Significant Hearing Impairment Research Articles

Cerebral venous congestion alters CNS homeostatic plasticity, evoking tinnitus-like behavior

BackgroundBrain function and neuronal activity depend on a constant supply of blood from the cerebral circulation. The cerebral venous system (CVS) contains approximately 70% of the total cerebral blood volume; similar to the cerebral arterial system, the CVS plays a prominent role in the maintenance of central nervous system (CNS) homeostasis. Impaired venous autoregulation, which can appear in forms such as cerebral venous congestion, may lead to metabolic abnormalities in the brain, causing severe cerebral functional defects and even chronic tinnitus. However, the role of cerebral venous congestion in the progression of tinnitus is underrecognized, and its pathophysiology is still incompletely understood. This study elucidated the specific pathogenetic role of cerebral venous congestion in the onset and persistence of tinnitus and the possible neurophysiological mechanisms.ResultsWe found that a rat model of cerebral venous congestion exhibited tinnitus-like behavioral manifestations at 14 days postoperatively; from that point onward, they showed signs of persistent tinnitus without significant hearing impairment. Subsequent neuroimaging and neurochemical findings showed CNS homeostatic plasticity disturbance in rats with cerebral venous congestion, reflected in increased neural metabolic activity, ultrastructural synaptic changes, upregulated synaptic efficacy, reduced inhibitory synaptic transmission (due to GABA deficiency), and elevated expression of neuroplasticity-related proteins in central auditory and extra-auditory pathways.ConclusionCollectively, our data suggest that alternations in CNS homeostatic plasticity may play a vital role in tinnitus pathology caused by cerebral venous congestion. These findings provide a new perspective on tinnitus related to cerebral venous congestion and may facilitate the development of precise interventions to interrupt its pathogenesis.

Impact on Hearing Among SARS COV-2 Infected Adults and Children Born to Gestational COVID-19 Infected Mothers: A Prospective Case Control Study.

SARS COV 2 infection affects primarily the respiratory system and various organs in humans is responsible for higher mortality secondary to cytokine storm during the COVID-19 pandemic. It affects the internal auditory system is responsible for Sensory neural hearing loss in adults as well as children born to COVID-19 infected mothers. This study was aimed to detect the pattern of hearing loss in COVID-19 infected adults and pattern of hearing loss in children born to gestational COVID-19 infected mothers. Fifty asymptomatic RT-PCR COVID-19 infected adults and age, sex matched healthy controls were evaluated for audiological profile using Pure Tone Audiometry (PTA). Children born to COVID-19 infected mothers were tested using Transient product otoacoustic emissions and click-evoked auditory brainstem responses (ABRs) compared with children born to non-COVID mothers. PTA auditory profile of COVID-19 infected adults on day 7 had 30% (16 out of 50) significant high frequency sensory neural hearing impairment for 4000Hz (p value 0.003), 6000Hz (p value 0.001), 8000Hz (p value 0.001). Repeat PTA testing on day 30 showed normal hearing. Whereas in children, 40% (n = 20) born to COVID-19 infected mothers had OAE as "Refer". BERA (ABRs) testing of that OAE "Refer" children revealed 30% (n = 6) hearing impairment. COVID-19 infection cause transient type of high frequency sensory neural hearing loss in adults. Whereas in children born to COVID-19 infected mothers there is risk of developing permanent, progressive or long-standing transient type of sensory neural hearing loss.

Ototoxicity associated with high-dose carboplatin for patients with previously treated germ cell tumors.

High-dose carboplatin is an essential part of curative high-dose chemotherapy (HDCT) for patients with previously treated germ cell tumors (GCTs). Although hearing loss (HL) is a known side effect of HDCT, data on its severity and characteristics are limited. Eligible patients received HDCT for GCTs from 1993 to 2017 and had audiograms before and after HDCT. HL severity was classified by American Speech-Language-Hearing Association criteria, and mean change in hearing threshold at each frequency (0.25-8kHz) was estimated from pre- to post-HDCT and between HDCT cycles. Of 115 patients (median age, 32 years), 102 (89%) received three cycles of HDCT. Of 106 patients with normal hearing to mild HL in the speech frequencies (0.5-4kHz) before HDCT, 70 (66%) developed moderate to profound HL in the speech frequencies after HDCT. Twenty-five patients (22%) were recommended for hearing aids after HDCT. Patients with moderate to profound HL isolated to the higher frequencies (6-8kHz) before HDCT were more likely to develop moderate to profound HL in the speech frequencies after HDCT (94% vs. 61%; p=.01) and to be recommended for hearing aids (39% vs. 18%; p=.05). HL was frequent after HDCT for GCTs, with most patients developing at least moderate HL in the speech frequencies and approximately one in five recommended for hearing aids. Moderate to profound HL isolated to high frequencies at baseline was predictive of more clinically significant hearing impairment after HDCT. Some patients with germ cell tumors, the most common malignancy in adolescent and young adult men, are not cured with standard-dose chemotherapy and require high-dose chemotherapy (HDCT). Using detailed hearing assessments of patients receiving HDCT, we found that most patients developed significant hearing loss and that one in five needed hearing aids. Thus, strategies to reduce this side effect are urgently needed, and all patients receiving HDCT should have a hearing test after therapy.

