Effects of hyperbaric oxygen treatment on auditory hair cells after acute noise damage

Autor(es)

Colombari, Gleice Cristina ^[1] ; Rossato, Maria ^[1] ; Feres, Omar ^{[1, 2]} ; Hyppolito, Miguel Angelo ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Div Otorhinolaryngol, Dept Ophthalmol Otorhinolaryngol & Head & Neck Su, Fac Med Ribeirao Preto, BR-14049900 Ribeirao Preto, SP - Brazil

^[2] Univ Sao Paulo, Div Surg, Dept Anat & Surg, Fac Med Ribeirao Preto, BR-14049900 Ribeirao Preto, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: EUROPEAN ARCHIVES OF OTO-RHINO-LARYNGOLOGY; v. 268, n. 1, p. 49-56, JAN 2011.
• Citações Web of Science: 13

Resumo

Acute acoustic trauma (AAT) is a sudden sensorineural hearing loss caused by exposure of the hearing organ to acoustic overstimulation, typically an intense sound impulse, hyperbaric oxygen therapy (HOT), which favors repair of the microcirculation, can be potentially used to treat it. Hence, this study aimed to assess the effects of HOT on guinea pigs exposed to acoustic trauma. Fifteen guinea pigs were exposed to noise in the 4-kHz range with intensity of 110 dB sound level pressure for 72 h. They were assessed by brainstem auditory evoked potential (BAEP) and by distortion product otoacoustic emission (DPOAE) before and after exposure and after HOT at 2.0 absolute atmospheres for 1 h. The cochleae were then analyzed using scanning electron microscopy (SEM). There was a statistically significant difference in the signal-to-noise ratio of the DPOAE amplitudes for the 1- to 4-kHz frequencies and the SEM findings revealed damaged outer hair cells (OHC) after exposure to noise, with recovery after HOT (p = 0.0159), which did not occur on thresholds and amplitudes to BAEP (p = 0.1593). The electrophysiological BAEP data did not demonstrate effectiveness of HOT against AAT damage. However, there was improvement of the anatomical pattern of damage detected by SEM, with a significant reduction of the number of injured cochlear OHC and their functionality detected by DPOAE. (AU)

• Processo FAPESP: 07/59213-2 - Efeito otoprotetor da oxigenoterapia hiperbárica (OHB) à lesão pelo ruído
• Beneficiário: Gleice Cristina Colombari
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica