Cochlear Function in Adults Exposed to Severe Acute Respiratory Syndrome Coronavirus 2.

INTRODUCTION: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a viral infection with a wide variety of symptoms, including fever, coughing, sneezing, fatigue, and a loss of taste and smell. Moreover, there are some recent studies that investigate the effects of SARS-CoV-2 on hearing and auditory performance. With this current study, we investigate the early effects of the coronavirus disease on hair cells in the cochlea. METHODS: In the current study, there were 25 subjects (17 females, 8 males) who tested positive for polymerase chain reaction on nasopharyngeal swabs. They had reported normal auditory functions and no history of otology before SARS-CoV-2. To determine auditory functions, pure-tone audiometry, otoacoustic emissions (OAE) tests, and threshold equalizing noise (TEN) tests were used. RESULTS: Although the hearing thresholds increased at higher frequencies, they were within normal limits according to four-frequency pure-tone averages. All participants had normal OAE, and there were no detected dead regions for any of the subjects. Even so, there were significant increases in hearing thresholds in TEN. CONCLUSION: There is no cochlear dysfunction discovered by OAE and TEN in SARS-CoV-2-affected individuals. Nonetheless, the increase in hearing thresholds at higher frequencies, other than the pure-tone average frequencies detected by TEN, and the decrease in the presence of detected OAE could be related to deterioration in the basal part of the cochlea.

Evaluation of the efferent auditory system in COVID-19 adult patients.

BACKGROUND: The short- and long-term effects of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection on the medial olivocochlear reflex and outer hair cells in the cochlea remain largely unclear. AIMS: The aim of this study was to investigate the efferent auditory system effects in adult patients with COVID-19. MATERIALS AND METHODS: The study included 18-50 years old 44 volunteers: 26 individuals (52 ears) with COVID-19 in the study group and 18 healthy individuals (36 ears) in the control group. Otolaryngological examination, immitancemetric evaluation, distortion product otoacoustic emission (DPOAE), contralateral acoustic stimulation with DPOAE, audiometric evaluation, and high frequency audiometric evaluation were performed in all individuals participating in the study. RESULTS: In our study, patients with COVID-19 had significantly lower DPOAE results with or without broadband noise at only 6 kHz frequency and contralateral suppression results at all frequencies compared to healthy individuals. A statistically significant difference was found between the study and control groups according to whether the participants had a response in the high frequency audiometry at 12 and 16 kHz frequencies. CONCLUSIONS: COVID-19 affects many systems in the body. As a result of the findings obtained in the present study, it is shown that the auditory efferent system may also be affected.

Does SARS-CoV-2 affect cochlear functions in children?

OBJECTIVES: To determine the influence of coronavirus disease-19 (COVID-19) on cochlear tasks of children who had COVID-19 previously, and the relevance among disease seriousness and cochlear involvement by otoacoustic emissions (OAEs). METHODS: The study included 24 hospitalized children after COVID-19 diagnosis, 23 pediatrics that received outpatient treatment, and 21 children who were without COVID-19 diagnosis as the control group between June 2021 and July 2021. Transient evoked otoacoustic emission (TEOAE), distortion product otoacoustic emission, and contrlateral suppression of otoacoustic emission measurements were carried out for each child. Symptoms of patients, the treatments they received, and the duration of hospitalization of the children in the hospitalized group were recorded. RESULTS: The comparison of TEOAE test results under masking showed a considerable difference between 3 groups at 1 kHz (p=0.033) and 4 kHz (p=0.021) frequencies (p<0.05). Distortion product otoacoustic emission test results of hospitalized outpatient and control group showed a statistically significant difference at 2 kHz among themselves (p=0.009). CONCLUSION: Our results suggest that severe acute respiratory syndrome coronavirus-2 may influence the medial olivocochlear system of children and have irreversible effects on the cochlear functions. Early detection of problems that may affect cochlear functions is a special critical task, especially in children, who are a particularly vulnerable group in terms of hearing and related speech problems.

Radiological measurement of cochlear dimensions in cochlear hypoplasia and its effect on cochlear implant selection.

