Auditory Pathway Maturation in Full-term Small for Gestational Age Children: A Systematic Review with Meta-analysis.

Introduction Factors of intrauterine growth restriction have been responsible for the births of full-term babies small for their gestational age (SGA). Scientific evidence points that this restriction can cause changes in the neural maturation process. Objectives To analyze the absolute latencies and interpeak intervals of brainstem auditory evoked potential waves in full-term and SGA children to investigate whether there are changes of neural maturation in this population. Data Synthesis The search for articles that reported the assessment of brainstem auditory evoked potential in SGA newborns compared with a control, appropriate for their gestational age, both born full-term, for the entire period available in the database research until October 31, 2021 was performed based on the MEDLINE/PubMed Central and on the Latin America and the Caribbean Health Sciences Literature and Virtual Health Library electronic databases. A total of 311 studies were found in the database research. Out of this total, 10 studies were included in the review, 5 of which were eligible for the meta-analysis, involving a total of 473 participants of both genders, with 193 participants belonging to the study group and 280 to the control group. Differences between the groups were only observed in the absolute latency of wave V (95% confidence interval [CI]: 0.02-0.15; p < 0.01). Conclusion The SGA condition is responsible for the appearance of brainstem neural conduction dysfunction measured by the brainstem auditory evoked potentials, probably by the maturation process of the auditory pathway of this population.

Subclinical neural hearing alterations in school children with type 1 diabetes mellitus.

BACKGROUND AND OBJECTIVES: Evidence has shown a cause-and-effect relationship between type 1 diabetes mellitus and auditory and cognitive dysfunctions. This study aimed to investigate the effect of type 1 diabetes mellitus (T1DM) on central auditory and cognitive functions in school-age children and adolescents. METHODS: The study sample consisted of 101 children and adolescents, 50 with T1DM, of both sexes, aged between 7 and 18 years. All participants were selected for a structured interview on hearing, behavioral, and cognitive health and assessment of brainstem auditory evoked potentials (BAEP) and event-related potentials (P300). RESULTS: Significant differences were observed in memory (p=0.002) and attention (p=0.021) complaints between participants with and without T1DM. In the BAEP responses, there were differences between wave III latencies in the right (p=0.017) and left (p=0.019) ears and in wave V latencies in the left ear (p=0.001) between the evaluated groups. In addition, there was an association between BAEP findings and metabolic control in the T1DM group in the left ear in waves III (p=0.006) and V (p=0.005) and in the right ear in wave V (p=0.026). No differences were observed in the latencies of P300 between the evaluated groups. CONCLUSION: This study demonstrated the existence of a subclinical finding in the central auditory pathway, offering an increased risk for retrocollear alterations, which may be a consequence of poor metabolic control.

Auditory Pathway Maturation in Full-term Small for Gestational Age Children: A Systematic Review with Meta-analysis

Abstract Introduction Factors of intrauterine growth restriction have been responsible for the births of full-term babies small for their gestational age (SCA). Scientific evidence points that this restriction can cause changes in the neural maturation process. Objectives To analyze the absolute latencies and interpeak intervals of brainstem auditory evoked potential waves in full-term and SCA children to investigate whether there are changes of neural maturation in this population. Data Synthesis The search for articles that reported the assessment of brainstem auditory evoked potential in SCA newborns compared with a control, appropriate for their gestational age, both born full-term, for the entire period available in the database research until October31, 2021 was performed based on the MEDLINE/PubMed Central and on the Latin America and the Caribbean Health Sciences Literature and Virtual Health Library electronic databases. A total of 311 studies were found in the database research. Out of this total, 10 studies were included in the review, 5 of which were eligible for the meta-analysis, involving a total of 473 participants of both genders, with 193 participants belonging to the study group and 280 to the control group. Differences between the groups were only observed in the absolute latency of wave V (95% confidence interval [CI]: 0.02-0.15; p<0.01). Conclusion The SCA condition is responsible for the appearance of brainstem neural conduction dysfunction measured by the brainstem auditory evoked potentials, probably by the maturation process of the auditory pathway of this population.