Evaluation of Montreal Cognitive Assessment (MoCA) Administered via Videoconference

ObjectivesTelemedicine provides much potential for promoting health care. The Montreal Cognitive Assessment (MoCA) is a screening tool for identifying mild cognitive impairment. This study aims to evaluate the agreement between MoCA assessed face-to-face vs via videoconference using a mobile phone. DesignA randomized crossover study. Setting and ParticipantsA randomly selected sample of patients admitted to the geriatric rehabilitation department in a large tertiary medical center in 2021-2022. MethodsThe MoCA was conducted twice for each patient, with a 10- to 20-day interval between assessments. To avoid a learning effect, alternate MoCA versions were used for each patient. Intraclass correlation coefficient (ICC), kappa, weighted kappa, and the Bland-Altman plot were used to evaluate the agreement between administration methods. To identify variables associated with low agreement, data on participant characteristics, order of administration methods, and test versions were collected, and univariate and multivariable analyses were performed. ResultsForty-four patients were included in the study. The median age was 83 years [interquartile range (IQR 76-87)] and 75% were females. Median overall MoCA score was 24 points (IQR 21-26) when administered face-to-face, and 23.5 points (IQR 21-26) via videoconference. Excellent agreement (ICC = 0.89) was observed in the total MoCA score. Moderate-substantial agreement was observed in subsection scores (kappa 0.436-0.686), except for the language subsection where fair agreement was observed (kappa 0.331). Anxiety was assessed by Hospital Anxiety and Depression Scale and associated with lower agreement (ICC = 0.76 in patients with anxiety vs ICC = 0.92 in patients without anxiety). None of the other studied variables were associated with a difference between administration methods. Conclusions and ImplicationsConducting a MoCA via videoconference using a mobile phone is another method of providing medical care to people without significant visual or hearing impairment that restricts their use of a mobile phone, during routine times and in emergencies where social distancing is needed.

Influence of clinical and neurophysiological parameters on the function outcome of the facial nerve after vestibular schwannoma surgery

Introduction: Vestibular schwannomas are benign neoplasms of the nerve seath, and they represent the third most common endocranial tumour, following the meningioma and the pituitary adenomas. The primary symptoms of vestibular schwannomas are hearing loss, tinnitus as well as a balance disorder. The therapy of vestibular schwannoma consists of observation, surgery and radiosurgery. The majority of patients who are good candidates for surgery are already affected by significant hearing impairment, thus one of the primary goals of the surgery is the preservation of facial nerve function. Aim: To analyze the outcome of facial nerve function one-year post-surgery using clinical and neuropsychological parameters. Material and methods: This study analyzed the patient's clinical status on admission along with the neuroradiological characteristics of tumours and the neurophysiological intraoperative parameters and their effect on the facial nerve function in the early postoperative period as well as one year after the surgery using the House–Brackmann scale. Results: A total of 30 patients who underwent surgery from January 1st 2015 to December 31st 2018 at the Clinical Centre of Serbia, Neurosurgery Clinic for vestibular schwannomas were examined. The median age of the patients was 51 years. Hearing loss was present in all patients. Sensitivity drop in the innervation region of n. trigeminus was present in 7 (23.3%) patients, as was tinnitus. Cerebellar symptomatology (76%) was present in the highest percentage of patients. Conclusion: We can conclude that the most important aspects of the facial nerve function are the preoperative state of the facial nerve and the electrophysiological parameters. Although the radical procedure of surgery led to an immediate postoperative outcome, it was not significant for the ultimate outcome of treatment. Thus, radical surgery may be considered to carry the same risk of definitive impairment of the facial nerve function, just like a combination treatment with subtotal resection and stereotaxic radiosurgery.

Audiometric Profile of Patients on Treatment for Drug-Resistant Pulmonary Tuberculosis in Owerri, South-East Nigeria.

