CGSC379 Chapter 7

diabetes

a metabolic disease affecting the pancreas; causes deficiency of insulin and misuse of glucose; can cause auditory deficits as a result of elevated blood glucose levels on the inner ear or as a result of small blood vessel changes in the body; progressive, bilateral, sensorineural hearing loss with greatest loss at high frequencies

collapsing ear canal

a non-pathological condition that results from a loss of elasticity in the cartilage of the external ear; causes poor air conduction; typically affects older individuals and young infants

noise notch

a pattern in an audiogram of someone with noise-induced hearing loss; characterized by a high-frequency hearing loss with the greatest loss at 4,000 Hz and some recovery by 8,000 Hz

mastoiditis

a potential complication of otitis media; occurs when infection in the middle ear spreads to the mastoid bone via the attic portion of the middle ear;

cytomegalovirus (CMV)

a herpes-related virus, dormant in the body; can be a complication in pregnancy throughout the full term; transmitted through saliva, feces, urine, etc; is sometimes asymptomatic and is usually present in the 2nd or 3rd baby in a family (if it's genetic)

melanoma

a malignancy of pigment cells that spreads through the blood stream; has a high mortality rate associated with it; can be common in older adults

barotrauma

condition of the middle ear caused by marked changes in atmospheric pressure; leads to perforation of the tympanic membrane

toxoplasmosis

condition that comes from cats through chemical in litter box

most common hearing loss gene

connexin 26 "CX26" or GJB2; a mutation in a protein that makes the ear operate normally

discontinuity of the ossicular chain

damage to the ossicular chain that can involve one or all of the ossicles; can consist of a break or fracture in the manubrium, incus, or stapes or the dislocation of the incus; results from head trauma with or without skull fracture or from direct trauma to the tympanic membrane; characteristics include large unilateral conductive hearing loss; requires surgical repair of the bones involved or replacing an ossicle with wire or teflon

ototoxicity

disorder causing degenerative changes in the inner ear; caused by certain drugs that are poisonous to the inner ear; drugs of this type include amino glycoside antibiotics (can cause deafness if you carry a gene sensitive to this drug), diuretics, aspirin, chemotherapy agents, and quinine (drug for malaria treatment; can be congenital or acquired; causes bilateral sensorineural hearing loss that can be monitored during treatment with ultrahigh-frequency audiometry (because hearing loss usually occurs at ultrahigh-frequency first)

disrupted blood supply

disorder in which blood is not circulating properly; can cause hearing loss depending on the degree to which blood supply is reduced and the location of the disruption; can include (1) transient ischemic attacks - small strokes (2) arteriosclerosis - the hardening of arteries (3) aneurysm - the bursting of a blood vessel

trauma

disorder of severe injury; when it involves damage to the head, the ear is the most affected sensory structure which can lead to hearing loss; includes fracture of the temporal bone

facial nerve disorders

disorder of the seventh cranial (facial) nerve; caused by edema (swelling) compression of the nerve, reduced blood flow, or viral infections; has symptoms based on the specific pathology - impaired tearing, eyelid function, salivation, taste, or facial muscle weakness; may cause an ABSENCE OF ACOUSTIC REFLEX BUT NORMAL HEARING THRESHOLDS

hereditary motor-sensory neuropathies (HMSN)

disorders that can affect the spiral ganglia and may produce auditory symptoms and/or abnormal results on tests of auditory function; involve degeneration and atrophy of peripheral motor and sensory neurons; most common disorders are (1) charcot-marie-tooth and (2) friedrich's ataxia (neurodegenerative)

cerumen

earwax; formed from a combination of secretion from ceruminous and sebaceous glands that line the outer third of the external auditory canal; protects the ear by trapping substances that might enter the ear canal; can sometimes accumulate in the external auditory canal causing occlusion (conductive hearing loss); caused by over-use of cotton swabs, narrow ear canals, and/or hearing aid use

cranial nerve X (vagus)

external auditory canal, back of throat (via collateral innervation with cranial nerve IX)

metabolic presbycusis

hearing loss that occurs due to the aging process, caused by reduced blood supply to the stria vascularis; results in reduced responsiveness of hair cells leading to reduced hearing sensitivity

neural presbycusis

hearing loss that occurs due to the aging process, caused by the degeneration of the spiral ganglion

cochlear presbycusis

hearing loss that occurs due to the aging process; only affects very low and very high frequencies

