Next-generation sequencing improves precision medicine in hearing loss.

Background: An early etiological diagnosis of hearing loss positively impacts children's quality of life including language and cognitive development. Even though hearing loss associates with extremely high genetic and allelic heterogeneity, several studies have proven that Next-Generation Sequencing (NGS)-based gene panel testing significantly reduces the time between onset and diagnosis. Methods: In order to assess the clinical utility of our custom NGS GHELP panel, the prevalence of pathogenic single nucleotide variants, indels or copy number variants was assessed by sequencing 171 nuclear and 8 mitochondrial genes in 155 Spanish individuals with hearing loss. Results: A genetic diagnosis of hearing loss was achieved in 34% (52/155) of the individuals (5 out of 52 were syndromic). Among the diagnosed cases, 87% (45/52) and 12% (6/52) associated with autosomal recessive and dominant inheritance patterns respectively; remarkably, 2% (1/52) associated with mitochondrial inheritance pattern. Although the most frequently mutated genes in this cohort were consistent with those described in the literature (GJB2, OTOF or MYO7A), causative variants in less frequent genes such as TMC1, FGF3 or mitCOX1 were also identified. Moreover, 5% of the diagnosed cases (3/52) were associated with pathogenic copy number variants. Conclusion: The clinical utility of NGS panels that allows identification of different types of pathogenic variants-not only single nucleotide variants/indels in both nuclear and mitochondrial genes but also copy number variants-has been demonstrated to reduce the clinical diagnostic odyssey in hearing loss. Thus, clinical implementation of genomic strategies within the regular clinical practice, and, more significantly, within the newborn screening protocols, is warranted.

Uso de cannabis en médicos de un hospital público de Uruguay / Use of cannabis in physicians of a public hospital of Uruguay

Antecedentes y objetivos. En Uruguay el consumo de cannabis es legal desde 1974, y proporciona un importante contexto permitiendo evaluar prevalencia y actitudes en un régimen legislativo liberal. Los médicos son fuente para el asesoramiento sobre el consumo de cannabis, por lo cual es importante saber en qué medida el consumo personal puede afectar al mismo. Este estudio tuvo como objetivo evaluar la prevalencia de consumo de cannabis en médicos de un hospital. Métodos. Se realizó un estudio transversal con 140 médicos de un hospital público (tasa de respuesta del 100%). El autocuestionario anónimo incluyó: consumo de cannabis, tabaco, ansiedad, depresión formación recibida para abordaje de pacientes, creencias acerca de nocividad y características sociodemográficas. Resultados. Consumieron alguna vez 41,5%, en último año 13,6% y en último mes 2,1%. No hubo consumidores diarios. En una regresión logística multivariable, el uso en el último año se asoció significativamente con el consumo de tabaco (OR ajustada = 4,31; IC de 95% = 1,22 a 15,20) y la edad (OR ajustada = 0,90; IC de 95% = 0,81-0,99); 96,3% informó que creían que el consumo de cannabis es perjudicial para la salud; 41,9% informó haber recibido formación para abordar el consumo de cannabis en pacientes. Conclusiones. El consumo de cannabis ocasional en médicos en Uruguay, un país en el que el uso es legal desde hace más de 40 años, puede ser relativamente común y ligado al consumo de tabaco, a pesar de la aceptación casi universal de que es perjudicial. El uso diario parece ser poco común (AU)

Backgrounds and objectives. In Uruguay cannabis consumption has been legal since 1974, and provides an important context that makes it possible to evaluate prevalence and attitudes in a liberal legislative regime. Physicians are the source for counseling on cannabis consumption, so that it is important to know how much personal consumption may affect it. This study aimed to evaluate prevalence of cannabis consumption in physicians of one hospital. Methods. A cross-sectional study was performed with 140 physicians of a public hospital (response rate: 100%). The anonymous self-questionnaire included: cannabis consumption, smoking, anxiety, depression training received to approach patients, beliefs on harmfulness and sociodemographic characteristics. Results. A total of 41.5% had used cannabis at some time, 13.6% in the last year and 2.1% in the last month. There were no daily consumers. In a multivariable logistic regression, use in the last year was significantly associated with smoking (adjusted OR = 4.31; 95% CI = 1.22 to 15.20) and age (adjusted OR = 0.90; 95% CI = 0.81-0.99); 96.3% reported that they believed cannabis consumption is harmful for health; 41.9% stated they had received training to approach cannabis consumption in patients. Conclusions. Occasional cannabis consumption in physicians in Uruguay, a country where its use has been legal for more than 40 years, may be relatively common and linked to smoking habit, even though there is almost universal acceptance that it is harmful. Daily use seems to be uncommon (AU)

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.

