My husband has glaucoma in his left eye. He has field vision loss, but also his lens prescription is changing rapidly, his eye is red, eyelid is swollen, & some loss of color vision. All only in his left eye. He went to a glaucoma specialist who ordered an MRI. What could he suspect is causing these symptoms. Please level with me, I want to be well informed in order to help my husband face whatever the diagnosis may be.