Background: Tuberculosis is an existential medical challenge in certain parts of the world necessitating global efforts. Perhaps more challenging is the treatment of drug-resistant forms of the disease as this requires use of second line drugs, predominantly potentially ototoxic aminoglycosides. The hearing impairment so caused, besides constituting social disability, can impair compliance and have far-reaching consequences. This study aimed at assessing the hearing patterns of patients on treatment for drug-resistant pulmonary tuberculosis to determine if, and to what extent their treatment affected their hearing status. Patients and method: The study was an 18-month prospective analysis of consecutive newly diagnosed drug-resistant pulmonary tuberculosis patients in a tertiary hospital in Owerri, Nigeria. Baseline audiometry was conducted on the patients with subsequent monthly audiometry for 3 months during treatment. A control group drawn from normal population and matched for age and sex with the study group was recruited and audiometry performed on the participants in similar pattern. The audiometric patterns of both groups were analyzed and compared using Statistical Package for Social Sciences (SPSS) version 20.0 software for Windows. Statistical significance was set at p< 0.05. Results: Thirty-eight (38) patients treated for drug-resistant pulmonary tuberculosis completed the study alongside thirty-eight (38) control subjects with M:F ratio was 1.53:1. The baseline prevalence of hearing impairment of any sort was 73.7% and 68.4% among the test and control groups respectively, whereas after three months it was 89.5% and 68.4% respectively. The cumulative incidence of hearing loss over three months was 15.8% and 0% respectively. This difference was statistically significant. Conclusion: Treatment of drug-resistant tuberculosis with second line drugs can lead to significant hearing impairment within the first three months of treatment.

A Randomized Clinical Trial of Gokshuradi Ghan Vati and Gokshuradi Rasayana Churna Along with Swarjikadya Taila Karna Pichu in the Management of Karnasrava with Special Reference to Chronic Suppurative Otitis Media

Karnasrava means flow, oozing, dropping, exudate or discharge through ear. Karnasrava correlates in modern science with C.S.O.M. C.S.O.M. are a chronic inflammation of the middle ear which is the result of an initial episode of acute otitis media and characterized by recurrent discharge from the middle ear through a tympanic perforation. According to WHO prevalence of c.s.o.m. involves 65-330 million individuals with draining ears, 60% of whom (39-200 million) suffers from significant hearing impairment. Material and Method: The present study is done with 30 patients of Karnasrava divided into two groups, 15 patients were treated with Gokshuradi Ghan Vati along with Swarjikadya Taila Karna Pichu rest 15 were treated with Gokshuradi Rasayana Churna along with Swarjikadya Taila Karna Pichu. Result: It showed that Gokshuradi Ghana vati along with Swarjikadya Taila Karna Pichu showed slightly significant as compared to Gokshuradi Rasayana Churna along with Swarjikadya Taila Karna Pichu. Discussion: Swarjikadya Taila is acts as Sthanika Snehana and Swedana, thus causes increased local warming, pseudo-inflammation and increased blood circulation there by helping in better absorption to affected site. Most of the drugs of Gokshuradi Ghana Vati have Rasayana, Kasa-Shwashara, Vedanasthapana, Shulaprashmana, Shothahara, Balya, Vranashodhana, Vranaropana, Krimighna, Deepana, Pachana properties. Conclusion: Both groups showed good result in the management of Karnasrava but Gokshuradi Ghan vati along with Swarjikadya taila Karna pichu showed slightly significant as compared to Gokshuradi Rasayana Churna along with Swarjikadya Taila Karna Pichu.

Hearing Loss After COVID-19 Vaccines: A Systematic Review and Meta-Analysis

ABSTRACT. Background: Hearing loss is generally classified as conductive hearing loss (CHL) and sensory-neural hearing loss (SNHL). It has been reported that COVID-19 infection may affect the vestibular-hearing system causing dizziness, tinnitus, vertigo, and hearing impairment. However, other studies reported that COVID-19 did not lead to significant hearing impairment. Many studies in the literature have reported hearing loss as a complication of COVID-19 vaccines. However, no systematic review or meta-analysis summarizes the literature on this topic.   Method: We performed a comprehensive search for the following databases: PubMed, Cochrane (Medline), Web of Science, and Scopus. All studies published in English till October 2022 were included. These include case reports, case series, prospective and retrospective observational studies, and clinical trials reporting hearing loss following COVID-19 vaccines. Newcastle Ottawa scale (NOS) was used to assess the risk of bias for observational studies. NIH tools were used for non-controlled before and after clinical trials and case reports and case series. A third author solved any disagreements. We analyzed the data using SPSS Software version 26.   Results: A total of 630 patients were identified, with a mean age of 57.3 that ranged from 15 to 93 years old. The majority of the patients were females, 339 (53.8%). In addition, 328 out of 609 vaccinated patients took the Pfizer-BioNTech BNT162b2 vaccine, while 242 (40%) took the Moderna COVID-19 vaccine. The mean time from vaccination to hearing impairment was 6.2, ranging from a few hours to one month after the last dose. Most patients reported unilateral sensorineural hearing loss post-vaccination 593 (94.1%). In order to report the fate of cases, a follow-up was initiated with a mean of 15.6 and a range of 2 to 63 days after the initiation of the treatment. A total of 20 patients were fully recovered, and 11 reported no response. Three out of 328 patients who took the Pfizer-BioNTech BNT162b2 vaccine fully recovered, while five reported partial recovery. According to the chi-squared test, there is a statistically significant difference between patients in terms of fate and the type of COVID-19 vaccination (P-value = 0.001) while reporting no significant difference in dose number prior to the onset of the symptoms (P-value = 0.65) and gender (P-value = 0.4). The ANOVA test was conducted to compare vaccine types and the number of doses in terms of mean time from vaccination to hearing impairment onset. The results found a significant difference between vaccine types (P-value < 0.000) while showing no significance in terms of the number of doses prior to the onset (P-value = 0.6).   Conclusion: There is a statistically significant difference between patients in terms of fate and the type of COVID-19 vaccination while reporting no significant difference in dose number prior to the onset of the symptoms and gender. Further, we concluded that there is a significant difference between vaccine types while showing no significance in terms of the number of doses prior to the onset.

