Yoga Eye Pillow

How exactly to put pressure on your eyes with a feeling of herbs eye pillows Yoga helps to relax, etc.? Why the right pressure for the retina, etc.? This already sounds like a stupid question, but if someone could guide me through what Id appreceate!

I am an ophthalmologist .. and I do not really believe these things work ...

may be a kind of placebo effect or something ..!!!

if you know better please let me know ...