happened, the optic nerve is pressed by the broken skull bones, causing irregularities in vision. 3.Head Trauma can even damage important eye structures like the retina and optic nerve that are critical to eyesight. Most important thing to note is that there is crossing of fibers that carry visual signals in brain, so an injury to right side of brain causes loss of vision in left eye. Hope I Have cleared your doubts. Any Further Quires please feel free to contact.