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Braz. j. med. biol. res ; 54(7): e10579, 2021. tab, graf
Article in English | LILACS | ID: biblio-1249313


NOTCH pathway proteins, including the transcriptional factor HES1, play crucial roles in the development of the inner ear by means of the lateral inhibition mechanism, in which supporting cells have their phenotype preserved while they are prevented from becoming hair cells. Genetic manipulation of this pathway has been demonstrated to increase hair cell number. The present study aimed to investigate gene expression effects in hair cells and supporting cells after Hes1-shRNA lentivirus transduction in organotypic cultures of the organ of Corti from postnatal-day-3 mice. Forty-eight hours after in vitro knockdown, Hes1 gene expression was reduced at both mRNA and protein levels. Myo7a (hair cell marker) and Sox2 (progenitor cell marker) mRNA levels also significantly increased. The modulation of gene expression in the organ of Corti upon Hes1 knockdown is consistent with cell phenotypes related to lateral inhibition mechanism interference in the inner ear. The lentivirus-based expression of Hes1-shRNA is a valuable strategy for genetic interference in the organ of Corti and for future evaluation of its efficacy in protocols aiming at the regeneration of hair cells in vivo.

Animals , Rats , Cochlea , Basic Helix-Loop-Helix Transcription Factors/genetics , Organ of Corti , Cell Differentiation , Receptors, Notch , Transcription Factor HES-1/genetics , Hair Cells, Auditory
Acta otorrinolaringol. cir. cabeza cuello ; 49(3): 184-188, 2021. ilus, tab
Article in Spanish | LILACS, COLNAL | ID: biblio-1292707


Introducción: el tinnitus tiene efectos deletéreos sobre la calidad de vida de un paciente. Cuando la lesión está a nivel coclear, se puede usar acondicionamiento acústico para su tratamiento. Objetivo: determinar el cambio en la percepción del tinnitus antes y después de la intervención terapéutica. Metodología: se planteó un estudio de serie de casos. Pacientes con tinnitus no pulsátil de moderado a catastrófico tratados con estimulador REVE 134™. Se incluyeron pacientes que no mejoraron luego de 3 meses con tratamiento médico. Se les practicó microaudiometría (67 frecuencias) para definir la región coclear afectada. Se excluyeron pacientes con umbrales audiométricos > 60 dB, aquellos con lesiones retrococleares y quienes no desearon participar. Las variables de desenlace fueron Tinnitus Handicap Inventory (THI), escala visual análoga (EVA) y Tinnitus Reaction Questionnaire (TQR), que se midieron pretratamiento y a los 3 y 6 meses postratamiento. Resultados: se incluyeron 11 pacientes (hombres = 5, mujeres = 6). En 5 casos el tinnitus fue bilateral y en 6, unilateral. Los valores pretratamiento fueron THI = 61,4 ± 27,4, EVA = 6,9 ± 2,7 y TQR = 43,2 ± 31,9 (Kolmogorov-Smirnov, p > 0,05). Hubo mejoría estadísticamente significativa con el tratamiento, THI (3 meses = 30,6 ± 21,1; 6 meses = 19 ± 19,2), EVA (3 meses = 5,6 ± 2,3; 6 meses = 3,5 ± 2,0), TQR (3 meses = 25,6 ± 20,0; 6 meses = 14,3 ± 19,9); ANOVA de medidas repetidas (p = 0,007, p = 0,027, p = 0,037; respectivamente). Conclusión: el tratamiento con REVE 134™ fue efectivo en pacientes con tinnitus no pulsátil de moderado a catastrófico.

Introduction: tinnitus can affect the quality of life of a patient. Acoustic stimulation can be used as treatment when the cause of tinnitus is located in the cochlea. Objective: To determine changes in tinnitus perception before and after therapeutic intervention. Methodology: We performed a case series study. Patients with nonpulsatile tinnitus, with no improvement with medical therapy, and moderate to catastrophic grade were treated with the REVE 134™ system. A microaudiometry (67 frequencies) was performed to determine the cochlear regions affected. Patients with auditory thresholds >60 dB, retrocochlear pathologies and who did not want to participate in the study were excluded. The variables studied were Tinnitus Handicap Inventory (THI), Visual Analog Scale (VAS) and Tinnitus Reaction Questionnaire (TQR), that were measured before, three and six months after treatment. Results: 11 patients (male: 5, women: 6) were included. In 5 of them, tinnitus was bilateral and in 6, unilateral. Pretreatment values were: THI = 61.4 ± 27.4, VAS = 6.9 ± 2.7 and TQR = 43.2 ± 31.9 (Kolmogorov-Smirnov, p > 0.05). We found improvement in tinnitus perception with the therapy, and this values had statistical significance (THI: 3rd month = 30.6 ± 21.1; 6th month = 19 ± 19.2), VAS (3rd month = 5.6 ± 2.3; 6th month = 3.5 ± 2.0), TQR (3rd month = 25.6 ± 20.0; 6th month =14.3 ± 19.9); repetitive measures of ANOVA (p = 0.007, p = 0.027, p = 0.037; respectively). Conclusion: Treatment with REVE 134™ was effective in patients with moderate to catastrophic tinnitus.

Humans , Tinnitus , Cochlea , Hearing Loss
Article in Chinese | WPRIM | ID: wpr-922072


For cochlear implant training and robotic cochlear implant experiments, the design method of scalable scala tympani model was proposed. The mathematical model of the cochlea was used as the central curve of scala tympani channel. Referring to the clinical anatomy data, the contour of the scala tympani cross-section was approximated as an ellipse. The profile was placed along the central curve, and the angle was adjusted to determine the position and orientation of the profile in three dimensions such that the central curve passes through its center. The data was imported into Matlab to generate a three-dimensional mathematical model of scala tympani, which can be expanded by setting different scale factors. The virtual scala tympani model was generated in SolidWorks, and the 2:1 fully transparent scala tympani model were fabricated by 3D printing to replace the specimen for experiment.

