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A Comparison Between Wireless CROS and Bone-anchored Hearing Devices for Single-Sided Deafness: A Pilot Study

A Comparison Between Wireless CROS and Bone-anchored Hearing Devices for Single-Sided Deafness: A Pilot Study

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT01715948
Enrollment
9
Registered
2012-10-29
Start date
2013-01-31
Completion date
2013-10-31
Last updated
2016-04-05

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Unilateral Deafness, Unilateral Hearing Loss

Keywords

CROS hearing aid, Bone-anchored hearing device

Brief summary

People with single-sided deafness (SSD) have significant hearing loss in one ear and normal or near normal hearing in the other ear. Those living with SSD experience several communication difficulties, particularly when listening to speech in the presence of background noise. This problem is worse in situations where the noise is on the side of the good ear and the speech is on the side of the poor ear. The Bone-anchored hearing device (BAHD) and the Contralateral Routing of Signals (CROS) hearing aid are two intervention methods designed to improve hearing in people who have significant hearing loss in one ear only. The BAHD is a surgically implanted device which also includes an external processor; sounds from the poor ear are transmitted to the good ear through skull vibrations. The CROS does not involve surgery; instead a hearing aid is fitted behind each ear, and the sounds on the side of the poor ear are wirelessly transmitted to the good ear. The majority of previous studies comparing the BAHD to the CROS have used older CROS models with basic technology and a wire along the neck to send sounds from the poor ear to the good ear. There is a lack of studies comparing newer digital wireless CROS hearing aids to the BAHD. The current research will compare the effect of the BAHD and CROS hearing aid on speech perception scores when listening to speech in quiet and in noise. The research will also investigate participants' reported benefits with each device during everyday situations. In order to compare the BAHD and CROS, individuals who already have been implanted with a BAHD will be given a trial period with a new wireless digital CROS hearing aid. The research hypothesis states that the CROS hearing aid will be as equally beneficial or greater than the BAHD in improving hearing and participant benefit. If the findings support the hypothesis that the CROS offers just as much benefits as the BAHD, or is an even better alternative, more individuals with SSD may choose to avoid surgery and decide to receive a CROS hearing aid instead.

Detailed description

Users of the BAHD will be given a 2-week trial period with the Unitron Tandem CROS hearing aid. Participants will be randomly assigned to wear either their BAHD for two weeks or the trial CROS for two weeks. There will be a total of three visits made to the clinic. During each visit: * Participants' hearing will be tested (either with the BAHD, the CROS, or without wearing any device). * Speech perception ability will be tested in quiet and in noise conditions (either while wearing the BAHD, the CROS, or no device). * Participants will be asked to complete two standardized questionnaires on the perceived benefits that the BAHD or the CROS provides. In addition, participants will be asked to fill out a short diary form every day, for a two-week period, to report the situations in which they wore the device.

Interventions

DEVICEBone-anchored hearing device (BAHD)

All participants had received BAHD implantation prior to the study. They were randomly selected to continue wearing their BAHD for 2 weeks following the end of the first visit or the end of the second visit. Both devices were compared on head shadow effect reduction, speech perception measures in quiet and in noise, self-assessment questionnaires, and daily diaries.

DEVICECROS hearing aid

Participants were randomly assigned to be fitted with the CROS hearing aid either at the end of the first visit or at the end of the second visit. They were given a 2-week trial with the CROS and asked to refrain from wearing their BAHD during that time. At the end of the first visit, four participants were fitted with the CROS hearing aid and were subsequently tested with this device on their second visit, at which time they were instructed to use the BAHD for the next 2 weeks. This protocol was reversed in the other four participants, with testing after each device experience. Both devices were compared on head shadow effect reduction, speech perception measures in quiet and in noise, self-assessment questionnaires, and daily diaries.

Sponsors

Dalhousie University
CollaboratorOTHER
Manohar Bance
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes

Inclusion criteria

* Adults with unilateral deafness (hearing loss in only one ear) who received BAHD surgery less than 3 years ago * Severe to profound hearing loss in the poor ear and normal hearing in the good ear * English speaking

Exclusion criteria

* Adults who underwent BAHD surgery more than 3 years ago * Adults with hearing loss in both ears * Adults who received a BAHD to treat a condition other than unilateral deafness (such as bilateral conductive hearing loss)

