Do otosclerosis and stapedotomy affect semicircular canal functions? Preliminary results of video head impulse test.

BACKGROUND: Otosclerosis and stapedotomy have some effects on the vestibular system, but there are very limited data on their effects on semicircular canals (SCCs). OBJECTIVE: The aim of the study is to investigate if otosclerosis and stapedotomy have an effect on SCCs and video head impulse test (vHIT). MATERIAL AND METHODS: This retrospective study included 11 otosclerosis patients who had undergone stapedotomy and 30 healthy participants. Twenty-two ears of 11 patients with otosclerosis were divided into two groups based on whether the ear had been operated (12 ears) or not (10 ears). All participants underwent vHIT. We compared gains of all SCCs, presence of saccades among the operated ears, unoperated ears and control ears. RESULTS: Significant difference (p<.05) was noted in comparisons of gain of lateral SCCs among all groups. Control group had the highest gain, followed by unoperated and operated groups, respectively. Comparison of incidence of covert saccade showed significant difference (p<.05) for lateral and posterior SCCs. CONCLUSIONS AND SIGNIFICANCE: Otosclerosis and otosclerosis surgery may have some effects on SCC functions and thereby vHIT. Lateral SCC is the most affected SCC in terms of gain. These findings appear to add important contributions to our knowledge.

Does tympanic membrane perforation have a protective effect on the inner ear in blast-injured patients?

BACKGROUND: Blast-induced hearing loss is an acoustic trauma commonly caused by high-energy explosions of improvised explosive devices, and the auditory system may be affected by blast damage. This study aims to evaluate the protective effect of tympanic membrane perforation (TMP) on the inner ear against blast injury. METHODS: In this study, 43 adult patients who had suffered blast injury were divided into three subgroups: intact tympanic membranes in both ears, unilateral TMP, and bilateral TMP. Each patient underwent a comprehensive audiogram, including bone conduction, in the audiology department. RESULTS: Evaluation was performed on 43 (100%) males with a mean age of 31.44±8.01 years (range, 18-52 years). When the type of hearing loss was evaluated separately for each ear, sensorineural hearing loss (SNHL) was observed in 31 (36%), high-frequency SNHL in 26 (30.2%), conductive hearing loss in eight (9.3%), and mixed type hearing loss in 21 (24.4%) ears. TMP was detected in 21 (48.8%) of 43 blast-injured patients, on the right side in four (9.3%) patients, on the left side in seven (16.3%), and bilateral in 10 (23.3%). When the type of acoustic trauma was evaluated, 15 (34.9%) patients were observed to have suffered from the explosion of an IED, 12 (30.2%) from weapon explosion, six (14%) were a vehicle bomb explosion, three (7%) were projectile missile explosion, three (7%) were mortar explosion, two (4.7%) were mine explosion, and two (4.7%) were exposed to the explosion in an armored vehicle (Table 1). CONCLUSION: No significant difference was observed in the majority of the frequencies whether the tympanic membrane was perforated or not in the blast-injured patients and it was concluded that tympanic membrane perforation caused by blast injury had no protective effect on the inner ear.

Can Narrow Band Chirp Stimulus Shake the Throne of 500 Hz Tone Burst Stimulus for Cervical Vestibular Myogenic Potentials?

BACKGROUND AND OBJECTIVES: The aim of the study was to compare effects of tone-burst (TB) and narrow-band (NB) Claus Elberling (CE)-chirp stimuli on amplitude, latency and interaural asymmetry ratio (IAR) of cervical vestibular evoked myogenic potentials (cVEMP) in healthy individuals. SUBJECTS AND METHODS: The study included 50 healthy volunteers. cVEMP procedure was carried out using 500 Hz TB and NB-CE-chirp stimulus (360-720 Hz, up-chirp) in random order. cVEMP were recorded at 100 dB nHL. For each ear and each stimulus, P1 latency, N1 latency and P1N1 amplitude were measured. IAR was also calculated. RESULTS: Mean age was 26.66±9.48 years. cVEMP's in response to both TB and NB CE-chirp stimuli were obtained in all subjects. No statistically significant difference in P1 latency, N1 latency, and P1N1 amplitude was found between the right and left ears for both TB and NB CE-chirp stimuli (p>0.05). In both sides, P1 and N1 latencies were significantly shorter in NB CE-chirp stimulation compared to TB stimulation (p=0.000). In both sides, no statistically significant difference was found in P1N1 amplitude between two types of stimuli (p>0.05). CONCLUSIONS: The chirp stimulus produces robust but earlier cVEMP than TB does. This largest series study on NB chirp cVEMP shows that NB chirp is a good and new reliable alternative.

Differences in bone conduction ocular vestibular evoked myogenic potentials to 500 Hz narrow band chirp stimulus and 500 Hz tone burst.