Cochlea/surgery , Cochlear Implantation , Cochlear Implants , Robotics , Scala Tympani/surgery
Braz. j. otorhinolaryngol. (Impr.) ; 86(2): 222-227, March-Apr. 2020. graf
Article in English | LILACS | ID: biblio-1132576


Abstract Introduction: The use of electron microscopy in the study of the inner ear has allowed us to observe minute details of the hair cells, especially in ototoxicity studies; however, the preparation of this material is a difficult and delicate task. In an attempt to simplify the handling of these materials, two agents, toluidine blue and ethylenediamine tetra-acetic acid were tested, in addition to the elimination of osmium tetroxide during the preparation of albino guinea pig cochleae. We also tested the applicability of these methodologies in an ototoxicity protocol. Objective: To verify the quality of the images obtained with and without the use of ethylenediamine tetra-acetic acid, toluidine blue and osmium tetroxide in the preparation of cochleae of albino guinea pigs for the scanning electron microscopy. Methods: Three groups of cochleae were used. In Group 1, 10 cochleae were prepared with the usual methodology, dissecting the optical capsule without decalcification and using osmium tetroxide as a post-fixative agent. In Group 2, we prepared 10 cochleae decalcified with ethylenediamine tetra-acetic acid, injecting toluidine blue in the endolymphatic space to facilitate the identification of the organ of Corti. In Group 3, we used 4 cochleae of guinea pigs that received 3 doses of cisplatin (7.5 mg/kg, D1-D5-D6), two prepared according to the methodology used in Group 1 and two with that used in Group 2. Scanning electron microscopy images were obtained from the organ of Corti region of the basal turn of each cochlea. Results: The organ of Corti was more easily identified with the use of toluidine blue. The dissection of the cochlea was more accurate in the decalcified cochleae. The quality of the images and the preservation of the organ of Corti obtained with the two methodologies were similar. Conclusion: The proposed modifications resulted in images of similar quality as those observed using the traditional methodology.

Resumo Introdução: O emprego da microscopia eletrônica no estudo da orelha interna permitiu observar detalhes minuciosos das células ciliadas especialmente em estudos de ototoxicidade. Entretanto, o preparo desse material é trabalhoso e delicado. Para simplificar a manipulação desses materiais, testou-se o uso de dois agentes, azul de toluidina e ácido etilenodiamino tetra-acético, além da retirada do tetróxido de ósmio na preparação de cócleas de cobaias albinas. Testamos também a aplicabilidade dessas metodologias em um protocolo de ototoxicidade. Objetivo: Verificar a qualidade das imagens obtidas com e sem o uso de ácido etilenodiamino tetra-acético, azul de toluidina e tetróxido de ósmio na preparação de cócleas de cobaias albinas para a microscopia eletrônica de varredura. Método: Foram utilizados três grupos de cócleas. No Grupo 1 preparou-se 10 cócleas com a metodologia usual, dissecando a cápsula ótica sem descalcificac¸ão e utilizando tetróxido de ósmio como pós-fixador. No Grupo 2 preparamos 10 cócleas descalcificadas com ácido etilenodiamino tetra-acético, injetando azul de toluidina no espac¸o endolinfático para facilitar a identificação do órgão de Corti. No Grupo 3 utilizamos 4 cócleas de cobaias que receberam 3 doses de cisplatina (7,5 mg/kg, D1-D5-D6), duas preparadas com a metodologia do Grupo 1 e duas com a do Grupo 2. Foram obtidas imagens da microscopia eletrônica de varredura da região do órgão de Corti do giro basal de cada cóclea. Resultados: O órgão de Corti foi mais facilmente identificado com o azul de touidina. A dissecção da cóclea foi mais precisa nas cócleas descalcificadas A qualidade das imagens e a preservac¸ão do órgão de Corti obtidas com as duas metodologias foi similar. Conclusão: As modificações propostas resultaram em imagens de qualidade similar as observadas com o uso da metodologia tradicional.

Animals , Female , Cisplatin/toxicity , Cochlea/drug effects , Cochlea/ultrastructure , Organ of Corti/drug effects , Organ of Corti/ultrastructure , Osmium Tetroxide/administration & dosage , Tolonium Chloride/administration & dosage , Microscopy, Electron, Scanning , Edetic Acid/administration & dosage , Guinea Pigs , Hair Cells, Auditory/drug effects , Hair Cells, Auditory/ultrastructure
Int. arch. otorhinolaryngol. (Impr.) ; 24(1): 47-52, Jan.-Mar. 2020. graf
Article in English | LILACS | ID: biblio-1090559


Abstract Introduction Cisplatin damages the auditory system and is related to the generation of free radicals. Glutathione peroxidase is an endogenous free radicals remover. Objective To investigate the mechanisms involved in otoprotection by N-acetylcys- teine through the expression of glutathione peroxidase in outer hair cells from rats treated with cisplatin. Methods Male Wistar rats were intraperitoneally injected with cisplatin (8 mg/Kg) and/or received oral administration by gavage of N-acetylcysteine (300 mg/Kg) for 3 consecutive days. On the 4th day, the animals were euthanized and beheaded. The tympanic bullae were removed and prepared for scanning electron microscopy and Results Among the groups exposed to ototoxic doses of cisplatin, there was an increase in glutathione peroxidase immunostaining in two groups, the one exposed to cisplatin alone, and the group exposed to both cisplatin and N-acetylcysteine. Conclusion The expression of glutathione peroxidase in the outer hair cells of rats exposed to cisplatin showed the synthesis of this enzyme under cellular toxicity conditions.

Animals , Male , Acetylcysteine/therapeutic use , Free Radical Scavengers/therapeutic use , Cisplatin/toxicity , Oxidative Stress/drug effects , Antineoplastic Agents/toxicity , Acetylcysteine/metabolism , Acetylcysteine/pharmacology , Microscopy, Electron, Scanning , Evoked Potentials, Auditory, Brain Stem , Free Radical Scavengers/metabolism , Free Radical Scavengers/pharmacology , Fluorescent Antibody Technique , Cisplatin/therapeutic use , Rats, Wistar , Cochlea/anatomy & histology , Cochlea/drug effects , Free Radicals , Glutathione Peroxidase/metabolism , Hearing Loss, Sensorineural/prevention & control
Braz. j. otorhinolaryngol. (Impr.) ; 86(1): 30-37, Jan.-Feb. 2020. tab, graf
Article in English | LILACS | ID: biblio-1089360


Abstract Introduction Ototoxicity is a health problem appearing after powerful treatments in serious health conditions. It is sometimes inevitable when treatment of the serious disease is required. Cisplatin is an antineoplastic agent which was investigated previously to reveal increased nitrogen and reactive oxygen radicals that damages hair cells, resulting in ototoxicity. N-acetylcysteine, previously shown to decrease ototoxicity caused by different agents, is known to be a powerful in vitro antioxidant. Probably N-acetylcysteine, in addition to its antioxidant effect, blocks a cascade where reactive oxygen species result in apoptosis in the cochlea. Objectives The possible preventive effect of N-acetylcysteine in cisplatin ototoxicity was studied with auditory brain stem responses, otoacoustic emissions, and histopathological investigation of the cochlea in a scanning electron microscopy. Methods This study was conducted on 21 Wistar Albino rats in four groups. 1 mL/kg/day three times in total intraperitoneal (i.p.) Saline (n = 5), 500 mg/kg/day i.p. three times in total N-acetylcysteine (n = 5), i.p. 15 mg/kg cisplatin alone (single dose) (n = 5) and i.p. 15 mg/kg cisplatin plus 500 mg/kg/day N-acetylcysteine (n = 6) were administered. The rats were anesthetized to study the hearing tests before and after the experiment. The rats were sacrificed to investigate the cochleas by scanning electron microscopy. Results Auditory brain stem responses and otoacoustic emissions values were attenuated in the cisplatin group. The group that received N-acetylcysteine in addition to cisplatin had better auditory brain stem responses thresholds and otoacoustic emissions. The samples obtained from the cisplatin group showed surface irregularities, degeneration areas, and total or partial severe stereocilia losses. The changes were milder in the cisplatin + N-acetylcysteine group. Conclusion Cisplatin ototoxicity can be detected by auditory brain stem responses and otoacoustic emissions testing in rats. N-acetylcysteine may protect the cochlear cells from histopathological changes. We concluded that N-acetylcysteine given 4 h after cisplatin injection has a potential otoprotective effect against cisplatin ototoxicity. which suggests it could be used in clinical trials.

