Improving quality of life in the elderly: hearing loss treatment with cochlear implants.

BACKGROUND: Hearing loss impacts health-related quality of life and general well-being and was identified in a Lancet report as one of the largest potentially modifiable factors for the prevention of age-related dementia. There is a lack of robust data on how cochlear implant treatment in the elderly impacts quality of life. The primary objective was to measure the change in health utility following cochlear implantation in individuals aged ≥ 60 years. METHODS: This study uniquely prospectively recruited a large multinational sample of 100 older adults (mean age 71.7 (SD7.6) range 60-91 years) with severe to profound hearing loss. In a repeated-measures design, pre and post implant outcome measures were analysed using mixed-effect models. Health utility was assessed with the Health Utilities Index Mark III (HUI3). Subjects were divided into groups of 60-64, 65-74 and 75 + years. RESULTS: At 18 months post implant, the mean HUI3 score improved by 0.13 (95%CI: 0.07-0.18 p < 0.001). There was no statistically significant difference in the HUI3 between age groups (F[2,9228] = 0.53, p = 0.59). The De Jong Loneliness scale reduced by an average of 0.61 (95%CI: 0.25-0.97 p < 0.014) and the Lawton Instrumental Activities of Daily Living Scale improved on average (1.25, 95%CI: 0.85-1.65 p < 0.001). Hearing Handicap Inventory for the Elderly Screening reduced by an average of 8.7 (95%CI: 6.7-10.8, p < 0.001) from a significant to mild-moderate hearing handicap. Age was not a statistically significant factor for any of the other measures (p > 0.20). At baseline 90% of participants had no or mild depression and there was no change in mean depression scores after implant. Categories of Auditory perception scale showed that all subjects achieved a level of speech sound discrimination without lip reading post implantation (level 4) and at least 50% could use the telephone with a known speaker. CONCLUSIONS: Better hearing improved individuals' quality of life, ability to communicate verbally and their ability to function independently. They felt less lonely and less handicapped by their hearing loss. Benefits were independent of age group. Cochlear implants should be considered as a routine treatment option for those over 60 years with bilateral severe to profound hearing loss. TRIAL REGISTRATION: ClinicalTrials.gov ( http://www. CLINICALTRIALS: gov/ ), 7 March 2017, NCT03072862.

Normocephalic sagittal craniosynostosis in young children is common and unrecognized.

OBJECTIVE: Sagittal craniosynostosis (SC) is usually diagnosed during early childhood by the presence of scaphocephaly. Recently, our group found 3.3% of children under 5 years of age with normocephalic sagittal craniosynostosis (NSC) using computed tomography (CT) scans. This paper aims to validate our preliminary findings using a larger cohort of patients, and analyze factors associated with incidental NSC. METHODS: A retrospective review of head CT scans in patients aged 0 to 71 months who presented to the emergency department of our tertiary care institution between 2008 and 2020 was completed. Patients with syndromes associated with craniosynostosis (CS), history of hydrocephalus, or other brain/cranial abnormalities were excluded. Two craniofacial surgeons reviewed the CT scans to evaluate the presence and extent of CS. Demographic information, gestational age, past medical and family history, medications, and chief complaint were recorded as covariates, and differences between patients with and without CS were analyzed. Furthermore, comparison of the prevalence of CS across age groups was studied. Additional analysis exploring association between independent covariates and the presence of CS was performed in two sub-cohorts: patients ≤ 24 months of age and patients > 24 months of age. RESULTS: A total of 870 scans were reviewed. SC was observed in 41 patients (4.71% - 25 complete, 16 incomplete), all with a normal cranial index (width/length > 0.7). The prevalence of SC increased up to 36 months of age, then plateaued through 72 months of age. Patients under 2 years of age with family history of neurodevelopmental disease had 49.32 (95% CI [4.28, 567.2]) times higher odds of developing CS. Sub-cohort of patients above 24 months of age showed no variable independently predicted developing CS. CONCLUSION: NSC in young children is common. While the impact of this condition is unknown, the correlation with family history of neurodevelopmental disease is concerning.

Differential involvement of synovial adipokines in pain and physical function in female patients with knee osteoarthritis. A cross-sectional study.