[Guidelines for cochlear implant indication in Navarre]. / Guía clínica para la indicación de implantes cocleares en la Comunidad Foral de Navarra.

Cochlear implants are indicated in severe to profound hearing loss with no benefit with hearing aids. Since the beginning of cochlear implants 30 years ago, auditory outcomes have been improving due to changes introduced in differ-ent areas: electrode design, strategy, surgical technique... Given good results within this period of time, cochlear implant indication has varied too. The aim of this paper is to show an update on indication criteria for cochlear implantation in Navarre, for application in daily practice. The indications are established by consensus amongst the hospitals of the region.

Guía clínica para la indicación de implantes cocleares en la Comunidad Foral de Navarra / Guidelines for cochlear implant indication in Navarre

La colocación de un implante coclear es una medida útil para paliar la hipoacusia neurosensorial de grado severo-profundo en aquellos casos en los que el beneficio del audífono es escaso. Desde su inicio hace 30 años los resultados auditivos han mejorado gracias a los progresivas mejoras que se han adoptado en distintos ámbitos: su diseño, estrategia, técnica quirúrgica... Dados los buenos resultados en este periodo, las indicaciones también han variado. El objetivo de este trabajo es revisar los criterios establecidos y emergentes de indicación de implante coclear, estableciendo de manera consensuada, entre los centros sanitarios de la Comunidad Foral de Navarra, unos criterios actualizados para la indicación del mismo en dicha área territorial, de forma que pueden servir de referencia en situaciones clínicas diferenciadas (AU)

Cochlear implants are indicated in severe to profound hearing loss with no benefit with hearing aids. Since the beginning of cochlear implants 30 years ago, auditory outcomes have been improving due to changes introduced in different areas: electrode design, strategy, surgical technique... Given good results within this period of time, cochlear implant indication has varied too. The aim of this paper is to show an update on indication criteria for cochlear implantation in Navarre, for application in daily practice. The indications are established by consensus amongst the hospitals of the region (AU)

Prevalencia de fumadores internados en un hospital público y mantenimiento del consumo intrahospitalario / Prevalence of smokers admitted to a public hospital and maintenance of in-hospital smoking

Introducción. En Uruguay (prevalencia de tabaquismo 24%) la ley prohíbe fumar en áreas cerradas públicas. Objetivo. Evaluar la prevalencia de fumadores internados, la motivación para el cese y el incumplimiento de la ley de restricción durante la internación. Materiales y métodos. Estudio observacional, analítico. Se entrevistó a pacientes internados en un hospital. Se midió monóxido de carbono espirado (COe). Se incluyeron pacientes mayores de 18 años, capaces de responder y realizar coximetría. Variables: edad, sexo, consumo, fumador intrahospitalario, días de internación, COe, motivación para cese en 6 meses, tratamiento de tabaquismo intrahospitalario. Resultados. n: 99, hombres 62%, edad media 58,7. Fumadores actuales 27,3%, exfumadores 39,4%, no fumadores 33,3%. Entre fumadores actuales: hombres 85%, promedio de internación 18 días, sin tratamiento de tabaquismo 100%, consumo actual 18 cigarrillos día, consumo máximo 30, media de COe 3,5 ppm. Fumadores que fumaron internados 18,5%. Fumadores con intención de cese en 6 meses 74%. Extabaquistas 3/ 39 fumaron internados. Conclusiones. La mayoría de pacientes internados son fumadores o exfumadores. La mayoría de fumadores tienen intención de cese. Continúan fumando y recaen internados un número importante de pacientes incumpliendo las normas. No se realiza tratamiento de cese ni síndrome de abstinencia intrahospitalario. Debemos tratar la adicción y prevenir la abstinencia durante la internación (AU)

