If left untreated for a long period of time, maxillary sinusitis can turn into chronic maxillary sinusitis or the lesions can spread to the surrounding area, which can lead to serious complications such as periorbital cellulitis, subperiosteal abscess, intraorbital abscess, and retrobulbar optic neuritis. Maxillary sinusitis is an inflammatory disease of the sinuses due to infections, allergies, etc. Maxillary sinusitis has the highest incidence among sinusitis. As the sinuses are located close to the orbital area, when maxillary sinusitis is not treated in a timely manner, the secretions from the sinuses do not drain well and the body’s resistance decreases, which can lead to the spread of inflammatory lesions to the surrounding tissues, resulting in inflammation of the relevant parts. When the lesion spreads to the surrounding tissues, it mainly leads to diseases such as periorbital cellulitis, suborbital periosteal abscess, intraorbital abscess, retrobulbar optic neuritis and other diseases, which leads to aggravation of the infection and symptoms. People with maxillary sinusitis are advised to seek prompt medical attention for standardized treatment.