OBJECTIVE: To determine the effect of cochlear dimensions on cochlear implant selection in cochlear hypoplasia patients. METHODS: Temporal bone computed tomography images of 36 patients diagnosed with cochlear hypoplasia between 2010 and 2016 were retrospectively reviewed and compared with those of 40 controls without sensorineural hearing loss. RESULTS: Basal turn length and mid-modiolar height were significantly lower in the cochlear hypoplasia patients with subtypes I, II and III than in the control group (p < 0.001). Mid-scalar length was significantly shorter in subtype I-III patients as compared with the control group (p < 0.001). In addition, cochlear canal length (measured along the lateral wall) was significantly shorter in subtype I-IV patients than in the control group (subtypes I-III, p < 0.001; subtype IV, p = 0.002). CONCLUSION: Cochlear hypoplasia should be considered if basal turn length is less than 7.5 mm and mid-modiolar height is less than 3.42 mm. The cochlear implant should be selected according to cochlear hypoplasia subgroup. It is critically important to differentiate subtype II from incomplete partition type I and subtype III from a normal cochlea, to ensure the most appropriate implant electrode selection so as to optimise cochlear implantation outcomes.

Evaluation of cochlear functions in infants exposed to SARS-CoV-2 intrauterine.

PURPOSE: The novel coronavirus (SARS-CoV-2) caused an acute respiratory illness named COVID-19 and the disease spread all over the World. Fever, cough, fatigue, gastrointestinal infection symptoms form the main clinical symptoms. Pregnants and newborns form a vulnerable population and urgent measures must be addressed. Studies about the effect of COVID-19 on pregnant women, developing fetuses, and infants are limited. Various viral diseases can cause congenital or acquired, unilateral or bilateral hearing loss. METHODS: 37 infants whose mother was pregnant between March 2020 and December 2020 and were born after the diagnosis of COVID- 19 during pregnancy and 36 healthy infants were included in the study. Transient evoked otoacoustic emission (TEOAE), distortion product otoacoustic emission (DPOAE) and contralateral suppression of OAE (CLS OAE) tests were performed on all infants. RESULTS: According to the TEOAE results of patients and controls in the silent a statistically significant difference was observed between the two groups at 3 kHz and 4 kHz (p < 0.05). Contralateral suppression of OAE test results of patients and controls a statistically significant difference was found in all frequencies (p< 0.05). Suppression was much more effective at all frequencies in the normal group than patient group. This difference was found to be more significant at higher frequencies (2,3 and 4 kHz) (p < 0.001). CONCLUSIONS: Our results suggest an insufficiency in medial olivocochlear efferent system in infants exposed to SARS-CoV-2 intrauterine. Cochlear functions should be examined in infants whose mothers had COVID-19.

Expression of ACE2, TMPRSS2, and Furin in Mouse Ear Tissue, and the Implications for SARS-CoV-2 Infection.

OBJECTIVES/HYPOTHESIS: Intracellular entry of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) depends on the interaction between its spike protein with the cellular receptor angiotensin-converting enzyme 2 (ACE2) and depends on Furin-mediated spike protein cleavage and spike protein priming by host cell proteases, including transmembrane protease serine 2 (TMPRSS2). As the expression of ACE2, TMPRSS2, and Furin in the middle and inner ear remain unclear, we analyzed the expression of these proteins in mouse ear tissues. STUDY DESIGN: Animal Research. METHODS: We performed immunohistochemical analysis to examine the distribution of ACE2, TMPRSS2, and Furin in the Eustachian tube, middle ear spaces, and cochlea of mice. RESULTS: ACE2 was present in the nucleus of the epithelium of the middle ear and Eustachian tube, as well as in some nuclei of the hair cells in the organ of Corti, in the stria vascularis, and the spiral ganglion cells. ACE2 was also expressed in the cytoplasm of the stria vascularis. TMPRSS2 was expressed in both the nucleus and cytoplasm in the middle spaces, with the expression being stronger in the nucleus in the mucosal epithelium of the middle ear spaces and Eustachian tube. TMPRSS2 was present in the cytoplasm in the organ of Corti and stria vascularis and in the nucleus and cytoplasm in the spiral ganglion. Furin was expressed in the cytoplasm in the middle ear spaces, Eustachian tube, and cochlea. CONCLUSIONS: ACE2, TMPRSS2, and Furin are diffusely present in the Eustachian tube, middle ear spaces, and cochlea, suggesting that these tissues are susceptible to SARS-CoV-2 infection. LEVEL OF EVIDENCE: NA Laryngoscope, 131:E2013-E2017, 2021.