Hearing rehabilitation and microbial shift after middle ear surgery with Vibrant Soundbridge in patients with chronic otitis media

IntroductionPatients with otitis media (OM) encounter significant functional hearing impairment with conductive, or a combined hearing loss and long-term sequelae involving impaired speech/language development in children, reduced academic achievement and irreversible disorders of middle and inner ear requiring a long time therapy and/or multiple surgeries. In its persistent chronic form, Otitis media (COM) can often only be treated by undergoing ear surgery for hearing restoration. The persistent inflammatory reaction plays a major role, often caused by multi-resistant pathogens in the ear. Herein, we present outcomes of patients implanted with currently the only FDA approved active Middle Ear Implant Vibrant Soundbridge (VSB), suffering from persistent COM.MethodsThe study enrolled 42 patients, treated by performing middle ear (ME) surgery to different extents and implanted with the VSB to various structures in the ME. Included were 17 children and 25 adults that had recurrent and/or persisting OM and significant hearing loss. Preoperative and postoperative patients' audiometric data were evaluated and the benefit with VSB assessed using the Glasgow Benefit Inventory for adults and pediatric cohorts. The microbial spectrum of pathogens was assessed before and after surgery, exploring the colonization of the otopathogens, as well as the intestinal microbiome from individually burdened patients.ResultsThe mean functional gain is 29.7 dB HL (range from 10 to 56.2 dB HL) with a significant improvement in speech intelligibility in quiet. Following VSB implantation, no significant differences in coupling were observed at low complication rates. Postoperatively patients showed significantly increased benefit with VSB compared to the untreated situation, including less otorrhea, pain, medical visits, and medication intake, with no recurrent OM and significant bacterial shift in otopathogens. The analysis of the intestinal microbiome displayed a high abundance of bacterial strains that might be linked to chronic and persistent inflammation.ConclusionsFunctional ear surgery including rehabilitation with a VSB in patients suffering from COM present to be safe and effective. The successful acceptance accompanied by the improved audiological performance resulted in significant benefit with VSB, with a shift in the ear pathogens and altered microbiome and thus is a great opportunity to be treated.

Screening for Hearing Impairment in High-Risk Neonates in a Rural Tertiary Care Center

Introduction: Among the many congenital problems, loss of hearing is one of the most common treatable diseases. Hearing loss in early life can have deleterious effects on the child's psychosocial, scholastic, and social-emotional development. Aims: The aim of this study was to estimate the incidence of neonatal hearing loss in high-risk neonates admitted in a rural tertiary care center. To determine the risk factors predictive of hearing impairment in these neonates. Materials and Methods: About 200 high-risk neonates were included in the study. The first screening by otoacoustic emission (OAE) was conducted before the neonate's discharge from the hospital. If it failed, OAE was repeated after 4 weeks or at the first immunization visit. If it again failed, then Brainstem Evoked Response Audiometry (BERA) was conducted within no more than 3 months. Statistical Analysis Used: It was performed using IBM SPSS Statistics (IBM SPSS Version 28.0. Armonk, NY). The Chi-square test was used to calculate the P value. P < 0.05 was considered statistically significant. Results: In the initial screening, 49 out of 200 high-risk neonates had referred OAE. Out of 49, 20 failed in repeat OAE. Out of these 20 neonates, hearing loss was confirmed in 15 neonates (7.5%) by BERA. The risk factors most commonly associated with hearing loss in the present study were neonatal intensive care unit admission >24 h (7%), hyperbilirubinemia (3%), meningitis (3%), and ototoxic drugs (3%). In the neonates who had hearing loss (15), 93.33% were having more than one risk factor. Conclusions: Our study concludes that there is significant hearing impairment in high-risk neonates. Screening for hearing loss and early identification is needed to modulate the period of neural plasticity, preventing them to banish into a world of social isolation, and educational malaise. The health-care facilities in rural regions have limited settings. Hence, at least a targeted screening is recommended for early detection of hearing loss and rehabilitation.

Auditory function assessment in patients with chronic obstructive pulmonary disease.

