Stapedial Reflex: A Possible Novel Biomarker of Early Bulbar Involvement in Amyotrophic Lateral Sclerosis Patients.

BACKGROUND AND AIM: Amyotrophic lateral sclerosis (ALS) is a neuromuscular progressive disorder, characterized by limb and bulbar muscle wasting and weakness. 30% of patients present a bulbar onset, while 70% a spinal outbreak, although most of them develop bulbar impairment later on. Due to the lack of an early biomarker of bulbar involvement, we chose to evaluate the role of stapedial reflex (SR) in order to predict preclinical bulbar impairment in ALS. MATERIALS AND METHODS: We enrolled 36 ALS patients. We assessed revised-ALS functional-rating-scale and SR for a total of 4 visits. We established the presence of SR, acoustic reflex latency test (ARLT), and SRs Decay. Patients who had not develop bulbar signs at fourth visit continued follow-up up to 15 months. Data were analyzed by using Mann-Whitney U test, Friedman test, and Cox regression analysis. RESULTS: We observed that SRs Decay at 500 and 1,000 Hz is the first parameter of SR to get altered in all ALS patients before the development of bulbar impairment. Twenty-eight patients developed bulbar impairment during the study. We highlighted a correlation between the progression rate of disease and both time of SRs Decay alteration and time of bulbar impairment from disease onset. Four patients who did not develop bulbar impairment had a progression rate lower than the other ones (p < 0.05). DISCUSSION AND CONCLUSIONS: This study shows that SR Decay test could be a sensitive measure for detecting pre-symptomatic bulbar involvement in ALS and could represent a simple, noninvasive, and useful biomarker of disease progression.

A new bone conduction hearing aid to predict hearing outcome with an active implanted device.

PURPOSE: We compared our historical medium-term data obtained with an active semi-implanted bone conduction device and the hearing results of a new passive bone conduction hearing device to determine its predictive value for the hearing results with the semi-implanted device. METHODS: The study sample was 15 patients with an active bone conduction implant (mean follow-up 26 months). Pure tone audiometry was performed with headphones, sound field speech audiometry was conducted unaided, and free-field speech audiometry was carried out with both the active bone conduction system and the passive device switched off. RESULTS: As compared with the unaided condition, speech reception was significantly improved with both devices. Comparison of speech reception threshold at 100% of word recognition showed no difference between the active and the passive device. At lower intensity the difference in speech perception was significant in the patients with monaural fitting (group A) and was non-statistically significant in those with binaural fitting (group B); the speech reception threshold at 50% of word recognition was 26.00 dB (± 10.22) with the active implant and 30.50 dB (± 7.98) with the passive device in group A (p = 0.047) and 24.00 dB (± 5.48) and 29.00 dB (± 2.24) in group B (p = 0.052), respectively. CONCLUSIONS: The hearing outcome after active bone conduction implant was comparable to published data. Compared with the unaided condition, speech recognition was significantly improved with the passive device. The device may also provide value to predict the hearing outcome with the implanted device, especially at higher intensities. LEVEL OF EVIDENCE: IV.

Comparison of VEMPs, VHIT and caloric test outcomes after vestibular neurectomy in Menière's disease.

OBJECTIVE: Selective unilateral vestibular neurectomy (VN) is considered a reliable surgical treatment in case of recurrent vertigo in Menière's disease (MD) because of hearing preservation and a minimally invasive posterior fossa retrosigmoid approach. The present study aimed to assess the quality of life and the long-term vestibular function in patients submitted to yearly follow-up after VN because of intractable MD. METHODS: Retrospective series of 15 MD patients undergoing retrosigmoid VN for recurrent vertigo. Outcome measures included cVEMPs and oVEMPs (cervical and ocular vestibular evoked myogenic potentials), VHIT (Video Head Impulse Test) and caloric test, besides to DHI (Dizziness Handicap Inventory) and PTA (Pure Tone Audiometry). RESULTS: Mean DHI score resulted within normal values in 74% of patients, significantly correlated to the duration of the follow-up. In the operated side, cVEMPs and oVEMPs have not been elicited respectively in 11 patients (73%) and 13 patients (87%), whereas it was not possible to evoke any response at bithermal caloric test in 4 cases. The gain of VOR from VHIT resulted always below normal values after VN except in one patient, who has also undergone an episode of posterior BBPV. The difference between average PTA threshold before and after VN resulted not significant. CONCLUSION: The vestibular outcomes prove VN to be an effective and safe surgery in MD; furthermore, the unexpected occurrence of BPPV after VN can justify the presence of neural anastomosis between the inferior vestibular nerve and the cochlear nerve, allowing to still perceive vestibular symptomatology despite of a proper neurectomy.

