DSL V5 Research Articles

Correlation between Aural/Oral Performance and Fit-to-Target Gain among Children with Moderate-to- Profound Hearing Loss Aged 5–10 Years

Background and Aim: Real-Ear Measurement (REM) enables proper fitting of the hear- ing aids to achieve the required level of amplification. This study aims to investigate the relationship between aural/oral performance and fit-to-target gain of hearing aids in chil- dren with moderate-to-profound hearing loss.
 Methods: This cross-sectional study was conducted on 30 children with moderate-to-pro- found hearing loss aged 5–10 years. First, the parents’ evaluation of aural/oral perfor- mance of children (PEACH) questioanire was completed. Then, REM was performed using digital speech at 50, 65, 80, and 90 dB SPL at 250–8000 Hz to obtain the fit to the desired sensation level, version 5 (DSL v5) target gain.
 Results: A significant negative correlation was found between the total score of the PEACH (51.66) and the fit-to-target gain at high frequencies (r=–0.482, p=0.01). The maximum fit-to-target gain was 77.5 dB for 65 dB SPL at 6000 Hz. Most of the cases (75%) failed to come within ±5 dB of the target gain. There was a significant difference in the fit-to-target gain between low and high frequencies and between high frequencies with similar input levels.
 Conclusion: A negative correlation between aural/oral performance of children with moderate-to-profound hearing loss and fit-to-target gain of their hearing aids may indicate that a low fit-to-target gain can improve their aural/oral performance. Regular use of REM is recommended in prescribing hearing aids to these children.
 Keywords: Children; fit to target gain; hearing loss; aural/oral performance

Task-Dependent Effects of Signal Audibility for Processing Speech: Comparing Performance With NAL-NL2 and DSL v5 Hearing Aid Prescriptions at Threshold and at Suprathreshold Levels in 9- to 17-Year-Olds With Hearing Loss.

Hearing aid fitting formulas intended for the pediatric population can differ by 6 to 25 dB in prescribed output across frequency leading to large variations in aided audibility. Children perceive these differences and have expressed preferences that favor more audibility for quiet speech and less audibility for noisy speech. In this study, the effect of variations in audibility consistent with hearing aid fittings for children was examined. Sixteen children and adolescents (9-17 years) with mild-to-moderate hearing loss participated. Hearing aids programed to National Acoustic Laboratories or Desired Sensation Level v5.0a targets were fitted to each participant. Also, separate programs with and without a low-level adaptive gain feature were provided with each prescription. Speech reception threshold (SRT) was measured as well as performance for four suprathreshold auditory tasks that increased in cognitive demand. These tasks were word recognition, nonword detection, multiword recall, and rapid word learning. A significant effect of fitting formula, but not low-level or adaptive gain, was observed for SRT. Significant effects of presentation level, fitting formula, and low-level gain were observed for word recognition. The effect of presentation level was significant for nonword detection, multiword recall, and rapid word learning but no other main effects or interactions were significant. Finally, word recognition and nonword detection increased significantly with audibility while multiword recall and word learning did not. The results suggest that audibility assists with the initial perception of auditory input but plays a smaller role in memory formation and learning.

Optimising hearing aid output to paediatric prescriptive targets improves outcomes in children

Objective This study examined the accuracy of hearing aid output to DSL v5.0 Child targets in a group of children who wear hearing aids, and the impact on their auditory outcomes. Design For each participant, the output of the initial hearing aid fitting was compared to DSL v5.0 Child prescriptive targets and again after the fitting was adjusted using coupler-based verification and RECD measures. Outcomes for initial and adjusted fittings were examined using the Speech Intelligibility Index (SII), Parent’s Evaluation of Aural/Oral Performance of Children (PEACH) rating scale, and speech perception tests in quiet and noise. Study sample Sixty-eight children aged 3 months to 17 years with moderate to profound hearing loss participated in the study. Results Fit-to-targets improved significantly after hearing aids were adjusted to match targets to within 5 dB RMSE. Adjusted hearing aids provided increased aided audibility compared to initial fittings and resulted in improved speech perception scores and parent-reported hearing performance. Fifty percent of the children aged 6 to 17 years preferred their adjusted fitting compared to 10% who preferred their initial fitting. Conclusions Improvement in fit-to-target to a validated paediatric prescriptive formula using best practice procedures can result in improved auditory outcomes and possible self-reported satisfaction.

