Age-related changes in auditory perception. Hearing loss in the elderly: aging ear or aging brain?

Hearing loss in the elderly is a very common disease: it is estimated to affect up to a third of the population aged 65 years or more, and 50% of people over 75 years old. There is a growing amount of data concerning the association between hearing loss and cognitive decline. Various possible mechanisms at the basis of this association have been proposed, such as the "common cause hypothesis," the "cascade hypothesis," and the "cognitive load hypothesis."Critically reviewing the data is essential to highlight the features of the relationship between hearing loss and cognitive decline. Most of the hearing tests available should take into account that dementia or even just mild cognitive impairment (MCI) may lead to poor performance during examination. On the other hand, clinicians should also remember that tests used to assess cognitive function require an adequate hearing capacity.In this article we propose to analyze current diagnostic tests, treatment options, auditory processing, and rehabilitation strategies for hearing loss in the elderly in order to facilitate the management of this handicap in this fragile population.

Does social distancing impact pediatric upper airway infections? An observational controlled study and a brief literature review.

PURPOSE: SARS-CoV-2 pandemic has reduced social interaction even among children. The objective of the study was to assess the role of social distancing in the course of common pediatric upper airway recurrent diseases. MATERIALS AND METHODS: Patients aged ≤14 years with at least one ENT-related clinical condition were retrospectively recruited. All patients had two outpatient evaluations in the same period (April - September): the control group had the first evaluation in 2018 and second in 2019, whereas the case group had the first evaluation in 2019 and second in 2020. Patients of each group were individually compared between their two visits and deemed improved/unchanged/worsened for each specific ENT condition. The percentage of children improved/unchanged/worsened were then collectively compared between the two groups for each condition. RESULTS: Patients who experienced social distancing presented a significantly higher improvement rate than controls for recurrent acute otitis media episodes (35.1 % vs. 10.8 %; Fisher's exact test p = 0.033) and for tympanogram type (54.5 % vs. 11.1 %, Fisher's exact test p = 0.009). CONCLUSIONS: The anti-contagion social restrictions decreased the prevalence of middle ear infections and effusion in children. Further studies on larger cohorts are required to better elucidate these findings.

Cochlear implant in vestibular schwannomas: long-term outcomes and critical analysis of indications.

PURPOSE: To describe our institutional experience in cochlear implantation after vestibular schwannoma (VS) resection, and compare the audiological outcomes between sporadic and neurofibromatosis type 2 (NF2) VS sub-cohorts of patients, and in relation to preoperative contralateral hearing. METHODS: Seventeen patients (8 sporadic and 9 NF2-associated VSs) who had undergone VS resection and cochlear implant (CI) were analyzed retrospectively. Audiological outcomes at 24 months were correlated with preoperative clinical variables. The results according to VS type (sporadic vs. NF2-associated) and contralateral hearing (impaired vs. normal) were compared. RESULTS: Fourteen CIs were actively used by the patients (77.8%). Twenty-four months after CI activation, the median postoperative PTA (pure tone average) was 45.6 dB nHL and a measurable WRS (Word Recognition Score) was achieved by 44.4% of patients (median WRS = 40%). The median postoperative PTA in the implanted ear resulted better in the group with an impaired contralateral hearing (36.3 dB nHL vs. 78.8 dB nHL, p = 0.019). Good preoperative contralateral hearing status (A-B classes of AAO-HNS) was a negative prognostic factor for CI performance on open-set discrimination (OR = 28.0, 95% CI 2.07-379.25, p = 0.012). CONCLUSIONS: CI is a viable rehabilitative option for patients with sporadic or NF2-associated VS. A good contralateral hearing adversely affects CI outcome and should be taken into consideration for patients' selection and rehabilitation programs.

How great is the negative impact of masking and social distancing and how can we enhance communication skills in the elderly people?

During COVID-19 pandemic, protective measures such as social distancing and face masks posed a challenge in daily communication, in this context the elderly are one of the most at risk categories as widely exposed to hearing loss. This article focuses on how the COVID-19 pandemic affected verbal communication, especially on those people that even in normal conditions present an increased difficulty in speech perception. Special attention has been paid to hearing aids and cochlear implant users, these devices indeed can be affected by a speech intelligibility reduction and could be uncomfortable if used together with face masks. Possible alternatives and solutions will be proposed to reduce the negative impacts of face coverings on communication, to enhance speech intelligibility and to manage wearability of hearing rehabilitation devices.