Chronic obstructive pulmonary disease is a multisystem disease with multiple comorbidities. Hearing is dependent on the cochlear functions that may be affected by oxygenation. Affection of hearing is problematic and represents a major concern that should be seriously investigated as an important comorbidity in chronic obstructive pulmonary disease patients. To assess auditory status among chronic obstructive pulmonary disease patients. The current study was carried out at Al-Azhar University Hospitals, Cairo, from 1 August 2021 to 2022, including 120 participants. In addition to the control group (60 healthy participants), there were two study groups: chronic obstructive pulmonary disease patients with respiratory failure group (30 patients) and non-respiratory failure group (30 patients). Hearing functions were studied using pure tone audiometry, and auditory brain stem response. There was statistically significant hearing impairment in chronic obstructive pulmonary disease patients in comparison to control group. The hearing impairment was more significant in chronic obstructive pulmonary disease with respiratory failure group in comparison to chronic obstructive pulmonary disease without respiratory failure group. The auditory impairment shows a negative interrelationship with oxygen tension (PaO2) and a positive interrelationship with the smoking index. Hearing affection was meaningfully higher among chronic obstructive pulmonary disease patients and more prominent in patients with respiratory failure. Hypoxia results in deterioration of pure tone audiometry and increased absolute and interpeak latencies in auditory brain stem response. At every frequency, the mean pure tone audiometry thresholds were higher for chronic obstructive pulmonary disease groups than control group albeit remaining in the mild to moderate area of hearing loss. Retro-cochlear affection was suggested among patients with chronic obstructive pulmonary disease as evidenced with the prolongation of auditory brain stem response waves latencies.

The Efficacy of Open Mastoidectomy Versus Mastoidectomy with Temporalis Fascia Flap Obliteration

Objective To compare the efficacy of open mastoidectomy versus mastoidectomy with temporalis fascia flap obliteration in achieving postoperative dry ear chronic suppurative otitis media (CSOM) is a perforated tympanic membrane with persistent drainage of pus from the middle ear lasting more than 2-weeks. The global burden of illness from CSOM is estimated to involve about 65 to 330 million individuals with draining ears, 60% of them suffer from significant hearing impairment. Ninety (90) percent of burden is borne by developing countries, in Southeast Asia, the Western region of Africa. CSOM can occur with or without cholesteatoma, and the clinical history of both conditions can be very similar. The treatment plan for cholesteatoma always includes tympanomastoid surgery with medical treatment as an adjunct. The treatment plan for cholesteatoma always includes tympanomastoid surgery. After mastoidectomy the otologists facing mastoid cavity related problems such as otorrhoea, hearing loss. A variety of techniques have been proposed to perform obliteration. Methods Study design Randomized Controlled Trial. Setting Department of ear, nose, and throat (ENT), Head & Neck Surgery, Saidu Group of Teaching Hospital, Swat, Khyber Pakhtunkhwa, Pakistan. Duration of study From Jan, 2019 to 17 July, 2021. Sample size Randomly assigned patients with evidence of atticoantral disease to two groups, 47 in each group. After canal wall down mastoidectomy in Group A cavity left without obliteration, in Group B a superior based vascularized temporalis facial flap was used to obliterate the resultant mastoid cavity and they were followed up to 8-weeks. Results As per efficacy of both groups is concerned, in Group A, 34 (36.17%) patients had achieved post-operative dryness on 8th week of mastoidectomy whereas in Group B, 40 (42.55%) patients achieved post-operative dryness of ear on 8th week subject to mastoidectomy with temporalis fascia flap obliteration. (p value=0.130). Conclusion Patients who underwent mastoidectomy with temporalis fascia flap obliteration yielded better results in comparison to patients who underwent open mastoidectomy. Further the common organism were found in our region Staph Aureus and Bacteriodes and Proteus mirabilis.

Neurobiological Signatures of Auditory False Perception and Phantom Perception as a Consequence of Sensory Prediction Errors.