Parent’s and teacher’s evaluation of aural oral performance of children with hearing aids

Background and Aim: Parents' evaluation of aural/oral performance of children (PEACH) and teachers' evaluation of aural/oral performance of children (TEACH) questionnaires are used to assess the behaviors of hearing-impaired children in real-life situations. This study aims to compare the scores of PEACH and TEACH in children with severe-to-profound sensorineural hearing loss (SNHL) using hearing aids. Methods: This is a double-blind two-period crossover study on 21 children aged 9-72 months with severe-to-profound SNHL using hearing aids. There were two 6-week periods of fitting Phonak Naida Venture SP hearing aids using the fifth version of the Desired Sensation Level (DSL v5) and the National Acoustics Laborato­ries’ nonlinear fitting procedure (NAL-NL2) pre­scriptions. At the end of each trial, the PEACH and TEACH questioners were completed through an interview with the parents and teachers, res­pectively. Results: There was a strong correlation between the PEACH and TEACH in total and subscale scores. There was no significant difference bet­ween the results of DSL v5 and the NAL-NL2 prescriptions for the total score and subscale scores of PEACH and TEACH. Conclusion: The PEACH score has a strong correlation with the TEACH score. These ques­tionnaires are useful tools for indirectly assess­ment of hearing-impaired children’s communi­cation skills. The DSL v5 and the NAL-NL2 prescriptions make no significant difference in the performance of children with severe-to-profound SNHL. Keywords: Aural oral performance; questionnaire; children; parents; hearing loss; functional performance

Speech recognition, loudness, and preference with extended bandwidth hearing aids for adult hearing aid users

Objective: In contrast to the past, some current hearing aids can provide gain for frequencies above 4–5 kHz. This study assessed the effect of wider bandwidth on outcome measures using hearing aids fitted with the DSL v5.0 prescription.Design: There were two conditions: an extended bandwidth condition, for which the maximum available bandwidth was provided, and a restricted bandwidth condition, in which gain was reduced for frequencies above 4.5 kHz. Outcome measures were assessed in both conditions.Study sample: Twenty-four participants with mild-to-moderately-severe sensorineural high-frequency sloping hearing loss.Results: Providing extended bandwidth resulted in maximum audible output frequency values of 7.5 kHz on average for an input level of 65 dB SPL. An improvement in consonant discrimination scores (4.1%), attributable to better perception of /s/, /z/, and /t/ phonemes, was found in the extended bandwidth condition, but no significant change in loudness perception or preferred listening levels was found. Most listeners (79%) had either no preference (33%) or some preference for the extended bandwidth condition (46%).Conclusions: The results suggest that providing the maximum bandwidth available with modern hearing aids fitted with DSL v5.0, using targets from 0.25 to 8 kHz, can be beneficial for the tested population.

Comparison of bimodal benefit for the use of DSL v5.0 and NAL-NL2 in cochlear implant listeners

Objective: For a group of bimodal subjects with moderate to severe hearing loss contralateral to the cochlear implant (CI), the bimodal benefit of the hearing aid (HA) gain prescriptions DSL v5.0, NAL-NL2 and the recipients’ own gain setting were assessed.Design: Speech perception in quiet and in noise as well as self-reported ratings of benefit were determined for all three gain-settings. Speech tests were performed in the bimodal, the HA alone and the CI alone condition. The bimodal benefit was assessed for each prescription as the difference score of the bimodal condition and the better ear.Study Sample: Twenty adults with post-lingual hearing loss.Results: Speech perception with DSL v5.0 was significantly higher compared to NAL-NL2 and the own prescription in both quiet and noise. The median bimodal benefit was highest for DSL v5.0 with an average of 15 percentage points for both words in quiet and sentences in noise.Conclusions: DSL v5.0 and NAL-NL2 are both suitable for HA fitting in bimodal users. For subjects with moderate to severe hearing loss and HA experience contralateral to the implanted side, DSL v5.0 may provide better speech perception and bimodal benefit.

