Simultaneous Bilateral Implantation Research Articles

Long-Term Outcomes of Cochlear Implantation in Usher Syndrome.

Usher syndrome (USH), characterized by bilateral sensorineural hearing loss (SNHL) and retinitis pigmentosa (RP), prompts increased reliance on hearing due to progressive visual deterioration. It can be categorized into three subtypes: USH type 1 (USH1), characterized by severe to profound congenital SNHL, childhood-onset RP, and vestibular areflexia; USH type 2 (USH2), presenting with moderate to severe progressive SNHL and RP onset in the second decade, with or without vestibular dysfunction; and USH type 3 (USH3), featuring variable progressive SNHL beginning in childhood, variable RP onset, and diverse vestibular function. Previous studies evaluating cochlear implant (CI) outcomes in individuals with USH used varying or short follow-up durations, while others did not evaluate outcomes for each subtype separately. This study evaluates long-term CI performance in subjects with USH, at both short-term and long-term, considering each subtype separately. This retrospective, observational cohort study identified 36 CI recipients (53 ears) who were categorized into four different groups: early-implanted USH1 (first CI at ≤7 years of age), late-implanted USH1 (first CI at ≥8 years of age), USH2 and USH3. Phoneme scores at 65 dB SPL with CI were evaluated at 1 year, ≥2 years (mid-term), and ≥5 years postimplantation (long-term). Each subtype was analyzed separately due to the significant variability in phenotype observed among the three subtypes. Early-implanted USH1-subjects (N = 23 ears) achieved excellent long-term phoneme scores (100% [interquartile ranges {IQR} = 95 to 100]), with younger age at implantation significantly correlating with better CI outcomes. Simultaneously implanted subjects had significantly better outcomes than sequentially implanted subjects (p = 0.028). Late-implanted USH1 subjects (N = 3 ears) used CI solely for sound detection and showed a mean phoneme discrimination score of 12% (IQR = 0 to 12), while still expressing satisfaction with ambient sound detection. In the USH2 group (N = 23 ears), a long-term mean phoneme score of 85% (IQR = 81 to 95) was found. Better outcomes were associated with younger age at implantation and higher preimplantation speech perception scores. USH3-subjects (N = 7 ears) achieved a mean postimplantation phoneme score of 71% (IQR = 45 to 91). This study is currently one of the largest and most comprehensive studies evaluating CI outcomes in individuals with USH, demonstrating that overall, individuals with USH benefit from CI at both short- and long-term follow-up. Due to the considerable variability in phenotype observed among the three subtypes, each subtype was analyzed separately, resulting in smaller sample sizes. For USH1 subjects, optimal CI outcomes are expected with early simultaneous bilateral implantation. Late implantation in USH1 provides signaling function, but achieved speech recognition is insufficient for oral communication. In USH2 and USH3, favorable CI outcomes are expected, especially if individuals exhibit sufficient speech recognition with hearing aids and receive ample auditory stimulation preimplantation. Early implantation is recommended for USH2, given the progressive nature of hearing loss and concomitant severe visual impairment. In comparison with USH2, predicting outcomes in USH3 remains challenging due to the variability found. Counseling for USH2 and USH3 should highlight early implantation benefits and encourage hearing aid use.

A simultaneous post-LASIK sequential bilateral implantation of multifocal IOLs aimed at refraction correction. A clinical case

