Exploring brainstem auditory evoked potentials and mental development index as early indicators of autism spectrum disorders in high-risk infants

This study of infants from Hubei Province, China examined brainstem auditory evoked potentials (BAEP) and mental development index (MDI) as possible early indicators associated with autism spectrum disorders (ASD). The 34 ASD cases and 102 controls who had recovered from perinatal conditions were matched for age, sex, gestational age, birth weight and maternal age. BAEP absolute latencies (AL) I, III, V and interpeak latencies (IPL) I-III, III-V, I-V were compared in ASD cases and controls at ages 1, 3 and 6 months. MDI scores were compared in these infants from 1 month to 2 years old. Multiple logistic regression analysis was performed to test associations among ASD, BAEP and MDI. Results showed BAEP AL I, V and IPL III-V prolonged in the ASD group (p < 0.001), and MDI scores in ASD cases sharply declining from 12 to 24 months (p < 0.001). Regression analysis revealed odds ratios (OR) indicating that ASD was likely associated with abnormal values of BAEP AL I at 1 and 3 months (OR_{AL I} : 4.27; OR_{AL I} : 4.13), and AL V at 6 months (OR_{AL V} : 7.85). Lower MDI scores (MDI < 80) in infants at 1, 3, and 6 months were likely associated with ASD (OR_MDI : 2.58; OR_MDI : 3.83; OR_MDI : 4.87). These data show that abnormal BAEP values and low MDI scores are independent factors associated with ASD, and that monitoring of BAEP and MDI during infancy might facilitate screening for ASD development.

Clinical evaluation of acute necrotizing encephalopathy in children

OBJECTIVE

Acute necrotizing encephalopathy (ANE) is a rare but severe encephalopathy and is associated with a high morbidity and mortality. We aimed to analyze and compare the clinical features and predictive indicators of pediatric ANE.

MATERIALS AND METHODS

This retrospective study included children with ANE diagnosed at Guangzhou Women and Children's Medical Center between November 2018 and January 2020. Pediatric patients' information, including clinical characteristics, laboratory tests, neuroelectrophysiology and brain magnetic resonance imaging (MRI) findings, MRI score, brainstem auditory evoked potential (BAEP) grades, ANE severity scores (ANE-SS), and modified Rankin scale (mRS), were collected.

RESULTS

Twelve ANE patients were included. Among them, one patient (8.3%) died from brainstem dysfunction, one (8.3%) recovered and 10 (83.3%) experienced neurological sequelae. All patients had an initial viral infection and neurological symptoms such as acute disturbance of consciousness (ADOC) or seizure, and the interval from onset of the disease to neurological manifestations was 3 (1.25-3) days. MRI score-I ranged from 1 to 3 (1.8 ± 0.7), MRI score-II ranged from 1 to 4 (2.5 ± 1.1). ANE-SS varied from 1 to 6 (3.9 ± 1.3). The scores of mRS were from 0 to 6 (2.9 ± 1.7). Higher MRI score were associated with worse outcomes, while the BAEP grade and ANE-SS score were not significantly associated with mRS.

CONCLUSION

ANE is a severe encephalopathy syndrome with rapid progression, resulting in serious neurological sequelae. Compared with BAEP grade and ANE-SS, brain MRI shows more comprehensive advantages in predicting the prognosis of ANE patients. More in-depth research and better indicators are still needed to support the evaluation and treatment of ANE.

Use of the auditory brainstem response for assessment of cochlear synaptopathy in humans

Although clinical use of the auditory brainstem response (ABR) to detect retrocochlear disorders has been largely replaced by imaging in recent years, the discovery of cochlear synaptopathy has thrown this foundational measure of auditory function back into the spotlight. Whereas modern imaging now allows for the noninvasive detection of vestibular schwannomas, imaging technology is not currently capable of detecting cochlear synaptopathy, the loss of the synaptic connections between the inner hair cells and afferent auditory nerve fibers. However, animal models indicate that the amplitude of the first wave of the ABR, a far-field evoked potential generated by the synchronous firing of auditory nerve fibers, is highly correlated with synaptic integrity. This has led to many studies investigating the use of the ABR as a metric of synaptopathy in humans. However, these studies have yielded mixed results, leading to a lack of consensus about the utility of the ABR as an indicator of synaptopathy. This review summarizes the animal and human studies that have investigated the ABR as a measure of cochlear synaptic function, discusses factors that may have contributed to the mixed findings and the lessons learned, and provides recommendations for future use of this metric in the research and clinical settings.