Resumo Introdução A ototoxicidade é um problema que pode ocorrer após certos tipos de tratamentos para condições graves de saúde. Às vezes é inevitável quando o tratamento da doença é necessário. A cisplatina é um agente antineoplásico cujo uso em pesquisas anteriores demonstrou aumentar os radicais livres de nitrogênio e espécies reativas de oxigênio que danificam as células ciliadas e resultam em ototoxicidade. Por outro lado, a N-acetilcisteína, que já demonstrou diminuir a ototoxicidade causada por diferentes agentes, é conhecida por ser um potente antioxidante in vitro. Provavelmente a N-acetilcisteína, além de seu efeito antioxidante, bloqueia uma cascata onde espécies reativas de oxigênio resultam em apoptose na cóclea. Objetivos Estudar o possível efeito preventivo da N-acetilcisteína na ototoxicidade por cisplatina por meio de potencial evocado auditivo de tronco encefálico, emissões otoacústicas e investigação histopatológica da cóclea por microscopia eletrônica de varredura. Método Este estudo foi realizado em 21 ratos albinos Wistar, separados em quatro grupos. Foram administrados: 1 mL/kg/dia intraperitoneal (i.p.) de solução salina (n = 5), três vezes no total; 500 mg/kg/dia i.p. de N-acetilcisteína (n = 5), três vezes no total; 15 mg/kg i.p. (dose única) somente de cisplatina (n = 5) e 15 mg/kg i.p. de cisplatina e 500 mg/kg/dia i.p. de N-acetilcisteína (n = 6). Os ratos foram anestesiados para estudo dos testes auditivos antes e depois do experimento. Os ratos foram sacrificados para investigação da cóclea por microscopia eletrônica de varredura. Resultados Os potenciais evocados auditivos de tronco encefálico e os valores das emissões otoacústicas estavam atenuados no grupo cisplatina. O grupo que recebeu N-acetilcisteína além da cisplatina apresentou melhores limiares de respostas auditivas do tronco encefálico e emissões otoacústicas. As amostras obtidas do grupo cisplatina apresentaram irregularidades de superfície, áreas de degeneração, com perdas graves totais ou parciais de estereocílios. As alterações foram mais leves no grupo cisplatina + N-acetilcisteína. Conclusão A ototoxicidade por cisplatina pode ser detectada por meio de potenciais evocados auditivos de tronco encefálico e pelo teste de emissões otoacústicas em ratos. A N-acetilcisteína pode proteger as células cocleares contra alterações histopatológicas. Concluímos que a N-acetilcisteína administrada 4 horas após a injeção de cisplatina tem potencial efeito otoprotetor contra a ototoxicidade por cisplatina e pode ser utilizada em ensaios clínicos.

Animals , Male , Acetylcysteine/administration & dosage , Cisplatin/adverse effects , Protective Agents/administration & dosage , Ototoxicity/etiology , Antineoplastic Agents/adverse effects , Antioxidants/administration & dosage , Acetylcysteine/pharmacology , Microscopy, Electron, Scanning , Evoked Potentials, Auditory, Brain Stem , Rats, Wistar , Cochlea/pathology , Apoptosis , Hair Cells, Auditory, Outer/drug effects , Hair Cells, Auditory, Outer/pathology , Protective Agents/pharmacology , Disease Models, Animal , Stereocilia/drug effects , Stereocilia/pathology , Ototoxicity/prevention & control , Hearing Tests , Antioxidants/pharmacology
Rev. méd. Minas Gerais ; 30: e-3007, 2020.
Article in Portuguese | LILACS | ID: biblio-1117837


Introdução: A associação entre perda auditiva e Diabetes Mellitus tipo 1 (DM1) é ainda pouco estudada. A perda auditiva é uma das complicações crônicas relacionadas ao grau de controle glicêmico, que os pacientes podem apresentar com a progressão da doença. Objetivo: Investigar o comprometimento auditivo por meio das emissões otoacústicas transitórias (EOAT) por banda de frequência em adolescentes com DM1 e relação com o controle glicêmico. Métodos: Foram incluídos 80 adolescentes, 50% do gênero masculino, entre 10 e 19 anos de idade: 40 com DM1 e 40 controles saudáveis, pareados por gênero e idade. Os dados clínicos e laboratoriais foram pesquisados nos prontuários médicos. O controle glicêmico foi avaliado por meio dos exames de hemoglobina glicada e os pacientes com DM1 analisados de acordo com o controle glicêmico. A avaliação auditiva foi realizada por meio da imitanciometria, audiometria, e posteriormente EOAT, em sala tratada acusticamente, pelo protocolo "TE Test" de clique não-linear (1 KHz a 4 kHz) a 80 dB NPS de intensidade (AuDX - Biologic). Resultados: As respostas às EOAT foram ausentes em 5,12% em pacientes com DM1, com diferença significativa em relação aos controles (p=0,04). A análise das EOAT por bandas de frequência mostrou maior proporção de alteração nos adolescentes com DM1 mal controlados quando comparados aos bem controlados, nas frequências de 1000Hz, 2000Hz e 3000Hz (p<0,05). Conclusão: As EOAT por bandas de frequência permitiram a identificação precoce de comprometimento auditivo em adolescentes com DM1 e mostraram associação entre DM1 mal controlado e perda auditiva. (AU)

Introduction: The association between hearing loss and type 1 diabetes mellitus (DM1) is still poorly studied. Hearing loss is one of the chronic complications related to the degree of glycemic control that patients may present with the progression of the disease. Objective: To investigate auditory impairment through transient otoacoustic emissions (TEOAE) by frequency band in adolescents with DM1 and in relation to glycemic control. Methods: Were included 80 adolescents, 50% males, between 10 and 19 years of age: 40 with DM1 and 40 healthy controls, matched by gender and age. Clinical and laboratory data were taken from the medical records. Glycemic control was evalueted by glycated hemoglobin and the patients with DM1 were analyzed according to glycemic control. To the auditory evaluation were used the immittance and audiometry, and the TEOAE. The test was performed in the acoustically treated room, the non-linear TE test protocol (1 KHz to 4 kHz) at 80 dB SPL (AuDX - Biologic ). Results: TEOAE responses were absent in 5.12% of patients with DM1, with a significant difference in relation to controls (p = 0.04). The analysis of TEOAE by frequency bands showed a higher proportion of alteration in adolescents with DM1 poorly controlled when compared to well controlled ones, in the frequencies of 1000Hz, 2000Hz and 3000Hz (p <0.05). Conclusion: TEOAE by frequency bands allowed the early identification of auditory impairment in adolescents with DM1 and showed an association between poorly controlled DM1 and hearing loss. (AU)

