scholarly journals Brainstem auditory evoked potentials in horses

2016 ◽  
Vol 46 (4) ◽  
pp. 681-685
Author(s):  
Juliana Almeida Nogueira da Gama ◽  
Mariana Isa Poci Palumbo ◽  
Giovane Olivo ◽  
Nadia Crosignani Outeda ◽  
Luiz Antônio de Lima Resende ◽  
...  

ABSTRACT: The brainstem auditory evoked potential (BAEP) evaluates the integrity of the auditory pathways to the brainstem. The aim of this study was to evoke BAEPs in 21 clinically normal horses. The animals were sedated with detomidine hydrochloride (0.013mg.kg-1 BW). Earphones were inserted and rarefaction clicks at 90 dB and noise masking at 40 dB were used. After performing the test, the latencies of waves (I, II, III, IV, and V) and interpeaks(I-III, III-V, and I-V) were identified. The mean latencies of the waves were as follows: wave I, 2.4 ms; wave II, 2.24 ms; wave III, 3.61ms; wave IV, 4.61ms; and wave V, 5.49ms. The mean latencies of the interpeaks were as follows: I-III, 1.37ms; III-V, 1.88ms; and I-V, 3.26ms. This is the first study using BAEPs in horses in Brazil, and the observed latencies will be used as normative data for the interpretation of tests performed on horses with changes related to auditory system or neurologic abnormalities.

2006 ◽  
Vol 64 (3a) ◽  
pp. 619-623 ◽  
Author(s):  
Paulo Sergio A. Henriques Filho ◽  
Riccardo Pratesi

OBJECTIVE: To evaluate the frequency and degree of severity of abnormalities in the auditory pathways in patients with Chiari malformations type I and II. METHOD: This is a series-of-case descriptive study in which the possible presence of auditory pathways abnormalities in 75 patients (48 children and 27 adults) with Chiari malformation types I and II were analyzed by means of auditory evoked potentials evaluation. The analysis was based on the determination of intervals among potentials peak values, absolute latency and amplitude ratio among potentials V and I. RESULTS: Among the 75 patients studied, 27 (36%) disclosed Arnold-Chiari malformations type I and 48 (64%) showed Arnold-Chiari malformations type II. Fifty-three (71%) of these patients showed some degree of auditory evoked potential abnormalities. Tests were normal in the remaining 22 (29%) patients. CONCLUSION: Auditory evoked potentials testing can be considered a valuable instrument for diagnosis and evaluation of brain stem functional abnormalities in patients with Arnold-Chiari malformations type I and II. The determination of the presence and degree of severity of these abnormalities can be contributory to the prevention of further handicaps in these patients either through physical therapy or by means of precocious corrective surgical intervention.


2021 ◽  
Vol 11 (3) ◽  
pp. 350
Author(s):  
Marta Waliszewska-Prosół ◽  
Maria Ejma ◽  
Paweł Gać ◽  
Anna Szymańska-Chabowska ◽  
Magdalena Koszewicz ◽  
...  

The aim of this study was to evaluate the parameters of visual and brainstem auditory evoked potentials in patients occupationally exposed to arsenic, cadmium and lead. The study group comprised 41 copper smelter and refinery workers (average age: 51.27) with occupational exposure to arsenic, cadmium and lead. The control group consisted of 36 healthy volunteers (35 men and 1 woman, aged 27–66, average age: 51.08). Neurological examination, brain imaging, and visual and brainstem auditory evoked potentials were performed, and the relationship between blood Cd, Pb concentration (Cd-B, Pb-B), blood zinc protoporphyrin (ZnPP), and urine As concentration (As-U) were assessed. In the workers, exceedances of allowable biological concentrations were observed, with the urinary concentration of arsenic being 5.2%, the cadmium and lead in blood being 1.3%, while the case of ZnPP was 2.6%. The mean P100, relative P100, and N145 visual evoked potential (VEP) latencies were significantly longer in exposed workers than in the controls. The mean wave III and V brainstem auditory evoked potential (BAEP) latency and the mean wave III–V and I–V interpeak latencies were longer, and the I and V amplitude was lower in the workers than the controls. In summary, occupational exposure to As, Cd, and Pb is associated with prolonged latency and reduced evoked potential amplitude, but As-U, Pb-B, Cd-B, and ZnPP concentrations are not linearly related to potential components. The analysis of evoked potentials may be a useful method of assessment of the central nervous system in patients with occupational exposure to heavy metals.