[Association between the inter-aural latency difference of brainstem auditory evoked potential wave V and neonatal hyperbilirubinemia]

OBJECTIVE

To study brainstem auditory evoked potential (BAEP) in neonates with hyperbilirubinemia using short auditory stimuli (60 dBnHL), and to investigate the differences in the inter-aural latency difference (ILD) of wave V between neonates with different total serum bilirubin (TSB) levels.

METHODS

A prospective study was conducted in neonates with hyperbilirubinemia who were admitted to the Department of Neonatology, Yuhuan People's Hospital of Zhejiang Province, from May 2019 to October 2020. The neonates were divided into a severe group (n=50) and a mild group (n=50) according to their TSB levels. The mild group was divided into two subgroups: 7-10 days (n=20) and 11-14 days (n=20) according to their age. ILD was compared between the neonates with different TSB levels, and its diagnostic value was analyzed.

RESULTS

Compared with the mild group, the severe group had significantly higher proportions of neonates with abnormal hearing threshold and abnormal ILD (P < 0.05) and a significantly larger ILD of wave V (P < 0.05). The latency of wave V (left ear) in the 7-10 days subgroup was significantly longer than that in the 11-14 days subgroup (P < 0.05), but there was no significant difference in the ILD of wave V between the two groups (P > 0.05). The receiver operating characteristic (ROC) analysis showed that ILD had predictive value for hearing impairment caused by neonatal hyperbilirubinemia (P < 0.05), with an area under the ROC curve of 0.727 as well as a sensitivity of 52.4% and a specificity of 90.9% at the optimal cut-off value of 0.365 ms.

CONCLUSIONS

Serum bilirubin in neonates affects the ILD of BAEP wave V, especially in those with severe hyperbilirubinemia. ILD at the optimal cut-off value of ≥0.4 ms shows potential value in the diagnosis of hearing impairment caused by neonatal hyperbilirubinemia.

The Clinical Effect of Repetitive Transcranial Magnetic Stimulation on the Disturbance of Consciousness in Patients in a Vegetative State

Objective

To explore the effect of combining repetitive transcranial magnetic stimulation (rTMS) and conventional rehabilitation on the recovery of consciousness in patients in a persistent vegetative state (PVS).

Methods

A total of 48 patients in a PVS were randomly divided into a treatment and control group. Patients in the treatment group were treated with rTMS to stimulate the dorsolateral prefrontal cortex, and patients in the control group were treated with false stimulation. All patients were evaluated using scales and neuroelectrophysiological assessment before treatment, after 30 days of treatment, and following 60 days of treatment.

Results

Based on the Coma Recovery Scale-Revised (CRS-R) and electroencephalogram (EEG) grading indexes, the treatment group was significantly higher than those of the control group after 30 and 60 days of treatment. The average difference in the three measurements between the two groups before treatment, at 30 days, and 60 days was 0.04, 1.54, and 2.09 for CRS-R and 0.08, −0.83, and −0.62 for EEG indexes, respectively. The latency periods of each wave of the brainstem auditory evoked potentials (BAEPs) in the treatment group were shorter than those in the control group after 30 and 60 days of treatment. In both groups, the BAEP scores after 30 days of treatment were significantly higher than the scores before treatment, and the scores after 60 days of treatment were higher than the scores after 30 days.

Conclusion

In patients in a PVS, rTMS assists in the recovery of consciousness function.