Humans , Male , Female , Child , Adolescent , Adult , Young Adult , Acoustic Stimulation/methods , Diabetes Mellitus, Type 1/physiopathology , Blood Glucose/metabolism , Case-Control Studies , Cross-Sectional Studies , Cochlea , Diabetes Mellitus, Type 1/complications , Hearing Loss/etiology , Hearing Tests/methods
Braz. j. otorhinolaryngol. (Impr.) ; 85(6): 766-773, Nov.-Dec. 2019. tab, graf
Article in English | LILACS | ID: biblio-1055506


Abstract Introduction: Ototoxicity refers to cellular damage or function impairment developing in the inner ear in association with any therapeutic agent or chemical substance, and still represents the principal side-effect restricting the use of cisplatin. Objective: The aim of this study was to perform a biochemical, functional and histopathological investigation of the potential protective effect of eugenol against cisplatin-induced ototoxicity. Methods: The study was performed with 24 female Sprague Dawley rats. Distortion product otoacoustic emissions tests were performed on all animals, which were randomized into four equal groups. A single intraperitoneal dose of 15 mg/kg cisplatin was administered to cisplatin group, while the eugenol group received 100 mg/kg eugenol intraperitoneal for five consecutive days. 100 mg/kg eugenol was administered to cisplatin + eugenol group for 5 days. On the third day, these rats were received a single dose of 15 mg/kg cisplatin. The control group was given 8 mL/kg/day intraperitoneal saline solution for five days. The distortion product otoacoustic emissions test was repeated 24 h after the final drug administration. All animals were sacrificed, and the cochleas were subsequently used for biochemical and histopathological examinations. Results: Cisplatin caused oxidative stress in the cochlea, impaired the cochlear structure and significantly reduced signal noise ratio levels. Administration of eugenol together with cisplatin reversed these effects and provided functional, biochemical and histopathological protection. Conclusion: The study findings represent the first indication in the literature that eugenol may protect against ototoxicity by raising levels of antioxidant enzymes and lowering those of oxidant parameters.

Resumo Introdução: A ototoxicidade refere-se ao dano celular ou comprometimento da função da orelha interna associado a qualquer agente terapêutico ou substância química e ainda representa o principal efeito colateral que restringe o uso da cisplatina. Objetivo: O objetivo deste estudo foi realizar uma investigação bioquímica, funcional e histopatológica do potencial efeito protetor do eugenol contra a ototoxicidade induzida pela cisplatina. Método: O estudo foi realizado com 24 ratos fêmeas Sprague Dawley. Testes de emissões otoacústicas por produto de distorção foram realizados em todos os animais, os quais foram randomizados em quatro grupos iguais. Uma única dose intraperitoneal de 15 mg/kg de cisplatina foi administrada ao grupo cisplatina, enquanto o grupo eugenol recebeu 100 mg/kg de eugenol intraperitoneal por cinco dias consecutivos. Foram administrados 100 mg/kg de eugenol ao grupo cisplatina + eugenol durante 5 dias. No terceiro dia, estes ratos receberam uma dose única de 15 mg/kg de cisplatina. O grupo controle recebeu 8 mL/kg/dia de solução salina intraperitoneal por cinco dias. O teste de emissões otoacústicas por produto de distorção foi repetido 24 horas após a administração final do medicamento. Todos os animais foram sacrificados e as cócleas foram posteriormente utilizadas para exames bioquímicos e histopatológicos. Resultados: A cisplatina causou estresse oxidativo na cóclea, prejudicou a estrutura coclear e reduziu significativamente os níveis da relação sinal/ruído. A administração de eugenol juntamente com a cisplatina reverteu esses efeitos e forneceu proteção funcional, bioquímica e histopatológica. Conclusão: Os achados do estudo representam a primeira indicação na literatura de que o eugenol pode proteger contra a ototoxicidade, eleva os níveis de enzimas antioxidantes e diminui os níveis dos parâmetros oxidantes.

Animals , Female , Rats , Eugenol/therapeutic use , Cisplatin/toxicity , Hearing Loss/prevention & control , Antineoplastic Agents/toxicity , Antioxidants/therapeutic use , Rats, Sprague-Dawley , Otoacoustic Emissions, Spontaneous/drug effects , Cochlea/drug effects , Cochlea/pathology , Disease Models, Animal , Hearing Loss/chemically induced
Braz. j. otorhinolaryngol. (Impr.) ; 85(3): 282-289, May-June 2019. tab, graf
Article in English | LILACS | ID: biblio-1011624


Abstract Introduction: In daily life biological systems are usually exposed to magnetic field forces at different intensities and frequencies, either directly or indirectly. Despite negative results, the therapeutic use of the low dose magnetic field has been found in recent studies. The effect of magnetic field forces on cochlear cells is not clear in the literature. Objective: In our study, we first applied in vivo pulsed magnetic fields to laboratory rats to investigate the effects on cochlea with distortion product otoacoustic emission test followed by histopathological examinations. Methods: Twelve rats were included in this study, separated into two groups as study group and control group. The rats in the study group were exposed to 40 Hz pulsed magnetic field for 1 h/day for 30 days; the hearing of the rats was controlled by otoacoustic emission test. Also, their cochleas were removed and histochemical examination was performed by Caspase-3, Caspase-9, and TUNEL methods. Results: A statistically significant difference was determined (p < 0.05) when the hearing thresholds of the groups obtained by using 5714 Hz and 8000 Hz stimuli were compared by Kruskal-Wallis test. A significant reaction was observed in the study group, especially in the outer ciliated cells during immunohistochemical examinations by using Caspase-3 and Caspase-9 methods. A significantly positive difference was determined in the study group, especially at the outer ciliated cells and the support cells of the corti organ, when compared to the control group (p < 0.05) by the TUNEL method. Conclusion: According to the results of our study, the very low dose magnetic field, which is considered to be used for therapeutic purposes recently, can cause both auditory function defects and histopathologic damage in cochlear cells.