Introduction. In Uruguay (prevalence of smoking 24%) law prohibits smoking in enclosed public areas. Objective. Evaluate prevalence of hospitalized smokers, motivation for cessation and fail restriction law during hospitalization. Materials and methods. Observational, analytic study. Interview and mesure of espired carbon monoxide (COe) was made. Inclusion: patients over 18 years old, respond the interview and coximetry perform. Variables: age, sex, consumption, hospitalized smokers, hospitalization, exhaled COe, motivation for quitting next 6 months, treatment of smokers during hospitalization. Results. n: 99, 62% male, mean age 58.7. 27.3 current smokers, 39.4% exsmokers, 33.3% nonsmokers. Among current smokers: male 85%, average hospital stay 18 days, 100% without treatment for smoking addiction. Current consumption 18 cigarettes/day, average of maximum consumption 30 cigarettes/day. Smoked in hospital 18.5%. Smokers with motivation for quitting in next 6 months 74%. Mean COe in nonsmokers and exsmokers: 3.5 ppm. 3/39 exsmokers smoked during hospitalization. Conclusions. Most of the hospitalized patients were smokers or exsmokers. 74% of smokers want to quit. A high number of patients continue smoking or relapse during the hospitalization, and they didn´t enforced restriction rules. No treatment to quit or prevent abstinence syndrome was prescribed. We must treat addiction and abstinence syndrome during hospitalization (AU)

Neurosarcoidosis: Presentación de un caso clínico / Neurosarcoidosis: Presentation of a clinical case

Se presenta el caso clínico de una paciente que ingresa por un cuadro neurológico proteiforme, pero que orientaba a un sufrimiento de tronco cerebral bajo y medular alto. La imagenología confirmó un descenso amigdalino, simulando un Chiari, sin aspecto malformativo, pero que mostró la presencia de lesiones fundamentalmente en la base de cráneo que orientaban a un proceso granulomatoso. La anatomía patológica del material obtenido durante la cirugía confirmó una neurosarcoidosis. La neurosarcoidosis es una enfermedad infrecuente. Forma parte de una de las formas de presentación de la sarcoidosis, afección multisistémica, de carácter inflamatorio, caracterizada por la formación de granulomas. Además de analizarse el caso clínico, se realiza una actualización de la enfermedad y se efectúa una revisión de la escasa bibliografía al respecto.(AU)

Neurosarcoidosis: Presentación de un caso clínico / Neurosarcoidosis: Presentation of a clinical case

Se presenta el caso clínico de una paciente que ingresa por un cuadro neurológico proteiforme, pero que orientaba a un sufrimiento de tronco cerebral bajo y medular alto. La imagenología confirmó un descenso amigdalino, simulando un Chiari, sin aspecto malformativo, pero que mostró la presencia de lesiones fundamentalmente en la base de cráneo que orientaban a un proceso granulomatoso. La anatomía patológica del material obtenido durante la cirugía confirmó una neurosarcoidosis. La neurosarcoidosis es una enfermedad infrecuente. Forma parte de una de las formas de presentación de la sarcoidosis, afección multisistémica, de carácter inflamatorio, caracterizada por la formación de granulomas. Además de analizarse el caso clínico, se realiza una actualización de la enfermedad y se efectúa una revisión de la escasa bibliografía al respecto.

[Determination of normality limit of blood pressure by home self-measurement]. / Determinación del límite de normalidad de la presión arterial mediante la automedida domiciliaria.