2014 ◽  
Vol 34 (10) ◽  
pp. 1007-1010 ◽  
Author(s):  
Mariana Isa Poci Palumbo ◽  
Luiz Antonio de Lima Resende ◽  
José Carlos de Figueiredo Pantoja ◽  
Ian G. Mayhew ◽  
Alexandre Secorun Borges

Brainstem auditory-evoked potential (BAEP) has been widely used for different purposes in veterinary practice and is commonly used to identify inherited deafness and presbycusis. In this study, 43 Boxer dogs were evaluated using the BAEP. Deafness was diagnosed in 3 dogs (2 bilateral and 1 unilateral) allowing the remaining 40 Boxers to be included for normative data analysis including an evaluation on the influence of age on the BAEP. The animals were divided into 2 groups of 20 Boxers each based on age. The mean age was 4.54 years (range, 1-8) in group I, and 9.83 years (range, 8.5-12) in group II. The mean latency for I, III, and V waves were 1.14 (±0.07), 2.64 (±0.11), and 3.48 (±0.10) ms in group I, and 1.20 (±0.12), 2.73 (±0.15), and 3.58 (±0.22) ms in group II, respectively. The mean inter-peak latencies for the I-III, III-V and I-V intervals were 1.50 (±0.15), 0.84 (±0.15), and 2.34 (±0.11) ms in group I, and 1.53 (±0.16), 0.85 (±0.15), and 2.38 (±0.19) ms in group II, respectively. Latencies of waves I and III were significant different between group I and II. For the I-III, III-V and I-V intervals, no significant differences were observed between the 2 groups. As far as we know, this is the first normative study of BAEP obtained from Boxer dogs.


1992 ◽  
Vol 35 (1) ◽  
pp. 157-166 ◽  
Author(s):  
Mark E. Chertoff ◽  
Kurt E. Hecox ◽  
Robert Goldstein

The purpose of this investigation was to describe the properties of averaged auditory evoked potential distortion products (AEP-DPs) in guinea pigs. This study provided a step toward developing a clinical index of nonlinear processing of auditory signals and supplied a baseline for studies evaluating the effect of cochlear damage on AEP-DPs. The amplitude of the AEP-DPs was evaluated as a function of f2/fl ratio (1.12–1.52) and primary frequency (500 Hz–2000 Hz). The amplitude of the AEP cubic difference tone (AEP-CDT) increased with increasing f2/fl ratio for the 500-Hz f1 primary and remained constant for the 800-Hz and 1700-Hz f1 primaries. The AEP-CDT generated by the 1100-Hz and 1400 Hz f1 primaries was maximum for the middle f2/fl ratios (1.22, 1.32, and 1.42). The AEP-CDT could not be distinguished from the noise floor for the 2000-Hz f1 primary. The AEP difference tone (AEP-DT) was larger and more frequently identified than the AEP-CDT. The amplitude of the AEP-DT decreased with an increase in f2/f1 ratio. The decrease was more pronounced for low-frequency f1 primaries than for high-frequency f1 primaries.


Author(s):  
Abeer J. Hani ◽  
Aatif M. Husain

Auditory evoked potentials (AEP) are used to evaluate the auditory pathways. Clinically the most useful AEPs are short-latency AEP, also known as brainstem auditory evoked potentials (BAEPs). As their name implies, BAEPs are used to assess the auditory pathways in the brainstem. This chapter focuses on BAEPs. The basic neuroanatomy of the generators of the BAEP waveforms is reviewed, followed by a detailed description of the techniques used to obtain BAEP and factors that may impact the results. A description of the interpretation and applications of BAEPs is provided with discussion of the significance of the changes in amplitude, absolute latencies, and interpeak latencies of the BAEP waveforms. An overview of other auditory evoked potentials is also provided.


