A study to evaluate the burden of hearing loss and its correlation with risk factors among high-risk infants at a teaching institution, Jaipur.

Introduction: Hearing loss is a global issue of hearing disability and early detection and rehabilitation of hearing loss are important for the development of speech and language skills in hearing-impaired infants. There are multiple risk factors that aid in hearing loss but some are potential factors that contribute toward hearing loss in infants. The aim of this study was to assess the burden of hearing loss and its correlation with risk factors among high-risk infants at a teaching institution in Jaipur, Rajasthan. Method: This study was carried out after approval of institutional ethics committee on a total of 320 high-risk infants at RUHS College of medical sciences and associated hospitals. Hearing loss was assessed by brainstem evoked response audiometry (BERA). Statistical analysis of data was done by cross-tabulation analysis with Pearson correlation and quantile regression. Results: Out of 320 high-risk infants, 59.69% of infants had normal hearing, 9.09% Unilaterally hearing impaired, 20.31% were bilaterally mild-moderate hearing loss, and 10.94% had severe-profound deafness. The prevalence of important risk factors viz. hyperbilirubinemia, low birth weight, appearance, pulse, grimace, activity, and respiration score, meconium aspiration, respiratory distress, and ventilation greater than five days were 86%, 58.9%, 40%, 36%, 29%, and 22%, respectively. Conclusion: In high-risk infants, hearing loss is a common hearing disorder. Because of this, early diagnosis of hearing loss gives them the best chance of developing functional speech. Brainstem evoked response audiometry is a simple, reliable, and effective technique for the assessment of auditory functions in infants.

Effect of Maternal Diabetes Mellitus on Neonatal Hearing.

Introduction: Gestational diabetes is a potential risk factor for neonatal hearing loss. Increased circulating sugars in mothers during pregnancy can impairs the micro circulation and can cause congenital anomalies of the inner ear resulting in congenital hearing loss. This study attempts to find the incidence of neonatal hearing loss among diabetic mothers. Methodology: This was a case control study with 86 neonates of diabetic mothers as cases and neonates of non diabetic mothers(n = 86) as controls. Antenatal diabetic history and sugar values of mothers were documented. Hearing status of the neonates were tested using DPOAE test and ABR test. DPOAE test was done on 3rd day and those who did not get a positive response underwent 2nd DPOAE and also ABR test if 2nd DPOAE was negative. Results: All neonates underwent DPOAE test and few were lost on follow up. First and second DPOAE showed a statistically significant difference between cases and controls. All babies who underwent ABR test had abnormal waveforms. 98% of cases showed moderate and severe bilateral hearing loss whereas all controls had only mild bilateral hearing loss. Discussion: This study showed a significantly higher percentage of abnormal hearing outcome among neonates of diabetic mothers than non diabetic mothers. This could be because of the toxic effects of maternal hyperglycemia on developing auditory system of the fetus. This study emphasis the need for better glycaemic control in diabetic pregnancy, the importance of early and mandatory hearing screening in newborns of diabetic mothers.

Electrically Evoked Auditory Brainstem Response Using Extracochlear Stimulation at Different Cochlear Sites: A Comparison With Intracochlear Stimulation.

OBJECTIVES: The distribution and extent of excitable spiral ganglion neurons (SGNs) have been investigated using the electrically evoked auditory brainstem response (EABR) during preoperative and perioperative periods. In this study, we investigated the EABR with extracochlear stimulation (eEABR) as a preoperative test to estimate these factors. METHODS: Sixteen male Sprague-Dawley rats were used in this study. Experiments were conducted in nine rats with normal hearing and seven rats that were partially deafened with ouabain treatment. Each experiment involved the following steps: extracochlear stimulating electrode placement at three different sites along the axis of the cochlea and eEABR recordings; cochleostomy and four-channel intracochlear array implantation, followed by EABR recordings with various electrode pair combinations; and after electrophysiological measurements, harvest of the cochleae for histopathological evaluation. The slope characteristics of the amplitude growth function measured from eEABR and EABR, frequency-specific auditory thresholds, and the density of SGNs were compared. RESULTS: Similar trends were observed in slope changes on different sites of stimulation with both types of stimulation in normal-hearing animals-specifically, a monotonically increasing slope with increasing distance between bipolar pairs. In addition, eEABR slopes showed significant correlations with EABR slopes when the expected cochlear regions of stimulation were similar in normal-hearing animals. In partially deaf animals, the auditory thresholds at several frequencies had a significant correlation with the eEABR slopes of each extracochlear electrode at the apical, middle, and basal cochlear positions. This indicated that increasing the regions of cochlear stimulation had a differential impact on eEABR slopes, depending on the neural conditions. CONCLUSION: Our results indicated that eEABR slopes showed significant spatial correlations with the functionality of the auditory nerve. Therefore, eEABR tests at various cochlear positions might be used for estimating the extent of excitable SGNs in cochlear implant candidates prior to implantation.