Video-nystagmographic evidence in more than 700 consecutive cases of road traffic whiplash injury.

PURPOSE: Whiplash injury is a frequent traumatic lesion occurring mainly in road accidents, which may also cause dizziness severe enough to impact everyday life. Vestibular examination is routinely performed on these patients, although the role of the neuro-otologist is still not clearly defined. The main endpoint of this study was to describe the videonystagmography (VNG) evidence in a large cohort of patients who underwent road traffic whiplash injury. METHODS: 717 consecutive patients who reported whiplash-associated disorders due to a road traffic accident underwent clinical examination and VNG. RESULTS: Patients with saccadic test latency anomalies more frequently complained of vertigo, nausea and cochlear symptoms after trauma (p = 0.031, 0.028 and 0.006), while patients with bilateral vestibular weakness at caloric stimulation more often displayed neck pain after trauma (p = 0.005). Patients complaining of positional or cochlear symptoms or with accuracy anomalies at the saccadic test were significantly older than those with no positional, no cochlear symptoms and without accuracy anomalies (p = 0.022, p = 0.034 and p = 0.001). Patients with bilateral vestibular hypofunction were significantly younger (p < 0.001). CONCLUSIONS: VNG evidence, particularly vestibular function and saccadic tests, may be related to damage in the cervical region due to whiplash trauma. These findings suggest that neuro-otologic examination may play a role in properly identifying those who suffer damage caused by whiplash trauma, and in characterizing the severity and prognosis of whiplash-associated disorders.

Temporal bone carcinoma: testing the prognostic value of a novel clinical and histological scoring system.

PURPOSE: Our group recently proposed the novel Padova prognostic scoring system for temporal bone carcinoma (TBSCC) that considers: the revised Pittsburgh staging system; radiological dura mater involvement; non-anterior spread (medial, inferior or posterior into the temporal bone and skull base) of T4 tumors; and histological grade. The aim of the present study was to validate this prognostic TBSCC scoring system in a case series selected from the literature. METHODS: A search was run to identify studies on TBSCC reporting the variables included in our score for each patient. Then our system was applied to the data extracted. RESULTS: Only two published investigations reported all the clinical and pathological data required for our scoring system. In one series from the Gruppo Otologico in Piacenza (Italy), a significantly higher recurrence rate (p = 0.008), shorter disease-free survival (DFS) (p = 0.001), higher disease-specific mortality (DSM) (p = 0.006), and shorter disease-specific survival (DSS) (p = 0.004) were associated with scores ≥ 5. Receiver operating curve (ROC) analysis showed an AUC of 0.804 for TBSCC recurrence, and 0.832 for DSM. In a series from Kyushu University Hospital (Japan), a significantly higher DSM (p = 0.018) and shorter DSS (p = 0.021) were associated with scores ≥ 5. ROC analysis showed an AUC of 0.812 for tumor relapse and 0.790 for DSM. CONCLUSION: Our TBSCC Padova scoring system confirmed its validity when applied to the only two international TBSCC series providing the required data. These preliminary results need to be confirmed in a multi-center prospective setting.

Road traffic whiplash injury in the elderly: Clinical and video-nystagmographic features.

PURPOSE: Whiplash is a type of trauma typically caused by a rear end collision in a road accident. About one in two patients who experience whiplash report dizziness and balance problems, which can severely affect their activities in daily life. In industrialized countries, the number of elderly people with a driving license has increased in recent years. The aims of the present study were to describe the video-nystagmographic features in a consecutive series of elderly patients experiencing whiplash injury in a road accident, comparing them with similar injuries in a group of young adults. METHODS: Twenty-seven patients aged 65 years or more and a control group of 32 young adults between 18 and 21 years old were retrospectively selected. All patients underwent oto-vestibular assessment and video-nystagmography. RESULTS: After whiplash trauma, vertigo was more common in elderly patients with decreased peak velocity during the saccadic ocular motricity test (p = 0.017) and with evidence of bilateral vestibular hypofunction after caloric stimulation (p = 0.033). Comparing the two age groups, neck pain after the trauma was reported significantly more by young adults (p = 0.003), who also showed more frequently bilateral vestibular hypofunction (p = 0.025). CONCLUSION: Clinical and instrumental findings seem to support the hypothesis of a functional lesion to the brainstem regions after a whiplash injury. There is an undeniable need, however, for tools capable of objectively assessing the functional or anatomical damage resulting from whiplash-associated disorders, for both clinical and medico-legal reasons.