Simple SummaryThe principle of Bayesian inference provides a theoretical framework for stable perception in numerous tasks, including sensory–perceptual tasks, sensorimotor, and motor tasks. Efference copy (EC) signals enable organisms to reduce cognitive loading by decreasing the sensory processing of their own actions. In the auditory domain, the sensorimotor prediction error is responsible for false perceptions, such as auditory hallucinations in schizophrenia, while sensory prediction error also leads to auditory phantom perception such as tinnitus. Attenuation of the N1 component in event-related potentials has been suggested as evidence for the integrity of the EC mechanism. The current study investigated the EC mechanism in auditory false perception and phantom perception as a consequence of sensory prediction errors. N1 attenuation failures were present in tinnitus patients with significant hearing impairment and in those with schizophrenia, indicating that phantom perception after sensory deprivation might lead to impairment in the EC mechanism. However, the corresponding neural representation with spatiotemporal patterns presented differently between patients with schizophrenia and tinnitus. Although the present study had several constraints, the results provide a new perspective on neurobiological aspects of abnormal auditory perception resulting from deficits in predictive coding.In this study, we hypothesized that top-down sensory prediction error due to peripheral hearing loss might influence sensorimotor integration using the efference copy (EC) signals as functional connections between auditory and motor brain areas. Using neurophysiological methods, we demonstrated that the auditory responses to self-generated sound were not suppressed in a group of patients with tinnitus accompanied by significant hearing impairment and in a schizophrenia group. However, the response was attenuated in a group with tinnitus accompanied by mild hearing impairment, similar to a healthy control group. The bias of attentional networks to self-generated sound was also observed in the subjects with tinnitus with significant hearing impairment compared to those with mild hearing impairment and healthy subjects, but it did not reach the notable disintegration found in those in the schizophrenia group. Even though the present study had significant constraints in that we did not include hearing loss subjects without tinnitus, these results might suggest that auditory deafferentation (hearing loss) may influence sensorimotor integration process using EC signals. However, the impaired sensorimotor integration in subjects with tinnitus with significant hearing impairment may have resulted from aberrant auditory signals due to sensory loss, not fundamental deficits in the reafference system, as the auditory attention network to self-generated sound is relatively well preserved in these subjects.

ISL1 is necessary for auditory neuron development and contributes toward tonotopic organization.

A cardinal feature of the auditory pathway is frequency selectivity, represented in a tonotopic map from the cochlea to the cortex. The molecular determinants of the auditory frequency map are unknown. Here, we discovered that the transcription factor ISL1 regulates the molecular and cellular features of auditory neurons, including the formation of the spiral ganglion and peripheral and central processes that shape the tonotopic representation of the auditory map. We selectively knocked out Isl1 in auditory neurons using Neurod1Cre strategies. In the absence of Isl1, spiral ganglion neurons migrate into the central cochlea and beyond, and the cochlear wiring is profoundly reduced and disrupted. The central axons of Isl1 mutants lose their topographic projections and segregation at the cochlear nucleus. Transcriptome analysis of spiral ganglion neurons shows that Isl1 regulates neurogenesis, axonogenesis, migration, neurotransmission-related machinery, and synaptic communication patterns. We show that peripheral disorganization in the cochlea affects the physiological properties of hearing in the midbrain and auditory behavior. Surprisingly, auditory processing features are preserved despite the significant hearing impairment, revealing central auditory pathway resilience and plasticity in Isl1 mutant mice. Mutant mice have a reduced acoustic startle reflex, altered prepulse inhibition, and characteristics of compensatory neural hyperactivity centrally. Our findings show that ISL1 is one of the obligatory factors required to sculpt auditory structural and functional tonotopic maps. Still, upon Isl1 deletion, the ensuing central plasticity of the auditory pathway does not suffice to overcome developmentally induced peripheral dysfunction of the cochlea.

Hearing Screening to Evaluate the Status of Newborn Hearing Impairment in the NICU of a Tertiary Hospital

Introduction: One to three per 1,000 live births suffers from significant hearing impairment. However, 2 to 4 per 100 infants who survived neonatal intensive care have some degree of sensorineural hearing loss. If hearing impairment in newborns is detected earlier, early management can prevent undesirable and often irreversible damage due to late detection.  Early detection and the treatment of hearing impairment in children are essential for the development of communication skills, social skills, emotional well-being, and positive self-esteem. Unfortunately, this disability remains undetected for many newborns until it is too late to prevent undesirable and often irreversible damage. Unfortunately, not many studies were done on this topic in Bangladesh. The magnitude of the burden of hearing impairment in the study place might be identified by this study.  The objective of the study: Hearing screening was done to see the status of hearing impairment in newborns admitted to NICU.
 Methodology: A prospective observational study was conducted in the department of neonatology, BSMMU. Newborn admitted to the NICU during the study period was the study population. The newborn who met the inclusion criteria was screened with TEOAE close to discharge from the NICU or before one month of age. A second screen was done with TEOAE again after one month of 1st screen but prior to 3 months of postnatal age if referred in 1st screen. Diagnostic ABR was done prior to 3 months of the postnatal age if referred in both the 1st and 2nd screen.
 Results: 426 valid recordings from 493 newborns admitted to the NICU enrolled consecutively constitute the basis of this study. Fourteen newborns were found to have hearing impairment among 426 newborns (3.3%). 2 newborns had unilateral hearing loss, and their hearing losses were moderate in nature. The other 12 newborns in their 24 ears had different grades of hearing loss. It was mild hearing loss in 3 ears, moderate in 9 ears, severe in 8 ears, and profound in 4 ears.
 Conclusion: Hearing screening showed that 3.3% of newborns in the NICU have a hearing impairment. It is still an underestimation considering the number of newborns who were lost to follow-up.
 TAJ 2022; 35: No-1: 77-82