Evaluation of the maturational auditory process in children with the infection by Zika congenital syndrome / Avaliação do processo maturacional auditivo em crianças portadoras da síndrome da infecção congênita pelo Zika vírus

ABSTRACT Purpose: to analyze the absolute latencies of waves I. III and V and the interpeak intervals I-III. III-V and I-V of the ABR recorded from different age groups of children with congenital zika virus infection and their peers without risk indicators for hearing impairment. Methods: 84 newborns and infants (N=51 study group and N=33 control group) divided into groups with different post-conceptual ages. with the results of their hearing exams analyzed by age group and compared with their peers without other risk indicators for hearing impairment. The assessment of the auditory pathway was conducted through tympanometry. otoacoustic emissions and auditory brain stem responses. Results: only the latency of wave I and the interpeak III-V showed no significant difference between the study and control groups. The absolute latency and interpeak values found in the study group were significantly lower than those found in the control group. Conclusion: the maturation of the brain stem in children with ZIKV infection occurred within normal limits. with no retrocochlear disorders until the age of 5 years.

RESUMO Objetivo: analisar as latências absolutas das ondas I. III e V e os intervalos interpicos I-III. III-V e I-V do Potencial Evocado Auditivo de Tronco Encefálico obtidos em diversos grupos etários de crianças portadoras de infecção congênita por zika vírus e nos seus pares sem indicadores de risco para deficiência auditiva. Métodos: foram recrutados 84 recém-nascidos e lactentes (N=51 grupo de estudo e N=33 grupo controle) separados por grupos com diferentes idades pós-conceptuais. sendo os resultados dos seus exames auditivos analisados por faixa etária e comparados com seus pares sem outros indicadores de risco para deficiência auditiva. A avaliação da via auditiva foi realizada por meio da timpanometria. emissões otoacústicas transientes e potencial evocado de tronco encefálico. Resultados: somente a latência da onda I e o intervalo interpico III-V não apresentaram diferença significante entre grupo de estudo e controle. Os valores de latências absolutas e interpicos encontrados no grupo de estudo foram menores do que os obtidos no grupo controle de forma significativa. Conclusão: a maturação do tronco encefálico nas crianças portadoras de infecção por Zika Vírus ocorreu dentro da normalidade. não apresentando alterações retrococleares até a idade de 5 anos.

Brazilian Society of Otology task force - Vestibular Schwannoma ‒ evaluation and treatment.

OBJECTIVE: To review the literature on the diagnosis and treatment of vestibular schwannoma. METHODS: Task force members were educated on knowledge synthesis methods, including electronic database search, review and selection of relevant citations, and critical appraisal of selected studies. Articles written in English or Portuguese on vestibular schwannoma were eligible for inclusion. The American College of Physicians' guideline grading system and the American Thyroid Association's guideline criteria were used for critical appraisal of evidence and recommendations for therapeutic interventions. RESULTS: The topics were divided into 2 parts: (1) Diagnosis - audiologic, electrophysiologic tests, and imaging; (2) Treatment - wait and scan protocols, surgery, radiosurgery/radiotherapy, and systemic therapy. CONCLUSIONS: Decision making in VS treatment has become more challenging. MRI can diagnose increasingly smaller tumors, which has disastrous consequences for the patients and their families. It is important to develop an individualized approach for each case, which highly depends on the experience of each surgical team.

A machine learning approach for prediction of auditory brain stem response in patients after head-and-neck radiation therapy.

