[Audiologic rehabilitation of patients with cochlear implants]

Language profile of children with cochlear implants: comparative study about the effect of age of cochlear implantation and the duration of rehabilitation

PURPOSE

The analysis of different language domains and exploration of variables that affect the outcomes of cochlear implantation would help to document the efficacy of cochlear implantation and intervention programs. The aim of this work was to examine the language profile of children with Cochlear Implants (CI) and to assess the effect of age at the time of cochlear implantation and the impact of duration of rehabilitation on the development of linguistic abilities for cochlear implanted children.

METHODS

The study was conducted on 46 Arabic speaking children using unilateral CI who are receiving regular post-cochlear auditory and language rehabilitation in the phoniatrics unit, Kasr Alaini hospital. A Proficient Preschooler Language Evaluation (APPEL TOOL) was applied for the assessment of different language domains.

RESULTS

Children who received post implant rehabilitation for ≥ 2 years showed significant improvement in all subtests' scores of APPEL tool than children who received same rehabilitation for ≤ 1 year. There was no significant difference of language scores between children who have received CI before age of 3 years and those who have been implanted after age of 3 years.

CONCLUSION

This study showed that the language profile of CI children was beneficially affected by the longer duration of therapy post implantation.

[Vestibular Schwannoma: Factors in Therapy Decision-Making]

The treatment of vestibular schwannomas (VS) has always posed a challenge for physicians. Three essential treatment principles are available: wait-and-scan, surgery, and stereotactic radiotherapy. In addition to the type of treatment, decisions must be made regarding the optimal timing of therapy, the combination of different treatment modalities, the potential surgical approach, and the type and intensity of radiation. Factors influencing the therapy decision include tumor location and size or stage, patient age, comorbidities, symptoms, postoperative hearing rehabilitation options, patient preferences, and, not least, the experience of the surgeons and the personnel and technical capabilities of the clinical site. This article begins with a brief overview of vestibular schwannomas, then outlines the fundamental interdisciplinary treatment options, and finally discusses the ENT (ear, nose, and throat)-relevant factors in the therapy decision.

Speech comprehension in noise-considerations for ecologically valid assessment of communication skills ability with cochlear implants

BACKGROUND

Nowadays, cochlear implant (CI) patients mostly show good to very good speech comprehension in quiet, but there are known problems with communication in everyday noisy situations. There is thus a need for ecologically valid measurements of speech comprehension in real-life listening situations for hearing-impaired patients. The additional methodological effort must be balanced with clinical human and spatial resources. This study investigates possible simplifications of a complex measurement setup.

METHODS

The study included 20 adults from long-term follow-up after CI fitting with postlingual onset of hearing impairment. The complexity of the investigated listening situations was influenced by changing the spatiality of the noise sources and the temporal characteristics of the noise. To compare different measurement setups, speech reception thresholds (SRT) were measured unilaterally with different CI processors and settings. Ten normal-hearing subjects served as reference.

RESULTS

In a complex listening situation with four loudspeakers, differences in SRT from CI subjects to the control group of up to 8 dB were found. For CI subjects, this SRT correlated with the situation with frontal speech signal and fluctuating interference signal from the side with R2 = 0.69. For conditions with stationary interfering signals, R2 values <0.2 were found.

CONCLUSION

There is no universal solution for all audiometric questions with respect to the spatiality and temporal characteristics of noise sources. In the investigated context, simplification of the complex spatial audiometric setting while using fluctuating competing signals was possible.

Extended Preoperative Audiometry for Outcome Prediction and Risk Analysis in Patients Receiving Cochlear Implants

BACKGROUND

The outcome of cochlear implantation has improved over the last decades, but there are still patients with less benefit. Despite numerous studies examining the cochlear implant (CI) outcome, variations in speech comprehension with CI remains incompletely explained. The aim of this study was therefore to examine preoperative pure-tone audiogram and speech comprehension as well as aetiology, to investigate their relationship with postoperative speech comprehension in CI recipients.

METHODS

A retrospective study with 664 ears of 530 adult patients was conducted. Correlations between the target variable postoperative word comprehension with the preoperative speech and sound comprehension as well as aetiology were investigated. Significant correlations were inserted into multivariate models. Speech comprehension measured as word recognition score at 70 dB with CI was analyzed as (i) a continuous and (ii) a dichotomous variable.