MEDB-53. Incidence of Hearing impairment in childhood Medulloblastoma Survivors treated in King Fahad Medical City KFMC Saudi Arabia

Medulloblastoma MB is the most common childhood CNS tumor treated with intensive multimodalities therapy Surgery, Radiation and Cisplatin chemotherapy which causing significant Hearing impairment (HI) with profound impact on child’s quality of life. METHOD: Retrospective study evaluating risk factors & (HI) incidence in childhood MB survivors treated in KFMC between 2010 and 2020. (HI) was graded using the National Cancer Institute (NCI) Grades (1-4) ALL patients received 6 weeks of Risk adapted CSI radiotherapy concurrent with daily oral Etoposide. patients were treated with 2 different Maintenance chemotherapy German HIT-MED MB protocol 8 Maintenance cycles (Cisplatin 70 mg/m² x 1d /lomustine/VCR) Cumulative dose of Cisplatin 560 mg/m2 KFMC MB SAPHOS protocol 6 Maintenance cycle alternating A&B. cycle A: Cisplatin 90 mg/m² x 1d & 3 weeks of daily oral Etoposide. cycle B: Cyclophosphamide x 2 d & Vincristine Cumulative dose of Cisplatin 270 mg/m2. RESULTS: At Median follow-up of 5 years total of 78 MB survivors, male predominance 66.7% Median age at diagnosis 82 months post end of therapy 28.2% maintain normal hearing while 71.8% had hearing decline compared with baseline audiology Median time of onset of hearing decline was 7 months after start of radiation therapy Significant (HI) (NCI grade 3/4) in 26.9% of patients, and 23.1% required hearing aid use NO statistically difference in incidence of significant (HI) in patients treated with HIT-MED protocol (26.7%) & patients treated with KFMC MB-SAPHOS protocol (27.1%) OR those treated as Average-Risk CSI radiotherapy 22.9% Vs High-Risk CSI radiotherapy (30.2%), patients age at diagnosis (< or > 5 years) does not affects HI incidence. CONCLUSIONS: significant hearing impairment incidence was not affected by Radiation doses OR cumulative Cisplatin dose. Our study will form base line for future studies to modify therapy related Toxicity and improve outcome of childhood MB in Saudi Arabia.

Dock4 is required for the maintenance of cochlear hair cells and hearing function

Auditory hair cells (HCs) are the mechanosensory receptors of the cochlea, and HC loss or malfunction can result from genetic defects. Dock4, a member of the Dock180-related protein superfamily, is a guanine nucleotide exchange factor for Rac1, and previous reports have shown that Dock4 mutations are associated with autism spectrum disorder, myelodysplastic syndromes, and tumorigenesis. Here, we found that Dock4 is highly expressed in the cochlear HCs of mice. However, the role of Dock4 in the inner ear has not yet been investigated. Taking advantage of the piggyBac transposon system, Dock4 knockdown (KD) mice were established to explore the role of Dock4 in the cochlea. Compared to wild-type controls, Dock4 KD mice showed significant hearing impairment from postnatal day 60. Dock4 KD mice showed hair bundle deficits and increased oxidative stress, which eventually led to HC apoptosis, late-onset HC loss, and progressive hearing loss. Furthermore, molecular mechanism studies showed that Rac1/β-catenin signaling was significantly downregulated in Dock4 KD cochleae and that this was the cause for the disorganized stereocilia and increased oxidative stress in HCs. Overall, our work demonstrates that the Dock4/Rac1/β-catenin signaling pathway plays a critical role in the maintenance of auditory HCs and hearing function.

Auditory outcome following aneurysmal subarachnoid haemorrhage

Auditory deficits are increasingly recognised following aneurysmal subarachnoid haemorrhage (aSAH) and are thought to be of central rather than peripheral origin. Central hearing impairment, also known as auditory processing disorder (APD), often coexists with cognitive deficits and it is thought that APD has both auditory and cognitive elements. The aim of this study was to assess auditory outcome following aSAH and its relationship with cognition. A retrospective case-controlled study design was employed with aSAH cases and matched controls identified from the UK Biobank. Auditory and cognitive outcomes were assessed using the digit triplet test (DTT) and a test of psychomotor reaction time, respectively. Best DTT score was compared between cases and controls using the t-test. A regression-based mediation analysis was performed to assess whether cognition mediated auditory outcome. 270 aSAH patients with auditory outcomes were identified with an average follow-up of 106 months. A matched control cohort of 1080 individuals was also identified. The aSAH cohort had significantly impaired best DTT scores compared to matched controls (p = 0.002). Cognition significantly mediated auditory outcome following aSAH, accounting for 9.8% of the hearing impairment after aSAH. In conclusion significant hearing impairment follows aSAH. The deficit is bilateral and non-progressive. There is a link with cognitive deficit, pointing to a central rather than peripheral source, in keeping with an auditory processing disorder. All aSAH patients should be asked about hearing difficulty at follow-up and when present it should be investigated with peripheral and central auditory assessments, as well as cognitive tests.

