Hello KK,
I'm sorry to hear about your dog. Glaucoma is a terrible disease - I've learned a lot about it since ny son [age 4 1/2] was diagnosed with it in March of this year. He has been on as many as 5 different eye drops at one time and has had six eye surgeries that have not been successful in controlling the pressure. Just as I did not know children could get glaucoma [or be born with it] I did not know dogs could get it either. There are a number of eye drops and even oral medication for people with glaucoma, if the drops your vet has prescribed do not help you may want to ask him if any of the drops that are available for humans would help.
Good luck,
Silverleaf