It is separated from the external ear by the tympanic membrane and from the internal ear by a thin bony partition that contains two small openings: the oval window and the round window.Įxtending across the middle ear and attached to it by ligaments are the three smallest bones in the body, the auditory ossicles, which are connected by synovial joints. The middle ear is a small, air-filled cavity in the petrous portion of the temporal bone that is lined by epithelium. The treatment for impacted cerumen is usually periodic ear irrigation or removal of wax with a blunt instrument by trained medical personnel. However, some people produce a large amount of cerumen, which can become impacted and can muffle incoming sounds. Cerumen usually dries up and falls out of the ear canal. Cerumen also prevents damage to the delicate skin of the external ear canal by water and insects. The combination of hairs and cerumen helps prevent dust and foreign objects from entering the ear. Near the exterior opening, the external auditory canal contains a few hairs and specialized sweat glands called ceruminous glands that secrete earwax or cerumen. The tympanic membrane may be examined directly by an otoscope, a viewing instrument that illuminates and magnifies the external auditory canal and tympanic membrane. It may be due to pressure from a cotton swab, trauma, or a middle ear infection, and usually heals within a month. Tearing of the tympanic membrane is called a perforated eardrum. Between the epithelial layers is connective tissue composed of collagen, elastic fibers, and fibroblasts. The tympanic membrane is covered by epidermis and lined by simple cuboidal epithelium. The tympanic membrane or ear drum is a thin, semitransparent partition between the external auditory canal and middle ear. The external auditory canal is a curved tube about 2.5 cm (1 in.) long that lies in the temporal bone and leads to the eardrum. Ligaments and muscles attach the auricle to the head. The rim of the auricle is the helix the inferior portion is the lobule. The auricle or pinna is a flap of elastic cartilage shaped like the flared end of a trumpet and covered by skin. The external (outer) ear consists of the auricle, external auditory canal, and eardrum (Figure 1 and 2). The internal ear contains the sensory organs for equilibrium (balance) and hearing. Structures within the middle ear amplify sound waves and transmit them to an appropriate portion of the internal ear. The middle ear is a chamber located within the petrous portion of the temporal bone. The external ear is the visible portion of the ear, and it collects and directs sound waves to the eardrum. The ear is divided into three anatomical regions: the external ear, the middle ear, and the internal ear (Figure 2). When should a hearing test be performed related to frequent infections or fluid ?.What can cause Conductive Hearing Loss ?.Treatment for chronic suppurative otitis media.Home remedies for a ruptured or perforated eardrum.Treatment of a ruptured or perforated eardrum.Diagnosis of a ruptured or perforated eardrum.
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