OBJECTIVE: Adipokines have been reported to play a role in the development, progression and severity of knee osteoarthritis but the influence of the different adipokines are not well known. The aim of this study was to evaluate the association between different synovial fluid adipokines with pain and disability knee osteoarthritis patients. METHODS: Cross-sectional study with systematic inclusion of 115 symptomatic primary knee osteoarthritis female patients with ultrasound-confirmed joint effusion. Age, physical exercise, symptoms duration and different anthropometric measurements were collected. Radiographic severity was evaluated according to Kellgren-Lawrence scale. Pain and disability were assessed by WOMAC-total, -pain, -function subscales and Knee injury and Osteoarthritis Outcome Score (KOOS) pain and function scales. Seven adipokines and three inflammatory markers were measured by ELISA in synovial fluid. Partial Correlation Coefficient (PCC) and corresponding 95% confidence interval were used as a measure of association. RESULTS: Leptin, osteopontin and inflammatory factors, especially TNF-alpha, were associated to pain and function. After adjustment for potential confounders including inflammatory factors and all adipokines, an association was found for adiponectin with pain (PCC 0.240 [0.012, 0.444]) and for resistin and visfatin with function (PCC 0.336 [0.117, 0.524] and -0.262 [-0.463, -0.036]). No other adipokines or inflammatory markers were statistically and independently associated. An association between physical exercise and pain and disability remained after adjustment, whereas an attenuation of the influence of anthropometric measurements was observed. CONCLUSIONS: Different patterns of association between synovial fluid adipokines were observed regarding pain and disability in knee osteoarthritis patients. Specifically, adiponectin was associated to pain while resistin and visfatin were mainly related to function.

[Heart failure in primary care: Attitudes, knowledge and self-care]. / Insuficiencia cardiaca en atención primaria: actitudes, conocimientos y autocuidado.

OBJECTIVE: To determine the attitudes, knowledge, and self-care practices in patients with heart failure (HF) in Primary Care, as well as to identify factors associated with better self-care. DESIGN: Cross-sectional and multicentre study. SETTING: Primary Care. PARTICIPANTS: Subjects over 18 years old with HF diagnosis, attended in 10 Primary Health Care Centres in the Metropolitan Area of Barcelona. MAIN MEASUREMENTS: Self-care was measured using the European Heart Failure Self-Care Behaviour Scale. Sociodemographic and clinical characteristics, tests on attitudes (Self-efficacy Managing Chronic Disease Scale), knowledge (Patient Knowledge Questionnaire), level of autonomy (Barthel), and anxiety and depression screening (Goldberg Test), were also gathered in an interview. A multivariate mixed model stratified by centre was used to analyse the adjusted association of covariates with self-care. RESULTS: A total of 295 subjects (77.6%) agreed to participate, with a mean age of 75.6 years (SD: 11), 56.6% women, and 62% with no primary education. The mean self-care score was 28.65 (SD: 8.22), with 25% of patients scoring lower than 21 points. In the final stratified multivariate model (n=282; R2 conditional=0.3382), better self-care was associated with higher knowledge (coefficient, 95% confidence interval: -1.37; -1.85 to -0.90), and coronary heart disease diagnosis (-2.41; -4.36: -0.46). CONCLUSION: Self-care was moderate. The correlation of better self-care with higher knowledge highlights the opportunity to implement strategies to improve self-care, which should consider the characteristics of heart failure patients attended in Primary Care.

High prevalence of cardiovascular co-morbidities in patients with symptomatic knee or hand osteoarthritis.

OBJECTIVES: To evaluate the frequency of cardiovascular events (CVEs) and metabolic syndrome (MetS) in patients with symptomatic knee or hand osteoarthritis (OA). METHOD: A cross-sectional study conducted by rheumatologists in a primary care setting. Consecutive symptomatic patients with primary knee or hand OA were included and patients with soft tissue conditions served as the control group. Hypertension, diabetes mellitus, obesity, dyslipidaemia, and CVEs consisting of myocardial infarction, angina, or cerebrovascular disease were recorded. RESULTS: A total of 254 OA patients (184 with knee OA and 70 with hand OA) and 254 control patients were included. The frequency of obesity was higher in all OA groups and hypertension was more frequent in knee OA. MetS was significantly more frequent in patients with OA as a whole group and in knee or hand OA groups separately (p < 0.001, p = 0.002, and p = 0.007, respectively, vs. control group), with odds ratio (OR) 2.4, 95% confidence interval (CI) 1.26-4.55 in the OA group, OR 2.29, 95% CI 1.15-4.54 in the knee OA group, and OR 2.67, 95% CI 1.15-6.19 in the hand OA group. A higher prevalence of CVEs in the three OA groups was observed compared with the control group. CONCLUSIONS: A high frequency of MetS and CVEs was observed in OA patients in a primary care setting.