RESULTS

All variables that tested preoperative hearing were significantly correlated with the dichotomous target; with the continuous target, all except word comprehension at 65 dB with hearing aid. The strongest correlation with postoperative speech comprehension was seen for monosyllabic words with hearing aid at 80 dB. The preoperative maximum word comprehension was reached or surpassed by 97.3% of CI patients. Meningitis and congenital diseases were strongly negatively associated with postoperative word comprehension. The multivariate model was able to explain 40% of postoperative variability.

CONCLUSION

Speech comprehension with hearing aid at 80 dB can be used as a supplementary preoperative indicator of CI-aided speech comprehension and should be measured regularly in the clinical routine. Combining audiological and aetiological variables provides more insights into the variability of the CI outcome, allowing for better patient counselling.

[Speech comprehension in noise-considerations for ecologically valid assessment of communication skills ability with cochlear implants. German version]

BACKGROUND

Nowadays, cochlear implant (CI) patients mostly show good to very good speech comprehension in quiet, but there are known problems with communication in everyday noisy situations. There is thus a need for ecologically valid measurements of speech comprehension in real-life listening situations for hearing-impaired patients. The additional methodological effort must be balanced with clinical human and spatial resources. This study investigates possible simplifications of a complex measurement setup.

METHODS

The study included 20 adults from long-term follow-up after CI fitting with postlingual onset of hearing impairment. The complexity of the investigated listening situations was influenced by changing the spatiality of the noise sources and the temporal characteristics of the noise. To compare different measurement setups, speech reception thresholds (SRT) were measured unilaterally with different CI processors and settings. Ten normal-hearing subjects served as reference.

RESULTS

In a complex listening situation with four loudspeakers, differences in SRT from CI subjects to the control group of up to 8 dB were found. For CI subjects, this SRT correlated with the situation with frontal speech signal and fluctuating interference signal from the side with R2 = 0.69. For conditions with stationary interfering signals, R2 values <0.2 were found.

CONCLUSION

There is no universal solution for all audiometric questions with respect to the spatiality and temporal characteristics of noise sources. In the investigated context, simplification of the complex spatial audiometric setting while using fluctuating competing signals was possible.

Algorithm-Based Hearing and Speech Therapy Rehabilitation after Cochlear Implantation

INTRODUCTION

Due to the changes in the indication range for cochlear implants and the demographic development towards an aging society, more and more people are in receipt of cochlear implants. An implantation requires a close-meshed audiological and logopedic aftercare. Hearing therapy rehabilitation currently requires great personnel effort and is time consuming. Hearing and speech therapy rehabilitation can be supported by digital hearing training programs. However, the apps currently on the market are to a limited degree personalized and structured. Increasing digitalization makes it possible, especially in times of pandemics, to decouple hearing therapy treatment from everyday clinical practice.

MATERIAL AND METHODS

For this purpose, an app is in development that provides hearing therapy tailored to the patient. The individual factors that influence hearing outcome are considered. Using intelligent algorithms, the app determines the selection of exercises, the level of difficulty and the speed at which the difficulty is increased.

RESULTS

The app works autonomously without being connected to local speech therapists. In addition, the app is able to analyze patient difficulties within the exercises and provides conclusions about the need for technical adjustments.

CONCLUSIONS

The presented newly developed app represents a possibility to support, replace, expand and improve the classic outpatient hearing and speech therapy after CI implantation. The way the application works allows it to reach more people and provide a time- and cost-saving alternative to traditional therapy.

Speech comprehension across multiple CI processor generations: Scene dependent signal processing

OBJECTIVES

In clinical practice, characterization of speech comprehension for cochlear implant (CI) patients is typically administered by a set of suprathreshold measurements in quiet and in noise. This study investigates speech comprehension of the three most recent cochlear implant sound processors; CP810, CP910, and CP1000 (Cochlear Limited). To compare sound processor performance across generations and input dynamic range changes, the state-of-the art signal processing technologies available in each sound processor were enabled. Outcomes will be assessed across a range of stimulation intensities, and finally analyzed with respect to normal hearing listeners.