Objective: The present study aimed to assess machine learning (ML) models according to radiomic features to predict ototoxicity using auditory brain stem responses (ABRs) in patients with radiation therapy (RT) for head-and-neck cancers. Materials and Methods: The ABR test was performed on 50 patients having head-and-neck RT. Radiomic features were extracted from the brain stem in computed tomography images to generate a radiomic signature. Moreover, accuracy, sensitivity, specificity, the area under the curve, and mean cross-validation were used to evaluate six different ML models. Results: Out of 50 patients, 21 participants experienced ototoxicity. Furthermore, 140 radiomic features were extracted from the segmented area. Among the six ML models, the Random Forest method with 77% accuracy provided the best result. Conclusion: According to the ML approach, we showed the relatively high prediction power of the radiomic features in radiation-induced ototoxicity. To better predict the outcomes, future studies on a larger number of participants are recommended.

The human neuroprotective placental protein composition suppressing tinnitus and restoring auditory brainstem response in a rodent model of sodium salicylate-induced ototoxicity.

The effect of neuroprotective placental protein composition (NPPC) on the suppression of tinnitus and the restoration of the auditory brainstem response (ABR) characteristics was explored in tinnitus-induced rats. The animals were placed into two groups: (1) the study group, rats received sodium salicylate (SS) at the dose of 200 mg/kg twice a day for two weeks, and then 0.4 mg of the NPPC per day, between the 14th and 28th days, (2) the placebo group, rats received saline for two weeks, and then the NPPC alone between the 14th and 28th days. The gap pre-pulse inhibition of the acoustic startle (GPIAS), the pre-pulse inhibition (PPI), and the ABR assessments were performed on animals in both groups three times (baseline, day 14, and 28). The GPIAS value declined after 14 consecutive days of the SS injection, while NPPC treatment augmented the GPIAS score in the study group on the 28th day. The PPI outcomes revealed no significant changes, indicating hearing preservation after the SS and NPPC administrations. Moreover, some changes in ABR characteristics were observed following SS injection, including (1) higher ABR thresholds, (2) lowered waves I and II amplitudes at the frequencies of 6, 12, and 24 kHz and wave III at the 12 kHz, (3) elevated amplitude ratios, and (4) prolongation in brainstem transmission time (BTT). All the mentioned variables returned to their normal values after applying the NPPC. The NPPC use could exert positive therapeutic effects on the tinnitus-induced rats and improve their ABR parameters.

Hyperacusis in the Adult Fmr1-KO Mouse Model of Fragile X Syndrome: The Therapeutic Relevance of Cochlear Alterations and BKCa Channels.

Hyperacusis, i.e., an increased sensitivity to sounds, is described in several neurodevelopmental disorders (NDDs), including Fragile X Syndrome (FXS). The mechanisms underlying hyperacusis in FXS are still largely unknown and effective therapies are lacking. Big conductance calcium-activated potassium (BKCa) channels were proposed as a therapeutic target to treat several behavioral disturbances in FXS preclinical models, but their role in mediating their auditory alterations was not specifically addressed. Furthermore, studies on the acoustic phenotypes of FXS animal models mostly focused on central rather than peripheral auditory pathways. Here, we provided an extensive characterization of the peripheral auditory phenotype of the Fmr1-knockout (KO) mouse model of FXS at adulthood. We also assessed whether the acute administration of Chlorzoxazone, a BKCa agonist, could rescue the auditory abnormalities of adult mutant mice. Fmr1-KO mice both at 3 and 6 months showed a hyperacusis-like startle phenotype with paradoxically reduced auditory brainstem responses associated with a loss of ribbon synapses in the inner hair cells (IHCs) compared to their wild-type (WT) littermates. BKCa expression was markedly reduced in the IHCs of KOs compared to WT mice, but only at 6 months, when Chlorzoxazone rescued mutant auditory dysfunction. Our findings highlight the age-dependent and progressive contribution of peripheral mechanisms and BKCa channels to adult hyperacusis in FXS, suggesting a novel therapeutic target to treat auditory dysfunction in NDDs.