OBJECTIVE: This study aims to investigate the differences of N1 latency, P1 latency and N1P1 amplitude in response to bone conducted 500 Hz tone burst and narrowband CE chirp stimulus in ocular vestibular evoked myogenic potentials (oVEMPs). METHODS: Forty-two healthy volunteers were included in this prospective study. Subjects with abnormal otological examinations and otological diseases were excluded. oVEMPs were randomly recorded in response to BC 500 Hz narrowband (NB) chirp stimulus and BC 500 Hz tone burst. The stimulus intensity was 50 dB nHL for both 500 Hz tone burst and 500 Hz NB CE chirp stimulus. P1 latency, N1 latency, and N1P1 amplitude were measured, and these measurements were compared between these two types of stimuli. RESULTS: Both types of stimuli elicited oVEMP in all subjects. N1 latency and P1 latency were significantly shorter (6.41 ms vs 10.84 ms; 10.64 ms vs 15.56 ms, respectively) for chirp stimulus (p < 0.05). N1P1 amplitude was significantly higher (11.64 vs 7.18 µV) for NB chirp stimulus (p < 0.05). CONCLUSION: It is reasonable to conclude that the NB CE chirp stimulus is effective to elicit robust BC oVEMP in healthy subjects.

Routine Vestibular Tests May Point Out Vestibular Subtype of Seasickness Only.

BACKGROUND: The vestibular system is important in the pathogenesis of seasickness. Our objective is to investigate whether routine vestibular tests detect seasickness.METHODS: Included were 17 professional naval personnel (mean age of 29.76 4.73 yr) diagnosed as having seasickness and 29 healthy age- and gender-matched controls. Cervical (c) vestibular evoked myogenic potentials (VEMP) and ocular (o) VEMP and bithermal caloric tests were performed after ear, nose, and throat examination, pure tone audiometry, and magnetic resonance imaging. Severity of seasickness was evaluated based on the Graybiel scale. P1 latency, N1 latency, P1N1 amplitude, and interaural asymmetry ratios (IAR) of cVEMP and oVEMP were compared between the patients and control groups. Abnormal findings in the caloric test were noted. Presence of an abnormality in any of the three vestibular tests (cVEMP, oVEMP, or caloric test) was accepted as a positive vestibular finding.RESULTS: According to the Graybiel Scale, severe malaise and frank sickness were observed in 3 patients (18.7%) and 13 patients (81.3%), respectively. Graybiel scoring could not be performed in one patient due to general discomfort and bad general condition. In the caloric test, each of three patients (17.65%) showed canal paresis, an incomplete test because of severe nausea, and vomiting and hyperactive response. There were no significant differences in P1 latency, N1 latency, P1N1 amplitude, or IAR of cVEMP and oVEMP (P > 0.05). There were three patients (17.65%) and two patients (11.76%) who had abnormal IAR for cVEMP and oVEMP, respectively.CONCLUSION: Routine vestibular tests may detect some findings in only a minority of patients with seasickness.Satar B, Akin Ocal FC, Karacayli C, Coban VK. Routine vestibular tests may point out vestibular subtype of seasickness only. Aerosp Med Hum Perform. 2020; 91(11):852860.

Normative Data of Ocular Vestibular Evoked Myogenic Potentials in Response to Chirp Stimulus.

OBJECTIVES: This study aims at comparing the tone-burst (TB) and narrow-band (NB) CE-chirp stimuli in terms of amplitude, latency, and interaural asymmetry ratio (IAR) in ocular vestibular evoked myogenic potentials (oVEMP). MATERIALS AND METHODS: In this prospective study, we enrolled 60 healthy subjects (27 men, 33 women) with a mean age of 25.83 (range, 18-48) years. Otological examination was normal in all the subjects. The subjects did not have any otological disease. All the subjects underwent oVEMP testing. We used 500 Hz TB stimulus and 500 Hz NB CE-chirp stimulus in random order. oVEMP test was performed at 100 dB normalized hearing level. P1 latency, N1 latency, and P1N1 amplitude were measured for each ear and stimulus, and IAR was calculated. RESULTS: Ocular VEMPs were obtained from all the subjects for both the stimuli. P1 and N1 latencies were significantly shorter in chirp stimulus than in TB stimulus for both the sides (p<0.0001). P1 and N1 amplitudes were significantly higher for chirp stimulus than for TB stimulus for both the sides (p<0.0001). There was no significant difference between the ears in IAR between the 2 types of stimuli. CONCLUSION: Narrow-band CE-chirp stimulus is an effective stimulus to evoke oVEMP with higher amplitudes and shortened latencies.

Recognizing Decompensated Meniere's Disease Using High Frequency Rotational Test.

OBJECTIVES: The purpose of this study is to investigate the effectiveness of the high-frequency rotational test for discrimination of patients with decompensated from those with compensated Meniere's disease. MATERIALS AND METHODS: Patients with unilateral Meniere's disease were divided into two groups (compensated and decompensated), based on the presence of clinically significant positional nystagmus as a determinant of the compensation status. All patients and subjects underwent pure tone audiometry, video nystagmography, and the vestibular autorotation test (VAT). The gain, phase, and asymmetry values of VAT were evaluated to range between 2 and 6 Hz. RESULTS: Phase values of horizontal vestibulo-ocular reflex (VOR) at 2.0, 2.3, and 2.7 Hz were significantly higher in the decompensated group (p<0.05). There was no significant difference in gain values, phase values, of vertical VOR and horizontal asymmetry values. CONCLUSION: Our study confirmed that horizontal phase values were determined as sensitive markers in VAT to discriminate decompensated from compensated Meniere's disease.