METHODS

In a prospective study, 20 experienced postlingually deafened CI patients who received a Nucleus CI in the ENT department of the University Hospital of SH in Kiel were recruited. Speech comprehension was measured in quiet at 40, 50, and 65 dBSPL with monosyllabic words as well as by speech reception threshold for two-digit numbers. In noise, speech reception thresholds were measured with the adaptive German matrix test with speech and noise in front.

RESULTS

We found that high levels of open-set speech comprehension are achieved at suprathreshold presentation levels in quiet. However, results at lower test levels have remained mostly unchanged for tested sound processors with default dynamic range. Expanding the lower limit of the acoustic input dynamic range yields better speech comprehension at lower presentation levels. In noise the application of ForwardFocus improves the speech reception. Overall, a continuous improvement for speech perception across three generations of CI sound processors was found.

CONCLUSIONS

Findings motivate further development of signal pre-processing, an additional focus of clinical work on lower stimulation levels, and automation of ForwardFocus.

LEVEL OF EVIDENCE

2.

[New ways in hearing rehabilitation after cochlear implantation]

INTRODUCTION

After cochlear implantation, auditory and speech training is usually necessary. Up until now, this has been performed on an out- or inpatient basis in direct contact with a therapist. Due to technical advances but also particularly because of an increasing use of digital media and a desire for mobility and independence, the demand for digital training programs is increasing in the field of hearing rehabilitation.

MATERIALS AND METHODS

In a first step, the most important elements of auditory training were determined on the basis of commonly used auditory and speech processing models, and the core features of a computer-based teletherapeutic hearing platform were defined. This process considered motivational elements and adaptive mechanisms as regularly used in educational and speech and language therapy. In a second step, an initial prototype of the "train2hear" teletherapeutic hearing platform was developed by an interdisciplinary research team.

RESULTS

The core of the train2hear platform is an initial analysis according to the International Classification of Functioning, Disability, and Health (ICF), on the basis of which an individual training plan is designed. Various adaptive mechanisms enable the level of difficulty to be continually adapted to the individual user's learning progress. A videoconference tool enables contact between the patient and the therapist.

CONCLUSION

The train2hear platform represents a first prototype of a computer-based auditory rehabilitation program in German. Further evaluation and development in a clinical study are needed to determine the feasibility and efficacy of the platform.

[Auditory group therapy in adult cochlear implant rehabilitation]

BACKGROUND

Auditory training is an established intervention in adult cochlear implant (CI) aural rehabilitation. In most cases, training is implemented in an individual therapy setting. Increasing patient numbers and the associated time-economic and cost-related demands as well as psychosocial and communicative aspects support the use of aural group interventions.

OBJECTIVES

This study aimed 1) to describe concepts and contents of group interventions for adult CI users and 2) to present results of a questionnaire-based evaluation.

METHODS

Group interventions have been offered at the CI Centre Erlangen CICERO for several years. In Auditory Training Groups, exercises have priority, while Thematic Group Workshops focus on psychosocial aspects and provide information for the participants. The Auditory Training Groups were evaluated based on a patient questionnaire. Additionally, the reliability of the questionnaire was analyzed.

RESULTS

The median overall satisfaction of CI users participating in Auditory Training Groups was rated as good. Training of speech perception in noise as well as communicative exchange are of great importance for CI users. They rated the therapeutic design as very good to good. Reliability analysis showed significant positive intercorrelations of the questionnaire items.

CONCLUSION

Group interventions are well accepted by CI users and represent a useful complement to individual therapy during the rehabilitation process. As group interventions place special demands on patients and therapists, structured and well-proven concepts should be used in practice.

The Role of Auditory Evoked Potentials in the Context of Cochlear Implant Provision

: Auditory evoked potentials (AEP) are highly demanded during the whole process of equipping patients with cochlear implants (CI). They play an essential role in preoperative diagnostics, intraoperative testing, and postoperative monitoring of auditory performance and success. The versatility of AEP's is essentially enhanced by their property to be evokable by acoustic as well as electric stimuli. Thus, the electric responses of the auditory system following acoustic stimulation and recorded by the conventional surface technique as well as by transtympanic derivation from the promontory (Electrocochleography [ECochG]) are used for the quantitative determination of hearing loss and, additionally, electrically evoked compound actions potentials (ECAP) can be recorded with the intracochlear electrodes of the implant just adjacent to the stimulation electrode to check the functional integrity of the device and its coupling to the auditory system. The profile of ECAP thresholds is used as basis for speech processor fitting, the spread of excitation (SOE) allows the identification of electrode mislocations such as array foldover, and recovery functions may serve to optimize stimulus pulse rate. These techniques as well as those relying on scalp surface activity originating in the brainstem or the auditory cortex accompany the CI recipient during its whole life span and they offer valuable insights into functioning and possible adverse effects of the CI for clinical and scientific purposes.