OBJECTIVES: Home blood pressure (HBP) is frequently used in clinical evaluation; however the interpretation of the data collected is lacked of a precide definition of normal HBP, so we did this study. METHODS: A random sample of 1,136 was selected, stratified by gender and age (25 up to 64 years old). Those receiving antihypertensive therapy were excluded. Clinical blood pressure (CBP) consisted of three measurements, with the mercury sphygmomanometer (MS) and with the automatic blood pressure device (Omron 705 CP) (AD). Heart rate (HR), body weight and height were registered. HBP: each participant was asked to obtain 9 home measurements, three in the morning (M), three in the afternoon (A) and three at night (N). Statistical methods included Student's t test for paired comparisons, ANOVA and regression analysis. RESULTS: CBP and HBP measurements (mmHg) were obtained in 734 participants. The means of S-CBP/D-CBP with the MS were 123.5 +/- 15.1/ 76.4 +/- 10.4 and 122.4 +/- 14.4/75.6 +/- 10.0 and with the AD, 123.4 +/- 16.1/73.7 +/- 10.4. The average of S-HBP/D-HBP in the total sample was 115.0 +/- 14.3/69.2 +/- 9.0. The HBP measurements were significantly lower than CBP (p < 0.05). The mean of clinic HR was 70.3 +/- 10.4. The average of home HR in the whole sample was 67.9 +/- 9.7. The clinic HR and the home HR were significantly different (p < 0.05). The upper limit of normality for HBP obtained from the values that correspond on the mean +2 SD to the CBP value of 140/90 was 135/82. The 95th percentile value of the HBP in the whole sample was 131/80. The upper limit of normality for HBP obtained from the values that correspond on the regression lines in the group with CBP < 140/90 was 125/78, in the group with CBP >or= 140/90 was 130/81 and in the total sample was 128/81. CONCLUSIONS: We consider that the upper limit of normality of home blood pressure is 130/81. Clinic heart rate is higher than home heart rate, which demonstrates a phenomenon of alerting reaction.

Determinación del límite de normalidad de la presión arterial mediante la automedida domiciliaria / Determination of normality limit of blood pressure by home self-measurement

Objetivos. Dada la gran utilización de este nuevo método diagnóstico que es la AMPA, y la escasa clarificación sobre los valores de normalidad se realizó este estudio. Método. Se seleccionó una muestra de 1.136 personas, de forma aleatoria y estratificada por edad y sexo, de 25 a 64 años. Se excluyeron a los diagnosticados de HTA. En consulta (C) se determinó la PA mediante el esfigmomanómetro de mercurio (Hg) y el aparato automático Omron 705 CP (ap. autom.). Se registró la frecuencia cardíaca (FC), la talla y el peso. En el domicilio (D) se les pidió que obtuviesen 9 mediciones de PA, tres por la mañana (M), tres por la tarde (T) y tres por la noche (N). Se aplicó la «t» de Student de medias pareadas, ANOVA y regresión lineal. Resultados. Las mediciones de PA (mmHg) en C y D se obtuvieron en 734 participantes. Las medias de presión sistólica (PS)/presión diastólica (PD) en C con el esfigmomanómetro Hg fueron 123,5 ± 15,1/76,4 ± 10,4 y 122,4 ± 14,4/75,6 ± 10,0 y con el ap. autom. 123,4 ± 16,1/73,7 ± 10,4. La media de PS/PD en el D de toda la muestra fue 115,0 ± 14,3/69,2 ± 9,0. Al compararla PA de la C y del D existieron diferencias significativas entre las determinaciones en C en relación con las del D (p < 0,05). La media de FC en la C fue 70,3 ± 10,4 (pulsaciones/ minuto). La media de FC en el D de toda la muestra fue 67,9 ± 9,7 siendo superior en C que en el D. Al determinar el límite superior de normalidad en el D mediante la media +2 DE en el grupo seleccionado con una PA en C < 140/90 fue 135/82; mediante el percentil 95 correspondió a 131/80 en el total de la muestra. Al aplicar la regresión a la muestra de participantes con PA < 140/90 se obtuvieron unos valores del límite de normalidad en el D de 125/78; en el grupo de personas seleccionadas con PA ≥ 140/90 fue 130/81 y en la muestra total fue de 128/81