Mismatch Negativity and Auditory Brain Stem Response in Children with Autism Spectrum Disorders and Language Disorders.

Objective: Language disorders (LD) in autism spectrum disorders (ASD) are highly variable and has a severe impact on the level of functioning in autistic children. Early diagnosis of these language disorders is essential for early interventions for children at risk. The electrophysiological measurements are considered valuable tools for determining language disabilities in children with ASD. This study aimed to study and compare ABR and MMN in autistic children with language disorders. Methods: This study included a group of typically developing children and a group of children diagnosed with autistic spectrum disorders and language disorders. Both groups were matching according to age and gender. After confirming bilateral normal peripheral hearing sensitivity, ABR was done and both absolute and interpeak wave latencies were correlated. MMN using frequency oddball paradigms were also obtained and correlated. Results: More abnormalities were reported in ABR test results in the form of delayed absolute latencies and prolonged interpeak intervals. Also, we reported prolonged latencies of MMN. Consequently, both ABR and MMN are complementary test in evaluating autistic children with language disorders. Conclusion: Our results support the hypothesis of remarkable dysfunction in basic auditory sound processing that may impact the linguistic development of autistic children.

Study of auditory pathways in type 1 diabetes mellitus through brainstem auditory evoked potentials and contralateral acoustic reflex / Estudo das vias auditivas em diabetes mellitus tipo 1 através dos potenciais auditivos evocados de tronco encefálico e reflexo acústico contralateral

ABSTRACT Purpose To investigate the functionalities of the neural pathways through the auditory evoked potentials of the brainstem and the contralateral stapedial acoustic reflexes in normal-hearing individuals with type 1 diabetes mellitus, in order to detect possible alterations in the central auditory pathways. Methods This is a cross-sectional study with a comparison group and a convenience sample, consisting of 32 individuals with type 1 diabetes mellitus and 20 controls without the disease. All subjects had hearing thresholds within normal limits and type A tympanometric curves. The acoustic reflex arc and brainstem auditory potentials were investigated. Statistical analyses were performed using the SPSS 17.0. The Chi-square test, Student´s t-test, and Multiple linear regression were used. Results The auditory thresholds of the acoustic reflex were statistically lower in the group with the disease at frequencies of 0.5 kHz and 1.0 kHz in the left ear (p=0.01 and p=0.01, respectively). The absolute latencies III and V of the auditory potentials of the brainstem in the right ear and V in the left ear were increased in subjects with type 1 diabetes mellitus (p=0.03, p=0.02 and p=0.03, respectively). Conclusion The findings suggest that subjects with type 1 diabetes mellitus are more likely to present alterations in the central auditory pathways, even with auditory thresholds within normal limits.

RESUMO Objetivo Investigar a funcionalidade das vias neurais por meio dos potenciais evocados auditivos de tronco encefálico e os reflexos acústicos estapedianos contralaterais em sujeitos com diabetes mellitus tipo 1 normo-ouvintes, a fim de detectar possíveis alterações nas vias auditivas centrais. Método Trata-se de um estudo transversal com grupo de comparação, e amostra de conveniência, composta por 32 sujeitos com diabetes mellitus tipo 1 e 20 controles sem a doença. Todos os sujeitos apresentavam limiares auditivos dentro dos padrões de normalidade e curva timpanométrica tipo A. Foram investigados o arco-reflexo acústico e os potenciais auditivos de tronco encefálico. As análises dos resultados foram realizadas no SPSS 17.0. Utilizou-se o Teste Qui Quadrado, Teste T de Studant e Regressão linear múltipla. Resultados Os limiares auditivos do reflexo acústico foram estatisticamente menores no grupo com a doença nas frequências de 0,5 kHz e 1,0 kHz na orelha esquerda (p=0,01 e p=0,01, respectivamente). As latências absolutas III e V dos potenciais auditivos de tronco encefálico da orelha direita e V da orelha esquerda estavam aumentadas em sujeitos com diabetes mellitus tipo 1 (p=0,03, p=0.02 e p=0,03, respectivamente). Conclusão Os achados sugerem que sujeitos com diabetes mellitus tipo 1 estão mais propensos a apresentar alterações nas vias auditivas centrais, mesmo com limiares auditivos dentro dos padrões de normalidade.