Gain adjustment at tinnitus pitch to manage both tinnitus and speech perception in noise

To investigate how much gain variation is required from prescription to effect tinnitus percept, and if this revised prescription affects speech recognition. Twenty participants who experienced catastrophic tinnitus even after fitted with hearing aid were included. Participants were grouped based on their tinnitus pitch and the prescriptive formula used to fit hearing aid. They were evaluated for handicap from tinnitus using Tinnitus Handicap Inventory (THI). Hearing aid was programmed using either NAL- NL2 or DSL (I/o) v5 prescriptive formula and gain at tinnitus pitch was adjusted till the tinnitus get suppressed. SNR 50 was determined soon after fitted with hearing aid and 30 days of hearing aid use. Further, THI and international outcome inventory for hearing aid (IOI-HA) were determined after 30 days of hearing aid use. A significant higher gain adjustment was needed at tinnitus pitch to reduce tinnitus precept using NAL- NL2 than DSL (I/o) v5 prescriptive formula. Further, SNR 50 was not affected by either tinnitus pitch or revised prescription formulas. However, SNR 50 improved after 30 days of hearing aid use. A 76% of the participants’ experienced habituation to perception after 30 days of hearing aid use, 10% had slight, 10% had mild, and 4% had a moderate degree of tinnitus on THI. On IOA-HA, 96% (N=19) of participants have reported satisfactory, and 4% (N=1) reported moderate benefit from hearing aid. Irrespective of prescriptive formula adjusting gain at tinnitus pitch is an efficient method to reduce tinnitus symptoms and improve speech perception.

Comparative study of auditory brainstem response and auditory steady-state response as an objective measure for hearing aid verification

Introduction: Hearing aid benefit could be measured objectively by electrophysiological tests. Objective measures are important for hearing assessment in individuals who are unable to provide behavioural responses to reach optimal hearing aids fitting verification.Purpose: This study was designed to compare the Functional Gain (FG) of Auditory Steady State Response (ASSR) and Tone Burst Auditory Brainstem Response (TB ABR) as objective tools with the subjective FG using sound field pure tone audiometry (PTA) in adult patients with sensorineural hearing loss using two hearing aid fitting formulae; DSL v5 and NAL-NL2.Material and methods: This study included twenty hearing-impaired adults, their hearing thresholds ranged from moderate to moderately severe sensorineural hearing loss with flat or gradually falling configuration. Their age ranged from eighteen to sixty years. Subjects were examined in three scheduled sessions; unaided, aided NAL-NL2 and aided DSL V5. Each session included free field PTA, TB ABR and ASSR testing at four tested frequencies 500, 1000, 2000 and 4000 Hz.Results: The mean difference between free field PTA FG and TB ABR FG was 6.02 ± 5.11 and 6.51 ± 4.53 by NAL-NL2 and DSL v5 respectively. The cumulative percentage of cases who had mean total differences within ±2 SD (< ±15 dB) was 100% in both formulae. The mean difference between free field PTA FG and ASSR FG was 2.00 ± 7.48 and 2.00 ± 6.99 by NAL-NL2 and DSL v5 formulae respectively. The cumulative percentage of cases who had mean total differences within ±2 SD (< ±15 dB) was 90% in NAL-NL2 formula and 95% in DSL v5 formula. When using identical test conditions and the same type of stimulus, NAL-NL2 and DSL v5 revealed similar functional gain measurements.Conclusions: Both TB ABR and ASSR are valuable objective measures for thresholds detection. The FG measured by TB ABR and ASSR could be applied as an objective tool for hearing aid fitting verification in hearing impaired individuals.

Fit-to-Targets for the Desired Sensation Level Version 5.0a Hearing Aid Prescription Method for Children.

The purpose of this study was to measure the range of fit to Desired Sensation Level version 5.0 (DSL v5.0) targets in pediatric practice environments. Results will be used in the future to develop clinical-aided speech intelligibility index typical performance data. Clinical partners collected data from 161 final hearing aid settings for children aged ≤ 10 years. Measured data were obtained by performing 2-cm3 coupler-simulated real-ear measurements using the DSL v5.0 implementation on the Audioscan VF-1 (Etymonic Design Inc., Dorchester, ON, Canada) for soft, average, and loud speech inputs and maximum hearing aid output levels. Fittings were within ± 5-dB root-mean-square (RMS) error of target for 77%, 80%, and 82% of fittings for the soft, medium, and loud speech test levels, respectively. Aided maximum power output measures were within ± 5-dB RMS error in 72% of cases. Degree of hearing loss, test frequency, and frequency by test level were significant factors in deviation from target. The range of aided speech intelligibility index values exhibited a strong correlation with the hearing levels of the children tested. This study provides evidence that typical hearing aid fittings for children can be achieved within ± 5-dB RMS error of the DSL v5.0 target. Greater target deviations were observed at extreme frequencies and as the severity of hearing loss increased.

