Cochlear electrode array misplacement into the superior semicircular canal: a case report and literature review / 临床耳鼻咽喉头颈外科杂志

Electrode array misplacement is a rare complication of cochlear implant. This article reports an 11-year-old boy who was mistakenly implanted the cochlear electrode array into the superior semicircular canal during the initial cochlear implant. After the diagnosis was confirmed, he underwent a second cochlear implant and the electrode array were successfully implanted into the cochlea. This article conducted a systematic review of the literature on electrode array misplacement, and the causes of electrode array misplacement were analyzed from different implantation position.

Dehiscencia del canal semicircular superior: análisis de la producción científica / Superior semicircular canal dehiscence: analysis of scientific production

RESUMEN Introducción: La dehiscencia del canal semicircular es una vestibulopatía periférica rara y poco prevalente, que se caracteriza por una falta de cobertura ósea del canal semicircular superior en la zona más próxima a la duramadre de la fosa cerebral media. Objetivo: Conocer el estado actual y la calidad científica de las publicaciones sobre la dehiscencia del canal semicircular superior (DCSS). Material y método: Se ha realizado una búsqueda bibliométrica con posterior revisión, selección y análisis a partir de ítems relacionados con estudios DCSS en la base de datos Pubmed desde el año 1998 hasta 2017. Resultados: Al estudiar el tipo de publicaciones, el 77% eran artículos originales, 12% revisiones, 9% casos clínicos, 2% cartas al director y respuestas al editor. Los artículos han sido publicados en un total de 108 revistas, siendo Otology and Neurotology la que mayor número de manuscritos presenta con un total de 87, seguida de Head and Neck Surgery con 28 y Laryngoscope con 22. Estados Unidos se posiciona como el principal contribuyente a la literatura mundial sobre este tema (42%), seguido de Europa (33%). El idioma de referencia es el inglés con 91% de publicaciones (382). Según el índice de Lotka, la actividad productiva de los autores es de tipo medio/bajo, ya que de los 217 autores que firman en primer lugar, solo 19 tienen más de 10 artículos. Según el índice de impacto Journal Citation Reports, 60% de las publicaciones se localiza en los cuartiles Q1 (116 publicaciones) y Q2 (141 publicaciones), lo que indica que la calidad de los trabajos es alta. La temática ha ido variando con el paso del tiempo, siendo actualmente el diagnóstico con 34,3%, seguido del tratamiento con 25,7%, los temas que más interesan. Aunque se trata principalmente de un tema del campo de la otorrinolaringología, en los últimos años ha despertado interés en otras áreas como la neurología y la radiología. Conclusión: Este estudio revela como los trabajos sobre DCSS presentan un escaso número de autores, las publicaciones se concentran en pocas revistas, pero de una alta calidad, y el estado actual del tema está en fase de crecimiento exponencial.

ABSTRACT Introduction: The dehiscence of the semicircular canal is a rare and not very prevalent peripheral vestibulopathy, characterized by a lack of bony coverage of the superior semicircular canal in the area closest to the dura of the middle cerebral fossa. Aim: To know current status and scientific quality of publications of the superior semicircular canal dehiscence (SSCD). Material and method: Bibliometric research with review, selection and analysis from ítems related with SSCD studies in the Pubmed database from 1998 to 2017. Results: 77% of publications were original articles, 12% reviews, 9% clinical cases, 2% letters and answers to the editor. The articles have been published in 108 journals. The top publishing journal is Otology and Neurotology with 87 publications, followed by Head and Neck Surgery with 28 and Laryngoscope with 22. USA is the main global contributor to the world literature on this subject (42%) followed by Europe (33%). The publication reference language is English, with the 91% of publications (382). According to Lotka's index, the general production activity of the authors is at the middle/low level. According to JCR impact factor, there are 60% of the publications in Q1 (116 articles) and Q2 (141 articles) quartiles, which indicates that the quality is high. The subject of the publications has varied over time, being currently diagnostic with 34.3%, followed by treatment with 25.7%, the subjects that most interest. In recent years it has aroused interest in other areas such as neurology or radiology. Conclusion: The work on DCSS has a small number of authors, the publications are limited to a few journals, but of a high quality, and the current state of the subject is in phase of exponential growth.

