The Narrowband CE-Chirp Stimulus Does Not Necessarily Produce More Robust Cervical Vestibular Evoked Myogenic Potential.

OBJECTIVE: Various studies have been conducted to search for the most optimal stimulus for eliciting cervical vestibular evoked myogenic potential (cVEMP). More recently, there is a growing interest to study the usefulness of chirp stimuli in cVEMP recording. Nevertheless, contradictory outcomes have been reported across the studies, and further research with larger samples would be beneficial to provide better insight into this matter. As such, the present study was carried out to compare cVEMP results between narrowband (NB) CE-Chirp (centered at 500 Hz) and 500 Hz tone burst stimuli. DESIGN: In this study that employed a comparative study design, 98 normally hearing adults aged between 19 and 24 years were enrolled. All of them underwent the cVEMP testing based on the recommended test protocol. The stimuli were a 500 Hz tone burst and a NB CE-Chirp (360-720 Hz) presented through insert earphones at an intensity level of 120.5 dB peSPL. RESULTS: For each stimulus, cVEMP results did not differ significantly between the ears ( p > 0.05). Relative to the 500 Hz tone burst, the NB CE-Chirp stimulus produced statistically shorter P1 and N1 latencies ( p < 0.001). On the other hand, P1-N1 amplitude was found to be comparable between the two stimuli ( p > 0.05). CONCLUSIONS: The present study did not find any supporting evidence that the NB CE-Chirp stimulus (centered at 500 Hz) outperformed the conventional 500 Hz tone burst in the cVEMP testing. Both stimuli are considered equally appropriate to record cVEMP responses in clinical settings.

The Influence of Stimulus Repetition Rate on Tone-Evoked Post-Auricular Muscle Response (PAMR) Threshold.

OBJECTIVES: Post-auricular muscle response (PAMR) is a large myogenic potential that can be useful in estimating behavioral hearing thresholds when the recording protocol is optimal. The main aim of the present study was to determine the influence of stimulus repetition rate on PAMR threshold. DESIGN: In this repeated-measures study, 20 normally hearing adults aged between 18 and 30 years were recruited. Tone bursts (500, 1000, 2000, and 4000 Hz) were used to record PAMR thresholds at 3 different stimulus repetition rates (6.1/s, 11.1/s, and 17.1/s). RESULTS: Statistically higher PAMR thresholds were found for the faster stimulus rate (17.1/s) compared with the slower stimulus rate (6.1/s) (p < 0.05). For all stimulus rates and frequencies, significant correlations were found between PAMR and pure-tone audiometry thresholds (r = 0.62 to 0.82). CONCLUSIONS: Even though the stimulus rate effect was significant at most of the tested frequencies, the differences in PAMR thresholds between the rates were small (<5 dB). Nevertheless, based on the correlation results, we suggest the use of 11.1/s stimulus rate when recording PAMR thresholds.

The influences of age, gender and geometric pattern of visual image on the verticality perception: A subjective visual vertical (SVV) study among Malaysian adults.

OBJECTIVES: Subjective visual vertical (SVV) is a simple, quick and reliable test for measuring utricular function. The literature on the effects of fundamental demographic variables such as age and gender on SVV is inconclusive and should be supported by research with larger samples. The aim of the present study was to determine the influences of age, gender and geometric pattern of visual image on SVV among healthy adults. STUDY DESIGN: This study employed a repeated measures design. SETTINGS: Otorhinolaryngology Clinic, Hospital Universiti Sains Malaysia, Malaysia. PARTICIPANTS: Eligible Malaysian adults (N = 187, aged 21-75 years) were recruited and categorised into young (N = 60), middle-aged (N = 66) and older (N = 61) groups. Most of them were Malay, and 51.3% were men. MAIN OUTCOME MEASURES: Subjective visual vertical angles (in degrees) were determined from each participant in a static upright condition using a computerised SVV device. They were asked to indicate their verticality perception for three types of visual images (solid line, dotted line and arrow pattern). RESULTS: Three-way mixed ANOVA revealed insignificant influences of age and gender on SVV results (P > 0.05). In contrast, mean SVV angles were significantly higher for the arrow pattern than for other visual images (P = 0.004). CONCLUSION: While the insignificant influences of age and gender on static SVV are further ascertained with larger samples, the perception of verticality is less accurate when aligning a more geometrically complex visual image (ie, arrow pattern). Further SVV research on vestibular-disordered patients is beneficial, particularly to verify the normative data obtained with this complex visual image.