The article presents a clinical example of intraocular presbyopia correction in a patient who previously underwent laser vision correction by LASIK for mild myopia. Before the surgery, the distance VA mono- and binocular was 1.0, ADD for reading distance 40 cm +2.0 D, objective refraction sph +0.5 D cyl -0.25 D ax 980, left eye sph +0.75 D cyl -0.25 D ax 660. The patient was given a simultaneous bilateral refractive lens exchange with an implantation of a trifocal aspheric intraocular lens in the right eye and a trifocal toric aspheric intraocular lens in the left eye. We used the following IOL calculation formulas: ASCRS mean IOL power, Shammas formula, Barrett true K formula, Masket formula, Modified Masket formula, Haigis-L formula. 1 week postop: UDVA OU = 1.0, UNVA 40 cm = 1.0, UVA 70 cm = 0.7. The objective refraction OD was sph +0.0, D cyl -0.75 D ax 163, OS sph +0.25 D, cyl -0.0 D. The compliance with the modified algorithms of pre-and intraoperative behavior of the operating team, thorough preparation of the patient, careful calculation of the IOL allowed us to obtain the predictive refractive result with a high level of visual satisfaction and absence of undesirable postoperative phenomena. The patient underwent the examination with Salzburg reading desk before and after the surgery, to confirm the excellent functional results of the treatment. Despite the fact that simultaneous same day IOL implantation in both eyes, especially in eyes with previously operated corneas, is still disputable, the above case confirms that with modern equipment, precise multi formula calculation, and ample experience help achieve excellent functional and refractive results.

Clinical experience: Simultaneous bilateral Osia implantation in children with microtia.

Clinical experience: Simultaneous bilateral Osia implantation in children with microtia.

Age and Incidence of Cochlear Implantation in the Pediatric Population With Congenital Bilateral Profound Hearing Loss.

The current study characterizes age and incidence of cochlear implantation among qualifying children with congenital bilateral profound hearing loss in the U.S. Deidentified cochlear implantation data were acquired from prospectively collected patient registries from two cochlear implant (CI) manufacturers (Cochlear Americas and Advanced Bionics). Children <36 months old were assumed to have congenital bilateral profound sensorineural hearing loss. U.S. CI centers. Children <36 months old who received CIs. Cochlear implantation. Age at implantation and incidence. A total of 4,236 children <36 months old underwent cochlear implantation from 2015 to 2019. The median age at implantation was 16 months (interquartile range, 12-24 mo) and did not change significantly during the 5-year study period ( p = 0.09). Patients residing closer to CI centers ( p = 0.03) and treated at higher-volume centers ( p = 0.008) underwent implantation at a younger age. Bilateral simultaneous implantation increased from 38% to 53% of CI surgeries in 2015 and 2019, respectively. Children who received bilateral simultaneous CIs were younger compared with those receiving unilateral or bilateral sequential CIs (median, 14 versus 18 mo; p < 0.001). The incidence of cochlear implantation increased from 7,648 per 100,000 person-years in 2015 to 9,344 in 2019 ( p < 0.001). Although the incidence of pediatric CI recipients and the frequency of bilateral simultaneous implantation increased over the study period, age at implantation did not change significantly and far exceeded current Food and Drug Administration (9 mo) and American Academy of Otolaryngology and Head and Neck Surgery position statement (6-12 mo) guidelines.

Development of Sound Localization in Infants and Young Children with Cochlear Implants.

Cochlear implantation as a treatment for severe-to-profound hearing loss allows children to develop hearing, speech, and language in many cases. However, cochlear implants are generally provided beyond the infant period and outcomes are assessed after years of implant use, making comparison with normal development difficult. The aim was to study whether the rate of improvement of horizontal localization accuracy in children with bilateral implants is similar to children with normal hearing. A convenience sample of 20 children with a median age at simultaneous bilateral implantation = 0.58 years (0.42-2.3 years) participated in this cohort study. Longitudinal follow-up of sound localization accuracy for an average of ≈1 year generated 42 observations at a mean age = 1.5 years (0.58-3.6 years). The rate of development was compared to historical control groups including children with normal hearing and with relatively late bilateral implantation (≈4 years of age). There was a significant main effect of time with bilateral implants on localization accuracy (slope = 0.21/year, R2 = 0.25, F = 13.6, p &lt; 0.001, n = 42). No differences between slopes (F = 0.30, p = 0.58) or correlation coefficients (Cohen's q = 0.28, p = 0.45) existed when comparing children with implants and normal hearing (slope = 0.16/year since birth, p = 0.015, n = 12). The rate of development was identical to children implanted late. Results suggest that early bilateral implantation in children with severe-to-profound hearing loss allows development of sound localization at a similar age to children with normal hearing. Similar rates in children with early and late implantation and normal hearing suggest an intrinsic mechanism for the development of horizontal sound localization abilities.

