Permanent Hearing Impairment Research Articles

Impact of very high-frequency sound and low-frequency ultrasound on people - the current state of the art.

For several decades, low-frequency ultrasound (<100 kHz) has been widely used in industry, medicine, commerce, military service and the home. The objective of the study was to present the current state of the art on the harmful effects of low-frequency airborne ultrasound on people, especially in occupational settings. The scientific literature search was performed using accessible medical and other databases (WOS, BCI, CCC, DRCI, DIIDW, KJD, MEDLINE, RSCI, SCIELO and ZOOREC), and the obtained results were then hand-searched to eliminate non-relevant papers. This review includes papers published in 1948-2018. The potential effects of the low-frequency airborne ultrasound have been classified as auditory and non-auditory effects, including subjective, physiological, and thermal effects. In particular, already in the 1960-1970s, it was demonstrated that ultrasonic exposure, when sufficiently intense, appeared to result in a syndrome involving nausea, headache, vomiting, disturbance of coordination, dizziness, and fatigue, and might cause a temporary or permanent hearing impairment. However, since that time, not too much work has been done. Further studies are needed before any firm conclusions can be drawn about the auditory and non-auditory effects of low-frequency airborne ultrasound. Int J Occup Med Environ Health. 2020;33(4):389-408.

Vascular endothelial growth factor is required for regeneration of auditory hair cells in the avian inner ear

Hair cells in the auditory organ of the vertebrate inner ear are the sensory receptors that convert acoustic stimuli into electrical signals that are conveyed along the auditory nerve to the brainstem. Hair cells are highly susceptible to ototoxic drugs, infection, and acoustic trauma, which can cause cellular degeneration. In mammals, hair cells that are lost after damage are not replaced, leading to permanent hearing impairments. By contrast, supporting cells in birds and other non-mammalian vertebrates regenerate hair cells after damage, which restores hearing function. The cellular mechanisms that regulate hair cell regeneration are not well understood. We investigated the role of vascular endothelial growth factor (VEGF) during regeneration of auditory hair cells in chickens after ototoxic injury. Using RNA-Seq, immunolabeling, and in situ hybridization, we found that VEGFA, VEGFC, VEGFR1, VEGFR2, and VEGFR3 were expressed in the auditory epithelium, with VEGFA expressed in hair cells and VEGFR1 and VEGFR2 expressed in supporting cells. Using organotypic cultures of the chicken cochlear duct, we found that blocking VEGF receptor activity during hair cell injury reduced supporting cell proliferation as well as the numbers of regenerated hair cells. By contrast, addition of recombinant human VEGFA to organ cultures caused an increase in both supporting cell division and hair cell regeneration. VEGF’s effects on supporting cells were preserved in isolated supporting cell cultures, indicating that VEGF can act directly upon supporting cells. These observations demonstrate a heretofore uncharacterized function for VEGF signaling as a critical positive regulator of hair cell regeneration in the avian inner ear.

The use of nonhuman primates in studies of noise injury and treatment.

Exposure to prolonged or high intensity noise increases the risk for permanent hearing impairment. Over several decades, researchers characterized the nature of harmful noise exposures and worked to establish guidelines for effective protection. Recent laboratory studies, primarily conducted in rodent models, indicate that the auditory system may be more vulnerable to noise-induced hearing loss (NIHL) than previously thought, driving renewed inquiries into the harmful effects of noise in humans. To bridge the translational gaps between rodents and humans, nonhuman primates (NHPs) may serve as key animal models. The phylogenetic proximity of NHPs to humans underlies tremendous similarity in many features of the auditory system (genomic, anatomical, physiological, behavioral), all of which are important considerations in the assessment and treatment of NIHL. This review summarizes the literature pertaining to NHPs as models of hearing and noise-induced hearing loss, discusses factors relevant to the translation of diagnostics and therapeutics from animals to humans, and concludes with some of the practical considerations involved in conducting NHP research.