Objectives. Home blood pressure (HBP) is frequently used in clinical evaluation; however the interpretation of the data collected is lacked of a precide definition of normal HBP, so we did this study. Methods. A random sample of 1,136 was selected, stratified by gender and age (25 up to 64 years old). Those receiving antihypertensive therapy were excluded. Clinical blood pressure (CBP) consisted of three measurements, with the mercury sphygmomanometer (MS) and with the automatic blood pressure device (Omron 705 CP) (AD). Heart rate (HR), body weight and height were registered. HBP: each participant was asked to obtain 9 home measurements, three in the morning (M), three in the afternoon (A) and three at night (N). Statistical methods included Student's t test for paired comparisons, ANOVA and regression analysis. Results. CBP and HBP measurements (mmHg) were obtained in 734 participants. The means of S-CBP/D-CBP with the MS were 123.5 ± 15.1/ 76.4 ± 10.4 and 122.4 ± 14.4/75.6 ± 10.0 and with the AD, 123.4 ± 16.1/73.7 ± 10.4. The average of S-HBP/D-HBP in the total sample was 115.0 ± 14.3/69.2 ± 9.0. The HBP measurements were significantly lower than CBP (p < 0.05). The mean of clinic HR was 70.3 ± 10.4. The average of home HR in the whole sample was 67.9 ± 9.7. The clinic HR and the home HR were significantly different (p < 0.05). The upper limit of normality for HBP obtained from the values that correspond on the mean +2 SD to the CBP value of 140/90 was 135/82. The 95th percentile value of the HBP in the whole sample was 131/80. The upper limit of normality for HBP obtained from the values that correspond on the regression lines in the group with CBP < 140/90 was 125/78, in the group with CBP ≥ 140/90 was 130/81 and in the total sample was 128/81. Conclusions. We consider that the upper limit of normality of home blood pressure is 130/81. Clinic heart rate is higher than home heart rate, which demonstrates a phenomenon of alerting reaction

Advantages of binaural hearing provided through bimodal stimulation via a cochlear implant and a conventional hearing aid: a 6-month comparative study.

CONCLUSIONS: Our study data demonstrate the additional benefit derived from continued use of a contralateral hearing aid (HA) post-cochlear implantation for speech recognition ability in quiet and in noise. Postoperative bimodal stimulation is recommended for all subjects who show some speech recognition ability in the contralateral ear as it may offer binaural listening advantages in various listening situations encountered in everyday life. OBJECTIVES: To assess the benefits derived from bimodal stimulation for experienced HA users implanted with a cochlear implant (CI) (score=20% in disyllabic test). The correlation between pre- and postoperative performance on speech perception measures was examined to determine additional criteria for recommending bimodal stimulation postoperatively. MATERIAL AND METHODS: A within-subject repeated-measures design was used, with each subject acting as their own control. Assessments were carried out preoperatively in aided monaural and best-aided conditions and at 6 months postoperatively in CI-alone, contralateral HA-alone and bimodal listening conditions. Speech recognition using Spanish words and sentences materials was assessed at conversational level and for soft speech in quiet. Speech comprehension in noise was assessed using word materials at a signal:noise ratio of +10, for coincident speech in noise and for spatially separated speech in noise. Twelve adult native Spanish subjects with a severe-to-profound hearing impairment who were experienced with optimally fitted conventional amplification and who displayed suboptimal speech understanding preoperatively were enrolled in the study. Preoperatively, conventional amplification was worn by five subjects binaurally and by seven monaurally. RESULTS: Postoperatively, superior speech recognition ability in quiet and in noise for disyllabic words was achieved using bimodal stimulation in comparison to performance for either monaural aided condition. Mean improvement in speech recognition in the bimodal condition was significant over performance in the CI-alone condition for disyllabic words in quiet at 70 (p=0.006) and 55 dB SPL (p=0.028), for disyllabic words in noise at +10 dB with speech and noise spatially separated with the noise source closest to the contralateral HA (S0NHA) (p=0.0005) and when the noise source was closest to the CI ear (S0NCI) (p=0.002). When testing word recognition in noise with speech and noise sources coincident in space, word scores were superior in the bimodal condition relative to the CI-alone condition but this improvement was not significant (p=0.07). The advantages of bimodal stimulation included significant effects of binaural summation in quiet and significant binaural squelch effects in both the S0NHA and S0NCI test conditions. All subjects showed superior performance in the binaural situation postoperatively relative to the best-aided condition preoperatively for one or more test situations.

