Get Sinusitis Prevention with advanced chronic sinusitis treatment In Hyderabad. Sinusitis is an inflammation of the sinuses, usually caused by infection. Long Description: If you have nasal congestion, facial pressure, cough, and thick nasal discharge, you may have rhinosinusitis, commonly known as sinusitis. Your sinuses are hollow cavities in your cheek bones, around your eyes and behind your nose. They contain mucus, which helps to warm, moisturize and filter the air you breathe. When mucus usually prevents anything from drying out, infection can occur.