Listening To Music While Exercising Increases The Risk For Noise-Induced Hearing Loss

Music has an ergogenic effect on exercise performance, improves motivation, decreases exertion, and delays the onset of fatigue. However, loud sound levels from music can cause permanent damage to the inner ear resulting in noise-induced hearing loss (NIHL). PURPOSE: The purpose of this study was to assess the risk of NIHL among students utilizing campus recreational facilities and examine whether music used as a motivator was associated with increased risk for NIHL. METHODS: One hundred and nineteen students were recruited from the main fitness center on college campus. Physical activity level was recalled using a modified short version of the International Physical Activity Questionnaire. Music intensity levels were assessed by a sound pressure level mannequin with a built-in microphone. Thirty second samples were taken in 5 second intervals using participant’s personal listening devices. Average, minimum, and maximum sound levels were recorded in decibels (dBA). The estimated risk for NIHL was established based on the average sound level and duration of exposure using NIOSH criteria. Participants indicated whether music was a motivator during a workout. Descriptive statistics were performed for all variables. Chi-square analyses evaluated relations between risk for NIHL, gender, and music as a motivator. T-tests assessed the difference in average loudness level and gender. RESULTS: Participants were college students (51.3% males, 48.7% females). Majority of participants (89.1%) used music as motivation while exercising (93.4% male and 84.5% female, p>0.05). Twenty four percent of participants were at risk for NIHL, approaching statistical significance for gender (29.5% males vs 19% females, p=0.056). The average sound levels for the participants were 88.8+10.3 dBA and statistically significant for gender (90.9+10.6 dBA for males, 86.5+9.4 dBA for females, p=0.017). CONCLUSIONS: Every fourth college student listening to music while exercising was at risk for NIHL. NIHL is an avoidable cause of permanent hearing impairment. Recommendations for safe use of personal listening devices during workouts include keeping volume at a safe level, below 85 dBA, and limiting time spent using the device during workouts.

Mobilization of the Anterior/Posterior Inferior Cerebellar Artery on the Cerebellar Surface in Microvascular Decompression Surgery for Hemifacial Spasm: Potential Effect on Hearing Preservation.

The infrafloccular approach in microvascular decompression (MVD) for hemifacial spasm (HFS) reduces the risk of postoperative hearing impairment. However, location of the anterior/posterior inferior cerebellar artery (AICA/PICA) on the cerebellar surface in the surgical route requires mobilization to maintain the approach direction for the protection of hearing function. To evaluate the effectiveness of mobilization of the AICA/PICA on the cerebellar surface in the surgical route. Retrospective review of 101 patients dividing their cases into 2 groups, the mobilized group and nonmobilized group. Surgical results, brainstem auditory evoked potentials (BAEPs), age, and duration of microsurgery were compared. In the mobilized group, whether the artery was responsible for the HFS or not, and whether the artery branched perforators to the cerebellar surface or choroid plexus or not, were analyzed. No permanent hearing impairment occurred in any patient. The AICA/PICA was mobilized in 26 patients. No significant difference was found in surgical results, BAEP findings, and duration of microsurgery between the 2 groups, but age was younger in the mobilized group (P<.01). The mobilized artery was responsible in 14 cases and branched perforators in 7 cases in the mobilized group. The perforators did not obstruct mobilization. Mobilization of the AICA/PICA from the cerebellar surface is a useful technique to maintain the infrafloccular approach in MVD for HFS. This technique reduces the risk of postoperative hearing impairment.

A Model of Public Announcement System’s Dynamics Control in Smart City Environments

Nowadays, each individual is exposed to noise on a daily basis. Long exposure to noise pollution can be manifested through several health concerns such as bad mood, fatigue, insomnia, headache and loss of concentration, which can then cause reduced work ability and finally permanent hearing impairment. When considering urban areas, the most common type of noise source is traffic. Public announcement system are a vital and much needed part of every urban area and thus it should be constructed in a way that it delivers relevant information in a clear and understandable way while not disturbing the residents. Therefore, this paper proposes a model of public announcement system in urban places which aims to reduce unexpected and sudden loudness changes. The system is envisaged for public places, such as open bus stations surrounded with residential and commercial buildings. Several studies have shown that the residents of these buildings find sudden announcements very annoying and disturbing. The goal of this research is to reduce the sound level while retaining the principal loudness level. The study has shown that with the appropriate signal processing which includes a compressor and a limiter, these types of announcements can be made less annoying and disturbing for urban residents.