Long-term outcomes of retrospective case series of middle ear implantation with Vibrant Soundbridge in children with congenital aural atresia.

to assess audiological performance in quiet and noise, quality of life and side effects of Vibrant Soundbridge (VSB) in children with congenital aural atresia (CAA). A retrospective study including consecutive patients with unilateral or bilateral CAA implanted with VSB from 2009 to 2020 in a tertiary referral centre. 18 patients with CAA and a present stapes were included (3 simultaneous bilateral VSB implants) and 21 ears: 17 VSB were attached to the short incus process, and four to the stapes. Age at implantation ranged from 4.7 to 15.8years. Average follow-up was 6.5years (± 3.7years). In unilateral VSB, air conduction pure tone average (ACPTA) thresholds increased from 75.3 ± 15.2 to 32.6 ± 8.3dB post-operatively (VSB activated) (n = 15; p < 0.01). The speech reception threshold (SRT) and the word recognition score (WRS) were significantly improved from 81.5 ± 10.4 to 43.9 ± 7.6dB and 0% to 84.8 ± 8.5% postoperatively (n = 15; p < 0.01). The signal to noise ratio (SNR) was significantly improved from 2.1 ± 2.9dB VSB inactivated to 0.3 ± 2.7dB VSB activated (n = 15; p < 0.01). There was no significant difference in performance according to floating mass transducer (FMT) placement. 5/15 children were non-users at last follow-up in unilateral VSB and 0/3 in bilateral. CAA ears with VSB activated had a significant improvement of ACPTA, WRS, SRT and SNR. A third of patients with unilateral CAA became non-users at last follow-up. The main challenge is to target the indications for the implantation of the VSB to avoid its discontinuation.

Simultaneous Bilateral Bone Bridge Implantation in a Two-Year-Old Child with Atresia of the External Auditory canal: A Case Report

Introduction: Active transcutaneous bone conduction implants are indicated for mild to moderate conductive or mixed hearing loss (intact inner ear and auditory nerve) for subjects 5 years or older. The aim of the here presented study was to share our results with the Bonebridge in a child aged 2 years at time of surgery. Especially the new generation of the implant being half of the size, a re-evaluation of the given indication for children 5 years or older is highly recommended.

Changes in Vestibular Function Following Pediatric Cochlear Implantation: a Prospective Study.

Given the close interconnection between the auditory and vestibular end organs, the increasingly broad application of (bilateral) cochlear implantation (CI) in children raises concern about its impact on the vestibular function. Unfortunately, literature on this matter is inconclusive and subject to several limitations. Therefore, this study aimed to elucidate the impact of pediatric CI on the vestibular function in a large sample of children, representative for the current CI population. Fifty hearing-impaired children followed in the Ghent University Hospital were included in this prospective study. Twenty-seven patients underwent unilateral CI, and 23 were bilaterally implanted (9 sequentially, 14 simultaneously), adding up to 73 implanted ears. Children's median age at first implantation was 29 (range 8 to 194) months. Vestibular assessment was scheduled on average 2.8 months (SD: 3.6) before and 4.6 (SD: 4.0) months after implantation and consisted of video Head Impulse Testing of the lateral semicircular canals, rotatory testing (0.16, 0.04, and 0.01 Hz) and cervical vestibular evoked myogenic potential (cVEMP) testing with bone conduction stimulation. Caloric testing was added in children older than 3 years of age. Overall, group analysis in our sample of 73 CI-ears did not reveal any significant impact on the vestibular function, except for a significantly shortened ipsilateral N1 latency of the cVEMP responses (p = 0.027) after CI. Complete ipsilateral loss of function after implantation was seen in 5% (3/54) of all CI-ears on the video head impulse testing, in 0% (0/10) on the caloric test and in 2% (1/52) on the cVEMP, notably all patients deafened by a congenital cytomegalovirus infection. The impact of CI on the vestibular function in our dataset was limited. Therefore, the many advantages of simultaneous bilateral implantation may outweigh the risk for vestibular damage postoperatively. However, the impact on the vestibular function may be dependent on various factors (e.g., etiology of the hearing loss), and the clinical outcome is still difficult to predict. Vestibular assessment remains thus an important aspect in the pediatric CI population; first because the vestibular function should be considered in the decision-making process on (simultaneous or sequential bilateral) CI and second because it is essential to reveal a possible additional sensory deficit, allowing an opportunity for rehabilitation to improve the overall outcome of these children.

