The ear is the most important sensory organ within the otolaryngology department and is divided into the outer ear, middle ear and inner ear. The auricle is the protruding part of the outer ear on the head and is concave and convex in front of the auricle. The cartilaginous segment accounts for the outer third of the external auditory canal and the bony segment accounts for the inner 2/3 of the external auditory canal. Although the tympanic membrane is located at the bottom of the external auditory canal, it is part of the middle ear, which is located on the inner side of the tympanic membrane and includes four parts: the tympanic cavity, the eustachian tube, the tympanic sinus and the mastoid process. The inner wall is both the outer wall of the inner ear and the central tympanic capsule, which has a posterior and inferior snail window, also called the round window, and a posterior and superior vestibular window, also called the oval window, which is closed by the stapedial pedicle. The outer wall is composed of bone and membrane, the bone is the lateral wall of the upper tympanic chamber, the membrane is the tympanic membrane, the tympanic membrane includes the relaxed and tense parts, the center of the tympanic membrane is the umbilicus, the anterior upper part is the short prominence of the hammer bone, the hammer pattern between the umbilicus and the short prominence is the reflection of the hammer bone stem; the lower part of the anterior wall is separated from the internal carotid artery by a very thin bone plate, the upper part of the anterior wall is the eustachian tube bullae, which is the communication port between the tympanic chamber and the nasopharynx; the upper part of the posterior wall has the entrance of the tympanic sinus, which also belongs to the The conus bulge is a bony structure in the posterior wall of the tympanic cavity, to which the stapedius muscle is attached. The conus bulge is located within the posterior tympanic cavity, which is the cavity of the tympanic cavity behind the posterior edge of the tympanic membrane. The tympanic chamber houses a number of small structures, including the auditory bones, muscles, and nerves. The auditory bones include the hamate, anvil, and stapes; the tympanic chamber muscles include the tympanic tensor muscle, whose tendon bypasses the sphenoid process and ends just below the neck of the hamate; the stapedius muscle, which begins in the cone bulge of the posterior wall of the tympanic chamber and whose tendon descends forward to end just behind the neck of the stapes; and the tympanic cord nerve, which is a branch of the facial nerve that branches off at the point of entry into the stem mammary foramen and enters the tympanic chamber. After understanding the structure of the tympanic chamber, the tympanic chamber can be divided into the upper, middle and lower tympanic chambers by the upper and lower edges of the tympanic membrane, and the eustachian tube is the tube that communicates between the tympanic chamber and the nasopharynx. The pharyngeal opening of the eustachian tube is 2.5cm lower than the drum opening in adults, while the eustachian tube is close to the horizontal in children, and the distance between the tubes is short and the inner diameter is wide, so it is easier for the infection in the nasopharynx of children to expand into the ear. The mastoid air chamber, which is the last part of the middle ear, can be divided into four types according to the degree of pneumatization: pneumatized mastoid, with a large air chamber and thin bone septum, which accounts for about 80% of this type; plate-blocked mastoid, with poorly pneumatized mastoid and small and numerous air chambers; sclerotic mastoid with unpneumatized mastoid and dense bone; and mixed mastoid, with any two of the above three types existing at the same time or all three types existing at the same time. The vestibule is located between the cochlea and the semicircular canal and is slightly oval in shape. The bony semicircular canal is located in the posterior and superior part of the vestibule and is three bow-shaped curved bony canals at right angles to each other, which are called the external semicircular canal and the horizontal semicircular canal, depending on their orientation. The cochlea is located in front of the vestibule and resembles a snail’s shell, mainly consisting of the cochlear shaft in the center, the bone spiral plate extending from the cochlear shaft and the surrounding cochlear canal, which is 2 and 1/2 to 2 and 3/4 weeks around the cochlear shaft, and the cochlear canal has three lumens, the vestibular step above, to the The vestibular step starts from the vestibule, and the lower one is the tympanic step, which is closed by the membrane of the cochlear window, and the vestibular step and the tympanic step are connected at the top of the cochlea by the cochlear foramen. The membranous vagus is a membranous part located in the bony vagus. The membrane vagus is filled with exolymphatic fluid between the membrane vagus and the bony vagus, and its chemical composition is similar to that of cerebrospinal fluid, which is connected to the subarachnoid space through the cochlear duct. The membrane vagus is composed of membrane ducts and membrane sacs, including the ellipsoid bursa, balloon bursa, membrane cochlear duct and membrane semicircular duct. The entire membrane vagus is filled with endolymphatic fluid, the chemical composition of which is close to intracellular fluid. The membrane semicircular canal is attached to the lateral wall of the bony semicircular canal, and is connected to the ellipsoid bursa by five pores; the membrane potbelly has a potbelly ridge, which is a balance receptor; the membrane snail canal is located between the vestibular order and the tympanic order, and is triangular in cross-section; the upper wall is the vestibular membrane, the lateral wall is the spiral ligament, and the lower wall is the basilar membrane; the basilar membrane is spiral with the spiral plate and the bony snail canal, and its upper and lower arrangements The spiral apparatus is located on the basilar membrane and is also called the corti apparatus, which is an auditory receptor. The facial nerve is also an important structure in the anatomy of the middle and inner ear. It is the longest segment of the cranial nerve that travels within the bony canal, and within the temporal bone the facial nerve can be divided into the internal auditory canal segment, which starts at the base of the internal auditory meatus and ends at the base of the internal auditory canal, the vagus segment, which starts at the base of the internal auditory canal and reaches the geniculate ganglion forward, and the tympanic segment, also called the horizontal segment, which starts at the geniculate ganglion and goes slightly downward posteriorly, above the vestibular window and below the external semicircular canal to reach the posterior wall of the tympanic chamber The vertical segment starts at the level of the conus bulge and ends at the foramen magnum.