Findings from aetiological investigation of Auditory Neuropathy Spectrum Disorder in children referred to cochlear implant programs

ObjectivesAuditory neuropathy spectrum disorder (ANSD) is an audiological diagnosis characterised by hearing dysfunction in the presence of intact outer hair cell function in the cochlea. ANSD is thought to account for 7–10% of all childhood permanent hearing impairment, and can result from a range of pathological processes. This paper describes the rationale, methods and findings from the aetiological investigation of ANSD. MethodsRetrospective audit of four cochlear implant programmes. Results97 patients were identified. 79% of patients were identified before the age of one. Prematurity and jaundice were the most frequently identified aetiological factors. 33 patients had cochlear nerve deficiency on imaging. Genetic diagnoses identified included otoferlin, SX010 gene, connexin 26 and A1FM1 gene mutations. ANSD was seen in conjunction with syndromes including Kallman syndrome, CHARGE syndrome, X-linked deafness, SOTOS syndrome, Brown Vieletto Van Laere syndrome, and CAPOS syndrome. DiscussionWe present a two-level system of aetiological investigation that is clinically practical. Patients with ANSD sufficiently severe to consider cochlear implantation are generally identified at an early age. Aetiological investigation is important to guide prognosis and identify comorbidity. ConclusionPrematurity and jaundice are the most commonly identified aetiological factors in ANSD. Imaging findings identify crucial factors in a significant minority. An important minority may have genetic and syndromic diagnoses that require further management.

Association of Idiopathic Sudden Sensorineural Hearing Loss With Affective Disorders

Patients with idiopathic sudden sensorineural hearing loss (ISSNHL) often experience permanent hearing impairment, which could result in psychological perturbations. However, the relationship between ISSNHL and affective disorders, including depression, anxiety, and bipolar disorder, has not been fully evaluated. To investigate the potential relationship between ISSNHL and affective disorders using nationwide representative cohort sample data. This study used a nationwide propensity score-matched cohort sample from the Korean National Health Insurance Service database from 2002 through 2013, which comprises data from approximately 1 million patients. The study included 1425 patients with ISSNHL and 7125 individuals without ISSNHL who were matched using propensity score matching, according to sociodemographic factors and enrollment year. Survival analysis, the log-rank test, and Cox proportional hazards regression models were used to calculate the incidence, survival rate, and hazard ratio (HR) of developing affective disorders (anxiety, depression, and bipolar disorder) for each group. Of the total study population of 8550 (51.5% female), 961 developed affective disorders during the 11-year follow-up: 225 in the ISSNHL group (15.8%) and 736 in the comparison group (10.3%). We examined a total of 96 885.5 person-years (81 177.4 person-years in the comparison group and 15 708.1 person-years in the ISSNHL group). The incidence of affective disorders was 14.3 per 1000 person-years in the ISSNHL group and 9.1 per 1000 person-years in the comparison group. After adjustment for other factors, individuals with ISSNHL developed affective disorders more frequently than those in the comparison group (HR, 1.50; 95% CI, 1.30-1.75). Among the affective disorders, the HR of developing depression (HR, 1.66; 95% CI, 1.44-1.91) and anxiety disorder (HR, 1.79; 95% CI, 1.56-2.05) but not bipolar disorder (HR, 0.95; 95% CI, 0.54-1.70), was significantly greater in patients with ISSNHL. This cohort study suggests that ISSNHL is associated with an increased incidence of affective disorders, specifically depression and anxiety. Therefore, these findings suggest that clinicians should monitor patients with ISSNHL carefully, and take specific precautions to reduce their risk of depression and anxiety disorder.

Direct Reprogramming of Spiral Ganglion Non-neuronal Cells into Neurons: Toward Ameliorating Sensorineural Hearing Loss by Gene Therapy.

Primary auditory neurons (PANs) play a critical role in hearing by transmitting sound information from the inner ear to the brain. Their progressive degeneration is associated with excessive noise, disease and aging. The loss of PANs leads to permanent hearing impairment since they are incapable of regenerating. Spiral ganglion non-neuronal cells (SGNNCs), comprised mainly of glia, are resident within the modiolus and continue to survive after PAN loss. These attributes make SGNNCs an excellent target for replacing damaged PANs through cellular reprogramming. We used the neurogenic pioneer transcription factor Ascl1 and the auditory neuron differentiation factor NeuroD1 to reprogram SGNNCs into induced neurons (iNs). The overexpression of both Ascl1 and NeuroD1 in vitro generated iNs at high efficiency. Transcriptome analyses revealed that iNs displayed a transcriptome profile resembling that of endogenous PANs, including expression of several key markers of neuronal identity: Tubb3, Map2, Prph, Snap25, and Prox1. Pathway analyses indicated that essential pathways in neuronal growth and maturation were activated in cells upon neuronal induction. Furthermore, iNs extended projections toward cochlear hair cells and cochlear nucleus neurons when cultured with each respective tissue. Taken together, our study demonstrates that PAN-like neurons can be generated from endogenous SGNNCs. This work suggests that gene therapy can be a viable strategy to treat sensorineural hearing loss caused by degeneration of PANs.

