Application of evoked response audiometry for specifying aberrant gamma oscillations in schizophrenia

Gamma oscillations probed using auditory steady-state response (ASSR) are promising clinical biomarkers that may give rise to novel therapeutic interventions for schizophrenia. Optimizing clinical settings for these biomarker-driven interventions will require a quick and easy assessment system for gamma oscillations in psychiatry. ASSR has been used in clinical otolaryngology for evoked response audiometry (ERA) in order to judge hearing loss by focusing on the phase-locked response detectability via an automated analysis system. Herein, a standard ERA system with 40- and 46-Hz ASSRs was applied to evaluate the brain pathophysiology of patients with schizophrenia. Both ASSRs in the ERA system showed excellent detectability regarding the phase-locked response in healthy subjects and sharply captured the deficits of the phase-locked response caused by aberrant gamma oscillations in individuals with schizophrenia. These findings demonstrate the capability of the ERA system to specify patients who have aberrant gamma oscillations. The ERA system may have a potential to serve as a real-world clinical medium for upcoming biomarker-driven therapeutics in psychiatry.

Application of otoacoustic emissions and brainstem evoked response audiometry in newborn hearing screening

<p class="abstract"><strong>Background: </strong>Newborn hearing screening was conducted in a tertiary care hospital in a step by step manner using otoacoustic emissions (OAE) and brainstem evoked response audiometry (BERA) and details were recorded.</p><p class="abstract"><strong>Methods:</strong> A prospective institutional based study was conducted. All the newborns born in the hospital over a period of 18 months from December 2018 to May 2020 were considered in the study. Healthy newborns were screened bedside within 24 hours of delivery and NICU (Neonatal Intensive Care Unit) babies were screened in the NICU. Handheld OAE apparatus was used as the initial screening tool. A total of 3 OAEs were done for babies with a “refer” result in the OAEs, which were done 1 month apart. Babies with a “refer” in the third OAE were subjected for BERA.</p><p class="abstract"><strong>Results:</strong> A total of 14226 babies were screened at 24-48 hours of birth. Among them, 13,069 babies passed the first OAE screening in both ears. Remaining babies were referred for further follow-up. After subsequent follow-ups and successive testing, 11 babies were found to have hearing loss, which was diagnosed within 4-5 months of the child’s birth.</p><p class="abstract"><strong>Conclusions: </strong>Universal newborn hearing screening is the need of the day. OAE is an effective screening tool for newborn hearing loss. When complemented by BERA, majority of congenitally deaf babies can be diagnosed at a very early age. This helps in early intervention.</p>

Does gestational diabetes mellitus affect the hearing of the baby?

<p><strong>Background: </strong>Hearing screening results of babies born to mothers with and without gestational diabetes mellitus done within 24-48 hours of delivery using otoacoustic emissions was compared. Babies who failed the screening were recalled for further testing.<strong></strong></p><p><strong>Methods: </strong>A prospective institutional based study was conducted between December 2018 and May 2020. All the babies were screened for hearing impairment using handheld OAE apparatus within 24-48 hours of delivery. History of gestational diabetes mellitus in the mother was enquired. Any baby with a “refer” result in the OAE study was recalled for a repeat OAE testing after a month. This was repeated two more times if the baby failed the test every time. In case of failing the test for the third time, the baby was sent for brainstem evoked response audiometry for confirmation of hearing loss.<strong></strong></p><p><strong>Results: </strong>Screening was done for 14226 babies. Among them, 44 babies were born to mothers with gestational diabetes mellitus. The hearing screening results did not show a significant association between gestational diabetes mellitus and hearing impairment in the baby.<strong></strong></p><p><strong>Conclusions: </strong>Gestational diabetes is considered as one of the risk factors for deafness in the baby. This study could not establish such a relationship.<strong></strong></p>

Comparative study of brainstem evoked response audiometry in diabetic patients and non-diabetic subjects to assess the involvement of central auditory pathway

<p><strong>Background: </strong>Diabetes mellitus (DM) which is prevalent in world is associated with sensorineural hearing loss. Brainstem evoked response audiometry (BERA) is a simple, non-invasive procedure to detect early impairment of acoustic nerve and auditory pathway. The present study is under taken to evaluate the impact of DM on BERA parameters. Aim of the study was to compare the BERA of diabetic patients to those of age and gender matched controls to assess the involvement of central auditory pathway.</p><p><strong>Methods</strong>: A cross sectional study was conducted on 35 diabetic patients, aged 35 to 55 years, who were on treatment for at least 2 years, and 35 age and sex matched control participants, were subjected for BERA at 70,80 and 90 dB. The waveforms, absolute latency of wave I, wave III, wave V and interwave/ inter peak latency of I-III, III-V and I-V were analyzed with respect to both groups.</p><p><strong>Results</strong>: The absolute latency of wave III and wave V, interpeak/ interwave latency of I-III, interpeak/ interwave latency of I-V, III-V and absolute latency of wave V were highly significant at corresponding tested stimuli in the diabetic group compared to the control group.</p><p><strong>Conclusions</strong>: Early involvement of central auditory pathway in diabetic patients, can be detected with fair accuracy with auditory evoked potential studies; if done on a regular basis warrants meticulous glycemic control and prevents further damage.</p>