Brazilian Society of Otology task force - Vestibular Schwannoma - evaluation and treatment

Abstract Objective: To review the literature on the diagnosis and treatment of vestibular schwannoma. Methods: Task force members were educated on knowledge synthesis methods, including electronic database search, review and selection of relevant citations, and critical appraisal of selected studies. Articles written in English or Portuguese on vestibular schwannoma were eligible for inclusion. The American College of Physicians' guideline grading system and the American Thyroid Association's guideline criteria were used for critical appraisal of evidence and recommendations for therapeutic interventions. Results: The topics were divided into 2 parts: (1) Diagnosis - audiologic, electrophysiologic tests, and imaging; (2) Treatment - wait and scan protocols, surgery, radiosurgery/radiotherapy, and systemic therapy. Conclusions: Decision making in VS treatment has become more challenging. MRI can diagnose increasingly smaller tumors, which has disastrous consequences for the patients and their families. It is important to develop an individualized approach for each case, which highly depends on the experience of each surgical team.

Frequency-Following Response and Auditory Behavior in Children with Prenatal Exposure to the Zika Virus

Abstract Introduction Prenatal exposure to the Zika virus can impair neurodevelopment and cause auditory damage. Objective To analyze the frequency-following response (FFR) and the auditory behavior (with the LittlEars® questionnaire) of children with and without prenatal exposure to Zika virus infection. Methods A total of 30 children participated in the present study, divided into 3 groups: 10 children with microcephaly and prenatal exposure to the Zika virus; 10 normocephalic children with prenatal exposure to the Zika virus; and 10 children with no evidence of prenatal exposure to the virus. The FFR test was performed with the /da/ syllable. The LittlEars® questionnaire was used with parents/guardians. Results For the FFR measurements, there was no difference between the groups. The children with exposure to the Zika virus presented a final score in the questionnaire below what is expected from children with normal hearing. A significant difference was observed for the final, semantic, and expressive scores between the group with microcephaly and the other groups. A strong negative correlation was seen between the LittlEars® questionnaire final score and the FFR measurements for the group with microcephaly when compared with the other groups. Conclusion Children exposed to the Zika virus, with and without microcephaly, presented FFR patterns similar to what was seen in children with no evidence of virus exposure. However, they showed signs of immature auditory behavior, suggesting auditory development delay.

Supra-Threshold Hearing Sensitivity Disorders and Mild Permanent Hearing Loss: Neglected Cause of Hidden Hearing Loss and Speech Defects.

Supra-threshold disorders in the form of auditory neuropathy (AN)/auditory dys-synchrony (AD) or central auditory processing disorders (CAPD), a special type of retrocochlear hearing loss; and also children with mild permanent hearing loss (PHL), may be missed on current hearing protocols. Otoacoustic emissions (OAE) and Brain stem evoked response audiometry (BERA), are tests, when used in combination, can indirectly help diagnose the different types of hearing loss. To correlate the parental awareness and the pattern of hearing loss (HL) in children with/without auditory and/or speech problems, using both OAE and BERA as hearing tests for indirect identification of suprathreshold disorders and mild PHL. An Observational Prospective study carried out on 100 children in the age group of 0-5 years, for detection of type of HL by both OAE and BERA and correlating it with parental awareness of HL and speech defects. In 72.22% of children with speech problem only and without any complaints of HL, some form of HL (confirmed HL-OAE refer/BERA fail or auditory neuropathy/auditory dys-synchrony-OAE pass/BERA fail) was diagnosed, whereas 24.07% had no detectable HL on both OAE and BERA pass, and were considered as indirect evidence of CAPD. 3.7% with OAE refer and BERA pass were considered indicative of mild PHL. AN/AD/CAPD/Mild PHL are important cause of speech delay without parental awareness of HL. OAE and BERA together can be used as an indirect evidence of their presence.

Role of Hearing Screening in High-Risk Newborns.