Localized disorganization of the cochlear inner hair cell synaptic region after noise exposure.

ABSTRACTThe prevalence and importance of hearing damage caused by noise levels not previously thought to cause permanent hearing impairment has become apparent in recent years. The damage to, and loss of, afferent terminals of auditory nerve fibres at the cochlear inner hair cell has been well established, but the effects of noise exposure and terminal loss on the inner hair cell are less known. Using three-dimensional structural studies in mice we have examined the consequences of afferent terminal damage on inner hair cell morphology and intracellular structure. We identified a structural phenotype in the pre-synaptic regions of these damaged hair cells that persists for four weeks after noise exposure, and demonstrates a specific dysregulation of the synaptic vesicle recycling pathway. We show evidence of a failure in regeneration of vesicles from small membrane cisterns in damaged terminals, resulting from a failure of separation of small vesicle buds from the larger cisternal membranes.

Epidemiology of hearing loss in children of the first year of life

The aim of this study was the investigation of the epidemiology of permanent hearing impairment in the children of first year of life in the Russian Federation after the implementation of the newborn universal hearing screening program. The prevalence of hearing loss in children in the first year of life was estimated at 2.5 per 1,000 based on the official statistical data and reports of hearing rehabilitation centres in 2016. A cohort of 405 children born in 2012 was examined at the age from 0 to 4 years of life. Among them 276 children were diagnosed with permanent congenital and prelingual hearing loss. 88% of the cases were bilateral, sensorineural hearing loss confirmed in 84% of the cases. The genetic cause of hearing loss was revealed in 58% of the patients assessed for the presence of GJB2 gene mutations. In preterm infants, the permanent hearing loss was detected in 70% of the cases. The comprehensive audiological assessment before 3 months of life was conducted only in 32% of the children; this finding is not consistent with the international newborn hearing screening recommendations. Only 70% of the cases of congenital and preverbal hearing loss were diagnosed during the first year of life.

Quiet rim driven ventilation fan design

Auxiliary ventilation fans are commonly used as a form of temperature and humidity control of working environments. However, they often generate high noise levels that cause permanent hearing impairment from prolonged exposure. Dominant noise sources from ventilation fans such as noise due to the aerodynamic interaction of the fan with the struts to support the hub motor and the blade-duct tip gap can be eliminated using a rim driven fan. However, tones from blade steady loading and thickness and the broadband airfoil self-noise of the fan are not eliminated. This noise is proportional to the 4-6th power of the tip speed. Hence, the approach here is to design a ring driven ventilation fan that reduces the fan tip speed while optimizing the blade profile to retain aerodynamic performance. The fan design has been 3D printed and implemented using a motor mounting system to validate the predicted performance. The motor mounting system integrates the fan design, a bell mouth shaped duct and a brushless DC motor. The experiments show good agreement with the predicted mechanical power, axial flow, and radiated noise over a range of speeds. Results suggest that a ring driven fan reduces noise while maintaining aerodynamic performance.

Protective Effects of Coadministration of NAC and CoQ10 Against Noise Induced Hearing Loss

Background: Previous studies demonstrated partial attenuation of noise induced hearing loss (NIHL) by N-acetyl-L-cysteine (NAC) or CoQ10 (ubiquinone). Objectives: The present study investigates the protection effect of coadministration of NAC and CoQ10 against NIHL. Methods: In an experimental study in Iran in 2015, a total of 36 male Wistar rats (275 ± 25 g) were divided randomly based on the permuted block design into 6 experimental groups: (I) noise controls, (II) noise and NAC, (III) noise and CoQ10, (IV) noise and CoQ10 and NAC, (V) noise and saline (as vehicle of NAC) and (VI) noise and olive oil (as vehicle of CoQ10). Antioxidants and vehicles were intraperitoneally injected once a day for two days prior to and 1 hour before 102 ± 0.5 dB white noise exposure 8 h/day in 10 executive days and two days after the noise exposure daily. Distortion product otoacoustic emissions were measured one day before and 1, 7 and 21 days after the exposure. Results: The temporary hearing changes that occurred 1-day post exposure were not significantly different in all groups (P > 0.05). The total recovery (between 1 - 21 days after noise exposure) varied by a frequency increase between 1.08 - 19.10 in the noise group compared to 1.75 - 24.5 and 0.62 - 22.08 in animals treated with NAC and the combination of NAC and CoQ10 respectively. The less permanent hearing impairment was observed in noise exposed animals treated with either NAC or both NAC and CoQ10. Conclusions: The effect of coadministration of NAC and CoQ10 was neither additive nor synergic in protecting against NIHL.

