Patient‐reported auditory handicap measures following mild traumatic brain injury

Mild Traumatic Brain Injury and the Auditory System: An Overview of the Mechanisms, Clinical Presentations, and Current Diagnostic Modalities

The acute and long-term consequences of mild traumatic brain injury (mTBI) are far reaching. Though it may often be overlooked due to the now expansive field of research dedicated to understanding the consequences of mTBI on the brain, recent work has revealed that substantial changes in the vestibulo-auditory system can also occur due to mTBI. These changes, termed "labyrinthine" or "cochlear concussion," include hearing loss, vertigo, and tinnitus that develop after mTBI in the setting of an intact bony labyrinthine capsule (as detected on imaging). In the review that follows, we focus our discussion on the effects of mTBI on the peripheral structures and pathways of the auditory and vestibular systems. Although the effects of indirect trauma (e.g., noise and blast trauma) have been well-investigated, there exists a profound need to improve our understanding of the effects of direct head injury (such as mTBI) on the auditory and vestibular systems. Our aim is to summarize the current evidentiary foundation upon which labyrinthine and/or cochlear concussion are based to shed light on the ways in which clinicians can refine the existing modalities used to diagnose and treat patients experiencing mTBI as it relates to hearing and balance.

Associations Between Auditory Working Memory, Self-Perceived Listening Effort, and Hearing Difficulty in Adults With Mild Traumatic Brain Injury

OBJECTIVES

Mild traumatic brain injury (TBI) can have persistent effects in the auditory domain (e.g., difficulty listening in noise), despite individuals having normal pure-tone auditory sensitivity. Individuals with a history of mild TBI often perceive hearing difficulty and greater listening effort in complex listening situations. The purpose of the present study was to examine self-perceived hearing difficulty, listening effort, and performance on an auditory processing test battery in adults with a history of mild TBI compared with a control group.

DESIGN

Twenty adults ages 20 to 53 years old participated divided into a mild TBI (n = 10) and control group (n = 10). Perceived hearing difficulties were measured using the Adult Auditory Processing Scale and the Hearing Handicap Inventory for Adults. Listening effort was measured using the National Aeronautics and Space Administration-Task Load Index. Listening effort ratings were obtained at baseline, after each auditory processing test, and at the completion of the test battery. The auditory processing test battery included (1) dichotic word recognition, (2) the 500-Hz masking level difference, (3) the Listening in Spatialized Noise-Sentences test, and (4) the Word Auditory Recognition and Recall Measure (WARRM).

RESULTS

Results indicated that individuals with a history of mild TBI perceived significantly greater degrees of hearing difficulty and listening effort than the control group. There were no significant group differences on two of the auditory processing tasks (dichotic word recognition or Listening in Spatialized Noise-Sentences). The mild TBI group exhibited significantly poorer performance on the 500-Hz MLD and the WARRM, a measure of auditory working memory, than the control group. Greater degrees of self-perceived hearing difficulty were significantly associated with greater listening effort and poorer auditory working memory. Greater listening effort was also significantly associated with poorer auditory working memory.

CONCLUSIONS

Results demonstrate that adults with a history of mild TBI may experience subjective hearing difficulty and listening effort when listening in challenging acoustic environments. Poorer auditory working memory on the WARRM task was observed for the adults with mild TBI and was associated with greater hearing difficulty and listening effort. Taken together, the present study suggests that conventional clinical audiometric battery alone may not provide enough information about auditory processing deficits in individuals with a history of mild TBI. The results support the use of a multifaceted battery of auditory processing tasks and subjective measures when evaluating individuals with a history of mild TBI.

Comprehensive behavioral and physiologic assessment of peripheral and central auditory function in individuals with mild traumatic brain injury