Audición y lenguaje en niños menores de 2 años tratados con implantación coclear / Hearing and speech in children under 2 years of age with a cochlear implant

Fundamento. Valorar los resultados auditivos y de lenguaje en niños con una sordera congénita tratados mediante implantación coclear antes de los 2 años de edad y analizar las complicaciones surgidas en el proceso de selección, cirugía, programación y seguimiento de estos niños.Material y métodos. Se estudiaron 130 niños de forma prospectiva mediante la comparación de sus resultados individuales repetidos. Los niños se dividieron en dos grupos de edad: menores de 2 años (n=36) y niños entre 2 y 6 años (n=94). La valoración preoperatoria incluyó: 1. Historia, exploración física y ORL. 2. Valoración neuropediátrica, familiar y psicológica. 3. Potenciales auditivos troncoencefálicos. 4. Tomografía computarizada de alta resolución de peñascos. 5. Consejo terapéutico y consentimiento informado. La audición y el lenguaje se valoraron, antes y anualmente después de la cirugía (hasta 5 años), mediante pruebas logoaudiométricas en contexto cerrado y abierto, y con la prueba de Peabody y las escalas de Reynell. Resultados. La audición y el lenguaje mejoraron significativamente en todos los niños, independientemente de su edad. Los resultados, sin embargo, fueron mejores en los niños implantados antes de 2 años. Las pruebas de lenguaje mostraron que el desarrollo del lenguaje en estos niños es comparable al de niños normo-oyentes. La tasa de complicaciones no aumentó en los niños menores de 2 años. Conclusiones. La implantación coclear antes de los 2 años, ofrece unos resultados auditivos y de lenguaje mejores y más rápidos, en comparación con los alcanzados por niños de mayor edad, sin aumento de las complicaciones (AU)

[Hearing and speech in children under 2 years of age with a cochlear implant]. / Audición y lenguaje en niños menores de 2 años tratados con implantación coclear.

BACKGROUND: To compare the auditory abilities and speech performance of children with a profound prelingual bilateral hearing impairment, treated with a cochlear implant (CI) before or after 2 years of age. To analyze the complications arising during the selection process of the children, or as a result of the implantation, programming and follow-up. METHODS: Prospective cohort single-subject repeated-measures study of 130 children who received an implant at our center. The children were divided into two age groups: 0-2 (n=36), and 2-6 years of age (n=94). Preoperative evaluation included: 1. History, physical exploration, and ENT examination. 2. Neuropaediatric examination, family evaluation, and psychological assessment. 3. Auditory brainstem responses. 4. High resolution computed tomogram of temporal bones. 5. Counseling and informed consent. The children were evaluated prior to, and each year following, the intervention (for up to 5 years), using closed and open-set logoaudiometric tests, and speech perception tests. Speech was evaluated according to the Peabody Picture Vocabulary and Reynell general oral expression scale. RESULTS: Auditory and speech perception tests improved significantly in all children after CI, regardless of the follow-up time. The infant's performance was better in the group of early implantees. Speech tests showed that the development of children treated before 2 years of age was similar to that of normal children. No additional complications were observed when compared to CI in older children. CONCLUSIONS: When performed before 2 years of age, CI offers a quicker and better improvement of performance, with no increase in complications when compared with a later intervention.

Cerebral auditory plasticity and cochlear implants.

Previous animal research and clinical experiences in humans suggest the existence of an auditory critical period in language acquisition. We review the literature and present the changes within the cochlear nuclei in bilaterally deafferentated adult non-human primates. We also present and analyse the results of 98 prelingually deaf children and teenagers who underwent a cochlear implantation at the University of Navarra. Patients received a Nucleus 22 or 24 multichannel cochlear implant (CI). They were grouped in five categories according to their age at surgery. Performance is compared with a control group of 58 postlinguals. Only early-implanted prelingual children (before 6 years of age) achieved a complete open-set speech recognition, even with better performance than postlinguals. These results clearly demonstrate the existence of a period of high neural auditory plasticity within the first 6 years of life. The introduction of auditory stimulation with a CI can not restore the loss of neural plasticity out of this period. Prelingual children under 6 years of age should receive a CI as soon as there is a reliable diagnosis of bilateral sensorineural hearing loss.

