http://www.entlink.net/healthinfo/sinus/sinus_questions.cfm
American Academy of Otolaryngology--Head and Neck Surgery
This fact sheet provides answers to questions about sinuses, an inflammation of the membrane lining of any sinus, especially one of the paranasal sinuses. The fact sheet includes information on how common sinusitis is, what the signs and symptoms of acute sinusitis and chronic sinusitis are, how acute sinusitis is treated, how a physician determines the best treatment for acute or chronic sinusitis, and more.