Auditory complaints are frequently reported by individuals with mild traumatic brain injury (mTBI) yet remain difficult to detect in the absence of clinically significant hearing loss. This highlights a growing need to identify sensitive indices of auditory-related mTBI pathophysiology beyond pure-tone thresholds for improved hearing healthcare diagnosis and treatment. Given the heterogeneity of mTBI etiology and the diverse peripheral and central processes required for normal auditory function, the present study sought to determine the audiologic assessments sensitive to mTBI pathophysiology at the group level using a well-rounded test battery of both peripheral and central auditory system function. This test battery included pure-tone detection thresholds, word understanding in quiet, sentence understanding in noise, distortion product otoacoustic emissions (DPOAEs), middle-ear muscle reflexes (MEMRs), and auditory evoked potentials (AEPs), including auditory brainstem responses (ABRs), middle latency responses (MLRs), and late latency responses (LLRs). Each participant also received magnetic resonance imaging (MRI). Compared to the control group, we found that individuals with mTBI had reduced DPOAE amplitudes that revealed a compound effect of age, elevated MEMR thresholds for an ipsilateral broadband noise elicitor, longer ABR Wave I latencies for click and 4 kHz tone burst elicitors, longer ABR Wave III latencies for 4 kHz tone bursts, larger MLR Na and Nb amplitudes, smaller MLR Pb amplitudes, longer MLR Pa latencies, and smaller LLR N1 amplitudes for older individuals with mTBI. Further, mTBI individuals with combined hearing difficulty and noise sensitivity had a greater number of deficits on thalamic and cortical AEP measures compared to those with only one/no self-reported auditory symptoms. This finding was corroborated with MRI, which revealed significant structural differences in the auditory cortical areas of mTBI participants who reported combined hearing difficulty and noise sensitivity, including an enlargement of left transverse temporal gyrus (TTG) and bilateral planum polare (PP). These findings highlight the need for continued investigations toward identifying individualized audiologic assessments and treatments that are sensitive to mTBI pathophysiology.

A cross-sectional survey of non-specialist Australian audio-vestibular clinical practice for traumatic brain injury and rehabilitation

OBJECTIVE

This study explored non-specialist audiological clinical practice in the context of traumatic brain injury (TBI), and whether such practices incorporated considerations of TBI-related complexities pertaining to identification, diagnosis and management of associated auditory and vestibular disturbances.

DESIGN

A cross-sectional online survey exploring clinical practice, TBI-related training and information provision was distributed to audiologists across Australia via Audiology Australia and social media. Fifty audiologists, 80% female and 20% male, participated in this study. Years of professional practice ranged from new graduate to more than 20 years of experience.

RESULTS

Clear gaps of accuracy in knowledge and practice across all survey domains relating to the identification, diagnosis and management of patients with auditory and/or vestibular deficits following TBI were evident. Further, of the surveyed audiologists working in auditory and vestibular settings, 91% and 86%, respectively, reported not receiving professional development for the diagnosis and management of post-traumatic audio-vestibular deficits.

CONCLUSION

Inadequate resources, equipment availability and TBI-related training may have contributed to the gaps in service provision, influencing audiological management of patients with TBI. A tailored TBI approach to identification, diagnosis and management of post-traumatic auditory and vestibular disturbances is needed.

The Impact of Traumatic Brain Injury on Binaural Processing in Young and Middle-Age Adults

PURPOSE

This study examined the impact of traumatic brain injury (TBI) on self-perceived hearing and suprathreshold binaural processing in young and middle-age adults.

METHOD

Ninety-three adults with normal hearing (thresholds ≤ 25 dB HL, 250-4000 Hz) participated in one of four groups: 38 young adults, 23 young adults with TBI, 16 middle-age adults, and 16 middle-age adults with TBI. Self-perceived hearing difficulty was measured via questionnaires. Binaural processing was measured using dichotic word recognition, the Listening in Spatialized Noise-Sentences Test (LiSN-S), and the 500-Hz masking level difference (MLD). For each participant, a composite binaural processing (CBP) score was calculated to obtain a global metric of binaural processing performance. The CBP was composed of six measures from the three behavioral tests, including the S0N0 and SπN0 thresholds from the 500-Hz MLD, the low- and high-cue speech recognition thresholds from the LiSN-S, and the free and directed recall ear advantages from the dichotic word test.

RESULTS

The middle-age TBI group reported significantly greater degrees of self-perceived hearing difficulty than the other groups. On average, the middle-age TBI group performed poorer on the individual binaural processing tests; however, the differences were significant for the S0N0 and SπN0 MLD thresholds only. Results for the global metric of binaural processing revealed significantly poorer CBP scores for the middle-age TBI group compared to the other groups.

