Evaluation of the effects of Covid-19 on cochleovestibular system with audiovestibular tests.

PURPOSE: The purpose of the present study was to investigate the effects of COVID-19 on audiovestibular system with Transiently Evoked Distortion Otoacoustic Emissions (TOAE), Distortion Product Otoacoustic Emissions (DPOAE), video head impulse test (vHIT) and caloric test. METHODS: Audiovestibular findings of 24 patients with moderate/severe COVID-19 and 24 healthy controls were compared using pure tone audiometry, tympanometry, TOAE, DPOAE, caloric test, and vHIT. RESULTS: On audiometry, the pure tone averages of the COVID-19 patients were higher than the controls (P = .038). The TEOAE amplitudes at 4000 and 5000 Hz (P = .006 and P < .01), and DPOAE amplitudes at 3000, 6000, and 8000 Hz (P < .001, P = .003 and P < .001) were significantly lower in COVID-19 patients compared to the controls. On vestibular tests, there was no significant difference between the caloric test results of the patients and the controls (P > .05). On vHIT testing, amplitudes of right semicircular canal was found to be significantly lower in COVID-19 group compared to the control group (P = .008). CONCLUSION: COVID-19 may affect inner ear functions causing a subtle damage in the outer hair cells and lateral semicircular canals. It must be kept in mind that COVID-19 may cause cochleovestibular problems.

Assessment of balance after recovery from Covid-19 disease.

OBJECTIVE: To answer the question whether balance related systems have been affected in adults who recovered from Covid-19 disease. This is the first case-control study to assess balance objectively and quantitatively in Covid-19 disease. METHODS: Thirty-seven patients who recovered from Covid-19 disease and 30 healthy controls were compared using Dizziness Handicap Inventory (DHI), Computerized Dynamic Posturography (CDP), Vestibular Evoked Myogenic Potentials(VEMP) and Video Head Impulse Test (v-HIT). RESULTS: On CDP, the composite and visual general scores of the patients were significantly lower than controls (p<0.01). The v-HIT gains of the patients significantly decreased in the vertical semicircular canals compared to controls (p<0.01).There was a significant difference between the patients and controls regarding the absence of o-VEMPs (p<0.01) while the amplitudes and latencies were similar between the groups (p>0.05). Decreased P1/N1 amplitudes and elongated N1 latencies were found on c-VEMP testing (p<0.05). Anosmia, taste disorder and gender were not associated with subjective and objective test results (p>0.05). CONCLUSION: The Covid-19 disease can cause dizziness rather that incapacitating vertigo. Dizziness can be seen in almost one-fifth of the adult covid19 out-patients, which may be due to involvement of vestibular and visual systems,ortheir central connections. The squeals created in the balance related systems may be irreversible as they have persisted after the recovery of the patients. It is also plausible to anticipate more severe condition in the older patients who were treated in the intensive care units. In the long term follow up of the survivors, the need for balance rehabilitation programs should be remembered in order to minimize risks of falling down.