Are speech-evoked auditory brainstem response (speech-ABR) outcomes influenced by ethnicity?

Due to its objective nature, auditory brainstem response (ABR) evoked by complex stimuli has been gaining attention lately. The present study aimed to compare the speech-evoked auditory brainstem response (speech-ABR) results between two ethnic groups: Malay and Chinese. In addition, it was also of interest to compare the speech-ABR outcomes obtained from the present study with the published Caucasian data. Thirty healthy male adults (15 Malay and 15 Chinese) were enrolled in this comparative study. Speech syllable/da/presented at 80 dBnHL was used to record speech-ABR waveforms from the right ear of each subject. Amplitudes and latencies of speech-ABR peaks (V, A, C, D, E, F and O), as well as composite onset measures (V/A duration, V/A amplitude and V/A slope) were computed and analyzed. When the two ethnic groups were compared, all speech-ABR results were not statistically different from each other (p > 0.05). When the data from the present study were compared with the published Caucasian data, most of the statistical analyses were significant (p < 0.05). That is, Asian subjects revealed significantly higher peak amplitudes, earlier peak latencies, higher V/A amplitudes and steeper V/A slopes than that of Caucasians. The speech-ABR results between Malay and Chinese were found to be essentially similar due to anatomical similarities. Nevertheless, specific normative data for Asian adults are required as their speech-ABR results are different from that of Caucasian males. This issue should be addressed before it can be applied holistically in multiracial countries.

Gender and modulation frequency effects on auditory steady state response (ASSR) thresholds.

For estimating behavioral hearing thresholds, auditory steady state response (ASSR) can be reliably evoked by stimuli at low and high modulation frequencies (MFs). In this regard, little is known regarding ASSR thresholds evoked by stimuli at different MFs in female and male participants. In fact, recent data suggest that 40-Hz ASSR is influenced by estrogen level in females. Hence, the aim of the present study was to determine the effect of gender and MF on ASSR thresholds in young adults. Twenty-eight normally hearing participants (14 males and 14 females) were enrolled in this study. For each subject, ASSR thresholds were recorded with narrow-band chirps at 500, 1,000, 2,000, and 4,000 Hz carrier frequencies (CFs) and at 40 and 90 Hz MFs. Two-way mixed ANOVA (with gender and MF as the factors) revealed no significant interaction effect between factors at all CFs (p > 0.05). The gender effect was only significant at 500 Hz CF (p < 0.05). At 500 and 1,000 Hz CFs, mean ASSR thresholds were significantly lower at 40 Hz MF than at 90 Hz MF (p < 0.05). Interestingly, at 2,000 and 4,000 Hz CFs, mean ASSR thresholds were significantly lower at 90 Hz MF than at 40 Hz MF (p < 0.05). The lower ASSR thresholds in females might be due to hormonal influence. When recording ASSR thresholds at low MF, we suggest the use of gender-specific normative data so that more valid comparisons can be made, particularly at 500 Hz CF.

A meta-analysis comparing the performance of narrowband CE-Chirp and 500 Hz tone burst stimuli in recording cervical vestibular evoked myogenic potential (cVEMP).

Due to contradictory outcomes in the literature, the aim of this meta-analysis is to verify whether the narrowband (NB) CE-Chirp stimulus (centred at 500 Hz) would produce more robust cervical vestibular evoked myogenic potential (cVEMP) responses relative to the conventional 500 Hz tone burst. The literature search was conducted using PubMed, Scopus, and Web of Science databases and the terms used were "vestibular evoked myogenic potential" and "chirp". The cVEMP parameters to be analysed were P1 latency, N1 latency, and P1-N1 amplitude. A total of 59 potential articles were obtained from the database search. Eventually, five articles were found to be eligible for the meta-analysis (with n = 222). As found, P1 and N1 latencies of cVEMP were significantly shorter for the chirp stimulus (p < 0.001), with substantially large effect sizes. On the other hand, P1-N1 amplitude values were found to be not statistically different between the two stimuli (p = 0.189), with a small effect size. It appears that there is no indication to support the superiority of the NB CE-Chirp stimulus (centred at 500 Hz) in the cVEMP testing (relative to the conventional 500 Hz tone burst). In particular, both stimuli produce comparable P1-N1 amplitude values. Even though P1 and N1 latencies are statistically shorter for the chirp stimulus, this may not reflect that it should be the preferred stimulus for recording cVEMP responses (and the reasons for this are discussed accordingly).