CONCLUSIONS

Results demonstrate that both age and a positive history of TBI contributed to deficits in suprathreshold binaural processing. Middle-age adults with a history of TBI are at risk for experiencing presenescent deficits in suprathreshold binaural processing deficits, despite having clinically normal hearing.

Sensory hypersensitivities are associated with post-traumatic headache-related disability

OBJECTIVE

To examine whether sensory hypersensitivity contributes to headache-related disability in a secondary analysis of patients with post-traumatic headache.

BACKGROUND

Up to one-third of individuals with traumatic brain injuries report persistent headache 3 months post-injury. High rates of allodynia and photophobia have been observed in clinical studies and animal models of post-traumatic headache, but we do not fully understand how sensory amplifications impact post-traumatic headache-related disability.

METHODS

We identified a cross-sectional sample of patients from the American Registry for Migraine Research database with new or worsening headaches post-head injury from 2016 to 2020 and performed a secondary analysis of those data. We modeled the relationship between sensory sensitivity and Migraine Disability Assessment scores using questionnaires. Candidate variables included data collection features (study site and year), headache-related and general clinical features (headache frequency, migraine diagnosis, abuse history, sex, age, cognitive and affective symptom scores), and sensory symptoms (related to light, sound, and touch sensitivity).

RESULTS

The final sample included 193 patients (median age 46, IQR 22; 161/193, 83.4% female). Migraine Disability Assessment scores ranged from 0 to 260 (median 47, IQR 87). The final model included allodynia, hyperacusis, photosensitivity, headache days per month, abuse history, anxiety and depression, cognitive dysfunction, and age (R2  = 0.43). An increase of one point in allodynia score corresponded to a 3% increase in headache disability (95% CI: 0%-7%; p = 0.027), an increase of one-tenth of a point in the photosensitivity score corresponded to a 12% increase (95% CI: 3%-25%; p = 0.002), and an increase of one point in the hyperacusis score corresponded to a 2% increase (95% CI: 0%-4%; p = 0.016).

CONCLUSIONS

Increased photosensitivity, allodynia, and hyperacusis were associated with increased headache-related disability in this sample of patients with post-traumatic headache. Symptoms of sensory amplification likely contribute to post-traumatic headache-related disability and merit an ongoing investigation into their potential as disease markers and treatment targets.

Sensory sensitivity after acquired brain injury: A systematic review

Patients with acquired brain injury frequently report experiencing sensory stimuli as abnormally under- (sensory hyposensitivity) or overwhelming (sensory hypersensitivity). Although they can negatively impact daily functioning, these symptoms are poorly understood. To provide an overview of the current evidence on atypical sensory sensitivity after acquired brain injury, we conducted a systematic literature review. The primary aim of the review was to investigate the behavioural and neural mechanisms that are associated with self-reported sensory sensitivity. Studies were included when they studied sensory sensitivity in acquired brain injury populations, and excluded when they were not written in English, consisted of non-empirical research, did not study human subjects, studied pain, related sensory sensitivity to peripheral injury or studied patients with a neurodegenerative disorder, meningitis, encephalitis or a brain tumour. The Web of Science, PubMed and Scopus databases were searched for appropriate studies. A qualitative synthesis of the results of the 81 studies that were included suggests that abnormal sensory thresholds and a reduced information processing speed are candidate behavioural mechanisms of atypical subjective sensory sensitivity after acquired brain injury. Furthermore, there was evidence for an association between subjective sensory sensitivity and structural grey or white matter abnormalities, and to functional abnormalities in sensory cortices. However, further research is needed to explore the causation of atypical sensory sensitivity. In addition, there is a need for the development of adequate diagnostic tools. This can significantly advance the quantity and quality of research on the prevalence, aetiology, prognosis and treatment of these symptoms.

Concussion Management Guidelines Neglect Auditory Symptoms

Tinnitus, noise sensitivity, and hearing difficulties are commonly reported secondary to head injury. These auditory deficits have been shown to negatively impact daily functioning, and yet, often go unnoticed by health care professionals. The purpose of this editorial is to explain why it is essential for clinical practice guidelines that address the management of patients who have experienced a head injury to incorporate assessment and rehabilitation of auditory symptoms.

