When I was at Mayo Clinic, one of the eye doctors put tape at the top of my mask to seal it. He did the same to his because he wore glasses. This prevents fogging up glasses (or eye exam equipment).

I'd suggest using paper tape for this because the skin around the eyes is very delicate and regular medical tape is a bitch to get off. They used medical tape, and I felt like it was ripping my lower eyelids off when I removed it!