Yes they can, assuming they know you and you aren't asking for a narcotic. My doctors usually ask me to check my blood pressure during the video chat so they can see. I also had a heart monitor sent directly to me and the technician was on a video chat to tell me how to hook it up.
Eye doctors wouldn't be able to treat you unless it's an eye infection or something they can see, visually.
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I never give you my number, I only give you my situation.
Beatles