Hearing is one of the very important five senses. The most important period for language and speech development is generally regarded as the first three years of life. For the past 20 years, electrophysiological methods are most commonly used which include otoacoustic emission (OAE) and auditory brain stem response (ABR). Regardless of the screening method chosen, hearing screening, though critical, is only the first stage of a comprehensive early intervention plan. Screening alone is useless unless appropriate diagnostic testing services and high quality amplification and rehabilitation services are in place and are implemented in a timely fashion. Early screening does not substitute for further periodic childhood hearing screening. To screen the newborns which are high risk or born to high risk mother using optoacoustic emission and auditory brain stem response (ABR). Also to co-relate hearing loss with various risk factors involved in pre-natal, natal and post-natal. Methods: we conducted a prospective study with 100 high risk newborns in a tertiary care centre. First, all babies were screened using transient evoked otoacoustic emission(TEOAE). Babies not responsive in this were screening again after 14 days using TEOAE. Babies who were reffered to during this screening with TEOAE were subjected to further screening with ABR to confirm the diagnosis. Out of 100 infants, 73% infants passed first screening by TEOAE whereas 27% failed. those 27 infants which failed were screened after 14 days, of them, 3 (11.1%) infants failed the second screening and were referred. Further screening with BERA was conducted for 3 children who failed the second screening by TEOAE. Of them 1 (33.3%) infant passed the BERA whereas 2 infants failed. Test of significance observed no statistically significant association of OAE with prenatal risk factors in present study (p>0.05). whereas shows highly statistically significant association of OAE with natal (birth asphyxia, NICU admission and Apgar score at 5 minutes) and post natal (viral/bacterial infections) risk factors (p<0.01). New born hearing screening is important in recognizing babies born with congenital hearing loss. The screening protocol using OAE can be used in a two staged screening. This study aimed to detect the congenital hearing loss as early as possible and its association with various risk factors in high risk newborns and role of OAE and ABR as a screening tool. Timely diagnosis and intervention for hearing loss are not the reality throughout India. The population and professionals involved in childcare should be made aware of the impact of hearing loss, this could result in better outcome of neonatal hearing screening programs.

Frequency-Following Response and Auditory Behavior in Children with Prenatal Exposure to the Zika Virus.

Introduction Prenatal exposure to the Zika virus can impair neurodevelopment and cause auditory damage. Objective To analyze the frequency-following response (FFR) and the auditory behavior (with the LittlEars ® questionnaire) of children with and without prenatal exposure to Zika virus infection. Methods A total of 30 children participated in the present study, divided into 3 groups: 10 children with microcephaly and prenatal exposure to the Zika virus; 10 normocephalic children with prenatal exposure to the Zika virus; and 10 children with no evidence of prenatal exposure to the virus. The FFR test was performed with the /da/ syllable. The LittlEars ® questionnaire was used with parents/guardians. Results For the FFR measurements, there was no difference between the groups. The children with exposure to the Zika virus presented a final score in the questionnaire below what is expected from children with normal hearing. A significant difference was observed for the final, semantic, and expressive scores between the group with microcephaly and the other groups. A strong negative correlation was seen between the LittlEars ® questionnaire final score and the FFR measurements for the group with microcephaly when compared with the other groups. Conclusion Children exposed to the Zika virus, with and without microcephaly, presented FFR patterns similar to what was seen in children with no evidence of virus exposure. However, they showed signs of immature auditory behavior, suggesting auditory development delay.

Integration of Vestibular and Auditory Information in Ontogenesis.

BACKGROUND: We analyzed the hypothesis that the vestibular and auditory systems are integrative functions. METHODS: The study involved 383 children (5.5 ± 2.4 years old). We assessed the conduct of auditory information by recording the auditory brain stem response (ABR), post-rotational nystagmus (PRN), and cervical vestibular evoked myogenic potentials (cVEMP), and calculated the integration of the parameters. All procedures were carried out using the JACOBI 4 software package. RESULTS: We have found out that PRN, ABR, and cVEMP represent three different groups of integrative functions, each of which is conditioned by its own integrative mechanism. We have proven that PRN and ABR are associated with age, but no relationship was found between cVEMP and age. CONCLUSION: According to our data, the severity of ABR and PRN depended on age, while cVEMP was not associated with age. The functional immaturity of the child's vestibular system, which probably arose in utero, often becomes apparent only at school when reading and writing must be mastered. These skills require maturity of both the vestibule ocular and vestibule spinal functions of the vestibular system.

