Biomedical subjects

Ricky Kaplan-Neeman

Publications and source records attributed to Ricky Kaplan-Neeman.

8 recordsLinked to original sources

PubMed2006

A longitudinal study of electrical stimulation levels and electrode impedance in children using the Clarion cochlear implant.

CONCLUSIONS: Electrical stimulation levels and electrode impedance values (EIVs) in children using the Clarion cochlear implant (CI) programmed with CIS strategy stabilized after 3 months of implant use. The data presented here may be useful as a general guideline for the programming of infants and young children and may further be of help for the identification of patients who fall outside the "average" range. OBJECTIVES: The purpose of the present study was to evaluate changes in electrical stimulation levels, i.e. threshold (T) levels, comfortable (M) levels, dynamic range (DR), and EIVs during the first 18 months of implant use, in children using the Clarion CI. MATERIALS AND METHODS: The maps of 18 pre-lingual children (mean age at implantation 4.2 years; range 1-8), using the Enhanced Bipolar 1.2 or Bipolar standard electrode with the S-Series speech processor programmed with CIS strategy, were examined at five time points: connection, and 3, 6, 12, and 18 months post-initial stimulation. T levels, M levels, DR and EIVs were analyzed according to four cochlear segments: apical, apical-medial, medial-basal, and basal. RESULTS: During the first 3 months of implant use T levels increased to some extent, whereas M levels and DR increased significantly. From 3 months and through the entire follow-up, T and M levels as well as DR were stable. EIVs of current carrying electrodes decreased significantly from connection to the 3-month visit; thereafter a stabilization of values was evident. Electrical stimulation levels and EIVs did not differ among the cochlear segments during the entire follow-up.

Adolescent↗

PubMed2006

Identification of syllables in noise: electrophysiological and behavioral correlates.

This study was designed to characterize the effect of background noise on the identification of syllables using behavioral and electrophysiological measures. Twenty normal-hearing adults (18-30 years) performed an identification task in a two-alternative forced-choice paradigm. Stimuli consisted of naturally produced syllables [da] and [ga] embedded in white noise. The noise was initiated 1000 ms before the onset of the speech stimuli in order to separate the auditory event related potentials (AERP) response to noise onset from that to the speech. Syllables were presented in quiet and in five SNRs: +15, +3, 0, -3, and -6 dB. Results show that (1) performance accuracy, d', and reaction time were affected by the noise, more so for reaction time; (2) both N1 and P3 latency were prolonged as noise levels increased, more so for P3; (3) [ga] was better identified than [da], in all noise conditions; and (4) P3 latency was longer for [da] than for [ga] for SNR 0 through -6 dB, while N1 latency was longer for [ga] than for [da] in most listening conditions. In conclusion, the unique stimuli structure utilized in this study demonstrated the effects of noise on speech recognition at both the physical and the perceptual processing levels.

Acoustic Stimulation↗

PubMed2005

Acute otitis media and mastoiditis following cochlear implantation.

OBJECTIVE: To examine the incidence of acute otitis media (AOM) and mastoiditis in children after cochlear implantation (CI) and to evaluate the role of mastoidectomy in decreasing the rate of AOM in implanted children by comparing two surgical techniques: the Posterior tympanotomy approach (MPTA, with mastoidectomy) and the Suprameatal approach (SMA, without mastoidectomy). METHODS: A retrospective study was conducted on 234 children up to 16 years of age who underwent CI between 1993 and 2003 in our department. The children were divided into two groups according to the surgical technique that had been used for the implantation: the MPTA group and the SMA group. RESULTS: Part of the children with a history of pre-implantation AOM (22 of 29 in MPTA group and 26 of 38 in SMA group) did not suffer from AOM post-CI (p=0.59), and an incidence of AOM after CI in children who did not have history of AOM prior to implantation (13 patients of MPTA group and 15 patients of SMA group) was unrelated to surgical approach (p=0.65). The incidence of pre-implantation AOM was similar for the two groups and declined after CI unrelated to performing of mastoidectomy in surgical technique. Overall, 47 children (20.1%) had post-CI AOM compared to 67 children (28.6%) who had pre-CI AOM. Mastoiditis developed in 11 children (4.7%), all 11 in the MPTA group. A subperiosteal abscess was incised and drained with the retroauricular approach in three of these children and the others were managed with intravenously administered ceftriaxone 50mg/kg/day for 3-5 consecutive days, followed by a course of oral cephalexin until there is complete clinical resolution of the effusion in the middle ear. The implants were preserved in all cases. Seven out of 11 children with mastoiditis had no history of AOM prior to implantation. CONCLUSIONS: AOM and mastoiditis represent common complications of CI that can be successfully treated with the prompt use of antibiotics. However, the subperiosteal abscess could require surgical drainage. In our opinion, the decrease of incidence of AOM in implanted children is the result of natural history of otitis media and is unrelated to the surgical approach.