Maturation process of regenerated tissues after single-stage simultaneous autologous particulated cartilage implantation and open wedge high tibial osteotomy for articular cartilage defects with medial osteoarthritis of bilateral knees: a case report

BackgroundOpen wedge high tibial osteotomy (OWHTO) is an effective treatment option for young and middle-aged active patients with medial unicompartmental knee osteoarthritis (OA). In addition, particulated cartilage implantation has been developed as a simple procedure for cartilage regeneration. Thus, to improve the OWHTO outcomes, a single-stage, simultaneous bilateral knee arthroscopic particulated cartilage implantation with OWHTO was performed.Case presentationA 60-year-old male patient presented with severe bilateral knee pain, with grade 2 varus knee OA of the Kellgren–Lawrence classification. Primary arthroscopic evaluations based on the International Cartilage Repair Society grading system showed grade 3c articular cartilage defects of 1.5 cm in diameter at the center of the bilateral medial femoral condyles. Following bilateral OWHTO, the healthy cartilage tissue was harvested from the lateral wall of the unilateral femoral intercondylar notch and minced with the cartilage processor. Then, subchondral drillings and cartilage fragment implantations into the bilateral defects were performed arthroscopically. One year postsurgery, second-look arthroscopy findings revealed that the defects were filled with cartilage-like tissues. The maturation process of the regenerated tissues was confirmed with T2 mapping magnetic resonance imaging during the 3-year follow-up period. The patient could walk without a cane, and all Knee Injury and Osteoarthritis Outcome Score parameters were improved without any correction loss in 3 years.ConclusionsThis is the first report to evaluate the maturation process of the implanted particulated cartilage tissue with T2 mapping magnetic resonance imaging for 3 years. The effect of chondral resurfacing procedure with OWHTO remains unclear; however, the implantation of arthroscopic particulated cartilage fragments is a single-stage and less-invasive procedure. This treatment could regenerate cartilage-like tissue in the present case. Therefore, this additional procedure could potentially improve the long-term outcomes of OWHTO.

Comparison of Outcomes in Unilateral and Bilateral Pediatric Cochlear Implants: Our Experience.

The aim of our study is to compare the outcomes in unilateral and bilateral cochlear implants in pediatric age and also between simultaneous and sequential cochlear implant surgery. This retrospective study was carried out with 83 children aged between 12months to 2.5years which included 41 children with bilateral Cochlear implants and 42 with unilateral implants. Out of these 41 children, 21 were simultaneous and 20 were sequential cochlear implant. All the children were operated at civil hospital Gandhinagar, Gujarat, India. CAP, SIR, localization, traffic noise and speech in noise scores were assessed at regular intervals over the period of 4years. Also the drug administration time, surgical time, operating room time were assessed for simultaneous and sequential cochlear implant surgery. Children with bilateral simultaneous implants fared significantly better with CAP, SIR, localization, speech noise and traffic noise scores than sequential bilateral implants and unilateral implants with a significant difference of means t tests between the two groups. Simultaneous cochlear implant surgery is associated with reduced surgical time, operating room time, it shortens the total in patient stay. There is less of drug administration and bilateral ones are stimulated simultaneously. Bilateral cochlear implants perform better with respect to auditory perception skills and spontaneous speech when compared with unilateral implants, but simultaneous surgery is better and safe option for pediatric cochlear implantation.