Cochlear implant outcomes in the elderly: a uni- and multivariate analyses of prognostic factors.

PURPOSE: To assess preoperative features that could predict the audiological outcome after cochlear implantation in the elderly, in terms of pure tone audiometry, speech audiometry, and speech perception performance. METHODS: All available records of patients with cochlear implants aged 65 or more at the time of their implantation at our Institution were reviewed (50 patients, mean age 70.76 ± 4.03 years), recording preoperative clinical features. Pure tone audiometry, speech audiometry, and speech perception performance 1 year after cochlear implant activation and fitting were used as outcome measures. RESULTS: No statistically significant association emerged between clinical features and pure tone audiometry. On univariate analysis, progressive sensorineural hearing loss of unknown origin was associated with a better outcome in terms of speech audiometry and speech perception performance (p = 0.035 and p = 0.033, respectively). On multivariate analysis, progressive sensorineural hearing loss retained its independent prognostic significance in terms of speech perception performance (p = 0.042). The discriminatory power of a two-variable panel (age and etiology of hearing loss) featured an AUC (ROC) of 0.738 (an acceptable discriminatory power according to the Hosmer-Lemeshow scale). CONCLUSIONS: A progressive sensorineural hearing loss of unknown origin was associated with a better outcome in terms of speech perception in the elderly in our case study. Further features that can predict audiological outcome achievable with cochlear implants in the elderly are desirable to perform adequate counselling and rehabilitation programs.

Temporal bone carcinoma: a first glance beyond the conventional clinical and pathological prognostic factors.

Temporal bone squamous cell carcinoma (TBSCC) is an uncommon, aggressive malignancy with a poor prognosis in advanced cases. The dismal outcome is partially related to: the lack of reliable clinical or pathological prognostic factors and the largely unstandardized surgical and integrated treatments adopted. There is an undeniable need for novel diagnostic/therapeutic strategies to improve the prognosis. The purpose of this critical review was to explore the level of available knowledge concerning the molecular markers involved in the biology of TBSCC that have a prognostic potential. The Pub-Med and Scopus electronic databases were searched without publication date limits for studies investigating molecular markers in cohorts of patients with primary TBSCC. The search terms used were: "temporal bone cancer", "temporal bone carcinoma", "temporal bone malignancy", "ear cancer", "ear carcinoma", and "ear malignancy". We decided preliminarily not to consider series with less than five cases. Nine retrospective case series of TBSCC were found in which different analytical techniques had been used to study the role of several biomarkers (HPV, vimentin, transforming growth factor ß, CD105, RECK, matrix metalloproteinase-9, MASPIN, EBV, p16, TP53 mutation, pSTAT3, relaxin-2). CD105 expression (in tumor vessel endothelial cells) and MASPIN cytoplasmic expression (in carcinoma cells) were, respectively, found directly and inversely related with the neoplasm's recurrence rate. CD105 expression was also inversely related with disease-free survival in TBSCC. A future goal of such analyses should be to ascertain the radio- and chemo-sensitivity profiles of individual TBSCCs, enabling truly personalized therapies. A further, more ambitious goal will be to find targets for therapeutic agents that might prove crucial in improving the disease-specific survival for patients with advanced TBSCC.

Deep neck infections originating from the major salivary glands.

OBJECTIVES: Before the widespread use of antibiotics, most deep neck infections (DNIs) stemmed from complicated pharyngeal infections. Nowadays, they seem to be due mainly to dental infections. In 2010, our group reported that DNIs originated from a major salivary gland in 14% of cases. The main endpoint of the present investigation was to review our experience of the diagnosis and treatment of DNIs of salivary gland origin. We also compared the characteristics of DNIs originating from salivary glands with those originating elsewhere. METHODS: Between 2000 and 2011, 44 patients were treated for DNIs of salivary origin at our institution. These patients were compared with 191 cases of DNI diagnosed as having other sites of origin. RESULTS/CONCLUSIONS: In the present series, DNIs originating from a major salivary gland accounted for 19% of all cases of DNI of known origin. Patients with DNI of salivary gland origin were more likely to be elderly than those whose DNI originated from elsewhere (p=0.000). Our multivariate statistical model showed that comorbidities (p=0.051, statistical trend) and the need for surgical treatment (p=0.028) independently predicted long-term hospitalization for DNIs originating from a major salivary gland.