Clinical and diagnostic characteristics of cochleovestibular function in patients of active working age after exposure to stress

Topicality: Long-term and pronounced psychoemotional tension leads to negative changes in the human body. Many aspects of cochleovestibular changes caused by psychoemotional stress are not studied enough to date. Aim: to increase the diagnostic efficiency of auditory and vestibular disorders in patients of active working age after exposure to stress. Materials and methods: 95 patients of active working age with dizziness, which manifested under stress, and 10 persons of control group were studied. The following tests were performed to all patients: survey with the questionnaire "Comprehensive stress assessment", pure tone and speech audiometry, measurement with filtered speech discrimination tests, assessment of the auditory adaptation level, impedancemetry, registration of auditory brainstem responses (ABR), computed static posturography, vestibular testing. Results and discussion: All subjects were divided into three groups according to the results of the survey with the questionnaire "Comprehensive stress assessment": Group 1 included 21 patients with moderate stress, Group 2 included 35 persons with severe stress that could not be compensated and Group 3 included 39 persons under severe stress, moreover 10 of them were on the verge of exhaustion of adaptive capacities. 60 (63.2 %) patients had normal hearing. 24 (25.2 %) subjects had statistically significant (P &lt;0.05) hearing impairment in the high frequency zone compared with the control group, a statistically significant difference in hearing impairment was detected in the entire frequency range in 11 (11.6 %) persons. Central auditory processing disorders were detected in more than half of patients (according to various tests – from 29 (30.5 %) to 49 (51.6 %) persons). Central vestibular syndrome of varying severity was diagnosed in all 95 patients. The most pronounced disorders of balance according to posturography have been reported in patients with severe stress with vision deprivation in the position with closed eyes. Conclusions: An integrated approach allowed to identify and select, besides traditional research methods, supplementary diagnostic measures for optimal assessment of cochleovestibular changes in patients of active working age after exposure to stress, to detect cochleovestibular disorders and differential topical diagnostics of disorders of the central or peripheral portions of the auditory and vestibular analyzers. These included psychological testing, a test battery to determine central auditory processing disorders – hearing adaptation with load, filtered speech discrimination tests, registration of ABR, registration of postural balance using the Wii Balance Board platform, vestibular testing.

ДИДАКТИЧЕСКИЙ ПОТЕНЦИАЛ МУЛЬТИПЛИКАЦИИ В РАЗВИТИИ РЕЧИ СТАРШИХ ДОШКОЛЬНИКОВ С БИСЕНСОРНЫМИ НАРУШЕНИЯМИ

Statement of the problem. Modern researchers emphasize the need for practical use of new tools, including the use of information and communication tools, learning and development of children with disabilities. One of the growing groups of children with disabilities is a group of preschoolers with simultaneous hearing and visual impairments. With regard to this group of children, the problem field for research is wide, and scientific developments are few. Therefore, the problem of finding means of comprehensive development of preschool children with bisensory impairments, and, in particular, their speech development, remains quite relevant in visual impairment pedagogy. One of such means, according to the authors of the article, is cartoon animation. The purpose of the article is to disclose the didactic potential of cartoon animation as a pedagogical tool in the development of speech among preschool children with significant hearing impairment and simultaneous visual impairment in the degree of visually impaired. Methodology (materials and methods) The research methodology is based on the fundamental scientific work of S.A. Zykov, revealing the essence of communicative-activity system and its leading role in the speech development of children with hearing impairment; it is also based on the analysis of foreign and Russian scientific works, revealing the content of innovative approaches in teaching children with bisensory impairment. Research results. The article reveals the didactic potential of cartoon animation as a means of speech development among children with significant hearing impairment corrected by hearing aids or cochlear implants and simultaneous visual impairment in the degree of amblyopia. It is shown that the essential content of the process of creating cartoons in the joint activity of children and adults, as well as the use of ready-made cartoons, plays an essential role in the complex process of speech development, namely, in the development of grammatical structure of speech, coherent speech, and enrichment of the vocabulary. We have developed an algorithm for the joint activities of an adult and a child with simultaneous hearing and vision impairment in the creation of cartoon films aimed at the speech development of this group of children. Conclusion. Cartoon animation, being a modern information and communication tool, has a high potential for application in defectology. The process of creating cartoons in the joint activity of preschool children with bisensory impairments and adults, as well as the use of ready-made cartoons they have created, is potentially one of the effective techniques of the communicative-activational system used in deaf-blind pedagogy and typhlo-surdopedagogy. The process of creating cartoons can be used as a means of developing all components of speech in preschool children with significant hearing impairment with correction by hearing aids or cochlear implants and simultaneous visual impairment of low vision.