Hearing Aids Exam 2 UPDATED ACTUAL
Exam Questions and CORECT Answers
Earmold fittings affect what three broad acoustic characteristics of the hearing aid? - CORRECT
ANSWER - 1) shape of the gain-frequency response of the aid when it is mounted in the
ear (insertion loss- affects how the sound is transmitted)
2)self perceived quality of the patient's voice (occlusion effect)
3) likelihood for feedback
Explain the insertion loss concept. - CORRECT ANSWER - Without an ear mold, as
sound travels through the ear it is affected by the natural ear canal resonance curve (resonates at
higher frequencies) but is still perceived by the listener equally across frequencies.
When putting an ear mold in the ear, this changes the resonance curve of the ear and also affects
the perceived response. Instead of all frequencies being perceived equally there is a reduced
perception of high frequencies cause by the insertion of the ear mold
Selecting an ear mold is a ____________________ step in the hearing aid selection process. -
CORRECT ANSWER - secondary
What do you have to consider when choosing an ear mold? - CORRECT ANSWER --
degree of loss
-need for venting
-shape, size, and texture of patient's ear
-age
-dexterity
What are the four objectives for hearing aid coupling/and fitting ear molds? - CORRECT
ANSWER - -provide a satisfactory acoustic seal (prevent feedback)
-retain the hearing aid on the pinna
-be comfortable
,-be aesthetically acceptable to the patient
What are the 4 different type of ear mold materials? - CORRECT ANSWER - -acrylic
-silicone
-polyvinyl chloride
-polyethylene
Describe acrylic ear mold material. - CORRECT ANSWER - -very hard and durable
-easy to modify
-easy to insert and remove (dexterity)
-may not get a tight seal
-will not bend or compress for narrow ear canals
-appropriate for most older adult fittings/mild moderate losses
T/F: Acrylic ear molds are typically recommended for children. - CORRECT ANSWER -
FALSE - due to concern for injury if struck while wearing the ear mold
Describe silicone ear mold material. - CORRECT ANSWER - -available in tacky/low
pressure cured and high pressure cured varieties (good for many types of losses)
-most appropriate for children
-most appropriate for severe to profound losses
-fairly hypoallergenic
-difficult to modify due to softness
-most difficult to insert
-tubing adhesives may not stick so may need tube lock
Why are silicone ear molds good for severe to profound hearing loss? - CORRECT
ANSWER - because the mold fits down better in the ear canal and does not create
feedback
,If you had a patient with dexterity issues, what ear mold material would you be most likely to
choose? which would you be least likely to choose? - CORRECT ANSWER - most likely
- acrylic
least likely - silicone
Describe polyvinyl chloride ear mold material. - CORRECT ANSWER - -available in
softer and harder varieties
-more comfortable than acrylic
-good for moderate to severe losses
-not as durable
-can be difficult to modify
-more prone to discoloration
-problematic for patients with vinyl allergies
Describe polyethylene ear mold material. - CORRECT ANSWER - -similar to acrylic but
more prone to feedback
-used the least often
-plastic like appearance
-most hypoallergenic
What are three different ways for naming ear mold styles? - CORRECT ANSWER --
descriptive name
-naming after inventor
-naming after original application
For a severe to profound loss, what is the typical ear mold fitting? - CORRECT
ANSWER - silicone full shell ear mold
, For a mild to moderate hearing loss, what is the typical ear mold fitting? - CORRECT
ANSWER - acrylic skeleton ear mold
What are the 6 typical ear mold styles? - CORRECT ANSWER - -full shell
-half-shell
-skeleton
-canal
-custom open fit (CROS)
-modular earmold plumbing (domes)
A full shell ear mold style is good for what two things? - CORRECT ANSWER - -severe
to profound loss
-children
Describe a skeleton ear mold style. - CORRECT ANSWER - -common and useful for a
wide range of hearing loss
-sometimes modified to remove the middle portion of the ring that fills the concha bowl (semi
skeleton)
-good for fitting people with weird ear anatomy
Describe a canal ear mold style. - CORRECT ANSWER - -good for mild to moderate loss
-does not fit as tight
-retention can be an issue (can add a canal or helix lock)
-choose for someone who has cosmetic issues
Describe a custom open fit ear mold style. - CORRECT ANSWER - -called a CROS style
and is typically only used for a CROS device
-when you need an open fit but have retention or dexterity issues
-many styles with various configurations of the heel, concha, and helix lock portions
Exam Questions and CORECT Answers
Earmold fittings affect what three broad acoustic characteristics of the hearing aid? - CORRECT
ANSWER - 1) shape of the gain-frequency response of the aid when it is mounted in the
ear (insertion loss- affects how the sound is transmitted)
2)self perceived quality of the patient's voice (occlusion effect)
3) likelihood for feedback
Explain the insertion loss concept. - CORRECT ANSWER - Without an ear mold, as
sound travels through the ear it is affected by the natural ear canal resonance curve (resonates at
higher frequencies) but is still perceived by the listener equally across frequencies.