Silver sucrose octasulfate nasal applications and wound healing after endoscopic sinus surgery: a prospective, randomized, double-blind, placebo-controlled study.

OBJECTIVES: The aim of the present prospective, randomized, double-blind, and placebo-controlled investigation (approved by the Ethical Committee of Padova University Hospital [Italy]) was to assess the effect of a nasal gel containing a combination of silver sucrose octasulfate and potassium sucrose octasulfate (Silsos gel® [SG]) in wound healing after endoscopic sinus surgery (ESS) for chronic rhinosinusitis in terms of: nasal symptoms (SNOT22), endoscopic appearance of the sinonasal mucosa (Lund-Kennedy score), nasal air flow (anterior active rhinomanometry), evidence of mucosal inflammatory processes (nasal cytology and histology), and microbiological growth. METHODS: Thirty-four patients with chronic rhinosinusitis were randomized on a 1:1 ratio to receive after ESS either SG or placebo (contained only the excipients [carbopol and propylene glycol] in the same concentrations as in SG). RESULTS/CONCLUSIONS: Judging from the present prospective investigation on patients who underwent ESS for chronic rhinosinusitis, treatment with SG seems to enable a significantly faster improvement in specific symptoms (assessed on the validated SNOT22 scale) than placebo. Patients treated with SG also had a quicker improvement in the endoscopic appearance of their nasal mucosa after ESS than patients treated with placebo. These endoscopic improvements in the SG group were also confirmed at the long-term follow-up, while the same did not apply to the placebo-treated group.

Endoglin (CD105) expression in sinonasal polyposis.

Despite appropriate surgical therapy, 5-10 % of patients with chronic rhinosinusitis (CRS) and nasal polyps (NP) experience disease recurrences. It has been suggested that angiogenesis may relate to the pathogenesis and prognosis of CRS with NP. Endoglin (CD105) is a component of the receptor complex of transforming growth factor-beta, a pleiotropic cytokine that modulates angiogenesis. A series of patients treated surgically for CRS with NP was analyzed to assess the relationship between CD105 expression, main clinicopathological features, and recurrence rate. The immunohistochemical expression of CD105 was assessed in 70 patients consecutively operated for CRS with NP. In the univariate setting, the presence of CD105 (1/0) showed a trend towards a significant association with increasing NP dimensions (p = 0.054). Intensity of CD105 reaction was also significantly associated with NP size (0.04) and with an eosinophilic histology (p = 0.048). In our multivariate setting, only asthma (p = 0.016), hypereosinophilia (p = 0.022), and preoperative polyposis score (p = 0.046) retained their independent prognostic significance in relation to NP recurrence. Further efforts are needed to elucidate the biological, angiogenic and proliferative mechanisms behind recurrent NP. Our preliminary results support the clinical utility of extra postoperative care, in terms of closer follow-ups and medication with oral anti-histamines, topical and/or oral steroids, and antileukotrienes in patients with asthma, advanced nasal polyposis at presentation, and serum hypereosinophilia.

Burkholderia cepacia complex isolation in non-polypoid chronic rhinosinusitis.

PURPOSE: Burkholderia cepacia complex (Bcc) infections of the head and neck have been infrequently reported in immunocompetent patients, while their association with cystic fibrosis is quite well known. One of the main problems associated with Bcc is their intrinsic resistance to most clinically-available antimicrobials. Bcc has already been isolated in sinonasal polyposis, while here we report for the first time on its isolation in patients with chronic rhinosinusitis (CRS) but no nasal polyposis. MATERIALS AND METHODS: Thirty-four consecutive surgically-treated CRS patients without cystic fibrosis were recruited. RESULTS: Bcc was isolated in 4 cases of CRS without polyposis, and in another case in sinonasal polyposis. All tested Bcc strains isolated in non-polypotic CRS were resistant to ciprofloxacin, amikacin, ertapenem, amoxicillin/clavulanate, cefotaxime, and gentamicin. CONCLUSIONS: The novel finding of Bcc species in CRS without polyposis as well suggests that the mechanism by which these bacteria adhere to the epithelium of the upper respiratory tract may be important in the host's colonization.

Multivariate approach to investigating prognostic factors in deep neck infections.