[Auditory phenomena as differential diagnostics to tinnitus]

INTRODUCTION

In the auditory system, subjective tinnitus is known as phantom perception. Humans also report illusionary misperceptions of real listening impressions and complex scene-like acoustic fantasies without external hearing stimulus. The exact pathophysiological relationships of the auditory phenomena are still unclear. Important comorbidities include hearing loss, brain disease and mental disorders.

METHODS

In a literature search in the PubMed database, publications were evaluated until March 2021 on the search terms tinnitus, palinacousis, pareidolia, synesthesia, aura, acoustic hallucination with regard to similarities and differences to subjective tinnitus.

RESULTS

Subjective tinnitus can occur together with other auditory phenomena in an individual. Diagnostically important is the relationship between hearing loss and tinnitus as well as between tinnitus and hearing loss in the corresponding frequency range. With hearing loss, other auditory phenomena may occur.

CONCLUSION

The occurrence of various auditory phenomena simultaneously in a person suggests an auditory perceptual continuum with common physiological processing structures. People with hearing loss should be asked about the various auditory phenomena. For all auditory phenomena, audiometric examination should be part of the diagnostic standard.

From Provider to Advocate: The Complexities of Traumatic Brain Injury Prompt the Evolution of Provider Engagement

Treating a patient with traumatic brain injury requires an interdisciplinary approach because of the pervasive, profound and protean manifestations of this condition. In this review, key aspects of the medical history and review of systems will be described in order to highlight how the role of any provider must evolve to become a better patient advocate. Although this review is written from the vantage point of a vision care provider, it is hoped that patients, caregivers and providers will recognize the need for a team approach.

Baseline, retest, and post-injury profiles of auditory neural function in collegiate football players

OBJECTIVES

Recent retrospective studies report differences in auditory neurophysiology between concussed athletes and uninjured controls using the frequency-following response (FFR). Adopting a prospective design in college football players, we compared FFRs before and after a concussion and evaluated test-retest reliability in non-concussed teammates.

DESIGN

Testing took place in a locker room. We analysed the FFR to the fundamental frequency (F0) (FFR-F0) of a speech stimulus, previously identified as a potential concussion biomarker. Baseline FFRs were obtained during the football pre-season. In athletes diagnosed with concussions during the season, FFRs were measured days after injury and compared to pre-season baseline. In uninjured controls, comparisons were made between pre- and post-season.

STUDY SAMPLE

Participants were Tulane University football athletes (n = 65).

RESULTS

In concussed athletes, there was a significant group-level decrease in FFR-F0 from baseline (26% decrease on average). By contrast, the control group's change from baseline was not statistically significant, and comparisons of pre- and post-season had good repeatability (intraclass correlation coefficient = 0.75).

CONCLUSIONS

Results converge with previous work to evince suppressed neural function to the FFR-F0 following concussion. This preliminary study paves the way for larger-scale clinical evaluation of the specificity and reliability of the FFR as a concussion diagnostic.HighlightsThis prospective study reveals suppressed neural responses to sound in concussed athletes compared to baseline.Neural responses to sound show good repeatability in uninjured athletes tested in a locker-room setting.Results support the feasibility of recording frequency-following responses in non-laboratory conditions.

Papesh M, Gallun FJ. A Questionnaire Survey of Current Rehabilitation Practices for Adults With Normal Hearing Sensitivity Who Experience Auditory Difficulties

Purpose A questionnaire survey was conducted to collect information from clinical audiologists about rehabilitation options for adult patients who report significant auditory difficulties despite having normal or near-normal hearing sensitivity. This work aimed to provide more information about what audiologists are currently doing in the clinic to manage auditory difficulties in this patient population and their views on the efficacy of recommended rehabilitation methods. Method A questionnaire survey containing multiple-choice and open-ended questions was developed and disseminated online. Invitations to participate were delivered via e-mail listservs and through business cards provided at annual audiology conferences. All responses were anonymous at the time of data collection. Results Responses were collected from 209 participants. The majority of participants reported seeing at least one normal-hearing patient per month who reported significant communication difficulties. However, few respondents indicated that their location had specific protocols for the treatment of these patients. Counseling was reported as the most frequent rehabilitation method, but results revealed that audiologists across various work settings are also successfully starting to fit patients with mild-gain hearing aids. Responses indicated that patient compliance with computer-based auditory training methods was regarded as low, with patients generally preferring device-based rehabilitation options. Conclusions Results from this questionnaire survey strongly suggest that audiologists frequently see normal-hearing patients who report auditory difficulties, but that few clinicians are equipped with established protocols for diagnosis and management. While many feel that mild-gain hearing aids provide considerable benefit for these patients, very little research has been conducted to date to support the use of hearing aids or other rehabilitation options for this unique patient population. This study reveals the critical need for additional research to establish evidence-based practice guidelines that will empower clinicians to provide a high level of clinical care and effective rehabilitation strategies to these patients.