Cervical vestibular evoked myogenic potential (cVEMP) findings in adults with sensorineural hearing loss (SNHL): comparisons between 500 Hz tone burst and narrowband CE-Chirp stimuli.

There has been a growing interest in studying the usefulness of chirp stimuli in recording cervical vestibular evoked myogenic potential (cVEMP) waveforms. Nevertheless, the study outcomes are debatable and require verification. In view of this, the aim of the present study was to compare cVEMP results when elicited by 500 Hz tone burst and narrowband (NB) CE-Chirp stimuli in adults with sensorineural hearing loss (SNHL). Fifty adults with bilateral SNHL (aged 20-65 years) underwent the cVEMP testing based on the established protocol. The 500 Hz tone burst and NB CE-Chirp (centred at 500 Hz) stimuli were presented to each ear at an intensity level of 120.5 dB peSPL. P1 latency, N1 latency, and P1-N1 amplitude values were analysed accordingly. The NB CE-Chirp stimulus produced significantly shorter P1 and N1 latencies (p < 0.001) with large effect sizes (d > 0.80). In contrast, both stimuli elicited cVEMP responses with P1-N1 amplitude values that were not statistically different from one another (p = 0.157, d = 0.15). Additionally, age and hearing level were found to be significantly correlated (r = 0.56, p < 0.001), as were age and cVEMP amplitude for each stimulus (p < 0.001). To conclude, since both stimuli were presented at an equivalent intensity level (in dB peSPL), the shorter P1 and N1 latencies of cVEMP produced by the NB CE-Chirp stimulus (centred at 500 Hz) were unlikely due to enhanced saccular stimulation. Another more sensible reason is the temporal adjustment of the chirp stimulus.

Clinical use of Malay Version of Vertigo Symptom Scale (MWSS) in patients with peripheral vestibular disorder (PVD).

INTRODUCTION: The Vertigo symptom scale (VSS) is a well established tool for the evaluation of vestibular disorders and the associated symptoms of autonomic arousal and somatosensation. By using a validated Malay version of vertigo symptom scale (MVVSS) questionnaire, the severity of the vertigo from patients' perspective can be determined and rated. Before MVVSS can be applied clinically among Malaysians, it was of interest to determine its clinical value in identifying vestibular disorders. METHOD: Forty normal and 65 PVD subjects participated in this cross-sectional study. Normal subjects were recruited amongst Universiti Sains Malaysia (USM) staff and students who had no history of ear and vestibular disorders. RESULTS: Mean total score of MVVSS in normal and PVD subjects were 13.9 +/- 11.1 and 30.1 +/- 20.9, respectively. When the total scores of normal and PVD group were compared, the Mann-Whitney U test showed that there was a significant difference between the two groups (p < 0.05). This is consistent with previous studies. It was also of interest to see if subtypes of PVD [benign paroxymal positional vertigo (BPPV), Meniere's disease, labyrinthitis and unknown] have different MVVSS results. However, analysis of variance (ANOVA) found no significant difference in term of outcomes of MVVSS among the different PVD pathologies. Using receiver operating characteristic curve (ROC) method, the sensitivity and specificity of MVVSS were 71% and 60%, respectively. CONCLUSION: MVVSS is able to discriminate clinically among the normal and PVD subjects. However, it is not a good indicator for differential diagnosis of PVD subtypes, at least in this study. Its sensitivity and specificity in clinical diagnosis are reasonably high. Perhaps a bigger sample size would be useful to further study the clinical usefulness of MVVSS.

Cross-cultural Adaptation of the Consensus Auditory-perceptual Evaluation of Voice (CAPE-V) Into Malay: A Validity Study.

