May 2020 The Hearing Journal
Hearing technology and best practices in hearing health care are constantly evolving. On one hand, advances in paediatric audiology are great because they allow children with hearing loss to achieve better listening and spoken language outcomes. However, the constant evolution in hearing aids, implantable hearing technologies, wireless accessories, diagnostic measures, and clinical intervention can make it difficult for clinicians to keep up with updates in science and technology. Clinicians can certainly access new information at professional meetings, through online platforms, and on social media, but most of the latest information that drives evidence-based practice continues to be found in the peer-reviewed literature. Here's a brief review of some of our favourite publications in paediatric hearing health care in 2019.
10. Addressing Mild and Unilateral Hearing Loss: What do families want?
Many clinicians are hungry for evidence-based recommendations for the optimal care for children with mild and unilateral hearing loss (UHL). A great place to start is understanding the needs of families of children with these conditions. Fitzpatrick, et al. sought to identify the services that were most coveted by the families of children with mild and UHL, and found that families greatly preferred enhanced support for speech and language development. Specifically, families desired formal speech and language assessments to ensure that their children were making satisfactory progress. They also wanted direct speech and language therapy to facilitate optimal development of language abilities. Families also expressed support for amplification use and consistent communication with professionals. For amplification support, many families preferred a combination of regular clinic visits (for audiology assessments and hearing aid checks) along with periodic phone calls or emails from the clinician to inquire about hearing aid use and offer support as needed. Of note, however, families were twice as likely to want support for speech and language development than for amplification use.
9. Guidelines for Serving Children with UHL
Bagatto and colleagues developed an excellent summary of principles to be considered in the management of children with UHL. Following a 2017 conference on the assessment and management of children with UHL, an international panel of experts on the topic met to develop practice parameters and detailed guidelines to assist clinicians in providing individualised, best-practice services for children with hearing loss. The summary by Bagatto, et al. of these guidelines includes pros, cons, and clinical considerations for various hearing technologies available for children with UHL. The authors also provided a flowchart to help professionals determine a clinical care plan for these children.
8. Remote Mic Use for Pre-Schoolers at Home
Benitez-Barrera, et al. systematically evaluated the potential benefits of remote microphone use by caregivers of preschool children with hearing loss. They studied remote microphone use in the homes of 10 children with hearing loss, and found that 57 percent of conversations at home were directed toward the child (i.e., child-directed speech [CDS]). Twelve percent of CDS occurred when the caregiver was at least six to 10 feet away from the child, and as a result, it is likely that the CDS would have been unavailable to the child without the use of a remote microphone system. The researchers noted that use of the remote microphone did not change the amount of CDS that occurred in the homes of children with hearing loss. However, it did significantly improve access to CDS. Noting that intelligible speech is the fertiliser that grows the auditory areas of the brain, remote microphone use should be considered by all families of children with hearing loss.
7. Functional Near-Infrared Spectroscopy: A Window into Auditory Brain Development?
Functional near-infrared spectroscopy (fNIRS) is an imaging technique that can be used to measure cortical activity during rest and/or while a participant is exposed to different stimuli (e.g., auditory, visual, tactile, etc.). Source optodes are used to deliver infrared light into the head and to measure the amount of light that returns to detector optodes. Oxygenated blood is delivered to active regions of the brain. The infrared light is absorbed by oxygenated blood, so a reduction in infrared light returning to the detector optode infers activity in the region of the brain underlying the optodes. Heather Bortfield provided an excellent overview of the fundamentals of fNIRS assessment and the potential advantages and limitations associated with the use of fNIRS in a study of auditory brain function of individuals with hearing loss. She also provided a review of recent studies that have used fNIRS to evaluate the brain function of individuals with hearing loss. Although the potential clinical applications of fNIRS have yet to be fully determined, it serves as a promising tool to evaluate the auditory function of children with hearing loss. Paediatric hearing health care professionals are likely to enjoy Bortfield's review of this new and exciting technology.
6. Listening Effort of Children with Hearing Loss in Complex Situations
McGarrigle, et al. published their latest update in a line of studies by researchers from Vanderbilt University exploring listening effort and fatigue in children with hearing loss. They studied listening effort by measuring verbal response time (VRT) during speech-recognition-in-noise testing and the ability to monitor a visual stimulus during speech recognition-in-noise assessment (i.e., dual-task paradigm). Children with hearing loss showed longer VRT than children with normal hearing, which is yet more evidence of higher-order processing deficits in children with hearing loss. McGarrigle and colleagues found that these processing deficits may hamper a child's ability to succeed in the classroom. Interestingly, the use of amplification did not improve the response time of children with hearing loss. They noted a need for additional research exploring the potential benefits of noise management technologies (e.g., directional microphones, digital noise reduction, remote microphone system) on the listening effort of children with hearing loss. Gustafson, et al. previously reported faster VRT when children used digital noise reduction. Given the finding of increased listening effort for children with hearing loss in noisy situations, audiologists should consider noise management technologies for paediatric hearing aid users.