Role of Wnt and Notch signaling in regulating hair cell regeneration in the cochlea.

Sensory hair cells in the inner ear are responsible for sound recognition. Damage to hair cells in adult mammals causes permanent hearing impairment because these cells cannot regenerate. By contrast, newborn mammals possess limited regenerative capacity because of the active participation of various signaling pathways, including Wnt and Notch signaling. The Wnt and Notch pathways are highly sophisticated and conserved signaling pathways that control multiple cellular events necessary for the formation of sensory hair cells. Both signaling pathways allow resident supporting cells to regenerate hair cells in the neonatal cochlea. In this regard, Wnt and Notch signaling has gained increased research attention in hair cell regeneration. This review presents the current understanding of the Wnt and Notch signaling pathways in the auditory portion of the inner ear and discusses the possibilities of controlling these pathways with the hair cell fate determiner Atoh1 to regulate hair cell regeneration in the mammalian cochlea.

A programme of studies including assessment of diagnostic accuracy of school hearing screening tests and a cost-effectiveness model of school entry hearing screening programmes.

Identification of permanent hearing impairment at the earliest possible age is crucial to maximise the development of speech and language. Universal newborn hearing screening identifies the majority of the 1 in 1000 children born with a hearing impairment, but later onset can occur at any time and there is no optimum time for further screening. A universal but non-standardised school entry screening (SES) programme is in place in many parts of the UK but its value is questioned. To evaluate the diagnostic accuracy of hearing screening tests and the cost-effectiveness of the SES programme in the UK. Systematic review, case-control diagnostic accuracy study, comparison of routinely collected data for services with and without a SES programme, parental questionnaires, observation of practical implementation and cost-effectiveness modelling. Second- and third-tier audiology services; community. Children aged 4-6 years and their parents. Diagnostic accuracy of two hearing screening devices, referral rate and source, yield, age at referral and cost per quality-adjusted life-year. The review of diagnostic accuracy studies concluded that research to date demonstrates marked variability in the design, methodological quality and results. The pure-tone screen (PTS) (Amplivox, Eynsham, UK) and HearCheck (HC) screener (Siemens, Frimley, UK) devices had high sensitivity (PTS ≥ 89%, HC ≥ 83%) and specificity (PTS ≥ 78%, HC ≥ 83%) for identifying hearing impairment. The rate of referral for hearing problems was 36% lower with SES (Nottingham) relative to no SES (Cambridge) [rate ratio 0.64, 95% confidence interval (CI) 0.59 to 0.69; p < 0.001]. The yield of confirmed cases did not differ between areas with and without SES (rate ratio 0.82, 95% CI 0.63 to 1.06; p = 0.12). The mean age of referral did not differ between areas with and without SES for all referrals but children with confirmed hearing impairment were older at referral in the site with SES (mean age difference 0.47 years, 95% CI 0.24 to 0.70 years; p < 0.001). Parental responses revealed that the consequences to the family of the referral process are minor. A SES programme is unlikely to be cost-effective and, using base-case assumptions, is dominated by a no screening strategy. A SES programme could be cost-effective if there are fewer referrals associated with SES programmes or if referrals occur more quickly with SES programmes. A SES programme using the PTS or HC screener is unlikely to be effective in increasing the identified number of cases with hearing impairment and lowering the average age at identification and is therefore unlikely to represent good value for money. This finding is, however, critically dependent on the results of the observational study comparing Nottingham and Cambridge, which has limitations. The following are suggested: systematic reviews of the accuracy of devices used to measure hearing at school entry; characterisation and measurement of the cost-effectiveness of different approaches to the ad-hoc referral system; examination of programme specificity as opposed to test specificity; further observational comparative studies of different programmes; and opportunistic trials of withdrawal of SES programmes. Current Controlled Trials ISRCTN61668996. This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 20, No. 36. See the NIHR Journals Library website for further project information.

Aetiologic diagnosis of hearing loss in children identified through newborn hearing screening testing.

SUMMARYWith the implementation of universal newborn hearing screening (UNHS) programmes and early diagnosis and treatment of hearing problems, the need has clearly emerged to implement and carry out a systematic and coordinated protocol for the aetiological diagnosis of permanent hearing impairment (PHI). Within the framework of the Italian Ministry of Health project CCM 2013 "Preventing Communication Disorders: a Regional Program for early Identification, Intervention and Care of Hearing Impaired Children", it has been decided to consider the problems relative to aetiological diagnosis of child PHI within UNHS programmes. The specific objective was to apply a shared diagnostic protocol that can identify the cause in at least 70% of cases of PHI. For this part of the project, four main recommendations were identified that can be useful for an efficient aetiological diagnosis in children affected by PHI and that can offer valid suggestions to optimise resources and produce positive changes for third-level audiologic centres.

