We have investigated the effectiveness of three noise-reduction algorithms, namely an adaptive monaural beamformer (MB), a fixed binaural beamformer (BB), and a single-microphone stationary-noise... Show moreWe have investigated the effectiveness of three noise-reduction algorithms, namely an adaptive monaural beamformer (MB), a fixed binaural beamformer (BB), and a single-microphone stationary-noise reduction algorithm (SNRA) by assessing the speech reception threshold (SRT) in a group of 15 bimodal cochlear implant users. Speech was presented frontally towards the listener and background noise was established as a homogeneous field of long-term speech-spectrum-shaped (LTSS) noise or 8-talker babble. We pursued four research questions, namely: whether the benefits of beamforming on the SRT differ between LTSS noise and 8-talker babble; whether BB is more effective than MB; whether SNRA improves the SRT in LTSS noise; and whether the SRT benefits of MB and BB are comparable to their improvement of the signal-to-noise ratio (SNR). The results showed that MB and BB significantly improved SRTs by an average of 2.6 dB and 2.9 dB, respectively. These benefits did not statistically differ between noise types or between the two beamformers. By contrast, physical SNR improvements obtained with a manikin revealed substantially greater benefits of BB (6.6 dB) than MB (3.3 dB). SNRA did not significantly affect SRTs per se in omnidirectional microphone settings, nor in combination with MB and BB. We conclude that in the group of bimodal listeners tested, BB had no additional benefits on speech recognition over MB in homogeneous noise, despite the finding that BB had a substantial larger benefit on the SNR than MB. SNRA did not improve speech recognition. Show less
Previously, mutations in the AMMECR1 gene have been described in six males with developmental delay, sensorineural hearing loss (SNHL) and/or congenital abnormalities, including fetal nuchal edema,... Show morePreviously, mutations in the AMMECR1 gene have been described in six males with developmental delay, sensorineural hearing loss (SNHL) and/or congenital abnormalities, including fetal nuchal edema, fetal pericardial effusion, talipes, congenital hip dysplasia, elliptocytosis and cleft palate. In this report, we present three female relatives of a male fetus with an intragenic deletion in this X-linked gene. All three women reported hearing loss and one was born with a soft cleft palate and hip dysplasia. The audiograms showed mild to moderate SNHL with a variable pattern of the affected frequencies. Immunohistochemical analysis of fetal cochlea was performed confirming the expression of AMMECR1 in the human inner ear. Since hearing loss, cleft palate and congenital hip dysplasia were reported before in male AMMECR1 point mutation carriers and AMMECR1 is expressed in fetal inner ear, we suggest that female carriers may display a partial phenotype in this X-linked condition. Show less
Objectives: Video head impulse test (v-HIT) is a quick, non-invasive and relatively cheap test to evaluate vestibular function compared to the caloric test. The latter is, however, needed to decide... Show moreObjectives: Video head impulse test (v-HIT) is a quick, non-invasive and relatively cheap test to evaluate vestibular function compared to the caloric test. The latter is, however, needed to decide on the optimal side to perform cochlear implantation to avoid the risk on inducing a bilateral vestibular areflexia. This study evaluates the effectiveness of using the v-HIT to select cochlear implant (CI) candidates who require subsequent caloric testing before implantation, in that way reducing costs and patient burden at the same time. Study Design: Retrospective study using clinical data from 83 adult CI-candidates, between 2015 and 2020 at the Leiden University Medical Center. Materials and Methods: We used the v-HIT mean gain, MinGain_LR, the gain asymmetry (GA) and a newly defined parameter, MGS (Minimal Gain & Saccades) as different models to detect the group of patients that would need the caloric test to decide on the ear of implantation. The continuous model MGS was defined as the MinGain_LR, except for the cases with normal gain (both sides >= 0.8) where no corrective saccades were present. In the latter case MGS was defined to be 1.0 (the ideal gain value). Results: The receiver operating characteristics curve showed a very good diagnostic accuracy with and area under the curve (AUC) of 0.81 for the model MGS. The v-HIT mean gain, the minimal gain and GA had a lower diagnostic capacity with an AUC of 0.70, 0.72, and 0.73, respectively. Using MGS, caloric testing could be avoided in 38 cases (a reduction of 46%), with a test sensitivity of 0.9 (i.e., missing 3 of 28 cases). Conclusions: The newly developed model MGS balances the sensitivity and specificity of the v-HIT better than the more commonly evaluated parameters such as mean gain, MinGain_LR and GA. Therefore, taking the presence of corrective saccades into account in the evaluation of the v-HIT gain can considerably reduce the proportion of CI-candidates requiring additional caloric testing. Show less
