A mucocoele is a chronic, cystic lesion of the paranasal sinuses, lined by pseudostratified or low columnar epithelium. There is background inflammation, with the cyst filled with mucus, exerting pressure on the boundaries of the sinus due to obstruction of the sinus ostium. The obstruction is caused by congenital anomalies, allergy, infection, trauma, neoplasms and sinus surgery. Surgery is necessary for a complete cure. The ultimate goal of surgical intervention involves in re-establishing the sinus drainage and obliteration of the cavity with complete resection of the sinus mucosal lining.