Deep neck infections (DNI) spread along fascial planes and involve neck spaces. Very few studies have investigated potentially prognostic factors using multivariate statistical models. Our aim was to analyze 282 consecutive cases of DNI using multivariate (logistic) statistical models to identify independent significant factors influencing prognosis in terms of complications and long-term hospitalization (>6 days). In our series, only involvement of more than one neck space was independently significant in prognosticating complications of DNI (odds ratio [OR] 2.46). The presence of comorbidities (OR 2.13), non-odontogenic sites of origin (OR 1.88), leukocyte counts above 11.0 cells × 10(9)/L at presentation (OR 3.57), and the need for both medical and surgical treatments (OR 4.66) was significantly and independently prognostic of long hospital stays. Multivariate analysis can distinguish between risk factors and their relative contribution to outcome. The few published studies using multivariate models to analyze DNI prognosis considered quite large cohorts, but no clinical variables persistently revealed an independent significant prognostic role. This evidence seems to underscore the complex interdependence of several clinical variables in contributing to DNI prognosis, and the heterogeneity of the diagnostic/therapeutic approaches adopted.

A prognostic role for Nm23-H1 in laryngeal carcinoma treated with postoperative radiotherapy: an introductory investigation.

Postoperative RT is generally recommended for laryngeal carcinomas (LSCCs) at high risk of recurrence after surgery. There are currently no clinicopathological parameters available to predict response to such adjuvant RT in LSCC, and only a few potentially predictive biomarkers have been investigated. Nm23-H1 protein is reportedly related to the tumor cells' metastatic potential, and low Nm23-H1 expression levels in human carcinomas often correlate with a poor prognosis. The novel aim of the present preliminary study was to investigate the prognostic value of Nm23-H1 expression and subcellular localization in a series of patients given postoperative RT for LSCC. A retrospective clinicopathological investigation was conducted at an academic tertiary referral center of 28 consecutive patients given postoperative RT for LSCC. Image analysis of immunohistochemical reactions was performed to measure Nm23-H1 total and nuclear expression levels. Disease-free survival (DFS) was significantly shorter among LSCC patients with total Nm23-H1 levels <50.0 % (p = 0.03); the mean total Nm23-H1 expression was lower in patients with recurrent disease than in patients without it (statistical trend, p = 0.07). The disease recurrence rate was significantly higher (p = 0.021) and the DFS shorter (statistical trend, p = 0.052) among LSCC patients with nuclear Nm23-H1 levels <5.0 %. The locoregional recurrence-risk ratio in LSCC patients with nuclear Nm23-H1 levels <5.0 % was 9.16. Nm23-H1 warrants further investigation of its potential role as a predictive biomarker with a view to providing tailored treatments after surgery, such as combinations of chemotherapy and RT instead of RT alone, in patients whose LSCCs have low or no Nm23-H1 expression.

Validity and reliability of the Italian translation of the Yale Pharyngeal Residue Severity Rating Scale.

Objective: In the dysphagic patient, pharyngeal residues (PR) are associated with aspiration and poor quality of life. The assessment of PR using validated scales during flexible endoscopic evaluation of swallowing (FEES) is crucial for rehabilitation. This study aims to validate and test the reliability of the Italian version of the Yale Pharyngeal Residue Severity Rating Scale (IT-YPRSRS). The effects of training and experience in FEES on the scale were also determined. Methods: The original YPRSRS was translated into Italian according to standardised guidelines. Thirty FEES images were selected after consensus and proposed to 22 naive raters who were asked to assess the severity of PR in each image. Raters were divided into two subgroups by years of experience at FEES, and randomly by training. Construct validity, inter-rater, and intra-rater reliability were assessed by kappa statistics. Results: IT-YPRSRS showed substantial to almost perfect agreement (kappa > 0.75) in validity and reliability for both the overall sample (660 ratings), and valleculae/pyriform sinus sites (330 ratings each). No significant differences emerged between groups considering years of experience, and variable differences were observed by training. Conclusions: The IT-YPRSRS demonstrated excellent validity and reliability in identifying location and severity of PR.

Nm23-H1 nuclear expression is associated with a more favourable prognosis in laryngeal carcinoma: univariate and multivariate analysis.