Machine-Learning-Based Rehabilitation Prognosis Prediction in Patients with Ischemic Stroke Using Brainstem Auditory Evoked Potential

To evaluate the feasibility of brainstem auditory evoked potential (BAEP) for rehabilitation prognosis prediction in patients with ischemic stroke, 181 patients were tested using the Korean version of the modified Barthel index (K-MBI) at admission (basal K-MBI) and discharge (follow-up K-MBI). The BAEP measurements were performed within two weeks of admission on average. The criterion between favorable and unfavorable outcomes was defined as a K-MBI score of 75 at discharge, which was the boundary between moderate and mild dependence in daily living activities. The changes in the K-MBI scores (discharge-admission) were analyzed by nonlinear regression models, including the artificial neural network (ANN) and support vector machine (SVM), with the basal K-MBI score, age, and interpeak latencies (IPLs) of the BAEP (waves I, I-III, and III-V). When including the BAEP features, the correlations of the ANN and SVM regression models increased to 0.70 and 0.64, respectively. In the outcome prediction, the ANN model with the basal K-MBI score, age, and BAEP IPLs exhibited a sensitivity of 92% and specificity of 90%. Our results suggest that the BAEP IPLs used with the basal K-MBI score and age can play an adjunctive role in the prediction of patient rehabilitation prognoses.

Research on the Relationship Between Vestibular Migraine With/Without Cognitive Impairment and Brainstem Auditory Evoked Potential

Background: Vestibular migraine (VM) is the most common cause of spontaneous vertigo with no specific physical and laboratory examinations, and is an under-recognized entity with substantial burden for the individual and the society. In this study, by observing the brainstem auditory evoked potential (BAEP) and cognitive function of VM patients, the possible laboratory diagnostic indicators of VM and the influence of disease on cognitive function were discussed. Method: The study included 78 VM patients, 76 migraine patients, and 79 healthy individuals. The age, gender, and other clinical history of the three groups matched. All participants underwent BAEP examinations, in which patients in the migraine group and outpatients of the VM group were in the interictal period, and inpatients in the VM group were examined during episodes, while all patients tested for the Addenbrooke's cognitive examination-revised (ACE-R) scale were in the interictal period. The differences in BAEP and ACE-R scores between the three groups of members and their relationship with the clinical features of VM patients were analyzed. Result: The peak latency of I, III, and V wave in the BAEP of the VM group was longer than that of the migraine group and the control group (p < 0.05). The peak latency of V wave in the BAEP of the migraine group was longer than that of the control group (p < 0.05). The ACE-R of the VM group scored lower than the migraine group in terms of language fluency and language (p < 0.05), and lower than the control group in terms of total score, language fluency, language, and visuospatial (p < 0.05); and the ACE-R of the migraine group scored lower than the control group in the total score and visuospatial (p < 0.05). Conclusion: Migraine patients have brainstem dysfunction, and VM patients have more severe brainstem dysfunction than migraine patients, suggesting that VM patients have both central nervous system damage and peripheral nerve damage. Migraine patients have cognitive impairment, while cognitive impairment in VM patients is more severe than in migraine patients.

Evoked potential changes in patients with Parkinson's disease

OBJECTIVE

Patients with Parkinson's disease (PD) may have sensory dysfunction, and it can be more easily demonstrated through electrophysiologic testing. We aimed to explore whether the impairment of brainstem visual and auditory passageway exists in PD patients using visual evoked potential (VEP) and brainstem auditory evoked potential (BAEP) examinations.

METHODS

Forty-two PD cases and thirty controls participated in the study. All subjects underwent the VEP and BAEP examinations. The N75, P100, N145 latencies and P100 amplitude of VEP, the latencies of waves I, III, V and the interpeak latencies (IPL) of waves I-III, III-V, I-V were measured.

RESULTS

The N75, P100, N145 latencies of VEP, but not the amplitude of P100, were significantly longer in patients with PD than the control group (p < .05). The latencies of wave III and wave V, the IPL of III-V and I-V were all significantly increased compared with control subjects while no significant difference was noted in waves I and I-III IPL.

CONCLUSION

Our results found that brainstem visual and auditory passageway may be impaired in PD patients.