Perda auditiva na hemoglobinopatia SC (HbSC): relato de caso / Hearing loss in SC hemoglobinopathy (HbSC): case report

Introdução: Doença falciforme (DF) engloba um conjunto de hemoglobinopatias marcadas pela hemoglobina (Hb) anormal S (HbS). A HbS possui um formato de foice e aumento de rigidez, culminando em hemólise. Além disso, dificulta a passagem pela microcirculação sanguínea, causando vaso-oclusão e lesão isquêmica em diversos órgãos e tecidos. Na orelha interna, tem sido descrita como os responsável por danos auditivos. Objetivo: apresentar um relato de caso de paciente do sexo feminino com doença falciforme, acometida de perda auditiva sensorioneural (PASN) bilateral assimétrica. Relato do caso: paciente do sexo feminino, destra, 45 anos, compareceu para avaliação, queixando se de diminuição da audição e zumbido na orelha esquerda. Foi submetida à avaliação audiológica, constituída por audiometria tonal limiar, logoaudiometria, imitanciometria, emissões otoacústicas por produto de distorção (EOAPD) e potencial evocado auditivo do tronco encefálico (PEATE). Resultados: constatou-se: perda auditiva sensorioneural bilateral de grau leve na orelha direita e severo na orelha esquerda; presença dos reflexos estapedianos contralaterais na orelha direita e ausência na orelha esquerda; curvas timpanométricas tipo A; ausência de emissões otoacústicas bilateralmente; e os potenciais auditivos evocados do tronco encefálico dentro dos padrões de normalidade. Discussão: diversos mecanismos estão envolvidos na relação DF e PASN, como a falta de oxigenação e infarto do órgão de Corti, hemorragia labiríntica e labirintite ossificante, bem como uma associação entre o nível de viscosidade sanguínea, disfunção endotelial e hipertensão sistêmica. E ainda deve ser considerada a questão de dominância hemisférica na assimetria da perda. Conclusão: os conhecimentos sobre as características dos danos auditivos na HbSC ainda não são conclusivos e merecem mais investigações. A implementação de avaliações periódicas da função auditiva tem contribuído para prevenir a progressão dos danos e auxiliado no tratamento precoce.

Introduction: Sickle cell disease (SCD) comprises a set of hemoglobinopathies marked by abnormal hemoglobin (Hb) S (HbS). HbS has a sickle shape and increased stiffness culminating in hemolysis, in addition to making it difficult to pass through the blood microcirculation, causing vessel-occlusion and ischemic damage in various organs and tissues. In the inner ear, they have been described as responsible for hearing damage. Objective: describing a case report of a female patient with sickle cell disease affected by asymmetric bilateral sensorineural hearing loss (SNHL). Case report: a 45-year-old female patient, right-handed, came for evaluation, complaining of decreased hearing and tinnitus in her left ear. She underwent audiological evaluation consisting of pure tone audiometry, logoaudiometry, immittance testing, distortion product otoacoustic emissions (DPOAE) and brainstem auditory evoked potential (BAEP). Results: bilateral mild sensorineural hearing loss in the right ear and severe in the left ear, presence of contralateral stapedial reflexes in the right ear and absence in the left ear, type A tympanometric curves, absence of bilateral otoacoustic emissions and the brainstem auditory evoked potentials within the normality patterns. Discussion: Several mechanisms are involved in the SCD and SNHL relationship, such as the lack of oxygen and infarction of the Organ of Corti, labyrinthine hemorrhage and ossifying labyrinthitis, as well as an association between the level of blood viscosity, endothelial dysfunction and systemic hypertension. And the question of hemispheric dominance in the loss asymmetry must still be considered. Conclusion: knowledge about the characteristics of hearing damage in HbSC is not yet conclusive and deserves further investigation. Implementation of periodic auditory function assessments has helped to prevent the progression of damage and has helped in early treatment.