AIMS: To use image analysis and multivariate analysis to investigate the prognostic significance of Nm23-H1 subcellular localization in a large cohort of laryngeal squamous cell carcinomas (LSCCs). METHODS AND RESULTS: Nm23-H1 total and nuclear levels were immunohistochemically determined and calculated with an image analysis system in 104 consecutively operated LSCCs. The mean follow-up was 58.3 ± 35.1 months (median 45 months). Total Nm23-H1 levels correlated only with patient stratification by pT (P=0.01). Mean nuclear Nm23-H1 levels were lower in patients with recurrent disease (P=0.01), and disease-free survival (DFS) was longer in patients whose nuclear levels of Nm23-H1 were >2.0% than in those with levels ≤ 2.0% (P=0.019). On multivariate analysis, Nm23-H1 nuclear expression [hazard ratio (HR) 2.59, P=0.005] and N stage (HR 3.60, P=0.0001) were prognostically significant in relation to DFS. CONCLUSIONS: In LSCC, Nm23-H1 nuclear expression may be useful for identifying patients at higher risk of recurrence after treatment and who might be considered for more aggressive therapy. Further investigations are needed before Nm23-H1 can be considered for use in targeted treatments for LSCC.

Pediatric Hearing Loss Management in the COVID-19 Era: Possible Consequences and Resources for the Next Future.

Pediatric hearing loss early diagnosis and treatment have been limited by the current restrictions due to the coronavirus disease 2019 pandemic. The difficulty in accessing the multiple facilities required for the rehabilitative process is influencing the timing of each step of the process. Auditory hearing screening programs, etiological characterization, surgical timing, and speech therapies have all been limited in the past year. The current conditions have forced us to adopt different strategies to overcome the necessary social distancing prescriptions. Although their efficacy should be proved over time, some of these resources will be probably useful even in a nonpandemic future.

Primary temporal bone squamous cell carcinoma: Comparing the prognostic value of the American Joint Committee on Cancer TNM classification (8th edition) with the revised Pittsburgh staging system.

BACKGROUND: Retrospectively considering a temporal bone squamous cell carcinomas (TBSCCs) series, our aim was to compare the predictive power of the American Joint Committee on Cancer (AJCC) staging system (8th edition) with the revised Pittsburgh staging system (rPSS) in terms of disease-free survival (DFS), disease-specific survival (DSS), and overall survival (OS). METHODS: Forty-three TBSCCs consecutively treated surgically were reviewed. The prognostic performance of AJCC and rPSS was compared. RESULTS: The areas under the curves for the prediction of DFS, DSS, and OS did not differ significantly between both staging systems (p = 0.518, p = 0.940, and p = 0.910, respectively). Harrel's C-indexes for respectively the AJCC and rPSS were 0.76 and 0.70 for DFS, 0.73 and 0.76 for DSS, 0.66 and 0.63 for OS. CONCLUSION: Comparable prognostic accuracy was observed between AJCC and rPSS. Levels of prognostic performance were only acceptable for both systems, according to Hosmer-Lemeshow scale. Further efforts are needed to define new TBSCC staging modalities with higher prognostic reliability.

Long-Term Impedance Trend in Cochlear Implant Users with Genetically Determined Congenital Profound Hearing Loss.

BACKGROUND: Impedance is a basic parameter registered at any cochlear implant (CI) fitting section. It is useful in monitoring electrode functioning and the status of the surrounding anatomical structures. PURPOSE: The main aim of this study is to evaluate the 5-year impedance-value trend in patients affected by congenital genetically determined profound hearing loss implanted with Cochlear Nucleus devices. RESEARCH DESIGN: Observational, retrospective, monocentric study. STUDY SAMPLE: Twenty-seven consecutive patients (9 females: 12.0 ± 7.6 years old; range: 4.2-40.4) with genetic diagnosis of GJB2 mutation causing congenital profound hearing loss who underwent cochlear implantation from 2010 to 2020 with good auditory benefit. INTERVENTION: Impedance values of the CIs were obtained from the CIs' programming software that registers those parameters for each follow-up section of each patient. DATA COLLECTION AND ANALYSIS: Impedance values were measured over time (activation, 6, 12, 24, and 60 months after cochlear implantation), for each of the 22 electrodes, in common ground, monopolar 1, monopolar 2, and monopolar 1 + 2 stimulation modes. RESULTS: A significant variation was found between CI activation and 6-month follow-up. This difference was found for each of the 22 electrodes. Electrodes 1 to 4 showed higher impedance values compared with all other electrodes in each time interval. Repeated-measures analysis of variance ruled out significant variations in impedance values from 6-month to 5-year follow-up. CONCLUSIONS: Impedance values were extremely stable after activation, at least for the first 5 years. In these cases, even minimal impedance variations should be carefully evaluated for their possible implications on hearing performance.