Dehiscencia del canal semicircular superior como causa de tinnitus pulsátil / Superior semicircular canal dehiscence as cause of pulsatile tinnitus

RESUMEN El tinnitus se presenta en forma crónica en alrededor del 10% de los adultos, siendo el 4% de estos casos tinnitus pulsátil (TP). El TP se caracteriza por ser rítmico y sincrónico al latido cardiaco. Existen múltiples causas descritas, pero en un grupo importante de casos, no se logra objetivar su origen. Nuestro objetivo es presentar casos de dehiscencia del canal semicircular superior (DCSS) como causa de tinnitus pulsátil y su estudio. Se presentan dos pacientes evaluadas por tinnitus pulsátil. En ambos casos se descartan causas sistémicas, ECO doppler carotídeo sin alteración, angio TAC y RNM sin hallazgos. En reconstrucción de Pöschl se sospecha DCSS, por lo que se estudia con potenciales miogénicos evocados cVEMP y oVEMP con disminución de umbral y respuesta aumentada en oído afectado. En los casos expuestos el tinnitus aparece como síntoma único asociado a la presencia de DCSS, que fue confirmada con estudio imagenológico y VEMPs. El estudio con angio TAC permite pesquisar diversas causas asociadas. Los VEMPs confirman el diagnóstico, teniendo el oVEMP mayor sensibilidad. Como conclusión la DCSS es una entidad a tener presente como diagnóstico diferencial del tinnitus pulsátil y ante su sospecha se debe explorar con VEMPs.

ABSTRACT Tinnitus occurs chronically in about 10% of adults, being pulsatile tinnitus a 4% of these cases (TP). TP is characterized by being rythmic and sychronous to the heart beat. There are many described causes, but in a significant group of cases it is not possible to determine its origin. Our aim is present clinical cases of superior semicircular canal dehiscence (SSCD) as the cause of pulsatile tinnitus and its study. Clinical cases: Two patients present pulsatile tinnitus in her right ear. System causes were discarded, normal Carotid Doppler ultrasonography, Anglo CT scan and MRI without findings. In Pöschl reconstruction SSCD can be observed. Evoked myogenic potentials (VEMPs) by suspicion of SSCD Syndrome, cVEMP and oVEMP with a elevated amplitudes and lower thresholds ipsilateral response. In the cases exposed, tinnitus appears as a single symptom associated with the presence of SSCD which was confirmed with imaging studies and VEMPs. The AngioTAC allows to investigate several associated causes. The VEMPs confirm the diagnosis, with oVEMP having a greater sensitivity. The SSCD is an entity to have in my mind as a differential diagnosis of pulsatile tinnitus and, if suspected, should be explored with VEMPs.

Superior Semicircular Canal Dehiscence Syndrome - Diagnosis and Surgical Management

Abstract Introduction Superior semicircular canal dehiscence syndrome was described by Minor et al in 1998. It is a troublesome syndrome that results in vertigo and oscillopsia induced by loud sounds or changes in the pressure of the external auditory canal or middle ear. Patients may present with autophony, hyperacusis, pulsatile tinnitus and hearing loss. When symptoms are mild, they are usually managed conservatively, but surgical intervention may be needed for patients with debilitating symptoms. Objective The aim of this manuscript is to review the different surgical techniques used to repair the superior semicircular canal dehiscence. Data Sources PubMed and Ovid-SP databases. Data Synthesis The different approaches are described and discussed, as well as their limitations.We also review the advantages and disadvantages of the plugging, capping and resurfacing techniques to repair the dehiscence. Conclusions Each of the surgical approaches has advantages and disadvantages. The middle fossa approach gives a better view of the dehiscence, but comes with a higher morbidity than the transmastoid approach. Endoscopic assistance may be advantageous during the middle cranial fossa approach for better visualization. The plugging and capping techniques are associated with higher success rates than resurfacing, with no added risk of hearing loss.

Síndrome de dehiscencia del canal semicircular superior: a propósito de un caso / Canal dehiscence syndrome of the superior semicircular: in a case purpose

El síndrome de dehiscencia de canal semicircular superior (DCSS) es una patología descrita en 1998 por Minor y cols, presenta síntomas diversos incluido vértigo inducido por el sonido, hipoacusia y autofonía por la falta de cobertura ósea en dicho canal. El diagnóstico se basa en la clínica y la confirmación se obtiene mediante la tomografía computarizada de peñasco. El tratamiento será expectante o reparación quirúrgica de la continuidad si la clínica es incapacitante. En este artículo se presenta un caso clínico de DCSS con síntomas auditivos y vestibulares al emitir el fonema "mmm".