Simultaneous bilateral cochlear implantation in children aged 12‒18 months is safe and can be performed using standard cochlear implant surgical techniques

Simultaneous bilateral cochlear implantation is often seen as the gold-standard intervention for many people with bilateral deafness. However, this intervention is not as commonly performed in China. This paper presents the surgical technique and the peri- and postoperative safety results from simultaneous bilateral implantation and compares them with those from sequential bilateral implantation. Twenty nine children (aged 12‒18months) met the inclusion/exclusion criteria and took part in this study. 10 participants received a unilateral cochlear implantation; 19 participants received simultaneous bilateral cochlear implantation. The same standard surgical technique (transmastoid facial recess approach with round window insertion) was used in all implantations. Safety was assessed via monitoring peri- and postoperative adverse events. The helpfulness of select surgical tools was assessed via questionnaire. No adverse events were reported for any participants. All queried surgical tools were helpful in all 244 recorded responses. Simultaneous bilateral cochlear implantation can be performed using the same surgical technique as unilateral implantation and poses no increased safety risk for children aged 1‒2years.

Data logging variables and speech perception in prelingually deafened pediatric cochlear implant users

ObjectivesTo investigate the relationship among objectively gathered data logging measurements, patient-related variables, and speech recognition performance of pediatric CI users. Methods and materialsThirty-two prelingually implanted children who have the ability to perform word discrimination test were included in this study. To reveal the relationship between speech perception abilities and auditory exposure, seven data logging variables were analyzed: “on-air,” “off-air,” “coil-off,” “speech,” “speech in noise,” “music” and “noise. In addition, implantation age (months) and CI usage duration (months) were taken into account. Finally, it was investigated the differences between unilateral, sequential bilateral, and simultaneous bilateral CI users in terms of all study variables. ResultsThe average on-air time ranged between 10.52 and 12.30 in the groups. In the case of sequential implantation, smaller on-air and higher coil off values were observed with the second CI. In the case of simultaneous bilateral implantation, data logging measurements were almost the same in both implants. WRS was significantly correlated (p < 0.05) with on-air time (r = 0.62), coil-off count (r = −0.48), chronological age (r = 0.48), and CI duration (r = 0.44). Multiple linear regression model was fit to predict the WRS, with on-air time, CI duration, and chronological age as predictors. ConclusionsThe critical importance of early intervention and long-term use of CI is well-established in the literature and is also corroborated by our findings. However, the key findings of the present study are that consistent CI use and the quality of daily listening environment also exerted a major and positive effect on the speech recognition performance of pediatric CI users. Therefore, during the monitoring of pediatric CI recipients, it is important to know the device usage data in order to detect problems in the early stages after CI.

Subtotal Petrosectomy in Cochlear Implant Surgery: Our Experience.

Subtotal petrosectomy (SP) with cochlear implant (CI) is required in certain specific situations in the management of patients who are candidates for cochlear implants. To study and review the indications, surgical issues, and complications of this procedure. Retrospective review of all patients who underwent subtotal petrosectomy with cochlear implant during the period January 2010-December 2016 at a tertiary care and referral centre. 19 patients underwent 20 subtotal petrosectomy with cochlear implant during this period. One patient had simultaneous bilateral implantation. The indications were previous mastoid cavity in 7 patients, 5 patients had chronic otitis media, inner ear malformations in 3,ossified cochlea in 3 and unfavourable anatomy in 2 patients. Fat or musculoperiosteal flaps were used to obliterate the cavity. Ninety percent of patients underwent single stage surgery and ten percent underwent two stage procedure.Complications were seen in three patients (15%). SP helps in isolating the cavity from external environment after removal of disease, improves the exposure and access, reduces risk of infection and cerebrospinal fluid (CSF) leaks and facilitates CI. Meticulous surgical technique will reduce the complications and long term follow up is needed to detect entrapped cholesteatoma. Subtotal petrosectomy with blind sac closure of external ear canal is required in certain specific situations. It is a safe and effective surgery with acceptable rate of complications.

Qualification of unilateral cochlear implant recipients for a second device.