Auditory Quality-of-Life Measures in Patients With Traumatic Brain Injury and Normal Pure Tone Audiometry

Auditory complaints are commonly reported following traumatic brain injury (TBI). However, few studies have examined patient-reported auditory symptomatology and quality-of-life metrics in individuals with TBI. We hypothesize that following TBI, individuals can experience auditory symptoms even with hearing thresholds in the normal range. Adult patients with normal auditory thresholds and a history of TBI were evaluated for subjective hearing loss, tinnitus, aural fullness, hyperacusis, and autophony. Hearing Handicap Inventory for Adults, Tinnitus Handicap Inventory, and Hyperacusis Questionnaire were administered. Thirty-one patients were prospectively recruited. Twenty-eight TBI participants (90%) reported ≥1 auditory symptoms at the time of survey intake. Mild to severe handicap in the Hearing Handicap Inventory for Adults and Tinnitus Handicap Inventory was reported in 71.4% and 40% of the participants with hearing loss and tinnitus, respectively. Hyperacusis handicap was considered significant in 41.1% of the participants who complained of hyperacusis and completed the survey. Despite normal hearing thresholds, individuals with TBI experience decrements in auditory quality-of-life metrics. Level of evidence: 3.

Clinical correlates of insomnia in patients with persistent post-traumatic headache compared with migraine

BACKGROUND

Close associations between insomnia with other clinical factors have been identified in migraine, but there have been few studies investigating associations between insomnia and clinical factors in patients with persistent post-traumatic headache (PPTH). The study objective was to contrast the severity of insomnia symptoms in PPTH, migraine, and healthy controls, and to identify factors associated with insomnia in patients with PPTH vs. migraine.

METHODS

In this cross-sectional cohort study, 57 individuals with PPTH attributed to mild traumatic brain injury, 39 with migraine, and 39 healthy controls were included. Participants completed a detailed headache characteristics questionnaire, the Migraine Disability Assessment Scale (MIDAS), Insomnia Severity Index (ISI), Hyperacusis Questionnaire (HQ), Allodynia Symptom Checklist, Photosensitivity Assessment Questionnaire, Beck Depression Inventory (BDI), State-Trait Anxiety Inventory, Post-Traumatic Stress Disorder (PTSD) checklist, Ray Auditory Verbal Learning Test, and the Trail Making Test A and B to assess headache characteristics, disability, insomnia symptoms, sensory hypersensitivities, and neuropsychological factors. Fisher's test and one-way ANOVA or Tukey's Honest Significant Difference were used to assess group differences of categorical and continuous data. Stepwise linear regression analyses were conducted to identify clinical variables associated with insomnia symptoms.

RESULTS

Those with PPTH had significantly higher ISI scores (16.7 ± 6.6) compared to migraine patients (11.3 ± 6.4) and healthy controls (4.1 ± 4.8) (p <  0.001). For those with PPTH, insomnia severity was most strongly correlated with the BDI (Spearman's rho (ρ) = 0.634, p <  0.01), followed by Trait Anxiety (ρ = 0.522, p <  0.01), PTSD (ρ = 0.505, p <  0.01), HQ (ρ = 0.469, p <  0.01), State Anxiety (ρ = 0.437, p <  0.01), and MIDAS scores (ρ = 0.364, p <  0.01). According to linear regression models, BDI, headache intensity, and hyperacusis scores were significantly positively associated with insomnia severity in those with PPTH, while only delayed memory recall was negatively associated with insomnia severity in those with migraine.

CONCLUSIONS

Insomnia symptoms were more severe in those with PPTH compared to migraine and healthy control cohorts. Depression, headache intensity, and hyperacusis were associated with insomnia in individuals with PPTH. Future studies should determine the bidirectional impact of treating insomnia and its associated symptoms.