Effects of type 1 diabetes mellitus on efferent auditory system in children and adolescents.

AIM: To investigate whether type 1 diabetes mellitus (T1DM) could affect the efferent auditory system by analyzing the relationship between the activation of the medial olivocochlear reflex with disease duration, metabolic control and age at time of diagnosis. METHOD: A total of 101 children and adolescents were evaluated. They were divided into two groups: 50 with T1DM and 51 without the disease. The participants answered a structured questionnaire containing questions about auditory complaints and were evaluated for tonal audiometry, tympanometry, acoustic reflex, otoacoustic emission by distortion product to evaluate the inhibitory effect of medial olivocochlear reflex (MOC). RESULTS: The participants with T1DM presented changed AR (increased or absent) at all the frequencies in both ears (p < 0.05) when compared with the group without the disease. No differences were found between the DPOAE amplitudes of the individuals with and without T1DM, in both ears at all the frequencies. There were significant differences in the activation of the MOC reflex between the groups with and without T1DM, the participants with T1DM presented the absence of the inhibitory effect of the DPOAE in the right and left ears, in the frequencies of 4000 Hz (p = 0.035/0.002respectively) and 6000 Hz (p = 0.033/0.031 respectively) and 8000 Hz (p = 0.007/0.001 respectively) when compared to the healthy group. Significant differences were also observed between the groups with and without T1DM (p < 0.05) for self-reported complaints of tinitus, difficulties with the perception of speech when there was noise and distraction with noise. No association was found between the hearing complaints and the audiological measurements obtained and disease time, metabolic control and age at the time of diagnosis. CONCLUSION: The findings suggest the presence of early auditory dysfunction of the efferent pathway in patients with T1DM.

Dysfunction of the auditory system in sickle cell anaemia: a systematic review with meta-analysis.

OBJECTIVES: To describe the occurrence of both peripheral and central auditory system dysfunction in sickle cell anaemia (SCA) patients and discuss the different mechanisms hypothesised to be responsible for these alterations. METHODS: An electronic search was conducted using PubMed Central® (MEDLINE), LILACS® and Scopus® databases. This systematic review was performed in accordance with the PRISMA statement. Original observational studies that utilised audiological tests for auditory system evaluations in SCA were included. RESULTS: A total of 183 records were found in the databases searched. Twenty-one of these studies met the inclusion criteria. Pooled prevalence of sensorineural hearing loss (SNHL) was 20.5% (CI: 10.3-33%). Retrocochlear involvement was detected with the auditory brainstem response, which assesses integrity of the cochlea, 8th cranial nerve and brainstem structures. In addition, the increase in otoacoustic emission amplitudes in SCA patients indicates changes in cochlear micromechanics and precedes the expression of a detectable cochlear pathology. CONCLUSION: The prevalence of the SNHL is higher than in the general population. Dysfunction of the auditory system may be present in SCA patients, with the most probable mechanism being the presence of circulatory disturbances resulting from the chronic inflammatory state of the disease.

