This may mean limited vision, of total lack of vision.
Your cat may bump into furniture one objects for no apparent reason. It is also quite common for an elderly cal to have more problems with his eyesight in bright light and in darkness, and he may be reluctant to venture out at such times.
There is a variety of causes – from injury to hereditary diseases and conditions. As cats age, it is quite common for a bluish colour to appear in the eyes as the lens of the eye deteriorates.
What to do
Any cat showing symptoms of failing eyesight should be taken to a vet without delay.
Treatment This depends upon the cause, but many cases of total blindness are untreatable.