Acoustic reflex patterns in amyotrophic lateral sclerosis.

The aim of the study is to investigate acoustic reflex testing in amyotrophic lateral sclerosis patients. Amplitude, latency, and rise time of stapedial reflex were recorded for 500 and 1000 Hz contralateral stimulus. Statistical analysis was performed by the Wilcoxon test and the level of significance was set at 5 %. Fifty-one amyotrophic lateral sclerosis patients and ten sex- and age-matched control subjects were studied. Patients were further divided in two groups: amyotrophic lateral sclerosis-bulbar (38 cases, with bulbar signs at evaluation) and amyotrophic lateral sclerosis-spinal (13 cases, without bulbar signs at evaluation). Stapedial reflex was present in all patients. There was a statistically significant difference in the mean amplitude, latency, and rise time between the amyotrophic lateral sclerosis patients as compared with the controls. Amplitude was lower in both the amyotrophic lateral sclerosis-bulbar and the amyotrophic lateral sclerosis-spinal patients than in the controls (p < 0.05) and rise time was longer in both patient groups compared with the controls (p < 0.05). These results confirm the presence of abnormal acoustic reflex patterns in amyotrophic lateral sclerosis cases with bulbar signs and, moreover, suggesting a possible subclinical involvement of the stapedial motor neuron even in amyotrophic lateral sclerosis-spinal patients. Amplitude and rise time seem to be good sensitive parameters for investigating subclinical bulbar involvement.

Prevention and management of hearing loss in syndromic craniosynostosis: A case series.

OBJECTIVE: To assess the audiological profile in a cohort of children affected by syndromic craniosynostosis. METHODS: Eleven children with Apert syndrome (n=4), Saethre-Chotzen syndrome (n=3), Muenke syndrome (n=2), Crouzon syndrome (n=1) and Pfeiffer syndrome type 1 (n=1) were submitted to a complete audiologic evaluation including otoscopy, pure-tone audiometry, tympanometry and acoustic reflex testing, ABR, otoacustic emissions, temporal bone High Resolution CT (HRCT) scan. The main outcome measures were prevalence, type and severity of hearing loss, prevalence of chronic otitis media, correlation with the time of first surgical correction. RESULTS: Seven of 11 patients (64%) presented hearing loss (HL), conductive in 3/7 patients (43%) and mixed in 4/7 (57%). No patients showed a purely sensorineural HL. All hearing impaired patients displayed middle ear disorders: the patients with conductive HL had otitis media with effusion (OME) and 3/4 patients with mixed HL showed tympanic alterations or cholesteatoma. A bilateral vestibular aqueduct enlargement was detected by HRCT scan in one normal hearing patient. The ABRs resulted normal in all cases. CONCLUSION: Our study confirms the high prevalence of otologic diseases in such patients. In contrast with previous studies, middle ear disorders were responsible for the hearing impairment also in patients with mixed HL due to secondary inner ear damage. These findings restate the necessity of a close audiologic follow-up. We did not detect the specific ABR abnormalities previously reported, possibly because of an early correction of the cranial vault malformations.

Monaural or binaural sound deprivation in postlingual hearing loss: Cochlear implant in the worse ear.

