ear (ēr) the organ of hearing and of equilibrium, consisting of the external ear, the middle ear, and the internal ear.
ear
ear [ēr]
Blainville ears asymmetry of the ears.
Cagot ear one without a lower lobe.
cauliflower ear a partially deformed auricle due to injury and subsequent perichondritis.
diabetic ear mastoiditis complicating diabetes.
external ear the pinna and external meatus together.
glue ear a chronic condition marked by a collection of fluid of high viscosity in the middle ear, due to obstruction of the eustachian tube.
inner ear the labyrinth; the vestibule, cochlea, and semicircular canals together.
middle ear the cavity in the temporal bone comprising the tympanic cavity, auditory ossicles, and auditory tube.
outer ear external e.
| ear (îr) n. 1. The organ of hearing, responsible for maintaining equilibrium as well as sensing sound and divided into the external ear, the middle ear, and the inner ear. 2. The part of this organ that is externally visible. 3. The sense of hearing. |   cross section |
ear
Etymology: AS, eare
one of two organs of hearing and balance, consisting of the external, middle, and internal ear. The external ear includes the skin-covered cartilaginous auricle visible on either side of the head and the part of the external auditory canal outside the skull. Together they form a funnel that directs sound waves toward the eardrum, or tympanic membrane, which marks the boundary between the external ear and the air-filled middle ear. The middle ear contains three very small bones, the malleus, incus, and stapes, which transmit vibrations caused by sound waves reaching the tympanic membrane to the oval window of the inner ear. The leverage of the ossicles, or middle-ear bones, increases the intensity of sound vibrations by more than 25 dB. Because the inner ear is filled with fluid, the increased intensity helps compensate for the loss of signal normally caused by sound-wave reflection of the fluid. The inner ear contains two separate organs: the vestibular apparatus, which provides the sense of balance, and the cochlea, with the organ of Corti, which receives vibrations from the middle ear and translates them into nerve impulses, which are again interpreted by brain cells as specific sounds.
ear [ēr]
the organ of hearing and equilibrium. (See Plates.) It is made up of the outer (external) ear, the middle ear, and the inner (internal) ear.
The outer ear consists of the auricle or pinna and the external acoustic meatus. The auricle collects sound waves and directs them to the external acoustic meatus; from there the waves travel through the external auditory canal to the eardrum (tympanic membrane).
The middle ear is separated from the outer ear by the eardrum. It contains the three ossicles, the malleus (hammer), incus (anvil), and stapes (stirrup), so called because of their resemblance to these objects. These three small bones form a chain across the middle ear from the eardrum to the oval window. The stapes causes a membrane in the oval window to vibrate, and the vibrations are transmitted to the inner ear. The middle ear is connected to the nasopharynx by the eustachian tube, through which the air pressure in the middle ear is equalized with the air pressure in the nose and throat. The middle ear is also connected with the cells in the mastoid bone just behind the outer ear. Two muscles attached to the ossicles contract when loud noises strike the tympanic membrane, limiting its vibration and thus protecting it and the inner ear from damage.
The inner ear (or labyrinth) contains the cochlea, as well as the nerves that transmit sound to the brain. It also contains the semicircular canals, which are essential to the sense of equilibrium.
When a sound strikes the ear it causes the tympanic membrane to vibrate. The ossicles function as levers, amplifying the motion of the tympanic membrane, and passing the vibrations on to the cochlea. From there the vestibulocochlear (eighth cranial) nerve transmits the vibrations, translated into nerve impulses, to the auditory center in the brain.
The outer ear consists of the auricle or pinna and the external acoustic meatus. The auricle collects sound waves and directs them to the external acoustic meatus; from there the waves travel through the external auditory canal to the eardrum (tympanic membrane).
The middle ear is separated from the outer ear by the eardrum. It contains the three ossicles, the malleus (hammer), incus (anvil), and stapes (stirrup), so called because of their resemblance to these objects. These three small bones form a chain across the middle ear from the eardrum to the oval window. The stapes causes a membrane in the oval window to vibrate, and the vibrations are transmitted to the inner ear. The middle ear is connected to the nasopharynx by the eustachian tube, through which the air pressure in the middle ear is equalized with the air pressure in the nose and throat. The middle ear is also connected with the cells in the mastoid bone just behind the outer ear. Two muscles attached to the ossicles contract when loud noises strike the tympanic membrane, limiting its vibration and thus protecting it and the inner ear from damage.