SIGNIFICANCE

VEP and BAEP can be served as sensitive measurements in helping prognosis and assessment the severity of the disease.

Transplantation of human adipose tissue-derived stem cells for repair of injured spiral ganglion neurons in deaf guinea pigs

Excessive noise, ototoxic drugs, infections, autoimmune diseases, and aging can cause loss of spiral ganglion neurons, leading to permanent sensorineural hearing loss in mammals. Stem cells have been confirmed to be able to differentiate into spiral ganglion neurons. Little has been reported on adipose tissue-derived stem cells (ADSCs) for repair of injured spiral ganglion neurons. In this study, we hypothesized that transplantation of neural induced-human ADSCs (NI-hADSCs) can repair the injured spiral ganglion neurons in guinea pigs with neomycin-induced sensorineural hearing loss. NI-hADSCs were induced with culture medium containing basic fibroblast growth factor and forskolin and then injected to the injured cochleae. Guinea pigs that received injection of Hanks’ balanced salt solution into the cochleae were used as controls. Hematoxylin-eosin staining showed that at 8 weeks after cell transplantation, the number of surviving spiral ganglion neurons in the cell transplantation group was significantly increased than that in the control group. Also at 8 weeks after cell transplantation, immunohistochemical staining showed that a greater number of NI-hADSCs in the spiral ganglions were detected in the cell transplantation group than in the control group, and these NI-hADSCs expressed neuronal markers neurofilament protein and microtubule-associated protein 2. Within 8 weeks after cell transplantation, the guinea pigs in the cell transplantation group had a gradually decreased auditory brainstem response threshold, while those in the control group had almost no response to 80 dB of clicks or pure tone burst. These findings suggest that a large amount of NI-hADSCs migrated to the spiral ganglions, survived for a period of time, repaired the injured spiral ganglion cells, and thereby contributed to the recovery of sensorineural hearing loss in guinea pigs.

[Risk factors for hearing impairment induced by cytomegalovirus infection]

OBJECTIVE

To investigate the risk factors for hearing impairment induced by cytomegalovirus (CMV) infection in children.

METHODS

One hundred and fifty-eight children diagnosed with CMV infection were enrolled as subjects. Based on the results of the brainstem auditory evoked potential (BAEP) test, patients were classified into normal hearing group (n=117; BAEP≤35) and abnormal hearing group (n=41; BAEP>35). A retrospective analysis was performed on the general information, routine blood indices, liver function, copy number of CMV-DNA in urine and breast milk. The receiver operating characteristic (ROC) curve was used to predict the copy number of CMV-DNA resulting in abnormal BAEP. The Spearman rank correlation analysis was used to test the correlations of the copy number of CMV-DNA in urine with the degree of hearing impairment and platelet count.

RESULTS

The incidence rates of platelet abnormality and abnormal liver function and the copy number of CMV-DNA in urine were significantly higher in the abnormal hearing group than in the normal hearing group (P<0.01). According to the ROC curve, the copy number of CMV-DNA in urine had a sensitivity of 46.3% and a specificity of 93.2% in predicting hearing impairment when it reached 1.415×10(6) per mL. The results of correlation analysis showed that the degree of hearing impairment was positively correlated with the copy number of CMV-DNA (r=0.382, P<0.01); the platelet count was negatively correlated with the copy number of CMV-DNA in urine (r=-0.233, P=0.003).

CONCLUSIONS

An increased copy number of CMV-DNA in urine might be a risk factor for hearing impairment induced by CMV infection. Children are likely to have hearing impairment when the copy number of CMV-DNA reaches 1.415×10(6) per mL. The monitoring of hearing should be strengthened in CMV-infected children with a decreased platelet count.