complications of outer ear malformations

if outer ear malformations exist, kidney problems can also occur due to the early development of the ear from tissues found in other areas of the body

otitis media (OM)

inflammation of the middle ear; any condition resulting in the accumulation of middle ear fluid; many types classified by the effusion present and duration of condition; treated by antibiotics or myringotomy

eustachian tube dysfunction

involves insufficient opening of the eustachian tube, which disrupts its pressure equalization function, resulting in a buildup of negative pressure in the middle ear space; can be caused by (1) swelling due to allergy or infection (2) obstruction due to enlarged adenoids or a tumor (3) neurological disorders that interfere with the opening of the tube (4) craniofacial anomalies (5) changes in air pressure or (6) abnormal anatomical shape and size; can be difficult to treat, causes conductive hearing loss but treatments can include antibiotics for allergies and sinusitis or surgery to remove obstruction; most common in children

hyperbilirubinemia

jaundice

cranial nerve VII (facial)

muscles of face, ear canal

contra coup effect

occurs when damage occurs to the side of the brain that is opposite the side of impact in trauma; can be found in transverse fracture of the temporal bone and in tumors

cranial nerve IX (glossopharyngeal)

sensory input for throat, back of mouth, tonsil area, and part of tongue; also innervates inside of tympanic membrane, middle ear cavity

types of otitis media

serous - middle ear inflammation accompanied by a thin, watery fluid mucoid - middle ear inflammation with thicker effusion suppurative - thick, yellow pus adhesive - middle ear inflammation involving a thickening of the fibrous tissue of the tympanic membrane that may be accompanied by severe retraction of the tympanic membrane and negative pressure in the middle ear space

ECMO

stands for extra corporal mechanical oxygenation; procedure in which blood is given oxygen mechanically outside of the body and then reinserted into the body; needed for mechonium aspiration (breathing in toxins from first bowel if occurs before birth)

syndromes that can occur with hearing loss

(1) Waardenburg (2) Treacher-Collins (3) Pendred (4) Usher (5) BOR (6) Stickler (7) lport (8) NF2 (9) Jervell-Lange-Neilson (10) CHARGE

four nerves of the ear

(1) cranial nerve V (trigeminal) (2) cranial nerve VII (facial) (3) cranial nerve IX (glossopharyngeal) (4) cranial nerve X (vagus)

causes of hearing loss

(1) genetics - more than 60% of cases, with 80% being syndromic (2) prematurity - characterized by weight less than 3.3 lbs and less than 32 weeks gestation at time of birth (3) in utero infections (4) post-natal infections (5) chemotherapy (6) trauma (7) noise induction

complications of eustachian tube dysfunction

(1) retraction pocket of the posterior pars tensa (2) accumulation of serous or mucoid fluid in them idle ear space persistent condition associated with otitis media

genetics breakdown for hearing loss

70% of genetic hearing loss comes from recessive genes of both parents, 15% comes from dominant gene, 15% comes from x-linked (connected to female gene) or mitochondrial conditions (very disastrous)

otorrhea

a foul odo emanating from a patient's ear; could be a fungal infection, middle ear infection, or foreign object (ear canal swells up and gets infected)

Meniere's diseases

a benign disorder of the inner ear; results from INCREASED ENDOLYMPHATIC FLUID PRESSURE, leading to symptoms of tinnitus, fullness and/or pressure in the ear,fluctuating sensorineural hearing loss, or vertigo; symptoms can come in waves and is often caused by UNKNOWN ETIOLOGIES

abscess

a collection of living and dead bacteria

cochlear neuritis

a complication of neurofibromatosis; caused by INFLAMMATION OF CRANIAL NERVE VIII; causes the normal functioning of auditory neurons to be disrupted, resulting in hearing loss/deafness; can also cause balance problems if the vestibular portion of cranial nerve VIII is affected; removal of this tumor SEVERS THE NERVE CAUSING DEAFNESS

patulous eustachian tube

a condition in which the eustachian tube is abnormally open; may be caused by rapid weight loss or neuromuscular disorders involving the muscles of the nasopharynx; symptoms include aural fullness, auto phony and hearing respiratory sounds

auditory neuropathy/dys-synchrony spectrum disorder

a condition in which the patient displays auditory characteristics that support normal outer hair cell function and abnormal results from the cranial nerve VIII and brainstem caused by abnormal transmission in VIII nerve; cannot be identified by CT scan, but can be by (1) acoustic reflex testing (2) otoacoustic emissions test (normal) and (3) auditory brainstem response (abnormal/absent); can be mistaken for cochlear impairment or central auditory processing disorder; can be caused by genetics, hyperbilirubinemia