The inner ear (or labyrinth) contains the cochlea, as well as the nerves that transmit sound to the brain. It also contains the semicircular canals, which are essential to the sense of equilibrium.
When a sound strikes the ear it causes the tympanic membrane to vibrate. The ossicles function as levers, amplifying the motion of the tympanic membrane, and passing the vibrations on to the cochlea. From there the vestibulocochlear (eighth cranial) nerve transmits the vibrations, translated into nerve impulses, to the auditory center in the brain.
Diseases of the Ear. Infections and inflammations of the ear include otomycosis, a fungal infection of the outer ear; otitis media, infection of the middle ear; and mastoiditis, an infection of the mastoid cells. deafness may result from infection or from other causes such as old age, injury to the ear, hereditary factors, or conditions such as otosclerosis. Disorders of equilibrium may be caused by imperfect functioning of the semicircular canals or from labyrinthitis, an inflammation of the inner ear. Menière's disease, believed to result from dilatation of the lymphatic channels in the cochlea, may also cause disturbances in balance.
Surgery of the Ear. Surgical procedures on the ear usually are indicated for chronic infection or hearing loss. An exception is myringotomy, incision of the tympanic membrane, which is sometimes necessary to relieve pressure behind the eardrum and allow for drainage from an inflammatory process in the middle ear. Surgical procedures involving plastic reconstruction of the small bones of the middle ear are extremely delicate and have been made possible by the development of special instruments and technical equipment. stapedectomy and tympanoplasty are examples of this type of surgery, which has done much to preserve hearing that would otherwise be lost as a result of infectious destruction or sclerosis. Inner ear implants are now being performed to improve hearing in patients who have severe sensorineural hearing loss. Other surgical techniques for sensorineural hearing loss are in the developmental stage.
Patient Care. Care following surgery of the ear is aimed at preventing infection and promoting the comfort of the patient. Since the ear is so close to the brain, it is extremely important to avoid introducing pathogenic organisms into the operative site. The external ear and surrounding skin must be kept scrupulously clean. If the patient's hair is long it should be braided or arranged so that it does not come in contact with the patient's ear and side of the face. Aseptic technique must be used in all procedures carried out immediately before and after surgery.ƒ
The patient should be instructed to avoid nose blowing, especially after surgery, when there is a possibility that such an action can alter pressure within the ear. Observation of the patient after surgery of the ear includes assessing function of the facial nerve; evidence of dysfunction could include inability to wrinkle the forehead, close the eyes, pucker the lips, or bare the teeth. Any sign of facial nerve damage should be reported to the surgeon. vertigo is another common occurrence after surgery of the ear; it is usually only temporary and will subside as the operative site heals. The patient with vertigo requires special protective measures such as side rails and support when out of bed, so as to avoid falls or other accidental injuries.
Most surgeons prefer that the dressings around the ear not be changed during the immediate postoperative period. Should excessive drainage require more dressings, these can be applied over the basic dressing. Any drainage should be noted and recorded, with excessive drainage reported immediately to the surgeon. (See also care of the patient with hearing loss.)
The patient should be instructed to avoid nose blowing, especially after surgery, when there is a possibility that such an action can alter pressure within the ear. Observation of the patient after surgery of the ear includes assessing function of the facial nerve; evidence of dysfunction could include inability to wrinkle the forehead, close the eyes, pucker the lips, or bare the teeth. Any sign of facial nerve damage should be reported to the surgeon. vertigo is another common occurrence after surgery of the ear; it is usually only temporary and will subside as the operative site heals. The patient with vertigo requires special protective measures such as side rails and support when out of bed, so as to avoid falls or other accidental injuries.