1985 ◽  
Vol 43 (4) ◽  
pp. 347-354 ◽  
Author(s):  
C. Collin ◽  
F. Lolas

Starting off from the notion that the cerebral hemispheres differ in their processing mode, this paper reports on stimulus intensity modulation of auditory evoked potentials recorded from hemispheric leads (C3 and C4 referenced to ipsilateral mastoid processes) in a sample of 40 male Ss between 18 to 40 years of age. The experimental set up involved the recording of series of 100 trials to binaural clicks of 63.5, 74.6 and 85dB AL. Ss who were augmenters at the vertex showed positive Amplitude-Intensity function slopes over the left hemisphere; when Ss were Reducers at the vertex, the slopes were negative on the right hemisphere. These results are interpreted in terms of attention deployment or allocation to one or the other hemispheric processing mode. This might constitute a trait-like enduring subject characteristic whose relation to traditional psychometric variables needs further exploration. The modality especificity of this phenomenon is also discussed.


1997 ◽  
Vol 86 (6) ◽  
pp. 1057-1062 ◽  
Author(s):  
Cordula Matthies ◽  
Madjid Samii

✓ The usefulness of intraoperative monitoring in cerebellopontine angle surgery should be improved by obtaining faster and stronger brainstem auditory evoked potential (BAEP) responses. A new technique of direct recording at the brainstem has been developed, which is applicable to all tumor sizes. By placing a retractor with electrodes attached to its tip at the cerebellomedullary junction, the authors have recorded BAEP amplitudes that are 10 times greater than those recorded using the conventional technique. Only small sampling numbers (64–256 recordings) are required and are obtained in 5 to 15 seconds. The technique has been applied successfully in 34 patients who underwent vestibular schwannoma resections. It has also been tested in patients with intrameatal—extrameatal meningiomas and in those with vascular compressive disorders; there have been no false results. The advantages of this new technique are: 1) identification of BAEP components is easier and faster; 2) reliable BAEP responses are obtained in some cases in which conventional BAEP responses are lost or severely deformed; and 3) BAEP response deterioration and improvement are recognized earlier than would occur using the conventional technique. This last advantage provides the surgeon with a useful warning at a stage of surgery at which BAEP changes are still temporary and can be reversed. This method is different from other trials of intradural BAEP recordings in three respects: its use is not limited to particular tumor sizes; there is no interference with the surgical process; and, most important, the obtained responses correlate well with those of conventional BAEP responses, probably because the recording site is in the vicinity of the anterior cochlear nucleus. In conclusion, the chances of useful monitoring feedback with adequate adaptation of the microsurgical strategy are improved considerably.


2017 ◽  
Vol 22 (04) ◽  
pp. 460-468 ◽  
Author(s):  
Luísa Gabriel ◽  
Luíza Vernier ◽  
Maria Ferreira ◽  
Adriana Silveira ◽  
Márcia Machado

Introduction Studies using the Brainstem Auditory Evoked Potential with speech stimulus are increasing in Brazil, and there are divergences between the methodologies used for testing. Objectives To analyze the parameters used in the study of the Brainstem Auditory Evoked Potentials with speech stimulus. Data Synthesis The survey was performed using electronic databases. The search strategy was as follows: “Evoked potentials, auditory” OR “Brain stem” OR “Evoked potentials, auditory, brain stem” AND “Speech.” The survey was performed from June to July of 2016. The criteria used for including articles in this study were: being written in Portuguese, English or Spanish; presenting the description of the testing parameters and the description of the sample. In the databases selected, 2,384 articles were found, and 43 articles met all of the inclusion criteria. The predominance of the following parameters was observed to achieve the potential during study: stimulation with the syllable /da/; monaural presentation with greater use of the right ear; intensity of 80 dB SPL; vertical placement of electrodes; use of in-ear headphones; patient seated, distracted in awake state; alternating polarity; use of speech synthesizer software for the elaboration of stimuli; presentation rate of 10.9/s; and sampling rate of 20 kHz. Conclusions The theme addressed in this systematic review is relatively recent. However, the results are significant enough to encourage the use of the procedure in clinical practice and advise clinicians about the most used procedures in each parameter.


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