Surgical findings and auditory performance after cochlear implant revision surgery.

The objective of this study was to review cochlear reimplantation outcomes in the tertiary hospital and analyze whether facts such as type of failure, surgical findings, or etiology of deafness have an influence. A retrospective study including 38 patients who underwent cochlear implant revision surgery in a tertiary center is performed. Auditory outcomes (pure tone audiometry, % disyllabic words) along with etiology of deafness, type of complication, issues with insertion, and cochlear findings are included. Complication rate is 2.7 %. Technical failure rate is 57.9 % (50 % hard failure and 50 % soft failure), and medical failure (device infection or extrusion, migration, wound, or flap complication) is seen in 42.1 % of the cases. Management of cochlear implant complications and revision surgery is increasing due to a growing number of implantees. Cases that require explantation and reimplantation of the cochlear implant are safe procedures, where the depth of insertion and speech perception results are equal or higher in most cases. Nevertheless, there must be an increasing effort on using minimally traumatic electrode arrays and surgical techniques to improve currently obtained results.

[p53 expression in the gastric mucosa of patients infected with Helicobacter pylori]. / p53 expresado en la mucosa gástrica de pacientes infectados por Helicobacter pylori.

BACKGROUND: Helicobacter pylori (Hp) is recognized as a type 1 carcinogen for gastric cancer associated with pre-neoplastic lesions (atrophy and intestinal metaplasia [IM]). Its relation with p53, which intervenes in the cell cycle, has had contradictory results. AIMS: To analyze p53 expression in gastric mucosa and its relation with Hp infection. METHODS: A 3-month prospective, observational, cross-sectional study was conducted. Patients that had no evidence of acute or clinically significant gastric pathology had biopsies taken according to the Sydney system at the Hospital Juárez de México and the histopathologic studies were done at the Hospital Español de México. RESULTS: Hp prevalence was 32.7% in 104 patients. There were no cases of atrophy or dysplasia. A total of 91% of the infected patients were positive for p53. Of the non-infected patients, 14% were positive for p53 and 60% of them had IM. Of the IM patients, 75% presented with positive p53. Of the patients without IM, 31 presented with positive p53, and Hp was positive in 85% of them. There was association between Hp and p53 and between p53 and IM (P<.0001 and P<.0006, respectively). CONCLUSIONS: Significant association was shown between Hp and p53 expression, even in patients with pre-neoplastic lesions that no longer presented with Hp. Given that the identification of pre-neoplastic lesions is important for the prevention of cancer, immunohistochemistry could benefit routine biopsy carried out during endoscopy for the detection of Hp, by identifying patients with expression of the important oncogene regulator, p53.

[Mexican consensus on portal hypertension]. / Consenso Mexicano de Hipertensión Portal.

The aim of the Mexican Consensus on Portal Hypertension was to develop documented guidelines to facilitate clinical practice when dealing with key events of the patient presenting with portal hypertension and variceal bleeding. The panel of experts was made up of Mexican gastroenterologists, hepatologists, and endoscopists, all distinguished professionals. The document analyzes themes of interest in the following modules: preprimary and primary prophylaxis, acute variceal hemorrhage, and secondary prophylaxis. The management of variceal bleeding has improved considerably in recent years. Current information indicates that the general management of the cirrhotic patient presenting with variceal bleeding should be carried out by a multidisciplinary team, with such an approach playing a major role in the final outcome. The combination of drug and endoscopic therapies is recommended for initial management; vasoactive drugs should be started as soon as variceal bleeding is suspected and maintained for 5 days. After the patient is stabilized, urgent diagnostic endoscopy should be carried out by a qualified endoscopist, who then performs the corresponding endoscopic variceal treatment. Antibiotic prophylaxis should be regarded as an integral part of treatment, started upon hospital admittance and continued for 5 days. If there is treatment failure, rescue therapies should be carried out immediately, taking into account that interventional radiology therapies are very effective in controlling refractory variceal bleeding. These guidelines have been developed for the purpose of achieving greater clinical efficacy and are based on the best evidence of portal hypertension that is presently available.

Eye oscilations with neurological implications in pediatric age.