Resumo Introdução: Os sistemas biológicos são geralmente expostos a forças de campo magnético em diferentes intensidades e frequências, direta ou indiretamente, na vida diária. Apesar dos resultados negativos, o uso terapêutico do campo magnético de baixa dose tem sido encontrado em estudos recentes. O efeito das forças do campo magnético sobre as células cocleares não está claro na literatura. Objetivo: Em nosso estudo, aplicamos pela primeira vez campos magnéticos pulsados in vivo em ratos de laboratório para investigar os efeitos na cóclea através do teste de emissão otoacústica por produto de distorção e análises histopatológicas. Método: Doze ratos foram incluídos neste estudo, os quais foram separados em dois grupos, grupo de estudo e grupo controle. Os ratos do grupo de estudo foram expostos a campo magnético pulsado de 40 Hz por 1 hora/dia por 30 dias, e a audição dos ratos foi controlada por testes de emissão otoacústica. Além disso, suas cócleas foram colhidas e o exame histoquímico foi feito pelos métodos caspase-3, caspase-9 e TUNEL. Resultados: Foi determinada uma diferença estatisticamente significante (p < 0,05) quando os limiares auditivos dos grupos obtidos por meio dos estímulos de 5714 Hz e 8000 Hz foram comparados pelo teste de Kruskal-Wallis. Uma reação significante foi observada no grupo de estudo, especialmente nas células ciliadas externas nas análises imuno-histoquímicas, com os métodos caspase-3 e caspase-9. Uma diferença significantemente positiva foi determinada no grupo de estudo, especialmente nas células ciliadas externas e nas células de suporte do órgão de Corti, quando comparadas com o grupo controle (p < 0,05) pelo método TUNEL. Conclusão: De acordo com os resultados do nosso estudo, o campo magnético de dose baixa, que tem sido considerado para uso terapêutico recentemente, pode causar defeitos na função auditiva e danos histopatológicos nas células cocleares.

Animals , Male , Rats , Cochlea/pathology , Hair Cells, Auditory, Outer/pathology , Electromagnetic Fields/adverse effects , Immunohistochemistry , Rats, Wistar , Otoacoustic Emissions, Spontaneous , Statistics, Nonparametric
Braz. j. otorhinolaryngol. (Impr.) ; 85(3): 267-274, May-June 2019. tab, graf
Article in English | LILACS | ID: biblio-1011617


Abstract Introduction: Cisplatin is an antineoplastic agent widely used in the treatment of a variety of cancers. Ototoxicity is one of the main side-effects restricting the use of cisplatin. Objective: The purpose of this study was to investigate the protective efficacy of gallic acid, in biochemical, functional and histopathological terms, against ototoxicity induced by cisplatin. Methods: Twenty-eight female Sprague Dawley rats were included. Rats were randomly assigned into four groups of seven animals each. Cisplatin group received a single intraperitoneal dose of 15 mg/kg cisplatin. Gallic acid group received intraperitoneal gallic acid at 100 mg/kg for five consecutive days. Cisplatin + gallic acid group received intraperitoneal gallic acid at 100 mg/kg for five consecutive days and a single intraperitoneal dose of 15 mg/kg cisplatin at 3rd day. A control group received 1 mL intraperitoneal saline solution for five consecutive days. Prior to drug administration, all rats were exposed to the distortion product otoacoustic emissions test. The test was repeated on the 6th day of the study. All rats were then sacrificed; the cochleas were removed and set aside for biochemical and histopathological analyses. Results: In cisplatin group, Day 6 signal noise ratio values were significantly lower than those of the other groups. Also, malondialdehyde levels in cochlear tissues were significantly higher, superoxide dismutase and glutathione peroxidase activities were significantly lower compared to the control group. Histopathologic evaluation revealed erosion in the stria vascularis, degeneration and edema in the connective tissue layer in endothelial cells, impairment of outer hair cells and a decrease in the number of these calls. In the cisplatin + gallic acid group, this biochemical, histopathological and functional changes were reversed. Conclusion: In the light of our findings, we think that gallic acid may have played a protective role against cisplatin-induced ototoxicity in rats, as indicated by the distortion product otoacoustic emissions test results, biochemical findings and immunohistochemical analyses.

Resumo Introdução: A cisplatina é um agente antineoplásico amplamente usado no tratamento de vários tipos de câncer. A ototoxicidade é um dos principais efeitos colaterais que restringem o uso da cisplatina. Objetivo: O objetivo deste estudo foi investigar a eficácia protetora do ácido gálico, em termos bioquímicos, funcionais e histopatológicos, contra a ototoxicidade induzida por cisplatina. Método: Vinte e oito ratas Sprague-Dawley foram incluídas. As ratas foram distribuídas aleatoriamente em quatro grupos de sete animais cada. O grupo cisplatina recebeu uma única dose intraperitoneal de 15 mg/kg de cisplatina. O grupo ácido gálico recebeu ácido gálico via intraperitoneal a uma dose de 100 mg/kg durante cinco dias consecutivos. O grupo cisplatina + ácido gálico recebeu ácido gálico via intraperitoneal a uma dose de 100 mg/kg durante cinco dias consecutivos e uma única dose intraperitoneal de 15 mg/kg de cisplatina no terceiro dia. O grupo controle recebeu 1 mL de solução salina via intraperitoneal por cinco dias consecutivos. Antes da administração do fármaco, todos os ratos foram expostos ao teste de emissões otoacústicas - produto de distorção. O teste foi repetido no sexto dia do estudo. Todos os ratos foram então sacrificados; as cócleas foram removidas e reservadas para análises bioquímicas e histopatológicas. Resultados: No grupo cisplatina, os valores da relação sinal-ruído do dia 6 foram significativamente mais baixos aos dos outros grupos. Além disso, os níveis de malondialdeído nos tecidos cocleares foram significativamente mais altos, e as atividades de superóxido dismutase e glutatione peroxidase foram significativamente mais baixas em comparação com o grupo controle. A avaliação histopatológica revelou erosão na estria vascular, degeneração e edema na camada de tecido conjuntivo em células endoteliais, comprometimento das células ciliadas externas e diminuição do número dessas células. No grupo cisplatina + ácido gálico, estas alterações bioquímicas, histopatológicas e funcionais foram revertidas. Conclusão: Tendo em vista os nossos achados, consideramos que o ácido gálico pode ter desempenhado um papel protetor contra a ototoxicidade induzida por cisplatina em ratas, conforme indicado pelos resultados do teste emissões otoacústicas - produto de distorção, achados bioquímicos e análises imuno-histoquímicas.

