1. Inner Ear
1.1. etched out structure within temporal bone
1.1.1. 3rd week of gestation and reaches adult size 8 fetal months
1.1.1.1. 2 main parts:vestibular ear and cochlear
1.2. TWO Main Parts
1.2.1. Vestibular= balance
1.2.1.1. Utricle
1.2.1.2. Saccule
1.2.1.3. Three semicircular canals
1.2.1.3.1. Superior (anterior)
1.2.1.3.2. Inferior (posterior)
1.2.1.3.3. Horizontal (lateral)
1.2.2. Cochlear= auditory
1.2.2.1. Scala Vestibule
1.2.2.2. Scala Media
1.2.2.3. Scala Tympani
1.2.2.4. Reissner's membrane
1.2.2.5. Basilar Membrane
1.2.2.6. Organ of corti
1.3. Fluids
1.3.1. Endolymph
1.3.1.1. contained with scale media, semicircular canals, utricle and saccule
1.3.1.2. high in potassium and very low in sodium and calcium
1.3.2. Perilymph
1.3.2.1. contained within the scala vestibule, scala tympani, and between the membranous canals and bony housing
1.3.2.2. low in potassium and high in sodium and calcium
1.3.3. How the fluid moves
1.3.3.1. Stapes pushes perilymph fluid in the scala vestibule displacing it
1.3.3.2. fluid pushes the Reissner's membrane down into the cochlear duct
1.3.3.3. Endolymph within the cochlear duct is displaced
1.3.3.4. displacement affects basilar membrane like a wave
1.3.3.5. wave moves from base to apex
1.3.3.6. there is a frequency place map
1.4. Vestibulocochlear nerve
1.4.1. connects systems of balance and hearing to the brain
1.4.2. travel together through internal auditory canal by means of the VII CN to the brain stem
1.5. Hearing Disorders
1.5.1. sensorineural hearing loss
1.5.1.1. may be severe or profound
1.5.1.2. typically affects high frequencies
1.5.1.3. speech discrimination
1.5.1.4. do not hear well in noisy environments
1.5.2. vertigo
1.5.3. tinnitus
1.5.4. dysacusis
1.6. Auditory Nerve and Central Auditory Pathway
1.6.1. cochlea to auditory cortex
1.6.1.1. 10mm long
1.6.1.2. carries the VII CN, internal auditory artery, fibres of the VII CN
1.6.2. cochlear nucleus
1.6.2.1. represents the highest centre at which processing of neural stimuli represents auditor information obtained from just one ear
1.6.3. superior olivary complex
1.6.3.1. receives info from the ipsilateral and contralateral cochlear nuclei
1.6.3.2. mediates reflex activity of tensory tympani and stapedius muscle
1.6.3.3. analyses time and intensity of sounds arriving in two ears
1.6.4. lateral lemniscus
1.6.4.1. major pathway for transmission of impulses from IPSILATERAL lower brain stem (there are contralateral too)
1.6.5. inferior colliculus
1.6.5.1. receives afferent info from both superior olivary complexes
1.6.5.2. neurons from here to the medial geniculate body are the third or fourth link the ascending pathway
1.6.6. medial geniculate body
1.6.6.1. ventral portion primarily responsile for auditory information
1.6.6.2. last subcortical relay station for auditory impulses
1.6.6.3. no decussations
1.6.7. BRAIN
1.6.7.1. frontal
1.6.7.2. parietal
1.6.7.3. occipital
1.6.7.4. temporal
1.6.7.4.1. primary auditory cortex
1.6.7.4.2. superior temporal gyrus/Heschl's gyrus
1.6.7.4.3. temporal area, insular area, parietal area, frontal area
1.6.8. Disorders
1.6.8.1. Disease
1.6.8.2. Irritation
1.6.8.3. Pressure on nerve trunk (tumor meningitis, hemorrhage trauma)
1.6.8.4. Acoustic neuroma