Auditory-perceptual rating of voice is one component of voice evaluation, and the CAPE-V is one of the tools for this purpose. Because of its advantages, the CAPE-V has been adapted into several languages. Accordingly, the adaptation of the CAPE-V into Malay is essential for its utility among the Malaysian population, which this study aimed to accomplish. This study involved translating the CAPE-V into Malay, termed the Malay CAPE-V, followed by establishing its validity. The translation processes (ie, forward translation and backward translation) involved four different translators ie, three speech-language therapists (SLTs), and one linguist with at least 14 years of experience. Most items were similarly translated, except for a few, which were subsequently accepted as similar, following consensus among the translators. In the examination of content validity, two raters (ie, SLTs) with at least 12 years of clinical experience reviewed and scored the tested items. Given that the scale-level content validity index average value (S-CVI/Ave) was above the acceptable level, all items were retained. The examination of construct validity and concurrent validity involved ratings of voice samples recorded from 38 participants, comprising 19 individuals with normal and disordered voices, respectively. The ratings were performed by three raters (ie, SLTs) with at least 12 years of clinical experience. For the construct validity, the Mann-Whitney U test indicated significantly higher scores of the vocal parameters of the Malay CAPE-V for the disordered voice group than for the normal voice group. Meanwhile, for the concurrent validity, the Spearman correlation indicated that all relationships between the scores of the vocal parameters of the Malay CAPE-V and GRBAS Scale were significant, with most of them achieving a very strong positive correlation. The results demonstrated that the Malay CAPE-V is a valid tool for an auditory-perceptual rating of voice among the Malaysian population.

Comparing the diagnostic accuracy of audiometric Weber test and tuning fork Weber test in patients with conductive hearing loss.

Objectives: Weber test is typically conducted using tuning forks, but an audiometer can also be used for a similar purpose. Compared to the tuning fork Weber (TFW) test, performing the audiometric Weber (AW) test offers many advantages. Nevertheless, AW and TFW tests' performance compared to pure-tone audiometry (PTA) has yet to be studied. The present study aimed to determine the accuracy and agreement between the AW and TFW tests compared to PTA. Methods: In this observational cross-sectional study, 74 participants (aged 12-67 years) with unilateral conductive hearing loss (CHL) or bilateral asymmetrical CHL were enrolled. The TFW test was performed according to the established protocol at 256 and 512 Hz. For the AW test, the bone vibrator was placed in the middle of the forehead, where 250 and 500 Hz frequencies were tested. TF and AW test results were then compared with the expected lateralization from the respective PTA results. Results: At 256 Hz (or 250 Hz), the overall accuracy values of TFW and AW tests were 81.1% and 86.5%, respectively. At 512 Hz (or 500 Hz), the overall accuracy results of TFW and AW tests were 85.1% and 82.4%, respectively. In addition, the kappa statistics revealed substantial agreements between the two tests and PTA (k = .63-.72). Conclusion: Both AW and TFW tests are reasonably accurate in assessing patients with CHL. It is recommended for audiologists to perform the simple AW test to verify incomplete or questionable audiograms that are commonly encountered in clinical practice. Level of evidence: Level 3b.

Effects of Ambient Acoustic Noise on Auditory Brainstem Response to Level-Specific Chirp and Click Stimuli in Normal-Hearing Adults.

BACKGROUND AND OBJECTIVES: Despite few reports on the influence of ambient acoustic noise on auditory brainstem response (ABR) to click stimuli, its effects on ABR to level-specific (LS) stimuli have not been systematically investigated. This study aimed to investigate the influence of ambient acoustic noise on ABR findings using both LS chirp and click stimuli. SUBJECTS AND METHODS: Twelve normal-hearing adults participated in this repeated measure design study. The ABRs were acquired at 80, 50, and 30 dBnHL using two stimuli (LS chirp and click) under two conditions (quiet and noise). The ABRs under noise conditions were acquired using babble noise and white noise. The noise level was set at 55 dBA. Two-way repeated measure analysis was used to identify the main effects of the test conditions, stimulus types, and their interactions at a 95% confidence level. RESULTS: No significant influence of ambient acoustic noise on ABR findings was identified at all intensity levels. No significant difference was found in the number of signal averages to reach the 0.04 µV residual noise as stopping criteria among the ABRs recorded with different types of stimuli and test conditions. The ABR waves I and V amplitudes were larger with LS chirp than with click stimulus. CONCLUSIONS: Ambient acoustic noise has no significant influence on ABR findings and the ABR test time based on the 55 dBA noise level used in this study.

