ABSTRACT
Abstract Introduction Distortion product otoacoustic emissions (DPOAE) and their suppression may be considered useful in monitoring cochlear function and the efferent auditory pathway inhibitory effect. Nonetheless, the establishment of reliable parameters of response variations is of great importance. Objectives To verify the replicability of test and retest in the research of the inhibitory effect of the efferent pathway using contralateral suppressing stimulus during DPOAE recording for clinical applicability. Methods Cross-sectional study with 48 volunteers, aged 18 to 30 years, with normal audiometric thresholds. The procedures included were audiometric and immittance measures to overrule any conductive or sensorineural conditions and DPOAE recordings without and with contralateral suppression with a 60 dBHL white noise. Distortion product otoacoustic emissions amplitudes were analyzed and compared in both conditions with Wilcoxon test, and the Spearman correlation test was used to assess test-retest reliability. Results The comparative analysis showed differences between amplitudes in test and retest conditions only in 1,500 Hz for DPOAE measures with all other tested frequencies showing no differences, and no difference was observed in all recorded frequencies in the test and retest comparison for DPOAE suppression. The degree of correlation between test and retest of DPOAE amplitude was good at 6,000 Hz and strong (r > 0.880) at the other frequencies. For DPOAE with suppression, all frequencies presented strong correlation between test and retest: 1,500 Hz (r = 0.880), 2,000 Hz (r = 0.882), 3,000 Hz (r = 0.940), and 6,000 Hz (r = 0.957). Conclusions The study found good replicability in contralateral suppression of DPOAE with potential clinical applicability, and we recommend conducting the test from 2000Hz to higher frequencies for more reliable results.
ABSTRACT
Resumen La hiperacusia se define como la intolerancia a ciertos sonidos cotidianos que causa angustia y discapacidad significativas en las actividades sociales, ocupacionales, recreativas y otras actividades cotidianas. Los sonidos pueden percibirse como incómodamente fuertes, desagradables, atemorizantes o dolorosos. Se encuentra presente en aproximadamente un 3% población general, y aumenta significativamente en trastornos del espectro autista (TEA), alcanzando entre un 15% a 40%. Los mecanismos fisiopatológicos no son del todo claros, pero se ha propuesto, una alteración en el funcionamiento de mecanismos reflejos y de regulación, tanto a nivel de la vía auditiva periférica, como central, incluyendo estructuras no relacionadas directamente con la vía auditiva. El siguiente texto tiene como objetivo analizar la relación entre hiperacusia y TEA, enfatizando en la frecuencia en que se presentan como comorbilidades, en los posibles mecanismos fisiopatológicos, y en actualizaciones en el abordaje diagnóstico y terapéutico. Se realiza una revisión bibliográfica cualitativa en Pubmed con artículos entre los años 2008-2020 utilizando los términos: "hyperacusis autism", "sistema olivococlear", arrojando 39 artículos, de los cuales se seleccionaron en base a la temática de cada uno, evaluada por los autores. A pesar de una significativa relación entre hiperacusia y TEA, los mecanismos fisiopatológicos de ambas patologías siguen siendo un misterio. Existen estudios que sugieren pruebas de screening no invasivas que relacionan ambas patologías, pero debido a los sesgos de selección, todavía no son factibles de usar en forma universal. El abordaje terapéutico ha sido poco explorado, y no se dispone de fármacos que hayan demostrado su efectividad, por el contrario, algunos de ellos empeoran la sintomatología. Se recomienda al tratante, seguir un camino largo, en conjunto con el paciente, donde las terapias no farmacológicas como la terapia cognitivo conductual han mostrado tener buenos resultados.
Abstract Hyperacusis is defined as intolerance to certain sounds that causes significant distress and disability in social, occupational, recreational and other activities. Sounds can be perceived as uncomfortably loud, unpleasant, frightening, or painful. It is present in approximately 3% of the general population, and increases significantly in autism spectrum disorders (ASD), between 15% and 40%. The pathophysiological mechanisms are not entirely clear, but an alteration in the functioning of reflex and regulatory mechanisms has been proposed, both at the peripheral and central auditory pathways, including structures not directly related to the auditory pathway. The therapeutic approach has been little explored as there are no drugs that have demonstrated their effectiveness, on the contrary, some of them worsen the symptoms. The practitioner is recommended to follow a long path, in conjunction with the patient, where non-pharmacological therapies such as cognitive behavioral therapy have been shown to have good results. The following text shows a review of the literature with articles referring to the subject between the years 2008-2019.