Just to add to the not very helpful PM, this is where I would have got my info in the first instance. Note that I stress in the PM that I'm a retired pilot, not a doctor.
File:Gray896.png - Wikipedia, the free encyclopedia
Edit: I've also told the story about removing a membrane from my baby son's lower lacrimal duct. (puncta) His eye was as right as rain in about 3 days, after weeks of doctors taking cultures etc., etc.
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