Search

Objectives: The study proposes to investigate the correlation between preoperative auditory steady-state response thresholds (ASSR) and intraoperative electrically evoked compound action potential (ECAP) thresholds. Material: A total 40 patients with sensoneural hearing loss were examined using the ASSR test before cochlear implantation (CI). They were divided into 3 groups depending on the number of ASSR thresholds. Group 1: 1 threshold. Group 2: 2 thresholds. Group 3: 3 and 4 ASSR thresholds. Methods: Intraoperative ECAP registration was performed for all patients via autoART protocol (Med-El). The number of channels with recorded responses was estimated. Results: 61% of the channels of CI systems had ECAP threshold in group 1. 71% of the channels had ECAP threshold in group 2. 78% of the channels had ECAP threshold in group 3. Conclusions: ASSR test can be used to assess the condition of the cochlear nerve before CI. ASSR results can be used for choosing the ear for implantation. [ABSTRACT FROM AUTHOR]

Objectives: Today, cochlear implantation is the only treatment for the fourth degree of hearing loss and deafness. The result of cochlear implantation depends on a careful selection of patients, a high-quality operation and the right rehabilitation tactics. An extremely important stage of the operation is intraoperative monitoring, which includes telemetry of the implant state, telemetry of the nervous response and registration of the electrically induced stapedial reflex. The first two stages are performed through special modules that are integrated into the software, the third stage is performed using a surgeon who visually determines the thresholds of the stapedial reflex. The aim of our work is to determine the relationship between the thresholds of the electrically induced stapedial reflex, the thresholds of the response of the auditory nerve, recorded in automatic mode and subjective levels of the most comfortable volume. Material and methods: We examined 25 patients aged 10 months to 42 years who underwent cochlear implantation using the Concerto cochlear implant (MedEl, Austria) at St. Petersburg Research Institute of ENT SPECIALIST. The threshold of the stapedial reflex and the threshold of response of the auditory nerve at 2, 5, 8, and 11 electrodes were recorded for each patient. It is worth noting that auditory nerve response thresholds were recorded in all patients, and the stapedial reflex was recorded only in 20. We also examined 30 late-deaf patients from 18 to 54 years old with experience of wearing a speech processor from 3 to 5 years, who performed cochlear implantation using the Concerto cochlear implant (MedEl, Austria) in St. Petersburg Research Institute of ENT. Each patient was configured with two training cards. The first map was created using subjective patient ratings, and the second using automatic recording of auditory nerve responses. Stimulation was performed on all electrodes. Results and conclusions: As our study showed, the thresholds of the stapedial reflex and the thresholds of response of the auditory nerve differ very slightly. On the 2nd electrode, the difference is 2%, on the 5th electrode -- 5%, on the 8th electrode -- 10%, on the 11th electrode -- 7%. Maps created using different data were very similar in appearance to the tuning curve, however, they differed in volume. More often than not, maps created using automatic recording of auditory nerve responses were quieter than maps constructed from subjective assessments of patients. The best correlation between the maps was observed on electrodes 7 through 12. [ABSTRACT FROM AUTHOR]

Introduction: The aim of our study is to determine the characteristics of sound localization observed in patients with bilateral cochlear implantation. Methods: This study involved 38 participants with bilateral sensorineural deafness of different etiologies. Each of the participants underwent cochlear implantation of Concerto implants (Med-El, Austria). 16 of these participants underwent bilateral implantation and 22 underwent unilateral implantation. The participants' age's ranged from 7 to 21 years, with participants having previous experience of CI use from the ages of 2 to 13 years. 20 patients with intact hearing were included into the control group. In order to determine localization, an acoustic station was utilized consisting of 21 speakers arranged along a horizontal plane in a semicircular orientation. The system was connected to a sound source that generated modulated tones with a frequency of 1,000 Hz, and a sound intensity of 70 dB. Each participant received 105 modulated signals from different speakers randomly, and they had to identify the direction of the sound source. Results: During this study, it was observed that the average number of errors measured in participants with intact hearing ability was 31%, in subjects with two CIs was 84%, and in participants with one CI was 87%. It was concluded that the number of errors recorded in participants with one and with two CIs were almost the same; however, when examining the structure of the errors, a slightly different pattern was observed, whereby the average degree of error in participants with an intact hearing ability was 3,5&#176, in participants with two implants was 32.1&#176, and it was 61.2° for participants with one implant. Conclusion: The results obtained within this study show a significant improvement of the spatial sound localization in participants with two CIs when compared to those with only one CI, which demonstrates the importance of having a second ear cochlear implantation performed. [ABSTRACT FROM AUTHOR]

