International guidelines
North America
Published by:American College of Radiology
Last published:2022
Published by:American Academy of Otolaryngology-Head and Neck Surgery
Last published:2013
Published by:American Academy of Neurology
Last published:2012 (re-affirmed 2023)
Rest of the world
Published by:International Head and Neck Scientific Group
Last published:2020
Published by:JAMA Facial Plastic Surgery
Last published:2019
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