Here are some reliable sources that can provide more information on endoscopic sinus surgery.
National Institute of Allergy and Infectious Disease
This organization conducts
This website, maintained by the U.S. National Library of Medicine, contains information about sinusitis and its treatments.
The American Rhinologic Society St. Louis University Department of Otolaryngology
The American Rhinologic Society is the only professional organization that deals specifically with sinus surgery, both conventional and endoscopic. Their website features general information on sinus surgery as well as many consumer publications.
Southern California Nasal and Sinus Care Center
The technique of endoscopic sinus surgery is explained on this website.