Design outcomes

Primary

MeasureTime frameDescription
Number of 5 Key Words Within 6 Sentence Lists Repeated Correctly in the Presence of Multitalker NoiseThe QuickSIN unaided was administered at baseline, an average of 2 weeks (with CROS or BAHD) and an average of 4 weeks (with opposite device not previously tested).One speech-in-noise test (QuickSIN) presented four lists of six pre-recorded sentences at 50 dB hearing level (HL) in soundfield. Multitalker noise was presented together with the target sentence and increased at a fixed number of dB with the completion of each sentence. The multitalker noise was initially presented at 25 dB HL (signal-to-noise ratio - SNR of 25 dB), and increased by 5 dB after each sentence until the multitalker noise was of equal intensity with the final sentence (SNR of 0 dB). In one condition, two lists of sentences were presented to the participant at 0 degrees with the multitalker noise delivered at 90 degrees to the poor ear. In the other condition, two different lists of sentences were presented to the participant at 0 degrees with the multitalker noise delivered at 90 degrees to the better ear. The two scores derived from the two different lists of sentences presented within each condition were averaged. A low score indicates better performance.
Percentage of Words RecognizedWord recognition testing (unaided) occurred at baseline, an average of 2 weeks (with CROS or BAHD) and an average of 4 weeks (with opposite device not previously tested)..Word recognition was tested with the recorded version of the Central Institute for the Deaf (CID) W-22 (Auditec of St. Louis), with a different list of 25 monosyllabic words presented at 50 dB HL in three randomized listening conditions. In the first condition, one list was presented at 50 dB HL at 90 degrees to the poor ear in quiet. In the second condition, the words were presented at 50 dB HL at 0 degrees while multitalker noise was presented at 45 dB HL at 90 degrees to the poor ear. In the final condition, the words were presented at 50 dB HL at 0 degrees while multitalker noise was delivered at 45 dB HL at 90 degrees to the better ear.
Speech Spatial Qualities Questionnaire (SSQ)Administered at the end of a 2 week trial with the CROS and at the end of a 2 week use of the BAHD.The Speech Spatial Qualities Questionnaire (SSQ) was given to assess the self-perceived benefits provided by the device that was worn the previous 2 weeks. The SSQ requires participants to rate their perceived hearing ability for 49 scenarios using a 10-point scale, ranging from 0 (Not at all) to 10 (Perfectly). A score higher than 0 for each listening scenario shows some benefit of the device, while a score of 10 indicates the device was extremely beneficial. Therefore, a lower score indicated poorer self-perceived benefit from the device (representing a worse outcome), while a higher score indicated greater self-perceived benefit from the device (representing a better outcome). To obtain individual scores for the SSQ questionnaire, the ratings for each listening scenario were summed. The mean, minimum and maximum scores for each subscale of the SSQ across all participants were also determined.

Participant flow

Participants by arm

ArmCount
A Comparison Between Wireless CROS and BAHD for SSD
Participants who have been implanted with a BAHD over the past three years will be given a two-week trial period with a CROS hearing aid. The CROS uses two hearing aids that fit behind each ear. The hearing aid fitted on the side of the poor ear houses a microphone and a transmitter. The hearing aid fitted on the normal ear side houses a receiver that is connected to an open ear tip. Sounds on the side of the poor ear are picked up by the microphone and transmitted to the opposite normal ear, overcoming the head shadow effect that presents with unilateral deafness. CROS hearing aid: BAHD users will be fitted with the CROS hearing aid for a two-week trial period. Their hearing abilities with the CROS hearing aid will be compared to their hearing abilities with their BAHD over a two-week period.
8
Total8

Baseline characteristics

CharacteristicA Comparison Between Wireless CROS and BAHD for SSD
Age, Categorical
<=18 years
0 Participants
Age, Categorical
>=65 years
1 Participants
Age, Categorical
Between 18 and 65 years
7 Participants
Age, Continuous54 years
Region of Enrollment
Canada
8 participants
Sex: Female, Male
Female
7 Participants
Sex: Female, Male
Male
1 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
— / —— / —
other
Total, other adverse events
0 / 90 / 9
serious
Total, serious adverse events
0 / 90 / 0

Outcome results

Primary

Number of 5 Key Words Within 6 Sentence Lists Repeated Correctly in the Presence of Multitalker Noise

One speech-in-noise test (QuickSIN) presented four lists of six pre-recorded sentences at 50 dB hearing level (HL) in soundfield. Multitalker noise was presented together with the target sentence and increased at a fixed number of dB with the completion of each sentence. The multitalker noise was initially presented at 25 dB HL (signal-to-noise ratio - SNR of 25 dB), and increased by 5 dB after each sentence until the multitalker noise was of equal intensity with the final sentence (SNR of 0 dB). In one condition, two lists of sentences were presented to the participant at 0 degrees with the multitalker noise delivered at 90 degrees to the poor ear. In the other condition, two different lists of sentences were presented to the participant at 0 degrees with the multitalker noise delivered at 90 degrees to the better ear. The two scores derived from the two different lists of sentences presented within each condition were averaged. A low score indicates better performance.

Time frame: The QuickSIN unaided was administered at baseline, an average of 2 weeks (with CROS or BAHD) and an average of 4 weeks (with opposite device not previously tested).