Animals , Female , Rats , Cisplatin/toxicity , Otoacoustic Emissions, Spontaneous/drug effects , Cochlea/drug effects , Cochlea/pathology , Protective Agents/administration & dosage , Gallic Acid/administration & dosage , Acoustic Stimulation , Immunohistochemistry , Rats, Sprague-Dawley , Disease Models, Animal , Injections, Intraperitoneal
Braz. j. otorhinolaryngol. (Impr.) ; 85(1): 55-62, Jan.-Feb. 2019. tab, graf
Article in English | LILACS | ID: biblio-984047


Abstract Introduction: Cisplatin is one of the main chemotherapeutic agents used for the treatment of many types of cancer. However, ototoxicity, one of the most serious side effects of cisplatin, restricts its usage. Objective: We aimed to investigate the protective effects of whortleberry extract against cisplatin-induced ototoxicity by evaluating hearing and histopathological cochlear damage and by measuring the biochemical parameters affected byoxidative stress. Methods: Forty-eight male rats were included in the study after performing Distortion Product Otoacoustic Emission test to confirm that their hearing levels were normal. The rats were randomly divided into six groups: the control group, the sham group, and, which received only whortleberry extract, only cisplatin, cisplatin + 100 mg whortleberry extract, cisplatin + 200 mg whortleberry extract, respectively. Audiologic investigation was performed by performing the Distortion Product Otoacoustic Emission test at the beginning and at the eighth day of the study. Cardiac blood samples were collected for biochemical analysis, and the rats were sacrificed to obtain cochlear histopathological specimens on the eighth day. Results: The results revealed that whortleberry protects hearing against cisplatin-induced ototoxicity independent of the dose. However, high doses of whortleberry extract are needed to prevent histopathological degeneration and oxidative stress. Conclusion: The results obtained in this study show that whortleberry extract has a protective effect against cisplatin-induced ototoxicity.

Resumo Introdução: A cisplatina é um dos principais agentes quimioterápicos utilizados para o tratamento de muitos tipos de câncer. No entanto, a ototoxicidade, um dos efeitos colaterais mais graves da cisplatina, restringe seu uso. Objetivo: Nosso objetivo foi investigar os efeitos protetores do extrato de uva-do-monte contra a ototoxicidade induzida por cisplatina, avaliar o dano auditivo e histopatológico coclear e medir os parâmetros bioquímicos afetados pelo estresse oxidativo. Método: Foram incluídos no estudo 48 ratos machos após teste de emissão otoacústica evocada por produto de distorção para confirmar que seus níveis de audição eram normais. Os ratos foram divididos aleatoriamente em seis grupos: o grupo controle, o grupo simulado, o que recebeu apenas extrato de uva-do-monte, o que recebeu apenas cisplatina, o que recebeu cisplatina + 100 mg de extrato de uva-do-monte e o que recebeu cisplatina + 200 mg de extrato de uva-do-monte, respectivamente. A investigação audiológica foi feita através do teste de emissão otoacústica de produto de distorção no início e no oitavo dia do estudo. As amostras de sangue cardíaco foram coletadas para análise bioquímica e os ratos foram sacrificados para obtenção de espécimes histopatológicos cocleares no oitavo dia. Resultados: Os resultados revelaram que o extrato de uva-do-monte protege a audição contra a ototoxicidade induzida por cisplatina, independentemente da dose. No entanto, são necessárias doses elevadas do extrato para evitar a degeneração histopatológica e o estresse oxidativo. Conclusão: Os resultados obtidos neste estudo mostram que o extrato de uva-do-monte tem um efeito protetor contra a ototoxicidade induzida por cisplatina.

Animals , Male , Cisplatin/toxicity , Cochlea/drug effects , Protective Agents/therapeutic use , Hearing/drug effects , Anthocyanins/therapeutic use , Antineoplastic Agents/toxicity , Reference Values , Acoustic Stimulation , Random Allocation , Reproducibility of Results , Treatment Outcome , Rats, Wistar , Otoacoustic Emissions, Spontaneous/drug effects , Cochlea/pathology , Oxidative Stress/drug effects , Antioxidants/therapeutic use
Int. arch. otorhinolaryngol. (Impr.) ; 23(2): 184-190, 2019. ilus, tab
Article in English | LILACS | ID: biblio-1015202


Introduction: The cochlear anatomy varies in each individual, and that has an impact on decisions regarding the insertion of electrodes. The measurement of the cochlear size is the routine examination required to choose the proper cochlear implant (CI) electrodes. Objective: To acquire normative data on the size of the cochlea (length, width, height, scala timpani [ST] height, cochlear duct length [CDL]) of CI candidates in Medan, Indonesia. Methods: This descriptive study was conducted based on high-resolution computed tomography (HRCT) temporal bone data and on HRCT temporal data manipulated to reconstruct three-dimensional (3D) multiplanar images with OsiriX MD DICOM Viewer version 9.5.1 (Pixmeo SARL, Bernex, Geneva, Switzerland) viewer of 18 patients (36 ears) who were CI candidates in Medan, Indonesia, in order to determine cochlear length (A), cochlear width, cochlear height, ST height and CDL, calculated through a simple mathematical function. Results: The average cochlear length (A) was 8.75 mm (standard deviation [SD] = 0.31 mm); the average cochlear width was 6.53 mm (SD = 0.35 mm); the average cochlear height was 3.26 mm (SD = 0.24 mm) and the average ST height at the basal cochlea was 1.00 mm (SD = 0.1mm); and 0.71 mm (SD = 0.1 mm) at the half turn of cochlea. The average total CDL was 32.45 mm (SD = 1.31 mm; range: 30.01-34.83 mm). Conclusion: The cochlear size varies in each individual; therefore, the temporal bone measurement of CI candidates using HRCT is essential: for the selection of suitable implant electrodes; to minimize cochlear damages at the insertion of the electrode arrays; and to maximize the hearing improvements (AU)

Humans , Male , Female , Child, Preschool , Child , Adolescent , Cochlea/anatomy & histology , Cochlear Duct/anatomy & histology , Temporal Bone/diagnostic imaging , Tomography, X-Ray Computed/methods , Cochlear Implantation , Imaging, Three-Dimensional , Hearing Loss, Sensorineural
Article in English | WPRIM | ID: wpr-763303


OBJECTIVES.: Sodium salicylate (SS) is well known for its ototoxic properties that induce functional and morphological changes in the cochlea and brain. Ginkgo biloba extract (GBE) has been widely used for treatment of various neurodegenerative diseases; however, its effects on salicylate-induced ototoxicity remain unclear. Herein, we examined the effects of EGb 761 (EGb), a standard form of GBE, on the plasticity of the N-methyl-D-aspartate receptor subunit 2B (GluN2B) in the inferior colliculus (IC) following SS administration. METHODS.: Seven-week-old Sprague Dawley rats (n=24) were randomly allocated to control, SS, EGb, and EGb+SS groups. The SS group received a single intraperitoneal SS injection (350 mg/kg), the EGb group received EGb orally for 5 consecutive days (40 mg/kg), and the EGb+SS group received EGb for 5 consecutive days, followed by an SS injection. The auditory brainstem responses (ABRs) were assessed at baseline and 2 hours after SS administration. GluN2B expression was examined by Western blot and immunohistochemistry. RESULTS.: There were no significant differences in ABR threshold shifts among the groups. The expression of the GluN2B protein normalized by which of glyceraldehyde 3-phosphate dehydrogenase (GAPDH) was significantly lower in the EGb+SS group, as compared to the SS group (P=0.012). Weak and diffused GluN2B immunoreactivity was detected in the IC neural cells of the EGb+SS group, while those of the SS group exhibited strong and diffused GluN2B positivity. CONCLUSION.: EGb may play a role in regulating the GluN2B expression in the IC of salicylate-induced ototoxicity model.

