Hi,
Cherry eye is a term used to describe the inflammation of the Harderian gland. The Harderian gland secrets lubricating fluid and lies underneath the third eyelid. Obviously removing this gland will remove the lubrication fluid too. Your vet is the only one who can tell you the likely outcome of removal in your dog but if the gland has been imflammed for sometime it seems unlikely that it is still lubricating properly, if at all. There are drops that can substitute it's function but you must be dedicated in administering them. Ask your vet to refer you to an eye specialist if you are unhappy with the way he is treating the condition. I hope this helps.