The safety and efficacy of a nurse-led sedation service using Chloral Hydrate for auditory brainstem response testing.

BACKGROUND: There is a growing number of pediatric procedures requiring sedation outside the operating room. Among these are auditory brainstem response (ABR) tests, the gold standard for objective hearing evaluation in infants and toddlers. Recently, a nurse-led pediatric sedation service based on a structured protocol has been developed for ABR testing. OBJECTIVES: To retrospectively analyze the safety and efficacy of the pediatric nurse-led sedation protocol (PNLSP) in a tertiary medical center using Chloral Hydrate (CH) in children undergoing ABR testing. METHODS: Data from medical charts of children who underwent sedation for ABR testing between January 2014 and December 2017, were retrieved. Analysis of sedation success/failure rates, sleep induction time (SIT), sleep duration time (SDT), and adverse events (AE), was performed. FINDINGS: 1348 children with a mean age of 13.4 months (range 3-42 months), classified by the American Society of Anesthesiologists Physical Status Classification System (ASA score) 1-3, were included in the analysis. All children received a fixed dose of 75 mg / kg CH orally or rectally. Sedation success rate was 98.7% and enabled completion of ABR testing. Failure to sedate was evident in 17 children (1.3%), all classified as ASA score 1-2. Median SIT and SDT were 25 and 100 min, respectively. Mild AE occurred in 9 children (0.67%), none of which required further intervention. CONCLUSIONS: Findings support the use of a structured PNLSP using CH as safe and efficient. The suggested protocol is an effective alternative for general anesthesia (GA) for ABR testing in healthy young children.

Changes in the Area Adjacent to the Internal Receiver-Stimulator of Cochlear Implant: A Retrospective Study.

BACKGROUND: In some patients with cochlear implants, bony resorption at the internal receiver- stimulator site can be observed on postoperative computed tomography. Therefore, it is essential to elucidate the effects of the internal receiver-stimulator on the scalp and bony bed over time. OBJECTIVE: We aimed to evaluate how the internal receiver-stimulator of a cochlear implant device changed the thickness of the surrounding scalp and skull over time using computed tomography. METHODS: This retrospective study evaluated patients who underwent cochlear implantation and received two computed tomography scans postoperatively for different indications at a tertiary referral centre. The main outcomes were scalp thickness and bony bed depth. RESULTS: Fourteen ears were included in this study. There was very good inter-rater reliability among the two readers who evaluated the computed tomography of the included patients, with a Cronbach's alpha of 0.94. The mean scalp thickness over the internal receiver-stimulator was 6.02 (+/-2.4) mm in the first scan and decreased with no significant change to 5.62 mm (+/-1.64) in the second scan (p = 0.59, paired t-test). The mean depth of the bony bed increased significantly from 1.39 mm (+/-0.93) to 2.62 mm (+/-1.24) (p = 0.03). CONCLUSION: There was no change in the thickness of the scalp overlying the internal receiver-stimulator indicating that the scalp was more resistant than the bony skull to the tensile pressure exerted by the internal receiver-stimulator. In contrast, the bony bed depth of the internal receiver-stimulator increased over time. This can result in decreased internal receiver-stimulator protrusion and decreased risk of device displacement and migration.

Frequency-Following Response (FFR) em usuários de implante coclear: uma revisão sistemática dos parâmetros de aquisição, análise e resultados / Frequency-Following Response (FFR) in cochlear implant users: a systematic review of acquisition parameters, analysis, and outcomes