Although it is recommended to perform cochlear implantation in both ears at the same time for management of profound hearing loss in children, many centers prefer to perform sequential implantation. There are many reasons as to why a simultaneous bilateral implantation is not commonly accepted and performed. The major risk is the possibility of bilateral vestibular organ impairment. However, it is beyond doubt that children who received the first implant should be given a chance for binaural hearing and associated benefits. In the literature, there are no homogenous criteria for bilateral implantation, and it is hard to find uniform and convincing algorithms for second cochlear implantation. The aim of this study is an attempt to identify a safe way of qualifying for second cochlear implantation in children. Forty children with one cochlear implant were qualified for the second implantation. During qualification, the following were taken into account: time of the first implantation, audiometry results, use of the hearing aid in the ear without an implant and benefit of the device, speech and hearing development, and vestibular organ function. R esults: Fifteen out of forty children (38%) were qualified for the second implantation. In 35% of children, the decision was delayed with possible second implantation in the future. Eleven children (27%) were disqualified from the second surgery. During evaluation according to the protocol presented in our study, 38% of children with a single cochlear implant were qualified for the second implantation with a chance for an optimal development and effective use of the second cochlear implant. We are convinced that sequential implantation with a short interval between surgeries and with an examination of the vestibular organ, hearing and speech development as well as an assessment of potential benefits from the second implant (bimodal stimulation) before the second implantation is the safest and most beneficial solution for children with severe hearing loss.

Cortical Processing of Level Cues for Spatial Hearing is Impaired in Children with Prelingual Deafness Despite Early Bilateral Access to Sound.

Bilateral cochlear implantation aims to restore binaural hearing, important for spatial hearing, to children who are deaf. Improvements over unilateral implant use are attributed largely to the detection of interaural level differences (ILDs) but emerging evidence of impaired sound localization and binaural fusion suggest that these binaural cues are abnormally coded by the auditory system. We used multichannel electroencephalography (EEG) to assess cortical responses to ILDs in two groups: 13 children who received early bilateral cochlear implants (CIs) simultaneously, known to protect the developing auditory cortices from unilaterally driven reorganization, and 15 age matched peers with normal hearing. EEG source analyses indicated a dominance of right auditory cortex in both groups. Expected reductions in activity to ipsilaterally weighted ILDs were evident in the right hemisphere of children with normal hearing. By contrast, cortical activity in children with CIs showed: (1) limited ILD sensitivity in either cortical hemisphere, (2) limited correlation with reliable behavioral right-left lateralization of ILDs (in 10/12 CI users), and (3) deficits in parieto-occipital areas and the cerebellum. Thus, expected cortical ILD coding develops with normal hearing but is affected by developmental deafness despite early and simultaneous bilateral implantation. Findings suggest that impoverished fidelity of ILDs in independently functioning CIs may be impeding development of cortical ILD sensitivity in children who are deaf but do not altogether limit benefits of listening with bilateral CIs. Future efforts to provide consistent/accurate ILDs through auditory prostheses including CIs could improve binaural hearing for children with hearing loss.

Cost-effectiveness of pediatric bilateral cochlear implantation in Spain.

To determine the incremental cost-effectiveness of bilateral versus unilateral cochlear implantation for 1-year-old children suffering from bilateral sensorineural severe to profound hearing loss from the perspective of the Spanish public health system. Cost-utility analysis. We conducted a general-population survey to estimate the quality-of-life increase contributed by the second implant. We built a Markov influence diagram and evaluated it for a life-long time horizon with a 3% discount rate in the base case. The incremental cost-effectiveness ratio of simultaneous bilateral implantation with respect to unilateral implantation for 1-year-old children with severe to profound deafness is €10,323 per quality-adjusted life year (QALY). For sequential bilateral implantation, it rises to €11,733/QALY. Both options are cost-effective for the Spanish health system, whose willingness to pay is estimated at around €30,000/QALY. The probabilistic sensitivity analysis shows that the probability of bilateral implantation being cost-effective reaches 100% for that cost-effectiveness threshold. Bilateral implantation is clearly cost-effective for the population considered. If possible, it should be done simultaneously (i.e., in one surgical operation), because it is as safe and effective as sequential implantation, and saves costs for the system and for users and their families. Sequential implantation is also cost-effective for children who have received the first implant recently, but it is difficult to determine when it ceases to be so because of the lack of detailed data. These results are specific for Spain, but the model can easily be adapted to other countries. 2C. Laryngoscope, 127:2866-2872, 2017.