Current audiological diagnostics

Today's audiological functional diagnostics is based on a variety of hearing tests, whose large number takes account of the variety of malfunctions of a complex sensory organ system and the necessity to examine it in a differentiated manner and at any age of life. The objective is to identify nature and origin of the hearing loss and to quantify its extent as far as necessary to dispose of the information needed to initiate the adequate medical (conservative or operational) treatment or the provision with technical hearing aids or prostheses. Moreover, audiometry provides the basis for the assessment of impairment and handicap as well as for the calculation of the degree of disability. In the present overview, the current state of the method inventory available for practical use is described, starting from basic diagnostics over to complex special techniques. The presentation is systematically grouped in subjective procedures, based on psychoacoustic exploration, and objective methods, based on physical measurements: preliminary hearing tests, pure tone threshold, suprathreshold processing of sound intensity, directional hearing, speech understanding in quiet and in noise, dichotic hearing, tympanogram, acoustic reflex, otoacoustic emissions and auditory evoked potentials. Apart from a few still existing gaps, this method inventory covers the whole spectrum of all clinically relevant functional deficits of the auditory system.

[Phoneme discrimination training with experienced cochlear implant listeners]

BACKGROUND

Computer-based auditory training programmes seem to be a useful tool in the process of auditory rehabilitation after cochlear implantation (CI). Currently, little is known about the learning mechanism and efficiency of such programs. The aim of the study was to evaluate a specific auditory training programme for phoneme discrimination in experienced CI listeners.

MATERIALS AND METHODS

A total of 15 CI adult listeners with more than 2 years' CI experience participated in the auditory training. Over a period of 3 weeks they were instructed to train their phoneme discrimination via computer twice a week. Training material consisted of special syllables for consonants (vCv) and vowels (cVc) discrimination.

RESULTS

The discrimination abilities for consonants and vowels improved significantly over the training period for training group participants, whereas the changes for the consonants were higher. In addition, the improvement for voiced and unvoiced consonants was significant.

CONCLUSION

Computerised auditory training with phonemes improves CI listeners' discrimination abilities for consonants and vowels.

[The Freiburg speech intelligibility test : A pillar of speech audiometry in German-speaking countries]

The Freiburg speech intelligibility test according to DIN 45621 was introduced around 60 years ago. For decades, and still today, the Freiburg test has been a standard whose relevance extends far beyond pure audiometry. It is used primarily to determine the speech perception threshold (based on two-digit numbers) and the ability to discriminate speech at suprathreshold presentation levels (based on monosyllabic nouns). Moreover, it is a measure of the degree of disability, the requirement for and success of technical hearing aids (auxiliaries directives), and the compensation for disability and handicap (Königstein recommendation). In differential audiological diagnostics, the Freiburg test contributes to the distinction between low- and high-frequency hearing loss, as well as to identification of conductive, sensory, neural, and central disorders. Currently, the phonemic and perceptual balance of the monosyllabic test lists is subject to critical discussions. Obvious deficiencies exist for testing speech recognition in noise. In this respect, alternatives such as sentence or rhyme tests in closed-answer inventories are discussed.

[Speech intelligibility tests in cochlear implant patients]

The investigation of speech intelligibility under quiet and noisy conditions is essential to evaluate the auditory and verbal rehabilitation of cochlear implant patients. A set of audiological tests is introduced that has been validated and optimized by empirical investigations in adult cochlear implant users. The Kiel logatom test, the Freiburg speech intelligibility test and the adaptive measurement of speech perception threshold in noise with the Oldenburg sentence test are methods suggested for clinical use, which are also applicable for scientific investigations. The test battery provides results that can be interpreted by every professional involved in the rehabilitation process of cochlear implant patients.