The sinusitis refers to the inflammation of the mucous membrane that covers the inside of the sinuses. The sinuses are bony cavities (in 4 pairs) located in the facial bones (see diagram). Each sinus communicates with the nasal cavity through small openings through which the mucus produced in the sinuses normally flows. Inflammation of the sinus lining, also known as rhinosinusitis, is usually caused by a viral or bacterial […]