Most surgeons prefer that the dressings around the ear not be changed during the immediate postoperative period. Should excessive drainage require more dressings, these can be applied over the basic dressing. Any drainage should be noted and recorded, with excessive drainage reported immediately to the surgeon. (See also care of the patient with hearing loss.)
Anatomical features of the external ear. From Ignatavicius and Workman, 2002.
Structures of the middle ear.
beach ear otitis externa caused by irritation from ocean water and other beach conditions.
cauliflower ear a thickened and deformed ear caused by accumulation of fluid and blood clots in the tissue after repeated injury; it is most often seen in boxers, for whom it is almost an occupational hazard. The ear will not recover its normal shape but can be restored to normal by plastic surgery.
swimmer's ear (tank ear) otitis externa.
ear
the organ of hearing and of equilibrium. The ear is made up of the outer (external) ear, the middle ear and the inner (internal) ear. The anatomical parts of all three can be found under their specific names. See also auricular, auditory, external ear.
The outer ear consists of the auricle, or pinna, and the external acoustic meatus. The auricle collects sound waves and directs them to the external acoustic meatus which conducts them to the tympanum.
The tympanic membrane (eardrum) separates the outer ear from the middle ear. In the middle ear are the three ossicles, the malleus (hammer), incus (anvil), and stapes (stirrup), so called because of their resemblance to these objects. These three small bones form a chain across the middle ear from the tympanum to the oval window of the inner ear. The middle ear is connected to the nasopharynx by the auditory tube, through which the air pressure on the inner side of the eardrum is equalized with the air pressure on its outside surface. Two muscles attached to the ossicles contract when loud noises strike the tympanic membrane, limiting its vibration and thus protecting it and the inner ear from damage.
In the inner ear (or labyrinth) is the cochlea, containing the nerves that transmit the electrical impulses stimulated by sound to the brain. The inner ear also contains the semicircular canals, which are essential for the sense of balance. When a sound strikes the ear it causes the tympanic membrane to vibrate. The ossicles function as levers, gearing down the motion of the tympanic membrane, and passing the vibrations on to the cochlea. From there the vestibulocochlear (eighth cranial) nerve transmits the vibrations, translated into nerve impulses, to the auditory center in the brain. See also hearing.
ear alopecia
see pinnal alopecia.
bat ear
an erect, broad-based ear in dogs; seen in the French bulldog and Welsh corgi.
bear ear
one with a very rounded tip.
break in ear
the fold line in the semi-dropped ear of dogs.
broken ear
deformed or misshapen ears, as a result of injury or congenital defect. Most often of concern in dog breeds that are supposed to have erect or specifically defined ear conformation, e.g. Collie, German shepherd dog, Chihuahua.
button ear
in dogs, an ear flap lying close to the head, and pointing toward the eye. Seen in fox terriers.
ear cancer
a squamous cell carcinoma of the ear of sheep. The lesion commences around the free edge and then invades the entire ear.
ear canker
a lay term applied generally to otitis externa but sometimes specifically to that caused by ear mites.
ear carriage
drooped, erect, alert, all indicative of mental state or state of muscle tone. Also a specified feature of breed standards for dogs.
ear cartilage
see auricular cartilage.
ear chewing
a vice of confined pigs due largely to boredom and overcrowding.
ear cyst
a misplaced tooth germ or ear tooth in horses; occur unilaterally at the base of the ear, attached to the temporal bone. Called also heterotopic polyodontia.
drop ear
an ear that is normally not erect; the end folds over or droops forward. Seen in many dog breeds.
drooping ear
inability of the ear to remain in an upright position in those species in which that is the norm. It may be a congenital abnormality, due to injury that has damaged the cartilage, or a sign of neurological deficit.
ear hematoma
see auricular hematoma.
ear mange
ear margin dermatosis
crusts, scabs and sometimes ulcerations, may occur at the edges of the external ear flap in dogs. Usually a form of seborrhea.
ear mark
patterned pieces of cartilage punched out as a means of identification. Very popular at one time with intricate codes to identify age and family groups of pigs. Marks nicked out of the edges but also the centers of the ears.
ear mites
ear notch
see ear mark (above).
ear pinna
see pinna.