[Study of surgical complications and technical failures (correction of technical defects) of cochlear implants]. / Estudio de las complicaciones quirúrgicas y los fallos técnicos de los implante cocleares.

INTRODUCTION: Cochlear implants (CI) have proved their clinical efficacy and have overcome a routine treatment for profound sensorineural impairment. In the present paper we review our CI program concerning surgical complications and equipment failures. MATERIAL AND METHODS: One-hundred and thirty-five patients (69 younger and 66 older than 14 years of age) are subjects of the study. They suffered from pre-lingual (86 cases) or post-lingual (49 cases) profound bilateral sensorineural hearing impairment, and all of them received a Mini Nucleus 22 CI in our CI program. We analyze minor and major surgical complications and also CI and external equipment failures. RESULTS: In 6.1% of the patients (8 cases) a surgical complication occurred, 3 of them flap-related complications. In 2 of these cases (1.54%) complications were major. Three patients (2.17%) developed a complete CI failure, while in 8 cases malfunction of one or more electrodes was detected. Cumulative survival of CI was 87 months, without significant differences related to age or gender. Cumulative survival of the processors was 78.6 months, without significant differences related to the type of processor (MSP or Spectra) or gender but related to the age. The microphone failed in 42.2% of the cases. CONCLUSIONS: The CI is a low-morbidity treatment with adequate characteristics of durability and reliability. Nevertheless, some of the external components remain quite vulnerable.

[Auditory brain stem potentials evoked by electrical stimulation of cochlear nuclei during central auditive implant setting]. / Potenciales auditivos troncoencefálicos evocados por la estimulación eléctrica de los núcleos cocleares durante la colocación de implantes auditivos centrales.

INTRODUCTION: The implantation of a stimulator over the surface of the cochlear nuclei can provide a partial auditive capability to patients deaf due to a bilateral lesion of the 8th nerve. Intraoperative monitoring of short latency electrically-evoked potentials is useful to asses the correct positioning of the implant, specially when there are anatomical distortions. PATIENTS AND METHODS: Evoked potentials from two patients with type II neurofibromatosis were recorded during implantation surgery, using a blanker system to eliminate the stimulus artifact. RESULTS: In both cases, two-peak vertex-positive responses were obtained, with latencies between 0.4-0.5 and 1.2-1.4, respectively. This responses are similar to the most frequent response described. DISCUSSION: Intraoperative monitoring of electrically-evoked auditory brainstem responses is a useful technique to confirm the correct positioning of the cochlear stimulator. The study of the morphology of these responses can help to understand the mechanisms involved in the generation by the brainstem of the auditive evoked potentials. More experience on this subject is needed to establish a correlation between intraoperative results and postoperative stimulator function.

Indications and counterindications for cochlear implantation in children.

OBJECTIVE: This study is aimed to analyze the current indications and counterindications of cochlear implantation (CI) in children. STUDY DESIGN: This study reviews the children implanted in our institution looking specifically at the following aspects: 1) auditory criteria for candidate selection; 2) age at implantation; 3) educational environment; and 4) associated handicapping conditions. SETTING: Tertiary referral center with experience in CI since 1989 with inpatient and outpatient care. INTERVENTION: All children received a Mini Nucleus 22 CI device (Cochlear Limited, Australia) in a standard surgical procedure. RESULTS: Regarding auditory criteria, children with average hearing level of 100-105 dB HL are more likely to obtain benefit from a CI than from a hearing aid. The minimum age for CI should be as soon as there is a reliable diagnosis of bilateral profound hearing loss, while the maximum age for CI depends on strict selection criteria of candidates. The educational environment is of a great importance in the rehabilitation process, permitting a progressive change to oral communication. Our experience in CI of children with multiple handicapping conditions is limited to a case of a deaf-blind child who was implanted with a good performance. In the selection of these children it is mandatory to have extensive multidisciplinary evaluation. CONCLUSIONS: An experienced team is needed in the selection of children for CI. Candidates should meet anatomic criteria, have a reliable diagnosis of bilateral profound hearing loss, an evaluation of communication skills, and extensive neuropediatric and socioeducational evaluation.