Have Cat Questions? Ask a Cat Vet Online.
There is a high probability that if the eyes are continuously dilated that the cat no longer has vision.
You can put the cat in a dark room then shine a flashlight in the eyes, if the pupils remain dilated, there is a problem.
Neurological disese, or tumors affecting the optic chiasm are the top ruleouts.
A trip to your vet is warranted.