OBJECTIVES/HYPOTHESIS: To determine whether speech recognition scores (SRS) differ between adults with long-term auditory deprivation in the implanted ear and adults who received cochlear implant (CI) in the nonsound-deprived ear, either for hearing aid-assisted or due to rapidly deteriorating hearing loss. STUDY DESIGN: Retrospective study. METHODS: Speech recognition scores at evaluations (3 and 14 months postimplantation) conducted with CI alone at 60-dB sound pressure level intensity were compared in 15 patients (4 with bilateral severe hearing loss; 11 with asymmetric hearing loss, 7 of which had contralateral hearing aid), all with long-term auditory deprivation (mean duration 16.9 years) (group A), and in 15 other patients with postlingual hearing loss (10 symmetric, 5 asymmetric with bimodal stimulation) (controls, group B). RESULTS: Comparison of mean percentage of correctly recognized words on speech audiometry at 3 and 14 months showed improvement within each group (P < 0.05). Between-group comparison showed no significant difference at 3 (P = 0.17) or 14 months (P = 0.46). Comparison of SRSs in group A (bimodal stimulation [n = 7] and binaural sound deprivation [n = 4]) versus group B showed no significant differences at 3 (bimodal stimulation P = 0.16; binaural sound deprivation P = 0.19) or 14 months (bimodal stimulation P = 0.14; binaural sound deprivation P = 0.82). CONCLUSIONS: Speech recognition scores in monaural and binaural sound-deprived ears did not significantly differ from ears with unilateral cochlear implantation in nonsound-deprived ears when tested with CI alone. Improvement in the implanted worse ear indicates that it could be a potential candidate ear for cochlear implantation even when sound deprived. LEVEL OF EVIDENCE: 4. Laryngoscope, 126:1905-1910, 2016.

Cochlear Nerve Stimulation in the Internal Auditory Canal in Ossified Cochlea: A Case Study.

OBJECTIVE: To present the first reported case of intraneural direct cochlear nerve stimulation in a human being. STUDY DESIGN: This is a case report. RESULTS: A 23-year-old patient with bilateral progressive hearing loss associated with bilateral complete semicircular canal aplasia and ossified cochleas underwent cochlear implantation. During surgery, a patent cochlear lumen could not be found, and the array was positioned in the internal auditory canal adjacent to the cochlear nerve. Against our expectations, an assiduous rehabilitation and frequent fitting adjustments have led to a word recognition score, in open set speech with lip reading, of 18/25 and acceptable frequency discrimination. CONCLUSIONS: We are aware that this was an anomalous use of the cochlear implant, and it is not our aim to suggest a new indication for cochlear array positioning. However, this case shows that auditory perception, to some degree, can be obtained with intraneural direct cochlear nerve stimulation.

The role of the efferent auditory system in developmental dyslexia.

OBJECTIVE: To assess the role of the efferent auditory system by inhibition of contralateral otoacoustic emission in dyslexic children with auditory processing disorders. METHODS: The study sample was 34 children: 17 with dyslexia and 17 age-matched controls. Sensitive speech tests (low-pass filtered, time-compressed, distorted and dichotic) were performed to assess coexisting auditory processing disorder. Distortion-product otoacoustic emission (DPOAE) values were measured in basal condition and with contralateral broadband noise signal delivered via an earphone transducer at 60 dB SPL. RESULTS: The lower scores at sensitive speech testing confirmed the association of an auditory processing disorder in the dyslexic children. DPOAE values were significantly attenuated by contralateral inhibition only in the control group (p=0.001; dyslexics, p=0.19); attenuation was not significant at any frequency in the dyslexic group. CONCLUSIONS: The differences in DPOAE attenuation between the groups, although not statistically significant, suggest alterations in the auditory efferent system in the dyslexic population. These alterations may affect language perception. If confirmed in further studies with larger samples, these results could provide insight into a possible pathophysiological background of dyslexia.

Oval and round window vibroplasty: a comparison of hearing results, risks and failures.

The aim of this study was to compare oval and round window vibroplasty. Eighteen (18) patients implanted with Vibrant Soundbridge (VSB) were enrolled. Two groups were formed depending on FMT placement: on round window in ten cases (RW group) and on oval window in eight (OW group). Pre and postoperative audiological tests were performed both under headphones and free-field settings, VSB on and off. One (1) RW patient experienced sudden hearing loss at the operated side after 4 months from surgery and was excluded from the analysis. Both groups showed good hearing results. Significant differences were measured at free-field pure-tone test with VSB on at 0.5 kHz (RW better than OW, p = 0.026) and 4 kHz (OW better than RW, p = 0.043). Both techniques share similar good results and are considered safe. However, we had one failure with deep and sudden hearing threshold worsening after some months of good results. From a surgical point of view OW vibroplasty is easier and safer to perform, when the stapes suprastructure is absent, as it does not require any drilling and should be preferred in such cases. More reports are needed to explain if RW vibroplasty is risky in a mid to long term.