Objectives. It has been suggested that the density of spiral ganglion neurons will affect on speech intelligibility. The results of previous studies shows that the supra-threshold characteristics of the Evoked Compound Action Potentials (ECAP) characterize the condition of spiral ganglion neurons. Aim of this paper is to evaluate the dependence of maximum comfort levels on ECAP parameters (threshold and amplitude). Materials and methods. The study included fitting data of 20 patients with sensorineural hearing loss with unilateral cochlear implantation. All patients were implanted with the Med-El (Sonata or Concerto) CI system with a standard electrode array. The results of electrodes impedance did not exceed 10 kΩ. Auditory development was assessed depending on the age of the patient and the condition of the hearing skills. Recognition results exceeded 90%. Results. A correlation between comfort levels and ECAP thresholds was found. The values of the comfort levels were reduced when ECAP amplitude was increased. Conclusions. ECAP thresholds can not be considered as an absolute reference point for determining the CI comfort levels. The amplitude of the ECAP response is one of the indicators of the preservation of the neurons of the auditory nerve. The correlation of the ECAP thresholds and comfort levels higher when ECAP amplitude values increase. [ABSTRACT FROM AUTHOR]

The article is devoted to the problems of binaural cochlear implantation, especially in patients with a long time interval between surgeries. The purpose of the study was to evaluate the effect of the time range between successive interventions in patients with binaural prosthetics using the CI system., Materials and Methods: the study included 50 patients aged 10 to 14 years, divided into 3 study groups: patients with unilateral cochlear implantation (group I), patients with bilateral implantation with a less than 1 year range between operations (group II) and patients with bilateral implantation with a more than 5 year range between interventions (group III). Comparative analysis was carried out using speech audiometry in silence and noise, assessment of sound localization and questionnaires to assess the auditory dynamics and speech development., Results: Patients in groups II and III showed comparable results in speech intelligibility in noise and sound localization. At the same time, these indicators turned out to be higher than in patients of group I. Patients from all three groups did not show statistically significant differences in speech intelligibility in silence and in the level of speech development., Conclusion: a long interval (more than 5 years) after the first implantation should not be considered as a contraindication to binaural implantation.

Objective: To evaluate the hearing outcomes of cochlear implantation in different age groups by using data collected in the HEARRING registry., Methods: A multicenter study. Data of 146 patients were collected in a HEARRING registry. Patients were divided into three different age groups; ≤ 55 years old (age group 1, n = 66), 56 to 69 years old (age group 2, n = 45), and ≥ 70 years old (age group 3, n = 35). Speech in quiet (SPIQ), speech in noise (SPIN), and hearing implant sound quality index (HISQUI19) scores were evaluated for the different age groups at different test moments (preoperatively, 3, 6, 12, and 24 mo after first fitting)., Results: A statistically significant difference (p < 0.01) was found between preoperative scores and the scores on all the follow-up moments across all age groups. For SPIQ and SPIN, none of the time points showed a statistically significant age effect (p = 0.88 and p = 0.89). For HISQUI19 scores, a statistically significant age effect was found at 12 months after first fitting. The oldest age group scored significantly lower on the HISQUI19 compared with the youngest age group., Conclusion: Hearing outcomes of adult cochlear implant users of different age groups were evaluated. The SPIQ and SPIN tests showed no significant differences between the different age groups. Nevertheless, the youngest group scored significantly better on self -perceived benefit (HISQUI19) with a cochlear implant compared with the oldest age group.Further research is needed to receive more insight into cochlear implantation in the elderly and its implications on rehabilitating and supporting this expanding older population.

Objective: To determine the time needed to remotely perform a set of intraoperative measurements during cochlear implantation surgery and to compare it to the time needed to perform the same measurements in theatre., Design: Prospective two-arm study comparing a local with a remote measurement setting. Three intraoperative measurements (Impedance Field Telemetry (IFT), evoked compound action potential (ECAP) and evoked stapedius reflex test (eSRT)) were performed with the audiologist present in the operating theatre (i.e. locally) or with the audiologist in his/her office (i.e. remotely). The time needed to complete the measurements, in total and individually, were measured and compared., Study Sample: Fifty cochlear implant recipients, aged 0.7-48 years Results: IFT, ECAP and eSRT were performed successfully in all participants. Comparing locally and remotely performed measurements, IFT did not differ significantly, ECAP threshold or slope did not differ significantly differ in any single channel and eSRT measurements did not differ significantly except for in one of six channels. Remote measurements took 8.6 min less to perform than did local measurements (10.04 vs. 18.64 min); a significant difference (p < 0.001)., Conclusions: Using a remote network connection for intraoperative objective measurements is an efficient and safe way to perform measurements during cochlear implantation surgery.