Our 11 year old Maltese called Pop has cataracts, and I am thinking about an operation to remove them, but what is the success rate? I'm worried that he will start bumping into furniture if he can't see.

A cataract affects the lens in a dog's eye, causing it to become cloudy, so the eye develops a whitish appearance. Cataracts are the result of a degenerative process, which is most common in older dogs, and can sometimes be linked with other underlying conditions, especially diabetes mellitus. This may need further investigation.

Success rates for cataract surgery itself, leading to an improvement in the dog's vision, are typically between 85 and 90%, but do bear in mind that this tells only part of the story.

There is a considerable amount of daily post-operative care required, which will extend over months, and a risk of serious complications, such as glaucoma, developing.

A number of other important factors have to considered as well, before cataract surgery is undertaken, including the possibility of other eye problems, such as damage to the retina at the back of the eye. Pop will need a general anaesthetic, and if he is overweight or has a chronic heart problem for example, the risk may not be worthwhile, especially in view of his age.

Dogs certainly do adapt much better to a loss of vision than we do, simply because they are far less reliant on their sense of sight. There are even cases on record of blind dogs being able to hunt successfully. Smell is very important in their world, and even if you do move the furniture around, Pop should be able to cope, especially as he still has some residual vision. If you decide that you want to investigate the surgical option further however, consider asking your vet to refer you to a specialist in veterinary ophthalmology.