my cat was run over three weeks ago taking a bang at the front

Hello, my name isXXXXX and I have over 20 years of experience as a veterinarian. I'd like to help with your concerns about Iss and her head trauma leading to her loss of vision.

The good news is that her eyes themselves appear normal. That means that her inability to see is related to a loss of function in her brain. That can be due to bleeding in or on the surface of her brain leading to pressure on the part of the brain that controls vision. If the bleeding stops, and pressure is relieved before the neurons die, it is possible that connections can be re-established and her vision may come back in some capacity. Cats seem to have better healing abilities then many other species and so I am more optimistic for her chances of recovery then if she were a dog.

Ideally increasing oxygen levels to the brain by putting her in an oxygen chamber, and using medications to decrease pressure on the brain, like steroids, non-steroidal anti-inflammatories or a drug called mannitol if her cerebrospinal fluid pressure was high could have been done immediately after her accident. Those things can all aid in healing. At this point, 3 weeks later, all that can be done is to give her time to heal, keep her indoors to keep her safe and prevent further trauma, and provide excellent nutrition to aid in healing.

It is possible that she will regain some vision, though I would not expect it to be normal. Even if she doesn't though many cats that are blind adjust very well and lead very happy lives. If kept indoors and you don't change your furniture arrangement she will memorize where things are and you may not be able to tell by casual observation that she cannot see.

Best of luck with your girl, please let me know if you have any further questions.