Blotting, Western , Brain , Cochlea , Evoked Potentials, Auditory, Brain Stem , Ginkgo biloba , Glyceraldehyde 3-Phosphate , Immunohistochemistry , Inferior Colliculi , N-Methylaspartate , Neurodegenerative Diseases , Oxidoreductases , Plastics , Rats, Sprague-Dawley , Sodium Salicylate
Article in Korean | WPRIM | ID: wpr-766793


Wernicke encephalopathy is a syndrome caused by thiamine deficiency whose three typical symptoms are ophthalomoplegia, ataxia, and confusion. There are also rare reports of bilateral hearing loss, which can be caused by damage to the bilateral inferior colliculus or thalamic lesions, or by energy failure of the cochlea. This case suggests that thiamine should be administered based on the possibility of Wernicke encephalopathy occurring in malnourished or alcoholic patients with sudden bilateral hearing loss.

Alcoholics , Ataxia , Cochlea , Hearing Loss , Hearing Loss, Bilateral , Humans , Inferior Colliculi , Thiamine , Thiamine Deficiency , Wernicke Encephalopathy
Article in English | WPRIM | ID: wpr-764226


BACKGROUND AND OBJECTIVES: Facial nerve stimulation (FNS) is a complication of cochlear implantation (CI). This study compared the thickness and density of the bone separating the upper basal turn of the cochlea (UBTC) and the labyrinthine segment of the facial nerve (LSFN) on preoperative computed tomography (CT) in patients with and without FNS after CI. SUBJECTS AND METHODS: Adult patients who underwent CI from January 2011 to February 2017 with preoperative CT at a tertiary referral hospital were considered for this retrospective case–control study. Patients were divided into two groups: with FNS (n=4) and without FNS (n=53). The density and thickness of the bone between the LSFN and UBTC were measured on preoperative CT. Charts were reviewed for other parameters. RESULTS: A statistically significant difference was seen in the thickness (p=0.007) but not in the density (p=0.125) of the bone between the UBTC and LSFN. Four patients had FNS at the mid-range electrode arrays, and one of them additionally had FNS at the basal arrays. CONCLUSIONS: Decreased thickness of the bone between the UBTC and LSFN can explain postoperative FNS, confirming the histologic and radiologic findings in previous studies, which indicated that the thickness of the temporal bone between the LSFN and UBTC is less in patients who experience FNS. While the density in this region was also less, it was not statistically significant.

Adult , Cochlea , Cochlear Implantation , Cochlear Implants , Electric Stimulation , Electrodes , Facial Nerve , Humans , Retrospective Studies , Temporal Bone , Tertiary Care Centers
Article in English | WPRIM | ID: wpr-764209


BACKGROUND AND OBJECTIVES: Knowing the ototoxic potential of the agents used in medical treatments is important for the protection of hearing. Although we have knowledge regarding some effects of dexmedetomidine, which is an anesthetic-sparing drug, its influence over the hearing system has never been studied and is obscure yet. The aim of this study is to determine the effects of intravenous dexmedetomidine application during sevoflurane anesthesia on otoacoustic emissions (OAEs). SUBJECTS AND METHODS: This prospective randomized study was performed on 60 patients (34 male, 26 female, mean age: 30.6±9.2 years) who were scheduled for an elective surgery under general anesthesia and the patients were enrolled and randomly divided into 2 groups. They received dexmedetomidine (Group D) or Saline (Group S) infusion during a standardized Sevoflurane anesthesia. Transient and distortion product OAEs were measured preoperatively and postoperatively (24th hour). OAE results were compared within and between groups. RESULTS: In group D postoperative OAEs were lower than preoperative OAEs and postoperative levels of group S, especially at low frequencies (p<0.05). CONCLUSIONS: Dexmedetomidine infusion affects the micromechanical function of cochlea especially in the low-frequency region. Dexmedetomidine should be carefully used during general anesthesia to avoid its probable harmful effects on cochlear micromechanics.

Adrenergic alpha-2 Receptor Agonists , Anesthesia , Anesthesia, General , Cochlea , Dexmedetomidine , Female , Hearing , Humans , Male , Prospective Studies
Article in English | WPRIM | ID: wpr-741450


OBJECTIVE: To summarize the high-resolution computed tomography (HRCT) and magnetic resonance imaging (HRMRI) features of duplicated internal auditory canals (DIACs). MATERIALS AND METHODS: Ear HRCT data of 64813 patients with sensorineural hearing loss (SNHL), obtained between August 2009 and November 2017, were reviewed. Among these patients, 12 (13 ears) were found to have DIACs, 9 of whom underwent HRMRI. Their images were evaluated by two otoradiologists. RESULTS: The rate of occurrence of DIAC among SNHL patients was 0.019% (12/64813). The internal auditory canals of 13 ears were divided into double canals by complete (n = 6) and incomplete (n = 7) bony septa, with varied orientations ranging from horizontal to approximately vertical. All of the anterosuperior canals extended into the facial nerve (FN) canal, except for 1, which also extended to the vestibule. The posteroinferior canals ended in the cochlea and vestibule, except for 2, which also connected to the FN canals. Magnetic resonance images revealed that 77.8% (7/9) and 22.2% (2/9) of vestibulocochlear nerves (VCNs) were aplastic and hypoplastic, respectively. Furthermore, 88.9% (8/9) of FNs were normal, except for 1, which was hypoplastic. All of the affected ears also had other ear anomalies: a narrow, bony cochlear nerve canal was the most common other anomaly, accounting for 92.3% (12/13). Malformations of other systems were not found. CONCLUSION: Double-canal appearance is a characteristic finding of DIAC on HRCT, and it is usually accompanied by other ear anomalies. The VCN usually appears aplastic, with a normal FN, on HRMRI.

Cochlea , Cochlear Nerve , Ear , Facial Nerve , Hearing Loss, Sensorineural , Humans , Magnetic Resonance Imaging , Vestibulocochlear Nerve
Article in English | WPRIM | ID: wpr-739233