The Effects of Digital Signal Processing Features on Children's Speech Recognition and Loudness Perception

The purpose of this study was to determine the effects of hearing instruments set to Desired Sensation Level version 5 (DSL v5) hearing instrument prescription algorithm targets and equipped with directional microphones and digital noise reduction (DNR) on children's sentence recognition in noise performance and loudness perception in a classroom environment. Ten children (ages 8-17 years) with stable, congenital sensorineural hearing losses participated in the study. Participants were fitted bilaterally with behind-the-ear hearing instruments set to DSL v5 prescriptive targets. Sentence recognition in noise was evaluated using the Bamford-Kowal-Bench Speech in Noise Test (Niquette et al., 2003). Loudness perception was evaluated using a modified version of the Contour Test of Loudness Perception (Cox, Alexander, Taylor, & Gray, 1997). Children's sentence recognition in noise performance was significantly better when using directional microphones alone or in combination with DNR than when using omnidirectional microphones alone or in combination with DNR. Children's loudness ratings for sounds above 72 dB SPL were lowest when fitted with the DSL v5 Noise prescription combined with directional microphones. DNR use showed no effect on loudness ratings. Use of the DSL v5 Noise prescription with a directional microphone improved sentence recognition in noise performance and reduced loudness perception ratings for loud sounds relative to a typical clinical reference fitting with the DSL v5 Quiet prescription with no digital signal processing features enabled. Potential clinical strategies are discussed.

Prescription of hearing-aid output for tinnitus relief

Objective: Tinnitus is a perceived sound that cannot be attributed to an external source. This study attempts to identify a prescription of amplification that is optimized as a first-fit setting for tinnitus relief. Design: Participants compared the effect of high frequency amplification on their tinnitus. Stimuli were 13 speech files with different amounts of high frequency amplification (three cut-off frequencies and four gain settings) to simulate the effects of a change in DSL(I/O) v5.0 prescription in the high frequencies. Study sample: Twenty-five participants with chronic tinnitus participated in the study. Results: A 6-dB reduction to prescribed gain at 2 kHz emerged as the most preferred output (26.47% participants) to interfere with participants’ tinnitus. Overall, 70.58% of the participants’ preferred a 3 to 6 dB reduction in output while 29.42% preferred a similar increase across all cut-off frequencies. A trend was observed in which the higher the tinnitus pitch the more similar the preferred output to DSL(I/O) v5.0. Conclusion: DSL(I/O) v5.0 appears to be a good starting point for prescription of hearing-aid output for tinnitus management. Long-term benefits of different prescriptions for tinnitus still need to be ascertained.

Evaluation of real-world preferences and performance of hearing aids fitted according to the NAL-NL1 and DSL v5 procedures in children with moderately severe to profound hearing loss

Objective: The study aims to compare the performance of hearing aids fitted according to the NAL-NL1 and DSL v5 prescriptive procedure for children. Design: This is a crossover four period trial. Study sample: Sixteen school-aged children with moderately severe to profound hearing losses participated in the study. The children were fitted with Phonak Naida V SP hearing aids according to the two prescriptive procedures. Results: The results showed that children performed significantly better with DSL v5 than with NAL-NL1 prescription for sentence perception in quiet. The paired-comparison judgments of speech intelligibility showed seven children significantly preferred the DSL v5 prescription while two children preferred the NAL-NL1 prescription. The average scores on functional and ratings by parents and teachers performance of children in real life were significantly better for the DSL v5 prescription. At the end of all trials, nine children preferred the DSL v5 prescription, four preferred the NAL-NL1 prescription, and two had no preference. Conclusions: Hearing aids fitted based on the DSL v5 procedure would seem to be more appropriate than the NAL-NL1 procedure for children with moderately severe to profound sensorineural hearing loss, at least in quiet listening environments.