INTRODUCTION: Eye oscillations, both nystagmic and non-nystagic, can occur from birth. Most correspond to infantile nystagmus that dubates in the first six months of life, which include idiopathic, sensory, latent, or overt latent motor nystagmus. Those associated with neurological diseases or syndromes correspond to approximately 33%, their identification and correct evaluation being important given the potential visual and vital complications. MATERIAL AND METHODS: We made a systematic review of the literature on supranuclear gaze control mechanisms and the main ocular oscillations with possible neurological implications, both in childhood. With this, we intend to assess if there are already established clinical-anatomical associations, and to propose a protocol on the complementary studies to be carried out in these cases. RESULTS: There are still anatomical pathways involved in supranuclear gaze control that are not fully clarified and understood. Besides, except in the case of nystagmus in seesaw and upbeat, we did not find anatomical explanations for their pathogenesis. The need for complete neuro-ophthalmological physical examinations and the request for additional tests in children who present ocular oscillations with neurological characteristics are clear. CONCLUSIONS: Supranuclear gaze control follows a complex neurological network that still needs to be studied better. With a better dissection of the same we could try to understand why the ocular oscillations that we studied have these specific forms of presentation. As for the complementary requests, the request for neuroimaging tests is practically constant, making the others according to the specific case before which we find ourselves.

Inner ear drug delivery through a cochlear implant: Pharmacokinetics in a Macaque experimental model.

OBJECTIVES: The method of drug delivery directly into the cochlea with an implantable pump connected to a CI electrode array ensures long-term delivery and effective dose control, and also provides the possibility to use different drugs. The objective is to develop a model of inner ear pharmacokinetics of an implanted cochlea, with the delivery of FITC-Dextran, in the non-human primate model. DESIGN: A preclinical cochlear electrode array (CI Electrode Array HL14DD, manufactured by Cochlear Ltd.) attached to an implantable peristaltic pump filled with FITC-Dextran was implanted unilaterally in a total of 15 Macaca fascicularis (Mf). Three groups were created (5 Mf in each group), according to three different drug delivery times: 2 hours, 24 hours and 7 days. Perilymph (10 samples, 1µL each) was sampled from the apex of the cochlea and measured immediately after extraction with a spectrofluorometer. After scarifying the specimens, x-Rays and histological analysis were performed. RESULTS: Surgery, sampling and histological analysis were performed successfully in all specimens. FITC-Dextran quantification showed different patterns, depending on the delivery group. In the 2 hours injection experiment, an increase in FITC-Dextran concentrations over the sample collection time was seen, reaching maximum concentration peaks (420-964µM) between samples 5 and 7, decreasing in successive samples, without returning to baseline. The 24-hours and 7-days injection experiments showed even behaviour throughout the 10 samples obtained, reaching a plateau with mean concentrations ranging from 2144 to 2564 µM and from 1409 to 2502µM, respectively. Statistically significant differences between the 2 hours and 24 hours groups (p = 0.001) and between the 2 hours and 7 days groups (p = 0.037) were observed, while between the 24 hours and 7 days groups no statistical differences were found. CONCLUSIONS: This experimental study shows that a model of drug delivery and pharmacokinetics using an active pump connected to an electrode array is feasible in Mf. An infusion time ranging from 2 to 24 hours is required to reach a maximum concentration peak at the apex. It establishes then an even concentration profile from base to apex that is maintained throughout the infusion time in Mf. Flow mechanisms during injection and during sampling that may explain such findings may involve cochlear aqueduct flow as well as the possible existence of substance exchange from scala tympani to extracellular spaces, such as the modiolar space or the endolymphatic sinus, acting as a substance reservoir to maintain a relatively flat concentration profile from base to apex during sampling. Leveraging the learnings achieved by experimentation in rodent models, we can move to experiment in non-human primate with the aim of achieving a useful model that provides transferrable data to human pharmacokinetics. Thus, it may broaden clinical and therapeutic approaches to inner ear diseases.

[Thoracoscopic sympathectomy: a literature review]. / Simpatectomía toracoscópica: una revisión de la literatura.