Real-time intraoperative monitoring of brainstem auditory evoked potentials during microvascular decompression for hemifacial spasm

OBJECTIVE The aim of this study was to define a new protocol for intraoperative monitoring (IOM) of brainstem auditory evoked potentials (BAEPs) during microvascular decompression (MVD) surgery to treat hemifacial spasm (HFS) and to evaluate the usefulness of this new protocol to prevent hearing impairment. METHODS To define the optimal stimulation rate, estimate the number of trials to be averaged, and identify useful warning criteria in IOM of BAEPs, the authors performed a preliminary study of 13 patients with HFS in 2010. They increased the stimulation rate from 10.1 Hz/sec to 100.1 Hz/sec by 10-Hz increments, and they elevated the average time from 100 times to 1000 times by 100-unit increments at a fixed stimulus rate of 43.9 Hz. After defining the optimal stimulation rate and the number of trials that needed to be averaged for IOM of BAEPs, they also identified the useful warning criteria for this protocol for MVD surgery. From January to December 2013, 254 patients with HFS underwent MVD surgery following the new IOM of BAEPs protocol. Pure-tone audiometry and speech discrimination scoring were performed before surgery and 1 week after surgery. To evaluate the usefulness of the new protocol, the authors compared the incidence of postoperative hearing impairment with the results from the group that underwent MVD surgery prior to the new protocol. RESULTS Through a preliminary study, the authors confirmed that it was possible to obtain a reliable wave when using a stimulation rate of 43.9 Hz/sec and averaging 400 trials. Only a Wave V amplitude loss > 50% was useful as a warning criterion when using the new protocol. A reliable BAEP could be obtained in approximately 9.1 seconds. When the new protocol was used, 2 patients (0.8%) showed no recovery of Wave V amplitude loss > 50%, and only 1 of those 2 patients (0.39%) ultimately had postoperative hearing impairment. When compared with the outcomes in the pre-protocol group, hearing impairment incidence decreased significantly among patients who underwent surgery with the new protocol (0.39% vs 4.02%, p = 0.002). There were no significant differences between the 2 surgery groups regarding other complications, including facial palsy, sixth cranial nerve palsy, and vocal cord palsy. CONCLUSIONS There was a significant decrease in postoperative hearing impairment after MVD for HFS when the new protocol for IOM of BAEPs was used. Real-time IOM of BAEPs, which can obtain a reliable BAEP in less than 10 seconds, is a successful new procedure for preventing hearing impairment during MVD surgery for HFS.

Brainstem auditory evoked potential monitoring and neuro-endoscopy: two tools to ensure hearing preservation and surgical success during microvascular decompression

BACKGROUND

The effectiveness of microvascular decompression (MVD) has made trigeminal neuralgia (TN), hemifacial spasm (HFS), glossopharyngeal neuralgia, and other cranial nerve rhizopathy diseases treatable by surgery. To ensure hearing preservation and surgical success, we have presented our experience in the application of brainstem auditory evoked potential (BAEP) monitoring and neuro-endoscopy during MVD.

METHODS

From July 2007 to October 2012, a total of 93 patients in our institution received MVD for cranial nerve rhizopathies. Among these patients, 43 had both BAEP monitoring and endoscope-assisted microsurgery for their MVD. None of the patients had undergone previous surgical treatment. Postoperative outcomes were assessed based on the medical records and clinical follow-up.

RESULTS

This study included 32 women and 11 men. There were 36 HFS cases and seven TN cases, and the median patient age at the time of MVD was 48 years. The median duration of symptoms before MVD was 4.2 years, and the median follow-up duration was 3.5 years (range 1.5 months-5 years). All of the patients had either immediate or delayed complete relief from the symptoms after MVD. One TN patient underwent gamma knife radiosurgery 3 years after MVD, and two HFS cases had recurrent slight spasms, which warranted no further treatment. There was no surgical mortality. The major complications included one HFS patient with delayed and permanent hearing loss and facial palsy, which occurred 1 week after MVD. The surgical success rate was 100%, and the hearing complication rate was 2%.

CONCLUSION

The results of this retrospective study emphasized the importance of BAEP monitoring and neuro-endoscopy during MVD. It is well known that BAEP monitoring can preserve hearing function, and the endoscope offers neurosurgeons a second look to identify the nerve root entry zone and confirms the position of the Teflon felt. These two tools are especially useful in difficult cases.