Quality of life in stroke patients with dysphagia: a systematic review.

INTRODUCTION: Dysphagia is a common disorder among stroke patients. Dysphagia can lead to consequences that can negatively impact the quality of life (QoL) in stroke patients. AIM: To investigate the impact of dysphagia on the QoL in stroke patients. METHODS: Relevant types of literature were searched from PubMed, Scopus, ProQuest, and Google Scholar databases from inception to July 2022. Peerreviewed studies that aimed to determine the impact of dysphagia on the QoL in stroke patients were included regardless of the year of publication. The National Institutes of Health tool for observational cohort and cross-sectional studies was used to assess the methodological quality of the selected studies. In addition, data analysis was conducted using qualitative methodology with narrative synthesis. RESULTS: A total of 6 studies met the inclusion criteria with a total number of 381 participants. Only one study has good methodological quality while other studies have fair methodological quality. Dysphagia negatively impacts the QoL in stroke patients, especially those with severe dysphagia. However, after treatment, changes were evident through improved QoL and decreased severity of dysphagia. Moreover, the research found that patients with a higher educational level have a better QoL. CONCLUSION: Dysphagia has a negative impact on the QoL in stroke patients, so dysphagia in stroke patients should be diagnosed and treated as soon as possible to avoid poor QoL.

Does the location of electrode on tympanic membrane matter when recording electrocochleography?

BACKGROUND: The non-invasive tympanic electrocochleography (TM-ECochG) is useful for clinical diagnoses. Nevertheless, the influence of the electrode location on tympanic membrane (TM) on ECochG results needs to be studied. OBJECTIVE: The aim of the present study was to compare the TM-ECochG results obtained when the electrode was placed on the superior region versus the inferior region of TM. MATERIALS AND METHODS: Forty healthy adults (aged 29 to 50 years) participated in this comparative study. The TM-ECochG testing was conducted with the electrode placed on the superior and inferior regions of TM. RESULTS: SP and AP amplitudes were statistically higher for the inferior region of TM (p < .05). In contrast, SP/AP ratios were comparable between the two regions of TM (p = .417). CONCLUSIONS AND SIGNIFICANCE: In TM-ECochG recording, when the electrode was placed on the inferior region of TM, SP and AP amplitudes were greater than when the electrode was placed on the superior region of TM. On the other hand, SP/AP amplitude ratio was not affected by the location of electrode on TM. The findings from the present study could be useful to guide clinicians in optimizing TM-ECochG recording when testing their respective patients.

Influence of Stimulus Polarity on the Auditory Brainstem Response From Level-Specific Chirp.

BACKGROUND AND OBJECTIVES: No known studies have investigated the influence of stimulus polarity on the Auditory Brainstem Response (ABR) elicited from level-specific (LS) chirp. This study is important as it provides a better understanding of the stimulus polarity selection for ABR elicited from LS chirp stimulus. We explored the influence of stimulus polarity on the ABR from LS chirp compared to the ABR from click at 80 dBnHL in normal-hearing adults. SUBJECTS AND PURPOSE: Nineteen adults with normal hearing participated. The ABRs were acquired using click and LS chirp stimuli using three stimulus polarities (rarefaction, condensation, and alternating) at 80 dBnHL. The ABRs were tested only on the right ear at a stimulus rate of 33.33 Hz. The ABR test was stopped when the recording reached the residual noise level of 0.04 µV. The ABRs amplitudes, absolute latencies, inter-peak latencies (IPLs), and the recorded number of averages were statistically compared among ABRs at different stimulus polarities and stimuli combinations. RESULTS: Rarefaction polarity had the largest ABR amplitudes and SNRs compared with other stimulus polarities in both stimuli. There were marginal differences in the absolute latencies and IPLs among stimulus polarities. No significant difference in the number of averages required to reach the stopping criteria was found. CONCLUSIONS: Stimulus polarities have a significant influence on the ABR to LS chirp. Rarefaction polarity is recommended for clinical use because of its larger ABR peak I, III, and V amplitudes than those of the other stimulus polarities.