Abscess↗

PubMed2005

Speech perception of children using Nucleus, Clarion or Med-El cochlear implants.

OBJECTIVE: The purpose of this study was to present speech perception achievements of implanted children using commercially available cochlear implant devices: Nucleus, Clarion or Med-El. STUDY DESIGN: A retrospective analysis. METHODS: Speech perception data of 96 hearing-impaired children: 27 with Clarion, 49 with Nucleus and 20 with Med-El were collected. Speech tests included the Hebrew Infant Toddlers Meaningful Auditory Integration Scale (HIT-MAIS) for the infants, the Hebrew Early Speech Perception (HESP) closed-set word-identification test and Hebrew Arthur Boothroyd (HAB) open-set one-syllable word recognition test were used for the older children. RESULTS: I HIT-MAIS: (1) Infants showed similar rate of progress, regardless of device. (2) Children implanted under two years of age reached performance within normal development on this test. II HAB: (1) Most children achieved open set results with mean HAB between 40 and 50%, within 1-1.5 years post implantation. (2) Linear regression analyses revealed no statistical differences between the Clarion the Nucleus and the Med-El devices on the mean final measurement of this test. (3) Age of implantation and mode of communication were significant covariate variables: (a) the younger the child is implanted the better the results and (b) oral communication prior to implantation results in better performance than sign language. CONCLUSIONS: There are no apparent differences in speech perception performance between implant devices when considering background variables. The data have important implications on the rehabilitation process of hearing impaired children with cochlear implants in relation to device selection, age at implantation and mode of communication prior to implantation.

Adolescent↗

PubMed2005

Electrical stimulation levels and electrode impedance values in children using the Med-El Combi 40+ cochlear implant: a one year follow-up.

The present study was designed to follow changes in electrical stimulation levels and electrode impedance values (EIV) in children using the Med-El Combi 40+ cochlear implant (CI) during the first 12 months of implant use. The maps of 24 prelingually deaf children implanted at a mean age of 5.9 years (range 1-15.9 years) using the TEMPO+ speech processor programmed with CIS+ strategy were examined at five time points: initial stimulation, and 1, 3, 6, and 12 months post-initial stimulation. Most comfortable levels (M) and electrode impedance values (EIV) were analyzed according to three cochlear segments: apical, medial, and basal. Results indicated a significant increase in M levels until the 3-month time point, thereafter stabilization was evident. Furthermore, M levels in the apical segment were lower than those in the medial and basal segments. EIV decreased from initial stimulation to the 3-month time point and was then stable through the study follow up. Interestingly, the finding of higher EIV in the apical segment may be attributed to the physical characteristics of the Med-El electrode. In conclusion, the pattern of stabilization of M levels found in the present study is similar to that reported for children using other devices. The data presented here may be useful as a guideline for programming M levels and monitoring EIV in infants and young children. They may further help clinicians to identify those children that fall outside the 'typical' range.

Acoustic Impedance Tests↗

PubMed2004

NRT-based versus behavioral-based MAP: a comparison of parameters and speech perception in young children.

