The ear consists of three main parts: outer, middle, and inner ear. The outer ear includes the auricle and ear canal, which naturally produces earwax. The middle ear contains three ossicles that transmit sound vibrations. The inner ear contains the cochlea for hearing and the vestibular system for balance
Cochlear implant provides sound perception for moderate-to-profound hearing loss. Implant bypasses acoustic hearing through electrical stimulation of auditory nerve. Device consists of external processor and internal implant with electrodes
Earwax is a waxy substance secreted in the ear canal. Contains cerumen, sebum, fatty acids, alcohols, squalene and cholesterol. Two types exist: wet (brown, viscous) and dry (gray, flaky). Wet type is dominant, dry type is recessive
Earlobe is lower portion of outer ear made of tough connective tissues. Average 2 centimeters long, elongates slightly with age. Contains many nerve endings and may be erogenous zone. Develops from mesenchymal cells through cascade induction
Middle ear contains three ossicles: malleus, incus, and stapes. Hollow tympanic cavity surrounded by temporal bone. Auditory tube connects middle ear to nasal cavity. Eustachian tube equalizes pressure between middle ear and throat
Eustachian tube connects nasopharynx to middle ear, measuring 35mm long. Normally collapsed, opens during swallowing and pressure changes. Contains bony (12mm) and cartilaginous (24mm) parts. Four muscles control tube opening: levator veli palatini, salpingopharyngeus, tensor tympani, tensor veli palatini