Tone burst stimulus for auditory brainstem responses: prediction of hearing threshold at 1kHz.

OBJECTIVE: To assess differences in hearing threshold estimation of four different ABR tone-bursts at 1kHz. METHODS: Twenty-one (21) ears from 11 subjects were tested with pure-tone audiometry (PTA): 5 ears (24%) were normal hearing, 5 (24%) affected by mild hearing loss, 7 (33%) showed moderate hearing loss and 4 (19%) severe hearing loss. After PTA each subject underwent tone-burst ABR test at 1kHz using a linear gated (L_ABR) or Blackman windowed (B_ABR) stimuli with (nn_ABR) and without ipsilateral notched noise. Stimulation rate and filters settings were unchanged. RESULTS: Overall correlation between PTA and all ABRs thresholds was high, ranging from 0.84 to 0.94. In normal hearing ears none of the differences was significant, except for those measured with B_nn_ABR, which showed a mean 16dB overestimation of the pure-tone threshold (p<0.05). In mild hearing loss group none of the differences between thresholds were significant. In moderate and severe hearing loss groups significant differences were measured with L_nn_ABR (p<0.05) with a mean 7.5dB underestimation of PTA. CONCLUSIONS: Although very similar, some significant differences were found when considering specific group of patients with different degrees of hearing loss.

Relationship between pure tone audiometry and tone burst auditory brainstem response at low frequencies gated with Blackman window.

To assess the reliability of Blackman windowed tone burst auditory brainstem response (ABR) as a predictor of hearing threshold at low frequencies. Fifty-six subjects were divided in to three groups (normal hearing, conductive hearing loss, sensorineural hearing loss) after pure tone audiometry (PTA) testing. Then they underwent tone burst ABR using Blackman windowed stimuli at 0.5 kHz and 1 kHz. Results were compared with PTA threshold. Mean threshold differences between PTA and ABR ranged between 11 dB at 0.5 kHz and 14 dB at 1 kHz. ABR threshold was worse than PTA in each but 2 cases. Mean discrepancy between the two thresholds was about 20 dB in normal hearing, reducing in presence of hearing loss, without any differences in conductive and sensorineural cases. Tone burst ABR is a good predictor of hearing threshold at low frequencies, in case of suspected hearing loss. Further studies are recommended to evaluate an ipsilateral masking such as notched noise to ensure greater frequency specificity.

Noise-induced hearing loss evolution: influence of age and exposure to noise.

The aims of this study were to evaluate the influence of age and exposure to noise in determining the evolution of hearing loss after noise-induced hearing loss has been already established and to define the further evolution of presbycusis. This is a cross-sectional study based on the evaluation of pure-tone audiometry threshold on 568 subjects affected by noise-induced hearing loss and exposed to noise for at least 10 years; noise exposure at testing was 85-90 dB Leqd(A). The further evolution of hearing loss was found to be more related to age than to noise exposure and was significantly less than expected for presbycusis. In conclusion our data support the hypothesis that once NIHL has manifested, it tends to worsen slightly with continued noise exposure and that progressive hearing loss is chiefly due to aging. However, in individuals with NIHL, age-related hearing loss is significantly less at frequencies damaged by noise than in non-noise-exposed individuals.

Monitored anesthesia care with target-controlled infusion in vibroplasty.