1.6.8.4.1. most are benign
1.6.8.4.2. vary in size
1.6.8.4.3. 95% unilateral
1.6.8.4.4. symptoms: facial weakness, numbness, change in taste, altered vision, hearing loss, dysarthria, dysphagia
1.6.8.5. CAPD
1.6.8.5.1. Central Auditory Processing Disorder
1.6.9. I see scrumptious lima beans
1.6.9.1. internal auditory canal
1.6.9.2. cochlear nucleus
1.6.9.3. superior olivary complex
1.6.9.4. lateral lemniscus
1.6.9.5. inferior colliculus
1.6.9.6. medial geniculate body
1.6.9.7. auditory cortex
1.6.9.8. brain
2. Audiologist
2.1. Audiological identification
2.2. assessment
2.3. treatment
2.4. impairment of auditory and vestibular function
2.5. Master's degree
2.6. Regulated by College of Audiologists and Speech Language Pathologists
2.7. Ontario Regulations RHPA
3. CASLPO
3.1. Making sure all clinicians have same standard
3.2. Counselling for 10 mins if session is 1 hour, then refer
3.3. Standards= MUST be accountable
3.3.1. Example: Audiologists MUST have the required resources in order to perform hearing assessment in adults
3.4. Guidelines= Advising
3.4.1. Example: Audiologists should consider modification or discontinuation of an assessment if the presenting condition of the external ear or ear canal requires treatment
4. Sound and Pure Tone Audiometry
4.1. Behavioural Test
4.2. determine the sensitivity of human auditory system across a frequency range
4.3. pure tone air: measure sensitivity of outer, middle, and inner ear
4.4. pure ton bone measures sensitivity of inner ear and VII CN
4.5. pure tone audiometer
4.5.1. sound source
4.5.2. amplifier
4.5.3. on/off switch
4.5.4. interrupter switch
4.5.5. attenuator
4.5.6. power source
4.5.7. frequency selector
4.5.8. masking controls
4.6. Conductive Hearing Loss
4.6.1. bone conduction results= normal
4.6.2. air conduction results= abnormal
4.7. Sensorineural Hearing Loss
4.7.1. bone conduction results= abnormal
4.7.2. air conduction results= abnormal
4.8. Mixed Hearing Loss
4.8.1. air born gap with air being worse than bone
4.9. Air conduction= degree of hearing loss
4.9.1. Components
4.9.1.1. earphones
4.9.1.1.1. circum-aural
4.9.1.1.2. inserts
4.9.2. directed from the audiometer to the diaphragm of the earphone causing it to vibrate in sync with the frequency and intensity
4.10. Bone conduction= what type of hearing loss you have
4.10.1. Components
4.10.1.1. Bone conduction vibrator
4.10.1.2. plastic strap
4.10.1.3. spring-steal headband
4.10.2. directed from the audiometer to the small bone-conduction vibrator with greater energy than air conduction
4.11. Levels of Hearing
4.11.1. 0 to 20 dB= within normal limits
4.11.2. 21 to 40 dB= slight to mild loss
4.11.3. 41 to 55 dB= moderate loss
4.11.4. 56 to 70 dB= moderately severe loss
4.11.5. 71 to 90 dB= severe loss
4.11.6. 91+dB= profound loss
5. Case History
5.1. allows you to make pjhysical observations, retrieve patient's opinion, discover accompanying symptoms, discover history and exposure
5.2. things in case history
5.2.1. asking questions about when hearing loss occured
5.2.2. ask info about general health
5.2.3. do you have any other children with hearing loss
5.2.4. academic performance
5.2.5. social activities
5.2.6. have they reached all developmental milestones?