OBJECTIVES: Hearing loss disrupts the balance of auditory-somatosensory inputs in the cochlear nucleus (CN) of the brainstem, which has been suggested to be a mechanism of tinnitus. This disruption results from maladaptive auditory-somatosensory plasticity, which is a form of axonal sprouting. Axonal sprouting is promoted by transforming growth factor (TGF)-β signaling, which can be inhibited by losartan. We investigated whether losartan prevents maladaptive auditory-somatosensory plasticity after hearing loss. METHODS: The study consisted of two stages: determining the time course of auditory-somatosensory plasticity following hearing loss and preventing auditory-somatosensory plasticity using losartan. In the first stage, rats were randomly divided into two groups: a control group that underwent a sham operation and a deaf group that underwent cochlea ablation on the left side. CNs were harvested 1 and 2 weeks after surgery. In the second stage, rats were randomly divided into either a saline group that underwent cochlear ablation on the left side and received normal saline or a losartan group that underwent cochlear ablation on the left side and received losartan. CNs were harvested 2 weeks after surgery. Hearing was estimated with auditory brainstem responses (ABRs). Western blotting was performed for vesicular glutamate transporter 1 (VGLUT1), reflecting auditory input; vesicular glutamate transporter 2 (VGLUT2), reflecting somatosensory input; growth-associated protein 43 (GAP-43), reflecting axonal sprouting; and p-Smad2/3. RESULTS: Baseline ABR thresholds before surgery ranged from 20 to 35 dB sound pressure level. After cochlear ablation, ABR thresholds were higher than 80 dB. In the first experiment, VGLUT2/VGLUT1 ratios did not differ significantly between the control and deaf groups 1 week after surgery. At 2 weeks after surgery, the deaf group had a significantly higher VGLUT2/VGLUT1 ratio compared to the control group. In the second experiment, the losartan group had a significantly lower VGLUT2/VGLUT1 ratio along with significantly lower p-Smad3 and GAP-43 levels compared to the saline group. CONCLUSION: Losartan might prevent axonal sprouting after hearing loss by blocking TGF-β signaling thereby preventing maladaptive auditory-somatosensory plasticity.

Animals , Axons , Blotting, Western , Brain Stem , Cochlea , Cochlear Nucleus , Evoked Potentials, Auditory, Brain Stem , GAP-43 Protein , Hearing Loss , Hearing , Losartan , Plastics , Rats , Tinnitus , Transforming Growth Factors , Vesicular Glutamate Transport Protein 1 , Vesicular Glutamate Transport Protein 2
Article in English | WPRIM | ID: wpr-739230


OBJECTIVES: The energy consumption process of cochlea and neural signal transduction along the auditory pathway are highly dependent on blood oxygen supply. At present, it is under debate on whether the obstructive sleep apnea syndrome (OSAS) would affect the auditory function since the patients suffer from low oxygen saturation. Moreover, it is difficult to detect the functional state of auditory in less severe stage of OSAS. Recently, speech-evoked auditory brainstem response (speech-ABR) has been reported to be a new electrophysiological tool in characterizing the auditory dysfunction. The aim of the present study is to evaluate the auditory processes in adult patients with mild and moderate OSAS by speech-ABR. METHODS: An experimental group of 31 patients with mild to moderate OSAS, and a control group without OSAS diagnosed by apnea hypopnea index in polysomnogram were recruited. All participants underwent otologic examinations and tests of pure-tone audiogram, distortion product otoacoustic emissions, click-evoked auditory brainstem response (click-ABR) and speech-ABR, respectively. RESULTS: The results of pure-tone audiogram, distortion product otoacoustic emissions, and click-ABR in OSAS group showed no significant differences compared with the control group (P>0.05). Speech-ABRs for OSAS participants and controls showed similar morphological waveforms and typical peak structures. There were significant group differences for the onset and offset transient peaks (P < 0.05), where OSAS group had longer latencies for peak V (6.69± 0.33 ms vs. 6.39±0.23 ms), peak C (13.48±0.30 ms vs. 13.31±0.23 ms), and peak O (48.27±0.39 ms vs. 47.60± 0.40 ms) compared to the control group. The latency of these peaks showed significant correlations with apnea hypopnea index for peak V (r=0.37, P=0.040), peak C (r=0.36, P=0.045), as well as peak O (r=0.55, P=0.001). CONCLUSION: These findings indicate that some auditory dysfunctions may be present in patients with mild and moderate OSAS, and the damages were aggravated with the severity of OSAS, which suggests that speech-ABR may be a potential biomarker in the diagnosis and evaluation at early stage of OSAS.

Adult , Hypoxia , Apnea , Auditory Pathways , Cochlea , Diagnosis , Evoked Potentials, Auditory, Brain Stem , Humans , Oxygen , Polysomnography , Signal Transduction , Sleep Apnea, Obstructive
Rev. otorrinolaringol. cir. cabeza cuello ; 78(4): 369-377, dic. 2018. tab, graf
Article in Spanish | LILACS | ID: biblio-985741


RESUMEN Introducción: Las zonas cocleares muertas son áreas de la membrana basilar donde las células ciliadas y/o fibras del nervio auditivo no son funcionales, lo que puede alterar el análisis temporal de una señal acústica. Los efectos funcionales que podrían generar aún no son claros, y establecerlos a través del uso de cuestionarios de autopercepción, proporcionaría información de utilidad para el manejo audiológico de los pacientes. Objetivo: Determinar la relación entre la presencia de zonas cocleares muertas y la autopercepción de las habilidades auditivas en adultos con hipoacusia sensorioneural bilateral. Material y método: Se evaluaron 20 sujetos con hipoacusia bilateral simétrica, entre 51 y 75 años, sin antecedentes de uso de audífonos. Las zonas cocleares muertas fueron evaluadas mediante la prueba TEN en 1, 2, 3 y 4 kHz; y la autopercepción de habilidades auditivas fue medida en los participantes a través del cuestionario de doce preguntas, IROS12. Resultados: La presencia de zonas cocleares muertas se observó en 10 pacientes. No existiendo una diferencia significativa entre grupos, sin embargo, se observaron puntuaciones más bajas de IROS12 en sujetos con zonas cocleares muertas. Conclusiones: La percepción de dificultades auditivas de individuos que presentan una hipoacusia sensorioneural bilateral simétrica moderada, con presencia de zonas cocleares muertas, no difiere significativamente de aquellos individuos que no presentan zonas cocleares muertas.

ABSTRACT Introduction: Cochlear dead regions are areas of the basilar membrane where the hair cells and/or auditory nerve fibers are not functional, which can alter the temporal analysis of an acoustic signal. The functional effects that could generate still are not entirely clear, and set through the use of self-perception questionnaires, provide useful information for audiological management of patients. Aim: To investigate the relationship between the presence of cochlear dead regions and the self-reported of listening difficulties of adults with bilateral sensorineural hearing loss. Material and Method: Twenty adults with symmetric bilateral sensorineural hearing loss, aged 51 to 75 years were tested, without previous story of use of hearing aids. Cochlear dead regions were tested using the TEN test at 1, 2, 3 and 4 kHz. The questionnaire of twelve questions, IROS12, was applied to the participants. Results: Cochlear dead regions were present in 10 participants. No significant differences were observed between groups, however lower IROS12 scores were observed in those who had present of dead regions. Conclusion: The perception of hearing difficulties in individuals with bilateral sensorineural hearing loss with cochlear dead regions did not differ significantly from those individuals without cochlear dead regions.

Humans , Male , Female , Middle Aged , Aged , Cochlea/physiopathology , Hearing Loss, Bilateral/physiopathology , Hearing Loss, Sensorineural/physiopathology , Self Concept , Audiometry, Pure-Tone , Surveys and Questionnaires