A Comparison of Unilateral Deep Brain Stimulation (DBS), Simultaneous Bilateral DBS, and Staged Bilateral DBS Lead Accuracies

Accuracy of lead placement within the brain can affect the outcome of deep brain stimulation (DBS) surgery. Whether performing unilateral lead implantation, simultaneous bilateral lead implantation, or staged bilateral lead implantation affects accuracy has not yet been assessed. We compare lead placement errors to evaluate whether one approach affords greater lead accuracy. We retrospectively reviewed 205 leads placed in 125 DBS surgeries. The accuracy of lead placement, defined by differences in x, y, and z coordinates and error vector magnitudes, was compared between three surgery groups: unilateral leads, bilateral leads placed simultaneously, and bilateral leads placed in staged surgeries. We also compared accuracies between first and second leads within each bilateral cohort and between second leads of the bilateral cohorts. Finally, we examined the effect of target and age on accuracy. The accuracy of lead placement was comparable among unilateral, simultaneous bilateral, and staged bilateral leads. Timing of placement of the second lead in bilateral cases was not found to affect accuracy. The mean number of microelectrode trajectories was greater for first leads in simultaneous bilateral DBS (p = 0.032). No significant correlation between either age or target and accuracy was found. Although there may be other important reasons for performing DBS in a staged fashion, our study finds that neither laterality nor timing of second lead placement, patient age, or target site have significant impact on DBS lead accuracy, a finding that indicates with appropriate approach selection based on patient factors, accuracy does not have to be significantly compromised.

Management and outcomes of cochlear implantation in patients with congenital cytomegalovirus (cCMV)-related deafness

Objective: Congenital Cytomegalovirus (cCMV) is a well-defined cause for neonatal mortality and morbidity, particularly sensorineural hearing loss and other neurodevelopmental disruption. We present a retrospective study which provides an overview of the assessment and preoperative work-up for patients diagnosed with cCMV and their cochlear implant (CI) outcomes.Method: This was a retrospective case series study of all children with a confirmed diagnosis of cCMV who underwent cochlear implantation at St Thomas’ Hospital from 2003 to 2015. Data were collected on the preoperative audiology, imaging findings, and neurological assessment. CI outcomes were measured using the Speech Intelligibility Rating (SIR), Category of Auditory Performance (CAP), and Infant-Toddler Meaningful Auditory Integration Scale (IT-MAIS).Results: Eleven patients underwent cochlear implantation, 45% had severe-to-profound hearing loss, and 55% had bilateral profound hearing loss. The mean age at initial assessment was 2.1 years (median 1.7, range 0.6–7.5) and the mean age of implantation was 4.0 years (median 2.5, range 0.9–11.8). The mean length of follow-up was 4.8 years (median 2.3, range 1.5–14). Six patients had bilateral simultaneous implantation (55%), four bilateral sequential (36%), and one unilateral (9%). Nine patients had white matter changes on magnetic resonance imaging, largely in the periventricular and cortical regions. Of the 11 patients, 4 (36%) had associated neurological comorbidities and 3 (27%) had additional neurocognitive developmental delay of varying severity. The majority of patients showed improvement in auditory outcomes. No statistically significant correlation was found between age of implantation, neurocognitive, and neurological comorbidities or length of follow-up and hearing outcomes.Conclusion: While the overall outcomes were mixed, most children in our cohort were found to benefit from cochlear implantation. Our data also highlight the significant neurodevelopmental comorbidities associated with cCMV and their negative impact on CI outcomes. With the recent advances in medical treatment, this underlines the importance of multidisciplinary management of these patients.