OBJECTIVES: Correct positioning of a floating mass transducer during middle ear implant surgery is often problematic. With the use of monitored anesthesia care (MAC), however, deep sedation is maintained during surgery, followed by conscious sedation in which the patient can respond to test questions that investigate correct device position and function. The main aim of this study was to determine whether intraoperative audiometric assessment was feasible with MAC with target-controlled infusion in vibroplasty. An additional aim was to determine whether MAC was sufficiently comfortable for patients during the procedure. METHODS: The study group comprised 8 patients who underwent vibroplasty under sedation. Before suturing, audiometric assessment was done by stimulating the external auditory processor with pure tones at 0.5, 1,2, and 4 kHz. Blood pressure, arterial oxygen saturation level, heart rate, and end tidal carbon dioxide level were monitored during the procedure and at awakening. RESULTS: Audiometric assessment was successfully completed in all 8 patients. The selected parameters indicated that no patient experienced pain or discomfort during surgery; the absence of discomfort was confirmed 1 to 2 hours after the operation by simple questioning. CONCLUSIONS: We found MAC to be an efficient and relatively safe technique for verifying the correct coupling of the floating mass transducer with the middle ear during vibroplasty. The patients were able to respond appropriately to questions and commands; moreover, none reported having experienced pain or discomfort during the operation.

Equine versus bovine pericardium in transmeatal underlay myringoplasty.

OBJECTIVES: Many different grafting materials have been proposed in myringoplasty. The aim of this study was to evaluate the results obtained in transmeatal underlay myringoplasty using bovine and equine pericardium. The results were compared with those obtained by using autologous temporalis fascia. METHODS: The study group consisted of 52 patients with tympanic perforation. Twenty-nine patients were randomly selected for treatment with bovine pericardium and 23 for equine pericardium. A group of 14 patients was treated with autologous temporalis fascia. RESULTS: Closure of the perforation was achieved in 19 of 29 patients (66%) treated with bovine pericardium, in 19 of 23 (83%) treated with equine pericardium, and in 13 of 14 (93%) treated with autologous fascia. The best functional results in patients who gained closure of the perforation were obtained by means of equine pericardium. CONCLUSIONS: The overall long-term tympanic closure rate demonstrates that equine pericardium has a greater take rate than bovine pericardium. The results obtained are inferior to those obtained with autologous fascia, but this technique is less aggressive. The higher success rate with equine pericardium may be due to the fact that it is thinner and easier to handle and model than bovine pericardium.

Condition of the anterior part of the middle ear cleft in acquired cholesteatoma.

CONCLUSION: The high rate of flogistic suffering of the controlateral ear seems to suggest a correlation between tubal dysfunction and acquired cholesteatoma but the low rate of pathological reports regarding the anterior mesotympanic region exclude a eustachian tube dysfunction (EDT) at the time of surgery. These observations support the hypothesis that ETD is not a factor that may influence the evolution of the cholesteatoma. OBJECTIVES: To evaluate the role of eustachian tube function in the middle ear secondary acquired cholesteatoma. PATIENTS AND METHODS: This was a case series study. The study group consisted of 72 patients submitted to tympanoplasty for middle ear secondary acquired cholesteatoma. RESULTS: The contralateral ear was normal in 37 subjects (51%) and affected by chronic otitis media in 35 (49%); the anterior part of middle ear cleft was normal in 53 patients (74%). There was no significant relationship between the contralateral ear condition and the status of the anterior region of middle ear (p>0.05). The site of retraction or the presence of tympanic perforation with skin migration was not related to the condition of the protympanum. Otorrhea, cholesteatoma extension, and ossicular chain lesions were not significantly related to the status of the anterior part of the middle ear cleft (p>0.05).

Auditory steady-state responses and clinical applications.

The auditory steady-state responses to single continuous tones modulated in amplitude have been proposed as an alternative to objective frequency-specific audiometry. The aim of this study was to compare thresholds obtained by pure-tone audiometry (PTA) and by auditory steady-state responses in normal hearing or affected by hearing loss in adults and in order to evaluate the applicability of this objective test in no collaborative hearing-impaired subjects. Eleven people, 6 normal hearing and 5 with hearing loss, underwent PTA and multiple frequency auditory steady-state responses; simultaneous carrier tones (0.5, 1, 2 and 4 KHz) modulated in amplitude at different rates (77-105 Hz) were presented monaurally (TDH 49 earphones) at variable intensities (110-20 dB SPL). The mean threshold difference between PTA and multiple frequency auditory steady-state responses was 28 dB (standard deviation=14.2) and R correlation value at 0.5-1-2-4 kHz was 0.71 (P=0.0012) at the Pearson's test. These differences were significantly smaller considering the hearing-impaired separately (11.7 dB, standard deviation=2.9). The results of this study confirm previous reports showing that the multiple auditory steady-state response method is an accurate predictor of the behavioural audiogram in patients with sensory-neural hearing impairments and can be used as a valid support for behavioural evaluations.

