The mastoid process is a bony protuberance located at the back of the ear, one in each ear bilaterally. Clinically, the mastoid process usually begins to develop at the age of two years, and by the time a child reaches the age of six years, the mastoid process has basically developed. The mastoid is connected to the tympanic cavity through the tympanic sinus. Below the mastoid, there is a stalk, which contains the location of the facial nerve out of the skull, behind the mastoid there is a sigmoid sinus, which can be accessed internally to the tip of the rock, and in front of the mastoid is the location of the external auditory canal. If there is acute otitis externa, it can also cause swelling of the posterior ear canal and the mastoid region, which is manifested by lymph node swelling and pain, pressure and other related changes in the mastoid region, and the mastoid can reach the position of the temporal scales above the mastoid. Clinically, the mastoid process is a very important anatomical landmark, and the mastoid process is a very important surgical access location for otitis media surgery. For some patients with low immunity, mastoiditis of the middle ear can occur, and once the lesion continues to aggravate, it can lead to the formation of subperiosteal abscesses of the mastoid process and other related diseases.