Cochlear Implantation in Children with Auditory Neuropathy Spectrum Disorder: Long-Term Outcomes

Best practices concerning the audiological management of the child diagnosed with auditory neuropathy spectrum disorder (ANSD) have not been definitively defined nor fully understood. One reason is that previous studies have demonstrated conflicting findings regarding the outcomes of cochlear implantation for children with ANSD. Thus, the question remains whether children with ANSD are able to achieve similar outcomes following cochlear implantation as those children with sensorineural hearing loss (SNHL). To assess speech perception outcomes for children with cochlear implants who have a diagnosis of ANSD as well as their age-matched peers who have sensorineural hearing loss. Retrospective study Thirty-five subject pairs (n = 70) ranging in age at implant activation from to 10 to 121 mo (mean 39.2 mo) were included in this retrospective study. Subjects were matched on variables including age at initial implant activation and months of implant use at postoperative test point. Speech recognition scores for monosyllabic and multisyllabic stimuli were compared across the subject groups. For those not developmentally and/or linguistically ready for completion of open-set speech recognition testing with recorded stimuli, GASP (Glendonald Auditory Screening Procedure) word recognition and/or questionnaire data using either the LittlEARS or Meaningful Auditory Integration Scale were compared across the groups. Statistical analysis using a repeated-measures analysis of variance (ANOVA) evaluated the effects of etiology (ANSD or SNHL) on postoperative outcomes. The results of this study demonstrate that children with ANSD can clearly benefit from cochlear implantation and that their long-term outcomes are similar to matched peers with SNHL on measures of speech recognition. There were no significant differences across the ANSD and SNHL groups on any of the tested measures. Cochlear implantation is a viable treatment option for children with a diagnosis of ANSD who are not making auditory progress with hearing aids that have been fit using the Desired Sensation Level method (DSL v5.0). Expected outcomes of cochlear implantation for children with ANSD, excluding children with cochlear nerve deficiency, are no different than for children with non-ANSD SNHL. These results are important for counseling families on the expected outcomes and realistic expectations following cochlear implantation for children with ANSD who demonstrate no evidence of cochlear nerve deficiency.

Fit to targets, preferred listening levels, and self-reported outcomes for the DSL v5.0a hearing aid prescription for adults

Study objective: This study evaluated how closely the DSL v5.0a prescription could be approximated with hearing aids, its relationship to preferred listening levels (PLLs) of adults with acquired hearing loss, and the self-reported outcomes of the resulting fittings. Participants: Thirty adults with varying degrees and configurations of hearing loss ranging from mild to severe. Methods: Hearing aid output was measured after the initial fitting to DSL v5.0a targets and after determination of the PLL after approximately 90 days. The Client Oriented Scale of Improvement (COSI) was used to evaluate outcome. Results: The 95% confidence interval of fits to target ranged from 5.8 to 8.4 dB across frequency. The DSL v5.0a adult algorithm approximated the PLLs of the participants within 2.6 dB on average. Hearing aid fittings provided positive subjective outcome improvements on the COSI. Conclusions: Findings suggest that the use of DSL v5.0a for the fitting of hearing aids on adults with acquired hearing loss was feasible and provided an appropriate initial fitting.SumarioObjetivo del estudio: Este estudio evaluó qué tanto puede satisfacer una prescripción DSL v5.0a con auxiliares auditivos, su relación con los niveles preferidos de escucha (PLLs) en adultos con pérdida auditiva adquirida y los resultados de los auto reportes de las adaptaciones resultantes. Participantes: Treinta adultos con variados grados y configuraciones de pérdidas auditivas, entre leves y severas. Métodos: Se midió la salida del auxiliar auditivo después de la adaptación por metas DSL v5.0a y después de determinar los PLL, al cumplirse aproximadamente 90 días. Para evaluar los resultados, se usó la Escala de Mejoría Orientada hacia el Cliente (COSI). Resultados: 95% de intervalo de confianza de adaptaciones relacionadas con blancos, entre 5.8 a 8.4 dB en todas las frecuencias. El algoritmo en adultos del DSL v5.0a se aproximó a los PLLs de los participantes en un promedio de 2.6 dB. Las adaptaciones de auxiliares auditivos dieron resultados subjetivos positivos con el COSI. Conclusiones: los hallazgos sugieren que el uso de DSL v5.0a para la adaptación de auxiliares auditivos en adultos con pérdidas auditivas adquiridas fue factible y permitió una adaptación inicial apropiada.