The present study was designed to evaluate the effect of neural response telemetry (NRT)-based cochlear implant (CI) programming versus behavioral-based programming on electrical stimulation parameters (MAP) threshold (T) and comfortable (C) levels and speech perception abilities in young children, during the first year of implant use. Ten congenitally deaf children at the age of 12-39 months (mean age: 25.2 months) implanted with the Nucleus 24R(CS) CI participated in the study. The group was randomly divided into two: (1) NRT-based MAP group (n = 5) consisted of children who were programmed using intra-operative NRT measurements; (2) behavioral-based MAP group (n = 5) consisted of children who were programmed using the behavioral responses of the patients. MAP parameters as well as sound-field aided thresholds and speech perception abilities were compared between the two groups at consecutive programming sessions: 1, 3, 6, and 12 months post initial stimulation. Results indicated no significant differences among NRT-based MAPs and behavioral-based MAPs. Although MAP profiles at initial stimulation differed in the apical region, these differences decreased with time. In addition, a gradual increase of T and C levels of NRT-based MAPs as well as those of behavioral-based MAPs was evident until the 1-month time point, thereafter stabilization occurred. Sound-field aided thresholds improved with time for both groups; however, they were found to be significantly better for the NRT-based MAP group. Despite these differences, speech perception abilities were comparable among groups at 12 months post initial stimulation. NRT-based programming was found to be significantly shorter than behavioral-based programming. In conclusion, for this small group of children, our findings support the use of NRT for programming of young children during the initial period after implantation.

Acoustic Stimulation↗

PubMed2003

Changes over time in electrical stimulation levels and electrode impedance values in children using the Nucleus 24M cochlear implant.

OBJECTIVE: The present study was designed to evaluate changes in psycho-electric parameters, i.e. threshold levels, comfortable levels, dynamic range, and electrode impedance values during the 1st year post-implantation, in children using the Nucleus 24M cochlear implant system. METHODS: The maps of 25 pre-lingual children programmed with ACE strategy in Monopolar 1 + 2 mode were examined at five time points: connection, 1, 3, 6, and 12 months post-initial stimulation. Maps and electrode impedance values were analyzed according to three cochlear segments: basal, medial, and apical. RESULTS: Significant elevations of thresholds, comfortable levels, and dynamic range were found during the first few months of implant use. Specifically, threshold increased and dynamic range widened until the 3 months visit, whereas comfortable levels continued to increase until the 6 months visit, thereafter levels stabilized. Electrode impedance values decreased significantly from connection to the 1-month visit thereafter a stabilization of values was evident. In addition, thresholds and comfortable levels were found to be significantly lower in the apical segment, whereas dynamic range and electrode impedance values did not differ among the cochlear segments. CONCLUSIONS: Significant changes in psycho-electric parameters and electrode impedance values were evident during the first 6 months of implant use. Given the important role of an optimal map for speech perception, frequent programming sessions during the first few months of implant use are essential.

Acoustic Impedance Tests↗

PubMed2003

Changes over time in the psycho-electric parameters in children with cochlear implants.

Information regarding typical changes in electrical stimulation levels during different stages post-implantation in children is scarce. Clinically, this information can serve as a general guideline to the nature and frequency of these changes, and consequently help to determine programming schedules that would optimize performance with the implant. Furthermore, it may have implications for the design of cochlear implants, and for monitoring the condition of the implanted cochlea. The main goal of the present study was, therefore, to evaluate changes over time in psycho-electric parameters, i.e. threshold levels, comfortable levels, and dynamic range, in children with the Nucleus 22 cochlear implant system. The maps of 37 prelingual children were examined at five time intervals: 1, 6, 12, 18 and 24 months post-connection. Maps were analyzed according to three cochlear segments: basal, medial, and apical. The results indicated significant changes in the psycho-electric parameters during the first 2 years post-implantation. Specifically, threshold (T) levels increased significantly during the first year and stabilized during the second year, whereas comfort (C) levels and dynamic range (DR) increased significantly during the entire 2-year follow-up. In addition, psycho-electric parameters varied among the different cochlear segments, resulting in a narrower DR in the basal one. Regardless of the underlying cause for these changes, the results of the present study suggest that, in children, the stabilization of psycho-electric parameters is a prolonged, gradual process. Since psycho-electric parameters play an important role in speech perception, these findings emphasize the need for frequent programming in the first 2 years of implant use in children.

Analysis of Variance↗