When putting an ear mold in the ear, this changes the resonance curve of the ear and also affects
the perceived response. Instead of all frequencies being perceived equally there is a reduced
perception of high frequencies cause by the insertion of the ear mold
Selecting an ear mold is a ____________________ step in the hearing aid selection process. -
CORRECT ANSWER - secondary
What do you have to consider when choosing an ear mold? - CORRECT ANSWER --
degree of loss
-need for venting
-shape, size, and texture of patient's ear
-age
-dexterity
What are the four objectives for hearing aid coupling/and fitting ear molds? - CORRECT
ANSWER - -provide a satisfactory acoustic seal (prevent feedback)
-retain the hearing aid on the pinna
-be comfortable
,-be aesthetically acceptable to the patient
What are the 4 different type of ear mold materials? - CORRECT ANSWER - -acrylic
-silicone
-polyvinyl chloride
-polyethylene
Describe acrylic ear mold material. - CORRECT ANSWER - -very hard and durable
-easy to modify
-easy to insert and remove (dexterity)
-may not get a tight seal
-will not bend or compress for narrow ear canals
-appropriate for most older adult fittings/mild moderate losses
T/F: Acrylic ear molds are typically recommended for children. - CORRECT ANSWER -
FALSE - due to concern for injury if struck while wearing the ear mold
Describe silicone ear mold material. - CORRECT ANSWER - -available in tacky/low
pressure cured and high pressure cured varieties (good for many types of losses)
-most appropriate for children
-most appropriate for severe to profound losses
-fairly hypoallergenic
-difficult to modify due to softness
-most difficult to insert
-tubing adhesives may not stick so may need tube lock
Why are silicone ear molds good for severe to profound hearing loss? - CORRECT
ANSWER - because the mold fits down better in the ear canal and does not create
feedback
,If you had a patient with dexterity issues, what ear mold material would you be most likely to
choose? which would you be least likely to choose? - CORRECT ANSWER - most likely
- acrylic
least likely - silicone
Describe polyvinyl chloride ear mold material. - CORRECT ANSWER - -available in
softer and harder varieties
-more comfortable than acrylic
-good for moderate to severe losses
-not as durable
-can be difficult to modify
-more prone to discoloration
-problematic for patients with vinyl allergies
Describe polyethylene ear mold material. - CORRECT ANSWER - -similar to acrylic but
more prone to feedback
-used the least often
-plastic like appearance
-most hypoallergenic
What are three different ways for naming ear mold styles? - CORRECT ANSWER --
descriptive name
-naming after inventor
-naming after original application
For a severe to profound loss, what is the typical ear mold fitting? - CORRECT
ANSWER - silicone full shell ear mold
, For a mild to moderate hearing loss, what is the typical ear mold fitting? - CORRECT
ANSWER - acrylic skeleton ear mold
What are the 6 typical ear mold styles? - CORRECT ANSWER - -full shell
-half-shell
-skeleton
-canal
-custom open fit (CROS)
-modular earmold plumbing (domes)
A full shell ear mold style is good for what two things? - CORRECT ANSWER - -severe
to profound loss
-children
Describe a skeleton ear mold style. - CORRECT ANSWER - -common and useful for a
wide range of hearing loss
-sometimes modified to remove the middle portion of the ring that fills the concha bowl (semi
skeleton)
-good for fitting people with weird ear anatomy
Describe a canal ear mold style. - CORRECT ANSWER - -good for mild to moderate loss
-does not fit as tight
-retention can be an issue (can add a canal or helix lock)
-choose for someone who has cosmetic issues
Describe a custom open fit ear mold style. - CORRECT ANSWER - -called a CROS style
and is typically only used for a CROS device
-when you need an open fit but have retention or dexterity issues
-many styles with various configurations of the heel, concha, and helix lock portions