cauliflower ear

a condition in which the pinna changes shape due to repeated injury

multiple sclerosis

a disease of the central nervous system characterized by destruction of the myelin sheath of nerve fibers (demyelination); may affect hearing because it results in the formation of sclerotic plaques on the brainstem and may also cause changes in portion of cranial nerve VIII

atresia

a disease of the external auditory canal involving absence of the normal opening to the canal; may be congenital or acquired, unilateral or bilateral; may be membraneous (tissue plug present between external and middle ear) or bony (wall of bone between external and middle ear); often syndromic (occurs with other disorders), with Treacher-Collins being the most common; requires surgical construction

presbycusis

a progressieve loss of hearing resulting from the aging process; usually characterized by a bilateral, symmetrical sensorineural loss affecting the higher frequencies, particularly 2,000 to 8,000 Hz and a decline in word recognition ability; onset and degree vary, and other factors such as noise exposure cannot be ruled out to diagnose it; has three main types: (1) cochlear (2) neural and (3) metabolic

myringotomy

a surgical procedure in which an ENT makes an incision in the eardrum to drain the middle ear fluid and then inserts a pressure equalization (PE) tube to keep it open and to prevent the recurrence of negative middle ear pressure

stapedectomy

a surgical procedure in which the stapes is removed and is replaced with a synthetic prosthesis between the incus and the oval window; a potential treatment option for otosclerosis

cholesteatoma

a tumorlike mass that can be formed from marginal perforation of the tympanic membrane or chronic otitis media; symptoms include ottorrhea, hearing loss, vertigo, tinnitus, pain, headache, facial nerve paralysis, and eustachian tube dysfunction; involves surgical removal

noise-induced hearing loss

a usually-progressive hearing loss that results from exposure to sound pressure levels capable of damaging the hair cells in the cochlea (BUT can be due to noise trauma such as a gunshot at greater than 140 dB); starts at the basal portion of the cochlea (the 4K notch); depends on intensity and duration of exposure, patient susceptibility, etc.; can sometimes have a shift back to normal hearing over time

hemotympanum

accumulation of blood in the middle ear

otosclerosis

also called otospongiosis; a genetic disorder common in middle-aged women, characterized by a lesion of the osseous or bony portion of the inner ear and of the stapedial footplate; results when a layer of new bone is laid down at the same time older bone is resorbed, producing a spongy type of bone; usually occurs in the portion of the oval window just anterior to the stapes footplate, causing the footplate to wedge in position and preventing it from moving posteriorly; results in conductive hearing loss and usually occurs bilaterally; can be seen in bone conduction as a loss of hearing at approximately 15 dB and 2,000 Hz; treatment options include stapedectomy or hearing aids

tympanic membrane perforation

an abnormal opening in a structure of the tympanic membrane; three types: (1) central perforation, (2) marginal perforation, and (3) retraction pockets (not true perforations; can cause hearing loss 0 - 40 dB depending on size and location of perforation or presence of infection; caused by trauma, thermal burns, foreign bodies in ear canal, skull fractures, ear infections

microtia

an abnormally small pinna; typically occurs with atresia; patient may or may not have an open ear canal; also used to describe a broader range of abnormalities of the external ear (ear has normal landmarks but small in size or pinna tissue doesn't resemble normal external ear

acute external otitis

an infection of the external ear characterized by inflammation in the external ear and external auditory canal; also called "swimmer's ear"; caused by fluid collection in the tissues and red blood cells, causing the ear to be very tender; symptoms include pain, drainage, and hearing loss (due to the closing off of the external auditory meatus); can be treated with mix of water and vinegar

perichondritis

an infection of the skin involving the perichondrium (nutritive connective tissue); the next level of external ear infection; characterized by edema (swelling), redness, and tenderness; can progress to the cartilage if left untreated; can be caused by ear piercings if the piercing hasn't been controlled for infection

cellulitis

an infection of the skin, not involving the perichondrium (nutritive connective tissue); may cause an abscess if untreated

malleus fixation

an uncommon middle ear disorder involving fixation of the malleus head; may be total or partial and may result from genetics, infection, tympanosclerosis, otosclerosis, or a fracture of the attic wall; can also be congenital; causes conductive hearing loss (loss of transmission) in audiometric results

