Chapter 1- 1/2. Types of Hearing Loss
Slight Hearing Loss
16-25dB. Faint speech difficult to understand in noisy enivornments
Universal Newborn Hearing Screening
1998, law passed in Virginia. Effective; July 2000. All hospitals test hearing prior to discharge of newborn. Report results to: parents, child's physician, Virginia Department of Heath (VDH)
Mild Hearing Loss
26-40dB. Faint/distant speech difficult to hear in a quiet environment. This can be serious to children learning to talk.
Moderate Hearing Loss
41-55dB. Conversational speech can only be heard in close proximity.
Moderate-Severe Hearing Loss
56-70dB. Only loud conversational speech can be heard
Severe Hearing Loss
71-90dB. Conversational speech cannot be heard unless loud and even then many words cannot be recognized.
Profound Hearing Loss
>91dB. Cannot hear conversational speech. Vision primary mode for communication. Cochlear Implants are often a consideration.
Play Audiometry
A method for assessing a child's hearing ability to teaching the child to perform simple but distinct activities, such as picking up toy or putting a ball into a cup whenever he hears the signal, either pure tones or speech.
Postlingual Deafness
After language has been developed. `
Auditory Brainstem Response (ABR)
An electrophysiologic response to sound, consisting of five peaks that represent neural function of auditory pathways. We are most concerned about the timing between 1 and 5. Absence and/or delay in response could represent a problem.
Conductive Hearing Loss
Any dysfunction of the outer/middle ear in the presence of a normal inner ear. Problem of sound conduction not perception
Prelingual Deafness
Before language is developed.
Bilateral
Both ears are affected.
Mixed Impairment Hearing Loss
Combination of a conductive or sensorineural loss. Unilateral/ Bilateral
Types of Hearing Loss
Conductive, Sensorineural (Neural) Hearing Loss, and Mixed Impairment
Sensorineural Hearing Loss
Dysfunction of inner ear or along nerve pathway from inner ear to brain stem. Problem of sound perception.
1-3-6 Goal
Hearing loss is identified by 1 month Amplification is identified by 3 months Early Intervention is began by 6 months.
Congenital Hearing Loss
In birth
Degrees of Hearing Loss
Normal (-10-20dBHL) Mild Loss (21-40dBHL) Moderate Loss (41-55dBHL) Moderately Severe Loss (56-70dBHL) Severe Loss (71-90dBHL) Profound Loss (>90dBHL)
Adventitious Hearing Loss
Occurs after birth
Unilateral
One ear is effected. Struggle does occur
Assessment of Hearing Loss
Otacoustic Emissions Test (OAE) Auditory Brainstem Response (ABR) Pure Tone Audiometry Behavioral Audiometry Play Audiometry Impedance Audiometry -Tympoanometry
Cause of Conductive Hearing Loss
Outer Ear-> wax or objects blocking canal, growth blocking canal, auricle closed Middle Ear-> otitis media, fluid, otosclerosis
Cause of Sensorineural Hearing Loss
Premature birth/birth complications, Heredity/ Non-Syndromic, Cytomegalovirus, Meningitis, Mother-Child Blood Incompatibility, and Rubella.
Tympanometry
The use of air pressure in the ear canal to test for disorders of the middle ear
Otacoustic Emissions Test (OAE)
for neonatal screening (up to cochlear hair cells)
Impedance Audiometry
hearing test using an audiometer
Behavioral Audiometry
looking for a behavioral response
Pure Tone Audiometry
used to determine threshold at each test frequency for both ears