5. American Academy of Audiology Cochlear Implant (CI) Guidelines
There is a paucity of professional guidelines for the management of individuals with a CI. This past year, the American Academy of Audiology (AAA) took a big step toward filling that void with the publication of “Clinical Practice Guidelines for Cochlear Implants,” which provides an exhaustive review of all aspects of CI management, including candidacy, signal coding and processing, programming, outcomes assessment, medical considerations, billing, etc. The document, which is free regardless of AAA membership, cites numerous peer-reviewed studies to support its recommendations for clinical management, and provides an indication of the strength of the evidence supporting each recommendation.
4. First-fit vs. Real-Ear-Probe-Microphone Verification
Folkeard and colleagues from the Childhood Amplification Laboratory at Western University in Ontario evaluated the accuracy of manufacturer-derived first-fit paediatric hearing aid settings relative to desired sensation level (DSL) 5.0 targets for children. They evaluated 13 different behind-the-ear hearing aids from eight different manufacturers set for a six-month-old test case with audiograms ranging from mild to profound. Most hearing aids with first-fit settings for mild to moderate hearing loss were within +/-5 dB of DSL 5.0 prescriptive targets. However, significant (i.e., > 5 dB) deviations from target were often observed when first-fit settings were used for hearing aids programmed for severe to profound hearing loss. They concluded that clinicians will likely need to complete individualised probe microphone verification measures with measured real-ear-to-coupler differences to optimise fit-to-target and aided speech intelligibility index for each child, regardless of the degree of hearing loss and individual differences in ear anatomy.
3. CI Use and Spoken Language Outcomes
Park and colleagues at the University of North Carolina studied the effects of age at cochlear implantation and the amount of CI use per day on the language outcomes of 40 children at 3 years of age. They quantified the amount of CI use per day based on the percentage of time the child used the CI during waking hours and accounted for the fact that younger children slept more and consequently had fewer waking hours. They reported that age at implantation was poorly associated with language outcomes, whereas the percentage of CI use during waking hours was a strong predictor of language outcomes. They noted that early access to speech is not possible without early implantation, but also acknowledged that the benefits of early implantation are limited if families do not achieve full-time CI use (defined as CI use for at least 80% of waking hours). Unfortunately, only about one-half of participants had achieved full-time CI use by 3 years of age. Paediatric hearing health care providers must support all families in achieving full-time use immediately after implantation.
2. JCIH Position Statement
The outcomes of children born with hearing loss are intimately tied to the success of early hearing detection and intervention (EHDI) programs. The guiding beacon for EHDI service provision is the Joint Commission on Infant Hearing (JCIH) Position Statement. The 2019 JCIH Position Statement includes many important updates on the last statement published in 2007. For instance, the 2019 guideline encourages U.S. states to strive for 1-2-3: (1) hearing screening completed by 1 month of age, (2) diagnostic assessment completed by 2 months of age, and 3) intervention provided by 3 months of age. The JCIH also reaffirms the importance of well-designed, evidence-based screening and assessment protocols, as well as hearing aid fitting methods. The JCIH notes that OAE re-screening is acceptable for well-born infants who initially did not pass an ABR screening only because the incidence of auditory neuropathy spectrum disorder is low in the well-baby nursery. The 2019 JCIH statement is a must-read for health care professionals who serve children at risk for hearing loss.
1. Early Ears
Hoff and colleagues added to the mounting body of evidence proving the critical benefits of cochlear implantation prior to 12 months of age for children with severe to profound hearing loss. They reported no differences in medical complications or anaesthetic morbidities in children implanted before turning 12 months old relative to those implanted later. Furthermore, children implanted before 12 months of age achieved open-set speech recognition at an earlier age than those implanted after 12 months of age. Perhaps most startling, only 48 percent of children implanted after 12 months of age communicated via oral language alone, compared with 88 percent of children implanted prior to 12 months of age. This should be shared with health care policymakers and third-party payers to make implantation available well before the first birthday of children with severe to profound hearing loss.