5.2.7. pain in ear
6. Speech Audiometry
6.1. battery of tests that measures what level a patient considers the presentation of stimulus to be uncomfortable
6.2. Speech Detection Threshold (SDT) Speech-Reception Threshold (SRT) Speech-Recognition Test (SRS) or Word-Recognition Test (WRT) Most Comfortable Loudness Level (MCL) Uncomfortable Loudness Level (UCL)
7. Transient evoked Otoacoustic Emission
7.1. measures the sounds emitted in response by the cochlea’s outer hair cells to an acoustic stimulus
8. Management
8.1. Referral
8.2. Treatment plans
8.3. Hearing aid reccomendations
8.4. Surgery
8.5. Support groups
9. Outer Ear
9.1. Contains
9.1.1. pinna
9.1.1.1. directs sound
9.1.2. helix
9.1.3. scaphoid fossa
9.1.4. concha
9.1.5. tragus
9.1.6. ear lobe
9.1.7. external auditory canal
9.1.7.1. one inch long
9.1.7.1.1. ear canal
9.1.8. tympanic membrane
9.1.8.1. ear drum
9.1.8.1.1. sem-transparent and vibrates
9.1.9. vestigial muscles
9.2. Disorders of the auricle
9.2.1. anotia: complete absence of pinna
9.2.2. tumor
9.2.2.1. slowly growing
9.2.2.2. distorts auricle and destrots normal architecture
9.2.2.3. resembles cauliflower ear
9.2.2.4. hard and cannot be compressed by squeezing it with fingers
9.2.3. painless
9.2.4. cauliflower ear
9.2.4.1. sign of a warrior
9.2.4.2. repeated lows to the head
9.2.4.3. permanent deformity
9.2.5. auricular hematoma
9.2.5.1. caused by direct trauma to pinna
9.2.5.2. torn perichondrial vessels bleed between detached perichondrium and underlying cartilage
9.2.6. Psoriasis
9.2.7. Bifid earlobe
9.3. Disorders of the External Auditory Meatus
9.3.1. cerumen
9.3.2. foreign bodies
9.3.3. atresia
9.3.4. stenosis
9.4. Disorders of the Tympanic Membrane
9.4.1. perforation
10. Middle Ear
10.1. responsible for mechanical transfer of sound
10.2. The ossicles
10.2.1. malleus
10.2.1.1. incus
10.2.1.1.1. stapes
10.3. Eustachian tube
10.3.1. vents middle ear to nasopharynx
10.3.1.1. provides the middle ear with air ventilation/oxygen
10.3.1.1.1. opens and closes to keep air pressure equal during yawning, swallowing, chewing, talking, flying, or excessive pressure from the nose
10.4. Middle Ear space
10.5. Epitympanic recess
10.5.1. roof of middle ear is a thin layer of bone which separates ear from the brain
10.5.1.1. opening in posterior wall of recess that connects with the tympanic antrum
10.5.1.1.1. antrum connects with air cells of the mastoid portion of temporal bone
10.6. Oval window
10.6.1. allows the promontory
10.6.1.1. filled by a membrane that supports the base of the stapes
10.6.1.1.1. moves in and out with movement of the stapes
10.7. Round window
10.7.1. below the promontory
10.7.1.1. covered by very thin, tough elastic membrane
10.7.1.1.1. circular shaped
10.8. Middle Ear Disorders
10.8.1. otitis media
10.8.2. facial palsy
10.8.3. barotrauma
10.8.4. otosclerosis
10.8.5. ossile deformities
10.8.6. cholesteotoma
10.9. Treatments
10.9.1. antiobiotics
10.9.2. myringotomy
10.9.3. myringotomy
10.9.4. stapes mobilization
10.9.5. stapedotomies
10.9.6. tympanloplasty
10.9.7. mastoidectomy
11. Employment
11.1. Hospital
11.2. Doctor's Office
11.3. Private Practice
11.4. University
11.5. School for Hearing Impairment
11.6. Industry
11.7. Research
12. Types of Hearing Loss
12.1. Mixed Hearing Loss
12.2. Sensorineural Hearing Loss
12.2.1. neuritis
12.2.2. meniere's disease
12.2.3. noise induced hearing loss
12.2.4. ototoxic drugs
12.2.5. acoustic neuroma
12.3. Conductive Hearing Loss
12.3.1. causes
12.3.1.1. otitis media
12.3.1.2. otosclerosis
12.3.1.3. performation of tympanic membrane
12.3.1.4. break in ossicular chain
12.3.1.5. congenital malformation
13. Full Audiological Evaluation
13.1. Case History
13.2. Physical Examination
13.3. Pure Tone Audiometry
13.4. Speech Audiometry
13.5. ABR/OAE
13.6. Management
14. Auditory Brainstem Responses
14.1. examine how the cochlea is functioning
14.2. mastoid process and forehead, and another set of electrodes will be placed on the opposite mastoid, the forehead OR neck
14.3. one ear will be tested at a time, a series of clicks will be presented through headphones to measures responses from your brain
15. Physical Examination
15.1. 3 tests
15.1.1. 1. Static compliance
15.1.1.1. compliance of your eardrum
15.1.2. 2. Tympanometry
15.1.2.1. uses the eardrum compliance at various air pressures to measure middle ear pressure.
15.1.3. 3. Acoustic reflex
15.1.3.1. muscle contraction in your middle ear, in response to the stimulus