Tympanic reperforation in myringoplasty: evaluation of prognostic factors.

OBJECTIVES: The most frequent failure in myringoplasty is reperforation. This complication appears at a rate of 7% to 27%. The aim of this study was to evaluate the importance of the principal prognostic factors to the risk of reperforation. METHODS: This is a study of prognosis based on an inception cohort. The prognostic factors considered in the study refer to clinical and surgical aspects; follow-up ranged from 5 to 7 years (mean, 68 months). The study was performed on 212 patients with or without otorrhea who underwent operation for tympanic perforation. All subjects underwent myringoplasty by means of an underlay or overlay technique depending on the size and site of the perforation. RESULTS: Healing of the tympanic perforation was obtained in 182 cases (86%). Age, otorrhea, status of the contralateral ear, and conductive hearing loss did not significantly affect the outcome of surgery. On the other hand, time from surgery, the site of perforation, the type of anesthesia, the approach, the surgical technique, and the type of graft were significantly related to the outcome. CONCLUSIONS: In the analysis of our results, the surgical approach proved to be the principal prognostic factor in the anatomic outcome of myringoplasty. The results obtained suggest that the principal factors influencing the outcome of myringoplasty are technical and not clinical.

The prognostic value of the otoacoustic emission test in low frequency sudden hearing loss.

Low frequency sudden hearing loss (LFSHL) is a frequent finding in the otological practice. Several prognostic indicators have been suggested concerning the prediction of the outcome of sudden hearing loss, but so far there are no proven factors to establish the prognosis. The aim of this study was to assess whether OAEs could be considered as a reliable prognostic test in LFSHL. The study group consisted of 20 patients presenting with a unilateral LFSHL. Each patient was submitted to spontaneous otoacoustic emissions (SOAEs), transient otoacoustic emissions (TEOAEs) and distortion products (DPOAEs) recording and then treated with glycerol administrated intravenously in 3-h intervals for 4 days. Pure tone audiometry (PTA) threshold was evaluated again 1 h after the last administration of glycerol. After osmotic therapy 12 patients (60%) showed a significant PTA improvement with a mean improvement of 11 dB; modifications were significant at the Student's t test for paired data (P<0.0001). The relationship between the pretherapy presence or absence of SOAEs, TEOAEs and DPOAEs and PTA modification was not significant at the exact Fisher's test. In conclusion, even if our study supports that OAEs could be an indicator of the inner ear functional state, they cannot be utilized as a prognostic test in LFSHL in relation to the efficacy of osmotic therapy. Among the other parameters evaluated, only the precocity of therapy seems to be related to prognosis in LFSHL.

Delayed vertigo after stapes surgery.

OBJECTIVES: Stapes surgery restores partial or total hearing in almost 95% of cases, and in case of failure, revision surgery may often resolve the problem. Delayed vertigo is commonly related to perilymphatic fistula. The aim of this study is to report experience gained in revision stapes surgery in cases of delayed vertigo. STUDY DESIGN: This is an intervention study, before-after trial; it includes follow-up between 12 and 84 months that was based on clinical history and audiometric evaluations. METHODS: The work was carried out in the otologic surgery referral center of Piemonte in outpatient surgery. Nine patients (4 males and 5 females, between 43 and 60 years of age) who presented with delayed vertigo after stapes surgery were retrospectively reviewed. All nine underwent clinical history evaluation, pure tone audiogram, investigation of the vestibular system with a bithermal binaural caloric test, and fistula test. Vestibular tests were performed with electronystagmography recording. In all nine subjects, functional middle ear exploration was carried out by way of a transmeatal approach using local anesthesia. The demonstration of a perilymphatic leak was positive in only three (33%) cases, but the oval window region was filled with fibrin glue in all nine cases. RESULTS: At follow-up, vertigo was resolved in all cases with revision surgery, even though perilymph leak was positive only in three cases. CONCLUSION: From the results obtained, we feel that exploration of the middle ear should be always carried out in cases of delayed vertigo after stapes surgery with suspected perilymphatic fistula.