INTRODUCTION: Since its first description by Kux in 1954, the thoracic endoscopic (thoracoscopic) sympathectomy has rendered the open techniques obsolete in the treatment of the hyperhidrosis and other sympathetic-related diseases. AIM. The goal of this article is to present a critical review of the current indications, results and complications of the endoscopic thoracic sympathectomy. MATERIAL AND METHODS: An extensive search and review of published papers on the thoracoscopic sympathectomy was undertaken. RESULTS: The thoracoscopic sympathectomy has evolved as a therapeutic choice in patients with focal hyperhidrosis, pain syndromes and peripheral vascular disorders, particularly. The results, recurrences and complications are similar to the previously established open procedures; nevertheless, the morbidity, the hospital stay and the time to return to activities of daily living are substantially reduced. The highest success and satisfaction rates (over 95%) were observed among patients treated for focal hyperhidrosis. CONCLUSIONS: The success and complication rates of thoracoscopic sympathectomy are comparable to those of open techniques, with an easier postoperative period and an earlier return to labor and daily living.

Maintenance treatment in metastatic colorectal cancer: in search of the best strategy.

Over the last 2 decades, the standard fluoropyrimidine-based chemotherapy backbone for metastatic colorectal cancer has been complemented by the addition of novel biological agents, achieving impressive increases in 5-year survival rates. Nonetheless, these new combinations have also entailed increases in toxicity, leading to evaluation of de-escalated chemotherapy regimens and "drug holiday" periods in attempts to reduce side effects and optimise quality of life without impairing efficacy. Here, we review the current and emerging evidence for maintenance schedules with chemotherapy and targeted agents, versus continuous treatment after induction treatment, in metastatic colorectal cancer patients.

[Critical review of the subthalamic stimulation in Parkinson's disease]. / Revisión crítica de la estimulación subtalámica en la enfermedad de Parkinson.

The authors critically review subthalamic nucleus (STN) stimulation for Parkinson's disease (PD) at long follow-up (3-5 years). Subthalamic stimulation induce a significant improvement during the "off" medication in the assessment motor score UPDRS (Unified Parkinson Disease Rating Scale) 3-5 years after surgery. Results show that the benefits obtained in tremor, rigidity, bradykinesia, dyskinesias induced by medication and levodopa reduction are significantly maintained during long term. The improvement in other clinical signs as gait and postural stability at long follow-up are not maintained comparing with the benefits obtained one year after surgery. A high percentage of patients show a cognitive disturbance during the follow-up period that may be correlated with the disease progression. The conclusion is that bilateral STN stimulation is an effective treatment for PD patients at long term but it should be considered earlier in the course of PD.

[Psychiatric symptoms in a child with gluten sensitivity]. / Psychische klachten bij kind met glutensensitiviteit.

BACKGROUND: Non-celiac gluten sensitivity (NCGS) is a diagnosis that is increasingly being reported. Psychiatric symptoms can be a rare but serious manifestation of this new clinical entity. CASE REPORT: A 13-year-old girl consulted the paediatrician with abdominal pain, diarrhoea, bloating, and compulsive thoughts and fears; these disappeared on a gluten-free diet. Celiac disease and wheat allergy were excluded. Double-blind placebo-controlled gluten challenge confirmed the diagnosis NCGS. CONCLUSION: Consider a diagnosis of NCGS in patients with psychiatric symptoms in combination with abdominal symptoms.

Modification of the number and phenotype of striatal dopaminergic cells by carotid body graft.

In non-human primates, striatal tyrosine hydroxylase-immunoreactive (TH-ir) cells are increased in number after dopamine depletion and in response to trophic factor delivery. As carotid body cells contain the dopaminotrophic glial cell line-derived neurotrophic factor (GDNF), we evaluated the number, morphology and neurochemistry of these TH-ir cells, in the anterior and posterior striatum of five monkeys treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) which received a graft of carotid body cell aggregates (CBCA) (n = 3) or sham surgery (n = 2), and six MPTP-monkeys that were sacrificed 6 months and 3 years after the last MPTP dose [MPTP I (n = 3) and MPTP II (n = 3), respectively]. Three intact monkeys served as controls. A disability rating scale was used for the assessment of parkinsonism in all lesioned animals, both before and after surgery. For the neurochemical examination, tissue sections were double-labelled with antibodies to TH, dopamine transporter, dopa decarboxylase-67, vesicular monoamine transporter 2, glutamic acid decarboxylase -67, calbindin, parvalbumin, calretinin, neuronal nitric oxide synthase and GDNF. Only animals receiving CBCA graft showed a moderate but significant recovery of parkinsonism that persisted 12 months after the graft. The grafted striatum contained the greatest TH-ir cell density (120.4 +/- 10.3 cells/100 mm2), while the control striatum displayed the lowest (15.4 +/- 6.8 cells/100 mm2), and MPTP I, MPTP II and sham-operated monkeys showed a similar intermediate value (66.1 +/- 6.2, 58.3 +/- 17.2 and 57.7 +/- 7.0 cells/100 mm2, respectively). In addition, in the post-commissural striatum, only CBCA graft induced a significant increase in the TH-ir cell density compared to control animals (47.9 +/- 15.9 and 7.9 +/- 3.2, respectively). Phenotypically, TH-ir cells were striatal dopaminergic interneurons. However, in the grafted animals, the phenotype was different from that in control, MPTP and sham-operated monkeys, with the appearance of TH/GDNF-ir cells and the emergence of two TH-ir subpopulations of different size as the two main differentiating features. Our data confirm and extend previous studies demonstrating that striatal CBCA grafts produce a long-lasting motor recovery of MPTP-monkeys along with an increase in the number and phenotype changes of the striatal TH-ir interneurons, probably by the action of the trophic factors contained in carotid body cells. The increased number of striatal TH-ir cells observed in the grafted striatum may contribute to the improvement of parkinsonism observed after the graft.