ear plaque
hypertrophic dermatitis appearing as small (0.5 inch diameter) plaques on the inner surface of the ear pinna in horses. They are scaly, slightly papillomatous, painless and alopecic. The cause is unknown.
ear points
see auricular points.
ear punch
alligator forceps with cup-shaped opposing blades up to 1.5 inch diameter. A biopsy instrument for use in the depths of the ear canal.
ear rigid
ear pricked and patient unable to move them; indicative of general skeletal muscle tetany.
ear sloughing
result of phlebitis and venous thrombosis occurring in many septicemias. It is most common in pigs where it begins as purple discoloration of the ears and surrounding skin. Also part of the response in peripheral gangrene syndrome caused by ingestion of the fungus clavicepspurpurea.
spinose ear tick
see otobiusmegnini.
ear sucking
a vice occurring in penned pigs and calves caused by boredom. Has no serious effect unless it leads to cannibalism in pigs.
ear tag
a technique of animal identification favored in sheep and cattle. Has the disadvantage that tags are often lost. This can be avoided by putting duplicates in each ear. The need to catch the animal to read the tag is overcome by using large placard type tags. For cattle being worked through a chute, tail tags are more convenient. Insecticides can be incorporated into the tag to provide protection against horn fly and head fly. May contain transponders for individual identification or trace back.
ear tick
see otobiusmegnini.
ear tipping
clipping off the tip of the external ear so that the animal can be identified from a distance. Limited categories available.
ear tip necrosis
a common problem in individual pig herds; sporadic cases usually related to frostbite, thrombosis after septicemic disease, especially Salmonella dublin in young calves; herd problems may be due to ergot poisoning or endophyte-containing hay, or an ear-sucking habit.
)
Ear tip necrosis in a calf associated with Salmonella dublin infection. By permission from Blowey RW, Weaver AD, Diseases and Disorders of Cattle, Mosby, 1997
ear tooth
see polyodontia.
ear trimming
see ear cropping.
ear twitch
a rope twitch is twisted onto an ear instead of the muzzle.
ear
Physical exam The auditory apparatus, which is divided into the external ear–a conical tube that collects sound that vibrates the tympanic membrane–the outer barrier of the middle ear, which contains the
ossicles–malleus, incus, and stapes, that mechanically amplify the sound transmitted at the oval window to the cochlea; the cochlea's neuroepithelial hair cells convert the mechanical signal into an electrical/neural signal that is
identified by the brain as sounds, speech, music, etc. See Blue ear, Cauliflower ear, Inner ear, Lop ear, Malrotated ear, Middle ear, Mozart ear, Outer ear, Outstanding ear, Satyr ear, Swimmer's ear, Third ear.
Patient discussion about ear.
Q. Tinnitus (Ringing and Other Ear Noise) Anybody have this problem? Urrrrrrrrrrr, I think I want to shoot myself,you know what I mean. It is worst than the chinese torture. Someone, please send me a good tip how to stop it. I have this for 4 yrs and it is driving me crazy. You cannot enjoy total complete silence. They say silence is golden but not when you have this ringgi in your ears. It gets worst when there is no noise. The only remedy I have is eating hot spicy curry, it helps for 2-3 wks and then it comes back again and then eating spicy food again. Listening to classical music helps to. Oh well.....just have to suck it up.
A. I've read that lipoflavinoids can help.
Q. What causes high pitch ringing in one ear?
A. Many people have a ringing in their ears and there they never figure out what it is caused by. In my personal case, the ringing in my ears went away after I was treated for extreme anemia (treated with Iron).
Q. i suffer for ma chronic ear infection ! every time i take a shower i need to pay my mind that water does not go in and i'm tired of it ... every time a drop comes in i get an infection ! is there any thing out there that might help me ?
A. if ear plugs dos not help and you stile have an ear infection ,
try out the eardoc
www.eardoc.info
it is a non invasive device for reliving the ear pain by opening the ear tube.,
Read more or ask a question about eartry out the eardoc
www.eardoc.info
it is a non invasive device for reliving the ear pain by opening the ear tube.,
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