Impact of Prematurity on Auditory Processing in Children.

Prematurity is one of the most crucial risk factors negatively affecting the maturation of the auditory system. Children born preterm demonstrate high rates of hearing impairments. Auditory processing difficulties in preterm children might be a result of disturbances in the central auditory system development and/or sensory deprivation due to peripheral hearing loss. To investigate auditory processing in preterm children, we utilized a set of psychoacoustic tests to assess temporal processing and speech intelligibility. A total of 241 children aged 6-11 years old (136 born preterm and 105 healthy full-term children forming the control group) were assessed. The preterm children were divided into three groups based on their peripheral hearing status: 74 normal hearing (NH group); 30 children with bilateral permanent sensorineural hearing loss (SNHL group) and 32 children with bilateral auditory neuropathy spectrum disorder (ANSD group). The results showed significantly worse performance in all tests in premature children compared with full-term children. NH and SNHL groups showed significant age-related improvement in speech recognition thresholds in noise that might signify a "bottom-up" auditory processing maturation effect. Overall, all premature children had signs of auditory processing disorders of varying degrees. Analyzing and understanding the auditory processing specificity in preterm children can positively contribute to the more effective implementation of rehabilitation programs.

Safety of high-power short pulse single spot diode laser stapedotomy: an experimental animal study.

BACKGROUND: We present a new method of diode laser stapedoplasty - high-power short-pulse mode with preliminary carbonization of the waveguide and a single spot of laser ablation. AIMS/OBJECTIVE: The aim of our research is the safety evaluation of presented mode 0.98 µm diode laser cochleostomy in guinea pigs. MATERIAL AND METHODS: Guinea pigs (n = 10) received 0.98 µm diode laser cochleostomy on one ear under general anesthesia. The control group was based on untreated ears (n = 10). The assessment of auditory function was performed using the distortion product otoacoustic emission (DPOAE) before and 7 d after surgery. To assess the degree of damage from the laser cochleas were extracted for histological examination. RESULTS: To evaluate the negative impact of laser energy on OHCs and auditory function, we analyzed DPOAE amplitudes for 6400 and 8000 Hz since high frequency. The paired Student's t-test showed no statistically significant difference between the two groups. The histological examination yielded no statistically significant difference in the number of intact OHCs in the two groups. CONCLUSION AND SIGNIFICANCE: Our study confirms that the proposed method of high-power short pulse diode laser stapedotomy is safe for the inner ear. Further prospective and randomized clinical trials are required to evaluate the possible benefits of this method.

Clinical validation of the Russian Matrix test - effect of hearing loss, age, and noise level.

OBJECTIVE: To validate the Russian matrix sentence test (RUMatrix) for the assessment of speech recognition in quiet and in noise in clinical praxis. The effect of hearing impairment, age, and masking-noise level on speech recognition was examined. DESIGN: All participants underwent pure tone audiometry, a monosyllabic speech test in quiet, and speech recognition measurements with RUMatrix in quiet (SRTQ) and in noise (SRTN). STUDY SAMPLE: One hundred and forty-two listeners divided into four groups: 1. Young normal-hearing listeners, 2. Older normal-hearing listeners, 3. Young hearing-impaired listeners, and 4. Older hearing-impaired listeners. RESULTS: Significant differences between groups of listeners were found in the SRTQ and SRTN. A strong correlation between hearing threshold and SRTQ (R2=0.88, p < 0.001) indicates a strong link between speech recognition in quiet and audibility. The pure-tone average explained less variance in SRTN (R2=0.67, p < 0.001), pointing out an additional influence of suprathreshold distortion. A high test sensitivity of 0.99 was found for SRTN and SRTQ. The monosyllabic test had a low sensitivity (0.21), indicating that the test is not suitable for separating normal-hearing and hearing-impaired listeners. CONCLUSIONS: RuMatrix is a reliable speech recognition assessment tool with a high sensitivity and validity for the main aspects of hearing impairment.

Development of the Russian matrix sentence test.

OBJECTIVE: To develop the Russian matrix sentence test for speech intelligibility measurements in noise. DESIGN: Test development included recordings, optimization of speech material, and evaluation to investigate the equivalency of the test lists and training. For each of the 500 test items, the speech intelligibility function, speech reception threshold (SRT: signal-to-noise ratio, SNR, that provides 50% speech intelligibility), and slope was obtained. The speech material was homogenized by applying level corrections. In evaluation measurements, speech intelligibility was measured at two fixed SNRs to compare list-specific intelligibility functions. To investigate the training effect and establish reference data, speech intelligibility was measured adaptively. STUDY SAMPLE: Overall, 77 normal-hearing native Russian listeners. RESULTS: The optimization procedure decreased the spread in SRTs across words from 2.8 to 0.6 dB. Evaluation measurements confirmed that the 16 test lists were equivalent, with a mean SRT of -9.5 ± 0.2 dB and a slope of 13.8 ± 1.6%/dB. The reference SRT, -8.8 ± 0.8 dB for the open-set and -9.4 ± 0.8 dB for the closed-set format, increased slightly for noise levels above 75 dB SPL. CONCLUSIONS: The Russian matrix sentence test is suitable for accurate and reliable speech intelligibility measurements in noise.