[Surgical treatment of Duane's syndrome type I by recession of the medial rectus of the affected eye and faden operation of the contralateral medial rectus]. / Tratamiento quirúrgico del síndrome de Duane, tipo I mediante retroinserción del recto medial del lado afecto y faden del recto medial contralateral.

PURPOSE: Different surgical approaches have been described for the treatment of Duane's syndrome. The purpose of our study is to report the results of patients undergoing recession of the medial rectus (MR) muscle of the affected eye and placement of contralateral MR faden posterior fixation sutures. METHODS: Retrospective study of 11 patients treated by a 4-7 mm recession of the MR of the affected eye and 13 mm faden posterior fixation suture of the contralateral MR in order to correct abnormal head position and esotropia in primary position. RESULTS: After surgery, there was no torticolis in 81.8% of patients, with less than 10 degrees of torticolis in the remainder. In all patients, postoperative esotropia was less than 5 prismatic dioptres. CONCLUSION: This is a safe and effective procedure in Duane's syndrome type I to treat moderate esotropia and torticolis.

Slow oscillatory activity and levodopa-induced dyskinesias in Parkinson's disease.

The pathophysiology of levodopa-induced dyskinesias (LID) in Parkinson's disease is not well understood. We have recorded local field potentials (LFP) from macroelectrodes implanted in the subthalamic nucleus (STN) of 14 patients with Parkinson's disease following surgical treatment with deep brain stimulation. Patients were studied in the 'Off' medication state and in the 'On' motor state after administration of levodopa-carbidopa (po) or apomorphine (sc) that elicited dyskinesias in 11 patients. The logarithm of the power spectrum of the LFP in selected frequency bands (4-10, 11-30 and 60-80 Hz) was compared between the 'Off' and 'On' medication states. A peak in the 11-30 Hz band was recorded in the 'Off' medication state and reduced by 45.2% (P < 0.001) in the 'On' state. The 'On' was also associated with an increment of 77. 6% (P < 0.001) in the 4-10 Hz band in all patients who showed dyskinesias and of 17.8% (P < 0.001) in the 60-80 Hz band in the majority of patients. When dyskinesias were only present in one limb (n = 2), the 4-10 Hz peak was only recorded in the contralateral STN. These findings suggest that the 4-10 Hz oscillation is associated with the expression of LID in Parkinson's disease.

Auditory brainstem implants: past, present and future prospects.

The purpose of the auditory brainstem implant (ABI) is to directly stimulate the cochlear nucleus complex and offer restoration of hearing in patients suffering from profound retrocochlear sensorineural hearing loss. Electrical stimulation of the auditory pathway via an ABI has been proven to be a safe and effective procedure. The function of current ABIs is similar to that of cochlear implants in terms of device hardware with the exception of the electrode array and the sound-signal processing mechanism. The main limitation of ABI is that electrical stimulation is performed on the surface of the cochlear nuclei, thereby making impractical the selective activation of deeper layers by corresponding optimal frequencies. In this article, we review the anatomical, and experimental basis of ABIs and the indications, and surgical technique for their implantation. To the best of our knowledge, we describe the first pathology images of the cochlear nucleus in a patient who had received an ABI.