Reflections on 40 Years of Amplification

Reflections on 40 Years of Amplification

Considerations in early amplification: Selection, fitting, validation, counseling

The implementation of universal newborn hearing screening programs has increased the number of infants diagnosed with hearing loss and referred for amplification in the first few weeks of life. There is compelling evidence that children born with hearing loss who have been identified and begun intervention by 6 months of age will have significantly better language development than their later-identified peers. 1-3 The challenges of fitting appropriate amplification on this population include limited behavioral response to sound, possible complicating middle ear fluid, parental uncertainties, possible existence of additional handicaps, and limited resources to support and pay for hearing aids. Despite these issues, there is consensus that the diagnosis of congenital hearing loss should be completed in the first 3 months of life and be followed immediately with the consideration of hearing aid use. 4 As access to follow-up from newborn hearing screening improves, pediatric audiologists are faced with recommending technology for infants during their early weeks of life. The options available to them are expanding rapidly as amplification technology grows and diversifies. Outcome studies of children fitted with advanced amplification features are not common and cannot keep up with the features being introduced to the market. Most infants are fitted with the goal of providing audibility for environmental speech to enhance speech and language development and with the expectation that patients will use their hearing aids daily. The pediatric audiologist’s role is to share information on hearing loss and available amplification technology with the parents and their medical and support team. Parents depend on various professionals to acquire the information and tools they need to become empowered, informed consumers. Reaching decisions about the choice of technology for an infant includes examining available features and selecting what might be the best fit for the infant given all the available information and circumstances.

Audiologists Join SLPs at Schools Conference

Audiologists Join SLPs at Schools Conference

Pediatric hearing aid fittings and DSL v5.0

Pediatric hearing aid fittings and DSL v5.0

The DSL method

Page Ten September 2006 • Vol. 59 • No. 9 O kay, here’s a little quiz for you older readers. Imagine this scenario: You’re driving your newly released Ford Taurus, drinking your first can of New Coke, listening to We Are The World on the radio on your way to the movie Back to the Future. And the year was? That’s right,1985. If you were fitting hearing aids back then, you probably sat down at your newly purchased probe-mic equipment and became a little overwhelmed at the prescriptive fitting options. On this equipment alone there was the Lybarger 1/2-gain, the Berger method, and POGO. But wait, you also just read about the Libby 1/3-gain method and a year or so ago you learned about Pascoe’s research and Cox’s MSU procedure. And then there was this Australian fitting method that people were starting to talk about. It was all so confusing. But something else was happening on the prescriptive fitting front in 1985 that only a few people noticed. A fellow named Richard Seewald, writing in Ear and Hearing, introduced a new procedure for children called the Desired Sensation Level method, or simply DSL. While most of the prescriptive methods of the 1980s are now long forgotten, the DSL has become the standard for pediatric amplification and is one of the few validated prescriptive methods in use today. The procedure and the software have evolved over the years, and another revised version is being launched this year. We’re pleased to celebrate the DSL’s 21st birthday here on Page Ten, and provide you with a preview of the DSL v5.0 prescriptive fitting procedure. Our Page Ten author this month is Susan Scollie, PhD, assistant professor at the National Centre for Audiology and the School of Communication Sciences and Disorders, Faculty of Health Sciences, at theUniversity of Western Ontario. Dr. Scollie also serves as co-director of the Child Amplification Laboratory at the Centre. In addition to her previous contributions here on Page Ten, you probably know Susan from her many publications in the area of hearing aid selection and fitting. She also has conducted workshops worldwide on hearing aid fittings for infants and children, and serves on several related committees. On the next few pages, Dr. Scollie describes the new features of DSL v5.0 and provides a review of the supporting research. While the introduction of New Coke didn’t fare very well back in 1985, the flavor of the DSL always has been tasty, and it just keeps getting better. For that, many audiologists and hearing-impaired children and parents are thankful.