This document discusses disorders of the auditory nervous system, including acoustic neuromas and auditory neuropathy spectrum disorder. It begins by categorizing auditory nervous system disorders as affecting the auditory nerve, cochlear nuclei, or higher pathways. Acoustic neuromas are benign tumors of the auditory nerve that can cause hearing loss and tinnitus. Auditory neuropathy spectrum disorder involves abnormal nerve transmission from the cochlea to brainstem. The document also covers evaluation, diagnosis and management of these conditions.
2. Can be broken up into three categories:
◦ Disorders of the auditory nerve
◦ Disorders of the cochlear nuclei
◦ Disorders of the higher auditory pathways
Pathology of the auditory nervous system is
often referred to as a RETROCOCHLEAR
pathology, meaning a disorder occurring after
the cochlea
4. A benign (non-cancerous) tumor that grows on
the auditory nerve (CN VIII)
Also referred to as an acoustic tumor or
vestibular schwannoma
◦ Occur at a rate of 1/100,000 every year
◦ In 95% of cases, tumors are unilateral (one ear only)
Classic signs of acoustic neuroma
◦ Asymmetrical, sensorineural hearing loss in the high
frequencies
◦ Poorer word recognition score in affected ear
◦ Unilateral tinnitus
◦ May also be associated with dizziness
◦ If the tumor is big enough to press on the facial nerve
(CN VII), may report facial weakness/numbness
6. It is important that you refer patients to an
ENT physician if they exhibit an asymmetrical
hearing loss and unilateral ear symptoms
Auditory brainstem response (ABR) testing
may be performed by an audiologist
Magnetic resonance imaging (MRI) of the
internal auditory canals is the gold standard
for diagnosis, as ABR testing may miss small
tumors
7. Do nothing
◦ If the tumor is small enough, it will be monitored
for growth
Surgical removal
◦ Usually results in total hearing loss in affected ear
Narrow-beam radiation (Gamma Knife) to
stop tumor growth, which preserves hearing
8. May wear a hearing aid in the affected ear,
but hearing should be tested regularly to
monitor for changes in hearing sensitivity and
speech understanding
9. I will refer to ANSD as auditory neuropathy
Auditory neuropathy refers to a condition in
which there is normal cochlear function, but
the transmission of electrical information
along the auditory nerve, from the cochlea to
the brainstem, is dys-synchronous (not
smooth).
10. Varies from patient-to-patient, which is why
it is referred to as a spectrum disorder
Will exhibit a range from normal hearing to
profound SNHL
◦ Most often will find a mild to moderate SNHL that is
progressive (getting worse)
Great difficulty understanding speech,
especially in the presence of fairly good
hearing thresholds
Diagnosed based on audiometric findings,
absence of an ABR response, normal MRI
11. Hearing aids may help
Often hearing aids are of very limited benefit,
and cochlear implants are recommended in
these situations
12. Nearly impossible to diagnose with certainty,
but there may be abnormalities along the
auditory brainstem that results in
sensorineural hearing loss
Usually due to disease, toxicity, irritation,
pressure, trauma
◦ Stroke, anoxia, syphilis, congenital malformation,
aging, multiple sclerosis
14. The presence of language and learning
disabilities due to auditory deprivation in
young children
The auditory deprivation is often due to the
slight/mild conductive hearing losses that
accompany undiagnosed/untreated otitis
media
15. Characterized by:
◦ No response to puretone testing on the audiogram
◦ These patient’s cannot “hear”, but they have normal
acoustic reflexes and ABRs
Usually due to several compromise of both
brain hemispheres due to a vascular lesion
◦ Very rare
16. A deficit in the neural processing of auditory
stimuli that is not due to higher order
language or cognitive factors
Difficulty identifying and interpreting auditory
information in the absence of peripheral HL
◦ The ear and the brain do not coordinate well
◦ Auditory information breaks down somewhere
between the ear and the brain
17. Delay in development
◦ Auditory deprivation secondary to otitis media,
much like MADS
Disordered development of the auditory
nervous system
Specific central lesion
May be acquired in adults due to head injury,
stroke, brain tumor, or multiple sclerosis
◦ More prevalent in males
18. Behaves like they have a hearing loss
◦ Says “huh” or “what” frequently
◦ Inconsistent response to auditory stimuli
◦ Often misunderstands what is said
◦ Constantly requests that information be repeated
Poor listening skills
◦ Inattentive
◦ Easily distracted
◦ Restless
Difficulty understanding speech in noise
Poor academic performance
19. Difficulty with phonics and auditory
discrimination
◦ confuses words that sound alike
◦ Has problems with reading, spelling, and vocabulary
Poor auditory memory
◦ Difficulty following oral directions
◦ Learns poorly through auditory channel
Poor receptive and expressive language
Gives slow or delayed response to verbal stimuli
Difficulty understanding rapid speech or
unfamiliar dialect
Issues with gross and/or fine motor skills
Poor musical abilities
◦ Does not recognize sound patterns or rhythm
◦ Poor vocal prosody
20. The individual MUST have:
◦ Normal hearing
◦ Normal intelligence
May co-exist with:
AD/HD*
Learning disabilities
Speech/language delays
Reading disorder
Autism spectrum disorder
21. Educational Assessment
◦ Psychological/IQ testing
◦ Speech/language assessment
Audiology Assessment
◦ Puretone and speech testing
◦ Tympanometry and reflexes
◦ OAEs
◦ Electrophysiology
APD Battery
◦ Monaural tasks in background noise
◦ Auditory pattern recognition
◦ Binaural separation and integration
Dichotic vs. Diotic stimuli
Includes verbal and non-verbal stimuli
22. Based on the results of the APD evaluation
◦ Where is the weakness?
Specific skill training
Modify the listening environment
Assistive Listening Devices
◦ increase the signal-to-noise ratio
Speech-Language Therapy
Environmental modifications to reduce noise
and reverberation
23. Extended time on assignments
◦ Format adaptations on homework questions
Classroom VISUALS
Classroom accommodations
Written notes/note buddy
Study guide
Set of texts at home/books on tape
Test-taking adaptations
◦ Quiet area
◦ Modified format
◦ Extended time
◦ Segmented testing over multiple days
24. Feel free to stop reviewing the
powerpoint now
25. Dichotic Tests(Simultaneous & Different
Stimuli):
◦ Binaural Integration
Dichotic Digits (DD)
Dichotic Sentence Identification (DSI)
Staggered Spondaic Word (SSW) Test
◦ Binaural Separation/Selective Auditory Attention
Synthetic Sentence Identification (SSI-CCM)
Competing Sentences Test (CST)
30. Diotic (Simultaneous and Same Stimuli):
◦ Auditory Patterning/Temporal Ordering
Pitch Pattern Sequence (PPS)
High vs. low pitch
Duration Patterns (DP)
Long vs. short
Gap Detection