vestibular schwannoma

benign tumor affecting the AUDITORY NERVE (VIII nerve) that arises from the vestibular portion of the auditory nerve, specifically affecting the Schwann cells that form the myelin sheath covering the nerve; usually begin inside the internal auditory canal; as it grows/worsens, can lead to hearing loss, pressure on the bone of the auditory canal and affixation to the brainstem; treated with surgery; shows up as asymmetrical sensorineural hearing loss in audiogram; patients often report FULL FEELING IN EAR; POOR SPEECH DISCRIMINATION

kernicterus

bilirubin-induced brain dysfunction

fracture of the temporal bone

can be longitudinal or transverse; 80% of cases are longitudinal

injuries of the external ear

can occur due to sunburn, frostbite, chemical injuries, radiation, and trauma caused by aggressive insertion of a foreign object; can also occur due to sports injuries, causing cauliflower ear

basal cell carcinoma

carcinoma of the external ear in which the basal skin layer grows out of control but does not metastasize; may spread locally and is malignant; usually related to sun exposure and may occur anywhere on the pinna

recurrent otitis media

otitis media occurs more than three or more times in a 6-month period

persistent otitis media

otitis media that lasts 6 weeks or longer after the initiation of antibiotics

chronic otitis media

otitis media that lasts for a period longer than 8 weeks

central perforation

perforations in the pars tensa of the tympanic membrane in which the rim of the perforation does not make contact with the annulus

marginal perforation

perforations involving the annulus in which skin can migrate into middle ear space; more dangerous that central perforation because migration of skin into middle ear space can cause cholesteatoma

tympanoplasty

reconstructive surgery of the middle ear

attic retraction pockets

retraction "perforations"; pockets that occur when negative middle ear pressure causes the eardrum to retract (pull in) and a pocket forms in the area of the pars flaccida; pocket can fill with squamous debris and cause and attic cholesteatoma

myringoplasty

surgical repair

effusion

the escape of a fluid into a body space

squamous cell carcinoma

the most common malignant tumor of the external ear; more invasive because it can travel via blood vessels and the lymph system; usually found on the pinna in males and near the concha in females

glomus tumors

the most common slow-growing benign tumor of the MIDDLE EAR and of the temporal bone after acoustic neuromas; can occur in the jugular bulb (glomus jugulare), middle ear (glomus tympanicum), or along the vagus nerve (glomus vagale); can disrupt the ossicular chain requiring surgery

Bell's palsy

the most common type of facial nerve disorder; a viral infection involving the drooping of one side of the face

stenosis

the narrowing of the external auditory canal; may occur from trauma, inflammation due to infection, genetics, and aging (due to weakening of the muscles supporting the walls of the ear canals)

vertigo

the sensation go motion or spinning

tinnitus

the sensation of sound in the head or ears

otalgia

the term used for ear pain; more than half of the time is caused by a condition in another part of the body; caused by pain in one of the four nerves innervating the ear

ankylosis

the wedging of position of the stapes in the oval window

carcinoma of the external ear

three types: (1) basal cell carcinoma (2) squamous cell carcinoma (3) melanoma

cranial nerve V (trigeminal)

tympanic membrane, jaw, and temporomandibular joint (TMJ)

longitudinal fracture of temporal bone

type of temporal fracture causing fracture of the external ear canal, tearing of the tympanic membrane, and damage to the middle ear and cochlea ( damage occurs in middle/outer ear mostly); may cause leakage of fluid or hemotympanum; the hearing mechanism CAN be repaired from this injury

transverse fracture of the temporal bone

type of temporal fracture that violates the cochlea, semicircular canals, and or the internal auditory canal; results from a blow to the back of the had and is associated with a high incidence of facial nerve paralysis; results in sensorineural hearing loss or vertigo; can cause perilymph leak and rupture of the oval/round windows; higher mortality rate than longitudinal type; the hearing mechanism CANNOT be repaired from this injury

neurofibromatosis

type of vestibular schwannoma that is the cause of two different diseases: neurofibromatosis 1 and neurofibromatosis 2; nf1 results in multiple tumors on the skin and spinal cord (rarely involves the ear) and NF2s results in fast growing bilateral acoustic tumors

cysts, pits, and tags

types of outer ear malformations; tags are extra pieces of skin, pits are holes (perforations....see next few slides) and cysts are sacks of fluid; cysts and pits exist in anterior to the pinna usually