RESUMO Objetivo Caracterizar os parâmetros de aquisição, análise e resultados do exame Frequency Following Response (FFR) em usuários de implante coclear. Estratégia de pesquisa As buscas foram realizadas nas bases Cochrane Library, Literatura Latino-Americana e do Caribe em Ciências da Saúde (LILACS), Ovid Technologies, PubMed, SciELO, ScienceDirect, Scopus, Web of Science e na literatura cinzenta. Critérios de seleção Foram incluídos estudos sobre o FFR em usuários de implante coclear ou que os comparassem à indivíduos com audição normal, sem restrição de idade. Foram excluídos estudos secundários e experimentais. Não houve restrição de idioma e ano de publicação. Análise dos dados Os dados foram analisados e redigidos de acordo com as etapas do Preferred Reporting Items for Systematic Reviews and Meta-Analyse (PRISMA) 2020. Para análise da qualidade metodológica foi utilizado o instrumento Joanna Briggs Institute Critical Appraisal Checklist for Analytical Cross Sectional Studies. As divergências foram resolvidas por um terceiro pesquisador. Resultados Seis estudos atenderam aos critérios de inclusão. Apenas um estudo foi do tipo comparativo com grupo controle de indivíduos com audição normal. As variações nos parâmetros de aquisição foram comuns e as análises predominaram no domínio do tempo. Usuários de implante coclear apresentaram diferenças nos resultados do FFR quando comparados a indivíduos com audição normal, considerando a literatura existente. A maioria dos artigos teve baixa qualidade metodológica. Conclusão Não existe padronização de um protocolo de aquisição e análise para o FFR em usuários de implante coclear. Os resultados são de alto risco de viés.

ABSTRACT Purpose To characterize the acquisition parameters, analysis, and results of the frequency-following response (FFR) in cochlear implant users. Research strategies The search was conducted in Cochrane Library, Latin American and Caribbean Health Sciences Literature (LILACS), Ovid Technologies, PubMed, SciELO, ScienceDirect, Scopus, Web of Science, and gray literature. Selection criteria Studies on FFR in cochlear implant users or that compared them with normal-hearing people, with no restriction of age, were included. Secondary and experimental studies were excluded. There was no restriction of language or year of publication. Data analysis The data were analyzed and reported according to the stages in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), 2020. The methodological quality was analyzed with the Joanna Briggs Institute Critical Appraisal Checklist for Analytical Cross-Sectional Studies. Divergences were solved by a third researcher. Results Six studies met the inclusion criteria. Only one study was comparative, whose control group comprised normal-hearing people. The variations in acquisition parameters were common and the analysis predominantly approached the time domain. Cochlear implant users had different FFR results from those of normal-hearing people, considering the existing literature. Most articles had low methodological quality. Conclusion There is no standardized FFR acquisition and analysis protocol for cochlear implant users. The results have a high risk of bias.

Intranasal Dexmedetomidine increases the successful sedation of children with autism for out-patient auditory brainstem response hearing tests.

INTRODUCTION: The auditory brainstem response (ABR) hearing test can be challenging in children with autism spectrum disorder (ASD) due to the inherent behavioral challenges associated with this condition. To attempt to increase our success in sedating ASD patients, we added the use of intranasal Dexmedetomidine (Dexmed) to be used alone or with oral Chloral Hydrate (CH) in an ambulatory care setting, with monitoring by a specialist nurse. OBJECTIVES: To determine the success and safety of a protocol for ABR testing performed under sedation with intranasal Dexmed and oral chloral hydrate in ASD patients. To compare the success rate, the occurrence of adverse events and time needed to initiate ABR between Dexmed-CH protocol and previous CH-alone protocol in ASD patients. METHODS: Retrospective review. ASD patients in Dexmed-CH sedation protocol were age- and sex-matched to ASD patients who underwent CH-alone sedation protocol, for comparison. RESULTS: 74 ABR records in ASD children were included, 37 patients using Dex-CH protocol and 37 patients using CH-alone protocol. In the Dexmed-CH protocol group, Dexmed was used in 2 different ways: alone as a first choice in patients who refused to swallow CH (9/37), or combined with CH as a rescue (28/37). Under this sedation protocol, 89% of the attempted ABRs were completed successfully with no major adverse effects. In comparison, in ASD patients sedated using the protocol of CH-alone, the success rate significantly lower (69% vs. 89%). The time needed to initiate the test was not significantly different. CONCLUSION: The use of intranasal Dexmed by itself or in combination with CH was a safe and reliable method of performing sedated ABR in ASD patients. Modifying our previous oral CH protocol to include intranasal Dexmed, substantially improved our success rate of sedation in ASD patients in an ambulatory setting. This study may be of significant value to centers worldwide exploring alternatives to general anesthesia for ABR testing in ASD patients.