DYSFONCTIONNEMENT DU SYSTÈME AUDITIF DANS L'ANÉMIE FALCIFORME: REVUE SYSTÉMATIQUE ET MÉTA-ANALYSE: OBJECTIFS: Décrire l'apparition de dysfonctionnements du système auditif périphérique et central chez les patients atteints d'anémie falciforme (AF) et discuter des différents mécanismes supposés responsables de ces altérations. MÉTHODES: Une recherche électronique a été effectuée dans les bases de données PubMed Central® (MEDLINE), LILACS® et Scopus® . Cette revue systématique a été réalisée conformément au PRISMA Statement. Des études observationnelles originales utilisant des tests audiologiques pour évaluer le système auditif dans l'AF ont été incluses. RÉSULTATS: Un total de 183 enregistrements ont été trouvés dans les bases de données consultées. Vingt et une de ces études répondaient aux critères d'inclusion. La prévalence poolée de la perte auditive neurosensorielle (SNHL) était de 20,5% (IC: 10,3% à 33%). L'atteinte rétrocochléaire a été détectée avec la réponse du tronc cérébral auditif, qui évalue l'intégrité de la cochlée, du huitième nerf crânien et de la structure du tronc cérébral. De plus, l'augmentation des amplitudes des émissions otoacoustiques chez les patients atteints de l'AF indique des modifications de la micromécanique cochléaire et précède l'expression d'une pathologie cochléaire détectable. CONCLUSION: La prévalence de la SNHL est plus élevée que dans la population générale. Un dysfonctionnement du système auditif peut être présent chez les patients AF, le mécanisme le plus probable étant la présence de troubles circulatoires résultant de l'état inflammatoire chronique de la maladie.

Hidden hearing loss in children and adolescents with sickle cell anemia.

OBJECTIVE: To evaluate the auditory system for hidden hearing loss (HHL) and its association with clinical variables and endothelial dysfunction (ED) in children and adolescents with sickle cell anemia (SCA). METHODS: Participants included 37 patients with stable SCA and 44 healthy controls (HC group) (aged 6-18 years) with hearing thresholds ≤ 20 dB (dB) were evaluated for pure tone audiometry, tympanometry, acoustic reflex, otoacoustic emission, and auditory evoked potentials. Laboratory analysis of the lipid profile, and C-reactive protein levels and endothelial function using ultrasonographic imaging of the brachial artery to assess flow-mediated dilation were performed. RESULTS: The SCA group presented with a higher rate of increased contralateral acoustic reflex thresholds, compared to those in the HC group at all frequencies and in both ears (p < 0.05). There were significant differences in the brainstem auditory evoked potentials between the SCA and HC groups. In the SCA group, the waves III and V latencies were increased (p = 0.006 and 0.004 respectively), and the I-III and I-V interpeak intervals were longer (p = 0.015 and 0.018 respectively) than those in the HC group. There was no association between the audiological measures and clinical and metabolic variables and sickle cell anemia complications including endothelial function and therapy. CONCLUSION: In conclusion, our findings suggest that damage in the auditory system in SCA patients can be present involving retrocochlear structures, causing functional deficits without deterioration of auditory sensitivity.

Association between endothelial dysfunction and otoneurological symptoms in children with sickle cell disease.

OBJECTIVE: To evaluate the association between endothelial dysfunction and otoneurological symptoms and vaso-occlusive phenomena in children with sickle cell disease (SCD). METHODS: Cross-sectional study with 54 children, aged between 6 and19 years of age, of whom 28 had genotype SS and 26 apparently healthy (AA genotype) whose parents or guardians, or the children themselves, filled out a questionnaire designed to assess their otoneurological symptoms. All the individuals were submitted assessment of endothelial function by flow-mediated dilation (FMD) percentage with reactive hyperemia of brachial artery Doppler. RESULTS: Otoneurological symptoms (tinnitus and/or vertigo) predominated in the SCD group (46.4 vs. 15.4%; p = 0.006). A negative correlation was observed between FMD percentage and time of evolution of vertigo SCD (r = -0.432; p = 0.022) and the linear regression analysis demonstrated that for every reduction in FMD percentage there was an increase in time of evolution of vertigo of 1.79 months (ß = -1.79; p = 0.022). The positive correlation between episodes of painful crisis and time of evolution of vertigo (r = 0.3; p = 0.04). DISCUSSION: The presence of vascular endothelial damage in the labyrinthine artery in patients with SCD is capable of compromising the semicircular canals, shown by clinical expression of otoneurological symptoms, such as vertigo. In the present study, an association was observed between endothelial dysfunction with otoneurological symptoms and otoneurological symptoms and vaso-occlusive phenomena in SCD.