THE EAR The ear is a major sense organ concerned with two important functions; a) Hearing b) Balance The ear provides an auditory input into the brain by detecting vibrations in the surrounding air and converting them into nerve impulses. These impulses are relayed to the brain where they are interpreted as sounds. The possession of two ears allows us the ability to sense direction. The role of the ear in balance is achieved by vestibular apparatus detecting changes in velocity and position of the body. Nerves relay this information to centres within the cerebellum of the brain. Root Combining form Meaning Acoust Audi Aur Auricul Cerumin Cochle Incud Labyrinth Malle Mast Myring Ot Salping Acoust/o Audi/o Aur/i, -aural Auricul/o cerumin/o Cochle/o Incud/o, -incudal Labyrinth/o Malle/o Mastoid/o Myring/o Ot/o Salping/o Staped/o, stapedi/o Tympan/o Vestibul/o Hear/hearing/sound Hear/hearing Ear Ear/pinna Cerumen / ear wax (cera - wax) Cochlea, snail (receptor for hearing in the inner ear) Incus bone or anvil Maze, twisted spiral shape Malleus bone or hammer Breast, nipple shaped Membrane Ear Eustachian or trumpet tube Stapedi Tympan Vestibul Stapes bone or stirrup Drum Entrance Activity 1 Build words which mean 1. The study of the anatomy and physiology of the ear __________________________ 2. Fungal infection/condition of the ear ______________________________________ 3. Excessive flow of pus from the ear________________________________________ 4. Instrument to view the ear THE EAR _________________________________________ Page 1 of 5 The ear can be divided into three areas, the external, middle and inner ear. Infection and inflammation (otitis) can occur in any of these areas. Terms used to describe the position of the inflammation are; Otitis externa – inflammation of the external ear Otitis media – inflammation of the middle ear Otitis interna – inflammation of the inner ear Infection commonly begins in the middle ear because it is connected to the nasopharynx by a short tube known as the Eustachian canal. This canal functions to equalize the pressure on either side of the eardrum but it also provides an entrance for microorganisms. Activity 2 Write the meaning of 1. Binaural __________________________________________________________ 2. Endaural __________________________________________________________ 3. Salpingitis __________________________________________________________ Viewing the ear canal and tympanic membrane is improved by using an aural speculum, a device which is inserted into the external ear before examining with an auriscope. The auriscope is used to examine the external ear canal and the ear membrane. Occasionally, the ear canal becomes blocked by excessive wax production by the cerumenous (wax) glands in its lining. This can be removed by washing the ear with warm water using an aural syringe. Activity 3 Build words which mean 1. Incision into the ear membrane _________________________________________ 2. Instrument used to cut the ear membrane __________________________________ 3. Middle ear infection 4. Reconstruction surgery of the tympanum __________________________________ 5. Removal of the stapes _________________________________________ _________________________________________ Sometimes the tympanic membrane is surgically punctured to assist the drainage of fluid from the middle ear (as in glue ear). Once an opening is made in the membrane, fluid drains through the Eustachian tube into the nasopharynx. A small plastic grommet can be fixed into the membrane and this assists drainage for an extended period. The grommet eventually falls out and the membrane heals. THE EAR Page 2 of 5 Activity 4 Build words which mean 1. Technique of recording the cochlea’s electrical activity ________________________ 2. Inflammation of the labyrinth 3. Removal of the tissue from the mastoid process _____________________________ _________________________________________ Within the middle ear are found the smallest bones in the body, the ear ossicles – they are the malleus, incus and stapes. Their function is to transmit vibrations from the tympanic membrane to the inner ear via the oval window. Behind the oval window is a fluid filled structure known as the cochlea, the organ of hearing. Within the cochlea are sensory hair cells, which respond to vibrations in the fluid by producing nerve impulses. The auditory area of the brain interprets these sounds and enables us to hear. Activity 5 Build words which mean 1. The science dealing with the study of hearing _______________________________ 2. Instrument to measure hearing _________________________________________ 3. Chart/tracing of hearing ability _________________________________________ 4. The measurement of hearing _________________________________________ Abbreviations: AC Air conduction AD Auris dextra (right ear) AD Auris Dextra (right ear) AS Auris sinistra (left ear) AS Auris Sinister (left ear) Aud Audiology BC Bone conduction ENT Ear nose and throat ETF Eustachian tube function OE Otitis externa OM otitis media Oto Otology THE EAR Page 3 of 5 Conditions and Terms: deafness conductive glue ear Meniere's disease otalgia hearing impairment resulting from obstruction of sound waves accumulation of fluid in the middle ear, causing deafness disorder of inner ear characterised by recurrent vertigo, deafness and tinnitus pain in ear (earache) otorrhagia bleeding from the ear otorrhoea discharge from the ear tinnitus continuous ringing, buzzing noise in ear dizziness, sensation of feeling that the person or his surroundings are spinning vertigo Procedures: audiogram recording tracing of hearing (made with an audiometer) myringoplasty surgical repair of a perforation of the tympanic membrane myringotomy incision made into the eardrum ossiculoplasty repair of the ear bones otoplasty plastic surgery of the ear stapedectomy removal of the stapes, third ossicle of the ear surgical repair of the tympanic membrane when there are problems with disease such as infection or bone problems tympanoplasty THE EAR Page 4 of 5 Ear flap (pinna) Ear membrane Middle ear and ear drum -------------- ---------------- --------------- Section through the ear Write the appropriate combining form on the dotted lines – more than one component may relate to the same position. Auricul/o Ot/o THE EAR Cochle/o Salping/o Labyrinth/o Tympan/o Mastoid/o Vestibul/o Myring/o Page 5 of 5