Hearing Screening of Newborns using Distortion Product Otoacoustic Emissions

Introduction The present study was devised to estimate the prevalence of neonatal hearing loss and document the importance of using DPOAE as a screening tool for identifying hearing loss in newborns. Materials and Methods This hospital based descriptive study was conducted from August 2018 to August 2019. A total of 928 newborn babies were included in the study. These newborn babies were subjected to hearing screening by distortion product otoacoustic emissions (DPOAE) at 24-72 hrs after birth. For pass cases, no further testing was done. For refer cases, repeat testing with DPOAE was done within 15-30 days. Newborns with refer result on repeat DPOAE testing were subjected to Brainstem evoked response audiometry (BERA) within 3 months to confirm hearing loss. Results Nine hundred and twenty eight newborn babies were screened by DPOAE. 851 newborns passed the first DPOAE hearing screening and 77 newborns gave refer result. 21 newborns were lost to follow-up. 56 newborns underwent repeat DPOAE testing and 5 newborns were referred for BERA. Amongst the 5 newborns who underwent BERA testing, one newborn was diagnosed with bilateral profound hearing loss. Hence, the prevalence of hearing loss of 1.08 per thousand newborn babies was estimated in this study. Conclusion Hearing screening of newborns using DPOAE followed by BERA in refer cases to confirm hearing loss is useful for early detection followed by timely intervention and rehabilitation.

Role of Brainstem Evoked Response Audiometry in Evaluating Sensorineural Hearing Loss in Diabetic Patients

Introduction Diabetes has become a global epidemic. Hearing loss has been long associated with diabetes. Brainstem Evoked Response Audiometry (BERA) is an objective, non-invasive, electro diagnostic test that not only evaluates the functional integrity of the subcortical auditory pathway but also provides topo-diagnosis of hearing loss. This study aims to identify the role BERA in detecting hearing loss early in diabetic patients.Materials and Methods In this study a total of 210 patients were taken and subjected to blood glucose levels followed by PTA were divided into two groups. Group I (n=105) consisted of diabetic patients with sensorineural hearing loss (SNHL) and Group II (n=105) had age and sex matched non-diabetics with SNHL. All the patients were evaluated with BERA.Results All the patients were subjected to Brain Stem Evoked Response Audiometry (BERA). Absolute latency of Wave I, III, V, I-III, III-V and I-V were assessed for both the ears. In both ear Absolute latency were significantly higher in diabetics as compared to non-diabetic patientsConclusion The findings of present study showed that the severity of hearing loss was significantly higher in diabetic patients as compared to non-diabetic controls. Level of glycemic control showed a possible link with severity of hearing loss.

Potentially predictive factors for hearing function improvement in pediatric cytomegalovirus infection therapy

Background Symptomatic congenital cytomegalovirus (CMV) infection has an impact mainly on neurological sequelae, including sensorineural deafness. Because of the long-term impact, early treatment of CMV infection is mandatory. However, predictive factors for hearing function improvement in CMV infection therapy remain unexamined. Objective To evaluate potential predictive factors for hearing improvement in pediatric CMV infection therapy. Methods All medical record data of patients aged 0-6 years with CMV infection who completed a 6-week course of ganciclovir therapy or a combination of a 4-week course of ganciclovir and a 2-week course valganciclovir from January 2013 to December 2017 were collected. Age at onset of therapy, gender, gestational age, nutritional status, multi-organ involvement, and neurological symptoms were studied as potential predictive factors of hearing improvement in CMV therapy. The effectiveness of CMV infection therapy on improving hearing function was measured with the brainstem evoked response audiometry (BERA) test. Results BERA tests proportion in the right, left, and best ear showed significant improvement after therapy. All variables analyzed were not statistically significant as predictive factors for hearing improvement in CMV infection therapy. Conclusion Ganciclovir/valganciclovir therapy in CMV infection patients accounted for the improvement of hearing impairment. However, none of the assessed factors were considered predictive for improving hearing function in CMV infection therapy.

Application of Evoked Response Audiometry To Schizophrenia For Specifying 40-Hz Aberrant Gamma Oscillations In A Real-World Clinical Setting

Gamma oscillations probed using auditory steady-state response (ASSR) are promising clinical biomarkers that may address novel therapeutic interventions for schizophrenia. Optimizing clinical settings for these biomarker-driven interventions will require a quick and easy assessment system of gamma oscillations in psychiatry. ASSR has been used in clinical otolaryngology for evoked response audiometry (ERA) to judge hearing loss by focusing on the phase-locked response detectability in an automated analysis system. Herein, a standard ERA system was applied to evaluate the brain pathophysiology of patients with schizophrenia with 40-Hz ASSR. The 40-Hz ASSR in the ERA system showed excellent detectability of the phase-locked response in healthy subjects, which sharply captured the deficits of the phase-locked response caused by aberrant gamma oscillations in individuals with schizophrenia. These findings reveal the availability of the ERA system in specifying patients who have aberrant 40-Hz gamma oscillations. The ERA system may have a potential to serve as a real-world clinical setting for upcoming biomarker-driven therapeutics in psychiatry.