The influence of type of visual image and gender on the perception of horizontality: a subjective visual horizontal (SVH) study.

BACKGROUND: The graviceptive otolith function can be measured using subjective visual horizontal (SVH) testing. Nevertheless, more research efforts are required to understand the essential variables affecting SVH. OBJECTIVE: The aim of the present study was to determine the effects of type of visual image and gender on subjective visual horizontal (SVH) perception among healthy adults. MATERIALS AND METHODS: In this comparative study, 50 healthy young adults were enrolled. While in an upright body position, they were required to report their perception of horizontality for two types of visual images (solid line and arrow pattern) using a computerized SVH device. RESULTS: The arrow pattern produced significantly bigger SVH angles than the solid line (p < .001). In contrast, no significant influence of gender was found on SVH results (p = .743), Based on the statistical outcomes, the preliminary normative data for SVH were established. CONCLUSIONS AND SIGNIFICANCE: The arrow pattern (a more complex visual image) produced bigger SVH deviations than the simple solid line image. In contrast, the horizontality perception does not appear to be affected by gender. The preliminary normative SVH data gathered from the present study can be beneficial for clinical and future research applications.

The effects of gender and academic achievement on reading fluency among Year 2 Malaysian school children.

OBJECTIVE: Language disorders can affect reading skills contributing to poor academic achievements. As such, it is vital for speech language pathologists to identify the potential language-based reading problems among children. To achieve this, specific reading assessments should be developed and studied. Thus, the present study aimed to determine the effects of gender and academic achievement on oral reading fluency (ORF) and silent reading fluency (SRF) among Year 2 Malaysian children. METHODS: In this study that employed a comparative design, fifty-nine typically developing Malaysian children (24 boys, aged from 8 years, 0 months to 8 years, 11 months) were enrolled. They were chosen from three different classrooms (consisting of high achieving, medium achieving and low achieving students, respectively) in a primary school. Their ORF and SRF skills were assessed according to the established methods. RESULTS: As revealed by two-way ANOVA results, both ORF and SRF scores were found to be comparable between boys and girls (p > 0.05). In contrast, ORF and SRF results between the three classrooms were significantly different from each other (p < 0.05). CONCLUSION: The present study provides the first report on oral and silent reading fluency skills among Year 2 Malaysian school children. While the gender effect was insignificant, low achieving students showed poorer reading fluency skills. The preliminary normative data for ORF and SRF provided by the present study are beneficial for future research applications.

Effects of Age and Type of Stimulus on the Cortical Auditory Evoked Potential in Healthy Malaysian Children.

BACKGROUND AND OBJECTIVES: The cortical auditory evoked potential (CAEP) is a useful objective test for diagnosing hearing loss and auditory disorders. Prior to its clinical applications in the pediatric population, the possible influences of fundamental variables on the CAEP should be studied. The aim of the present study was to determine the effects of age and type of stimulus on the CAEP waveforms. SUBJECTS AND METHODS: Thirty-five healthy Malaysian children aged 4 to 12 years participated in this repeated-measures study. The CAEP waveforms were recorded from each child using a 1 kHz tone burst and the speech syllable /ba/. Latencies and amplitudes of P1, N1, and P2 peaks were analyzed accordingly. RESULTS: Significant negative correlations were found between age and speech-evoked CAEP latency for each peak (p< 0.05). However, no significant correlations were found between age and tone-evoked CAEP amplitudes and latencies (p>0.05). The speech syllable /ba/ produced a higher mean P1 amplitude than the 1 kHz tone burst (p=0.001). CONCLUSIONS: The CAEP latencies recorded with the speech syllable became shorter with age. While both tone-burst and speech stimuli were appropriate for recording the CAEP, significantly bigger amplitudes were found in speech-evoked CAEP. The preliminary normative CAEP data provided in the present study may be beneficial for clinical and research applications in Malaysian children.