Cortical Representation of Interaural Time Difference Is Impaired by Deafness in Development: Evidence from Children with Early Long-term Access to Sound through Bilateral Cochlear Implants Provided Simultaneously.

Accurate use of interaural time differences (ITDs) for spatial hearing may require access to bilateral auditory input during sensitive periods in human development. Providing bilateral cochlear implants (CIs) simultaneously promotes symmetrical development of bilateral auditory pathways but does not support normal ITD sensitivity. Thus, although binaural interactions are established by bilateral CIs in the auditory brainstem, potential deficits in cortical processing of ITDs remain. Cortical ITD processing in children with simultaneous bilateral CIs and normal hearing with similar time-in-sound was explored in the present study. Cortical activity evoked by bilateral stimuli with varying ITDs (0, ±0.4, ±1 ms) was recorded using multichannel electroencephalography. Source analyses indicated dominant activity in the right auditory cortex in both groups but limited ITD processing in children with bilateral CIs. In normal-hearing children, adult-like processing patterns were found underlying the immature P1 (∼100 ms) response peak with reduced activity in the auditory cortex ipsilateral to the leading ITD. Further, the left cortex showed a stronger preference than the right cortex for stimuli leading from the contralateral hemifield. By contrast, children with CIs demonstrated reduced ITD-related changes in both auditory cortices. Decreased parieto-occipital activity, possibly involved in spatial processing, was also revealed in children with CIs. Thus, simultaneous bilateral implantation in young children maintains right cortical dominance during binaural processing but does not fully overcome effects of deafness using present CI devices. Protection of bilateral pathways through simultaneous implantation might be capitalized for ITD processing with signal processing advances, which more consistently represent binaural timing cues.SIGNIFICANCE STATEMENT Multichannel electroencephalography demonstrated impairment of binaural processing in children who are deaf despite early access to bilateral auditory input by first finding that foundations for binaural hearing are normally established during early stages of cortical development. Although 4- to 7-year-old children with normal hearing had immature cortical responses, adult patterns in cortical coding of binaural timing cues were measured. Second, children receiving two cochlear implants in the same surgery maintained normal-like input from both ears, but this did not support significant effects of binaural timing cues in either auditory cortex. Deficits in parieto-occiptal areas further suggested impairment in spatial processing. Results indicate that cochlear implants working independently in each ear do not fully overcome deafness-related binaural processing deficits, even after long-term experience.

United Kingdom national paediatric bilateral project: Demographics and results of localization and speech perception testing

Objectives: To assess longitudinal outcomes in a large and varied population of children receiving bilateral cochlear implants both simultaneously and sequentially.Methods: This observational non-randomized service evaluation collected localization and speech recognition in noise data from simultaneously and sequentially implanted children at four time points: before bilateral cochlear implants or before the sequential implant, 1 year, 2 years, and 3 years after bilateral implants. No inclusion criteria were applied, so children with additional difficulties, cochleovestibular anomalies, varying educational placements, 23 different home languages, a full range of outcomes and varying device use were included.Results: 1001 children were included: 465 implanted simultaneously and 536 sequentially, representing just over 50% of children receiving bilateral implants in the UK in this period. In simultaneously implanted children the median age at implant was 2.1 years; 7% were implanted at less than 1 year of age. In sequentially implanted children the interval between implants ranged from 0.1 to 14.5 years. Children with simultaneous bilateral implants localized better than those with one implant. On average children receiving a second (sequential) cochlear implant showed improvement in localization and listening in background noise after 1 year of bilateral listening. The interval between sequential implants had no effect on localization improvement although a smaller interval gave more improvement in speech recognition in noise. Children with sequential implants on average were able to use their second device to obtain spatial release from masking after 2 years of bilateral listening. Although ranges were large, bilateral cochlear implants on average offered an improvement in localization and speech perception in noise over unilateral implants.Conclusion: These data represent the diverse population of children with bilateral cochlear implants in the UK from 2010 to 2012. Predictions of outcomes for individual patients are not possible from these data. However, there are no indications to preclude children with long inter-implant interval having the chance of a second cochlear implant.