ArmMeasureValue (MEAN)
QuickSIN Noise to Better Ear UnaidedNumber of 5 Key Words Within 6 Sentence Lists Repeated Correctly in the Presence of Multitalker Noise5.44 words
QuickSIN Noise to Better Ear With BAHDNumber of 5 Key Words Within 6 Sentence Lists Repeated Correctly in the Presence of Multitalker Noise3.5 words
QuickSIN Noise to Better Ear With CROSNumber of 5 Key Words Within 6 Sentence Lists Repeated Correctly in the Presence of Multitalker Noise4.75 words
QuickSIN Noise to Poorer Ear UnaidedNumber of 5 Key Words Within 6 Sentence Lists Repeated Correctly in the Presence of Multitalker Noise-1.75 words
QuickSIN Noise to Poorer Ear With BAHDNumber of 5 Key Words Within 6 Sentence Lists Repeated Correctly in the Presence of Multitalker Noise0.75 words
QuickSIN Noise to Poorer Ear With CROSNumber of 5 Key Words Within 6 Sentence Lists Repeated Correctly in the Presence of Multitalker Noise2.38 words
Primary

Percentage of Words Recognized

Word recognition was tested with the recorded version of the Central Institute for the Deaf (CID) W-22 (Auditec of St. Louis), with a different list of 25 monosyllabic words presented at 50 dB HL in three randomized listening conditions. In the first condition, one list was presented at 50 dB HL at 90 degrees to the poor ear in quiet. In the second condition, the words were presented at 50 dB HL at 0 degrees while multitalker noise was presented at 45 dB HL at 90 degrees to the poor ear. In the final condition, the words were presented at 50 dB HL at 0 degrees while multitalker noise was delivered at 45 dB HL at 90 degrees to the better ear.

Time frame: Word recognition testing (unaided) occurred at baseline, an average of 2 weeks (with CROS or BAHD) and an average of 4 weeks (with opposite device not previously tested)..

Population: The researchers chose not to include a condition with words presented at 90 degrees to the better ear in quiet.

ArmMeasureGroupValue (MEAN)
QuickSIN Noise to Better Ear UnaidedPercentage of Words RecognizedBAHD Condition62.5 Percentage of words perceived correctly
QuickSIN Noise to Better Ear UnaidedPercentage of Words RecognizedUnaided Condition48.5 Percentage of words perceived correctly
QuickSIN Noise to Better Ear UnaidedPercentage of Words RecognizedCROS Condition62 Percentage of words perceived correctly
QuickSIN Noise to Better Ear With BAHDPercentage of Words RecognizedBAHD Condition77 Percentage of words perceived correctly
QuickSIN Noise to Better Ear With BAHDPercentage of Words RecognizedUnaided Condition78 Percentage of words perceived correctly
QuickSIN Noise to Better Ear With BAHDPercentage of Words RecognizedCROS Condition66.5 Percentage of words perceived correctly
QuickSIN Noise to Better Ear With CROSPercentage of Words RecognizedUnaided Condition96 Percentage of words perceived correctly
QuickSIN Noise to Better Ear With CROSPercentage of Words RecognizedCROS Condition94.5 Percentage of words perceived correctly
QuickSIN Noise to Better Ear With CROSPercentage of Words RecognizedBAHD Condition97 Percentage of words perceived correctly
Primary

Speech Spatial Qualities Questionnaire (SSQ)

The Speech Spatial Qualities Questionnaire (SSQ) was given to assess the self-perceived benefits provided by the device that was worn the previous 2 weeks. The SSQ requires participants to rate their perceived hearing ability for 49 scenarios using a 10-point scale, ranging from 0 (Not at all) to 10 (Perfectly). A score higher than 0 for each listening scenario shows some benefit of the device, while a score of 10 indicates the device was extremely beneficial. Therefore, a lower score indicated poorer self-perceived benefit from the device (representing a worse outcome), while a higher score indicated greater self-perceived benefit from the device (representing a better outcome). To obtain individual scores for the SSQ questionnaire, the ratings for each listening scenario were summed. The mean, minimum and maximum scores for each subscale of the SSQ across all participants were also determined.

Time frame: Administered at the end of a 2 week trial with the CROS and at the end of a 2 week use of the BAHD.

ArmMeasureValue (MEAN)
QuickSIN Noise to Better Ear UnaidedSpeech Spatial Qualities Questionnaire (SSQ)5.56 units on a scale
QuickSIN Noise to Better Ear With BAHDSpeech Spatial Qualities Questionnaire (SSQ)5.79 units on a scale
QuickSIN Noise to Better Ear With CROSSpeech Spatial Qualities Questionnaire (SSQ)4.24 units on a scale
QuickSIN Noise to Poorer Ear UnaidedSpeech Spatial Qualities Questionnaire (SSQ)4.45 units on a scale
QuickSIN Noise to Poorer Ear With BAHDSpeech Spatial Qualities Questionnaire (SSQ)6.89 units on a scale
QuickSIN Noise to Poorer Ear With CROSSpeech Spatial Qualities Questionnaire (SSQ)7.12 units on a scale

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026