Achieving effective hearing aid fitting within one month after identification of childhood permanent hearing impairment.

SUMMARYDiagnosis of child permanent hearing impairment (PHI) can be made with extreme timeliness compared to the past thanks to improvements in PHI identification through newborn hearing screening programmes. It now becomes essential to provide an effective amplification as quickly as possible in order to restore auditory function and favour speech and language development. The early fitting of hearing aids and possible later cochlear implantation indeed prompts the development of central auditory pathways, connections with secondary sensory brain areas, as well as with motor and articulatory cortex. The aim of this paper is to report the results of a strategic analysis that involves identification of strengths, weaknesses, opportunities and threats regarding the process of achieving early amplification in all cases of significant childhood PHI. The analysis is focused on the Italian situation and is part of the Italian Ministry of Health project CCM 2013 "Preventing Communication Disorders: a Regional Program for Early Identification, Intervention and Care of Hearing Impaired Children".

Empowering the family during the first months after identification of permanent hearing impairment in children.

SUMMARYThe latest international guidelines highlight the importance of involving the family in the diagnositic and rehabilitation process of children affected by permanent hearing impairment. This emphasises how meaningful this approach is for the development of the deaf child. So far, there is very little evidence about this approach in Italy, and there are still some barriers to its practical management. The aim of this paper is to report the results of a strategic analysis, which identifies the strengths, weaknesses, opportunities and threats of the family empowerment process during early auditory diagnosis and rehabilitation. The audiology programme should have the goal to offer information and support to families in order to achieve a conscious decision about the use and type of auditory prosthesis and rehabilitation choice within three months after audiologic diagnosis. Within the framework of the Ministry of Health project CCM 2013 "Preventing Communication Disorders: a Regional Program for Early Identification, Intervention and Care of Hearing Impaired Children", a group of professionals identified three main recommendations that can be useful to foster the natural communicative development of the child by strengthening the therapeutic alliance and empowerment of the family. The recommendations obtained with this analysis can help to develop new Italian guidelines with the aim to foster natural communicative development of the child by strengthening the therapeutic alliance and empowerment of the family.

Planning early childhood audiologic intervention programs on a regional scale: introduction to an Italian study.

SUMMARYNon-uniform, late, or inappropriate care of childhood with permanent hearing impairment (PHI) predisposes many children to develop communicative- behaviour problems and impaired psychosocial adjustment that can persist in adolescence and adulthood.In March 2014, the CCM (Centro Controllo Malattie or Disease Control Centre) of the Italian Ministry of Health funded a project entitled " Preventing Communication Disorders: a Regional Program for Early Identification, Intervention and Care of Hearing Impaired Children". The project involved 5 tertiary centres with UNHS programs formally approved by the Region. The main purpose of the project is to define and launch an integrated regionally-based public health model for identification, diagnosis and intervention of childhood PHI. The first phase of the project investigated the state of art and produced recommendations for positive changes in identification, diagnosis, therapy and care of childhood PHI in Italy, taking into account diagnostic and treatment innovations, family empowerment, treatment alliance and an interdisciplinary approach. Recommendations drawn from this initial phase will represent the basis for a regional system for early intervention that is validated, integrated and shared between the five regions.

Follow-up of permanent hearing impairment in childhood.

SUMMARYProgrammes for early childhood childhood hearing impairment identification allows to quickly start the appropriate hearing aid fitting and rehabilitation process; nevertheless, a large number of patients do not join the treatment program. The goal of this article is to present the results of a strategic review of the strengths, weaknesses, opportunities and threats connected with the audiologic/prosthetic/language follow-up process of children with bilateral permanent hearing impairment. Involving small children, the follow-up includes the involvement of specialised professionals of a multidisciplinary team and a complex and prolonged multi-faced management. Within the framework of the Italian Ministry of Health project CCM 2013 "Preventing Communication Disorders: a Regional Program for Early Identification, Intervention and Care of Hearing Impaired Children", the purpose of this analysis was to propose recommendations that can harmonise criteria for outcome evaluation and provide guidance on the most appropriate assessment methods to be used in the follow-up course of children with permanent hearing impairment.