Cochlear implant (CI) users have more difficulty understanding speech in temporally modulated noise than in steady-state (SS) noise. This is thought to be caused by the limited low-frequency... Show moreCochlear implant (CI) users have more difficulty understanding speech in temporally modulated noise than in steady-state (SS) noise. This is thought to be caused by the limited low-frequency information that CIs provide, as well as by the envelope coding in CIs that discards the temporal fine structure (TFS). Contralateral amplification with a hearing aid, referred to as bimodal hearing, can potentially provide CI users with TFS cues to complement the envelope cues provided by the CI signal. In this study, we investigated whether the use of a CI alone provides access to only envelope cues and whether acoustic amplification can provide additional access to TFS cues. To this end, we evaluated speech recognition in bimodal listeners, using SS noise and two amplitude-modulated noise types, namely babble noise and amplitude-modulated steady-state (AMSS) noise. We hypothesized that speech recognition in noise depends on the envelope of the noise, but not on its TFS when listening with a CI. Secondly, we hypothesized that the amount of benefit gained by the addition of a contralateral hearing aid depends on both the envelope and TFS of the noise. The two amplitude-modulated noise types decreased speech recognition more effectively than SS noise. Against expectations, however, we found that babble noise decreased speech recognition more effectively than AMSS noise in the CI-only condition. Therefore, we rejected our hypothesis that TFS is not available to CI users. In line with expectations, we found that the bimodal benefit was highest in babble noise. However, there was no significant difference between the bimodal benefit obtained in SS and AMSS noise. Our results suggest that a CI alone can provide TFS cues and that bimodal benefits in noise depend on TFS, but not on the envelope of the noise. Show less
Kleijwegt, M.; Bettink, F.; Malessy, M.; Putter, H.; Mey, A. van der 2020
Objective This study was aimed to determine the role of clinical presentation and tumor characteristics in vestibular schwannoma (VS) at diagnosis, initially treated with conservative management... Show moreObjective This study was aimed to determine the role of clinical presentation and tumor characteristics in vestibular schwannoma (VS) at diagnosis, initially treated with conservative management.Design The study was designed as a retrospective chart review.Setting The study was prepared at national tertiary referral center for VS patients.Participants A total of 836 VS patients, initially treated conservatively, were included.Main Outcome Measures Patient characteristics: age at diagnosis, gender, frequency, and duration of, hearing loss, tinnitus, balance disorder (unsteadiness, dizziness, and vertigo), respectively; and tumor characteristics: laterality, growth, cystic component, and location were analyzed in relation to tumor size at diagnosis and change in treatment strategy.Results In total, 169 (20%) patients had a change in treatment strategy. Factors at diagnosis that had a high influence on intervention were a short duration of hearing loss (hazard ratio [HR]: 4.8, p <0.001) and cystic tumors (HR=2.6, p <0.001). Balance disorders and extracanalicular (EC) tumor location have a medium influence on intervention (HR=1.6, p <0.01). Tumour growth was seen in 55% of the intervention group; we found a significant correlation with a short duration of hearing loss. Cystic VS was significantly higher between the medium and large tumors, 24.3% and 38.1%. ( p =0.001), respectively.Conclusions Patients with a short duration of hearing loss, balance disorders, EC located tumors, and cystic tumors have a significantly higher chance of a change in treatment strategy. Large tumor size at diagnosis and a cystic component were related to age>65 years at diagnosis. Show less
BackgroundBoth radiotherapy (RT) and cisplatin-based chemoradiotherapy (CRT) in patients with head and neck cancer may cause sensorineural hearing loss (SNHL). The purpose of this review was to... Show moreBackgroundBoth radiotherapy (RT) and cisplatin-based chemoradiotherapy (CRT) in patients with head and neck cancer may cause sensorineural hearing loss (SNHL). The purpose of this review was to provide more insight into SNHL because of CRT compared to RT.MethodsComprehensive search of Medline and Embase with the terms radiotherapy combined with ototoxicity, head and neck squamous cell carcinoma, and synonyms.ResultsOf the 2507 studies found, 21 were included in this study. Pooled analysis could not be committed because of heterogeneity. Incidence rates of SNHL after RT and CRT varied considerably, with percentages ranging from 0% to 43% and 17% to 88%, respectively. Factors that influenced the risk of SNHL were radiation dose to the cochlea, follow-up time, age, baseline hearing level, and cisplatin dose.ConclusionThe wide range of SNHL incidence rates makes it impossible to draw any conclusions on the severity of RT- and CRT-induced ototoxicity. To allow for future comparison of study outcomes, development of uniform criteria is of utmost importance. (c) 2014 Wiley Periodicals, Inc. Head Neck37: 281-292, 2015 Show less