The superior semicircular dehiscence síndrome is a pathology described en 1998 by Minor et al. Which presents several symptoms incluid sound induced vértigo, hearing loss and autophony due to bone dehiscense of this semicircular canal. The diagnosis was based on clinical and confirmation is given by the temporal bone CT. Treatment is expectant or surgical repair of continuity if the clinic is disabling. In this paper we present a case of DCSS with auditory and vestibular symptoms in issuing the phoneme "mmm".

A Case of Superior Semicircular Canal Dehiscence Syndrome with Coexisting Otosclerosis / 대한이비인후과학회지

Superior semicircular canal dehiscence (SSCD) syndrome and otosclerosis have overlapping clinical manifestations that can be difficult to distinguish. Audiovestibular symptoms are caused by noise or straining in SSCD, which is associated with the presence of an air-bone gap that overlaps with the characteristic of otosclerosis. We recently examined a 51-year-old woman presenting with unilateral pulsatile tinnitus and ipsilateral hearing loss in the left ear. Computerized tomography, audiometry and vestibular function test confirmed the diagnosis of ipsilateral SSCD syndrome with coexisting ipsilateral otosclerosis. The patient underwent surgical repair of dehiscence by middle fossa approach and stapes surgery for otosclerosis sequentially. She has not had pulsatile tinnitus postoperatively, and hearing improved with the closure of air-bone gap at most frequencies. In conclusion, when SSCD syndrome and otosclerosis coexist and patient has representative symptoms of both ear pathologies, a sequential surgery can be an effective treatment option.

Peculiaridades anatómicas del canal semicircular superior y su posible implicancia clínica / Anatomical peculiarities of the superior semicircular canals and its possible clinical implication

El objetivo fue estudiar las peculiaridades en la morfología apical del canal semicircular superior, a nivel de la eminencia arcuata con la finalidad de obtener conclusiones aplicativas. Se estudiaron 48 cabezas de cadáveres humanos (96 huesos temporales), con la intención de identificar la presencia de adelgazamiento o dehiscencia del canal semicircular superior, así como la existencia de surcos vasculares de la eminencia acuata que, discurriendo sobre el techo del canal, pudieran afectar a su integridad anatómica. El estudio incluye un análisis histológico (Tricrómico de Martins) y radiológico (Tomografía Computarizada) de los hallazgos positivos (dehiscencias y adelgazamientos), así como estudio tomográfico de los canales con surcos vasculares visibles. En un caso (1,04 por ciento hemos observado cómo el canal presentaba un defecto óseo completo (dehiscencia), en tres (3,12 por ciento) el canal presentaba una pared muy delgada cuyo grosor no excedía de 0,2 mm. En 12 casos (12,5 por ciento) la eminencia arcuata estaba recorrida por surcos por el que discurrían vasos colaterales meníngeos, que determinaron una concavidad entre 0,1 y 0,2 mm, mientras que el grosor medio de dicha pared en estos casos fue de 1,2 mm. De las tres peculiaridades estudiadas, la falta de cobertura ósea es la que produce el síndrome de dehiscencia del canal semicircular superior. Los canales que presentaban una cubierta adelgazada pueden estar predispuestos a una rotura y por lo tanto causar patología en el canal. En cambio la presencia de surcos vasculares que recorren la superficie apical del canal, no parece tener consecuencias al disminuir minimamente su grosor...

The aim was to study the peculiarities in apical morphology of the superior semicircular canal are studied at level of the arcuate eminence to obtain application conclusions. We have studied 48 heads from human cadavers (96 temporal bones), with the intention of identifying the presence of thinning or dehiscence in the superior semicircular canal, as well as the existence of vascular sulci of the arcuate eminence, which, traveling along the roof of the canal, may affect its anatomical integrity. The study includes a histological (Martin's Trichome method) and a radiological analysis (Computerized Tomography) of the findings (dehiscences and thinnings), and as well as tomographic study of the canals with visible vascular sulci. In one case (1.04 percent we have observed how the canal presented a complete bone defect (dehiscence), in three (3.12 percent), presented a very thin wall, which did not exceed 0.2 mm thick. In 12 cases (12.5 percent) sulci covered the arcuate eminence through which meningeal collateral vessels ran, which determined a concavity of between 0.1 and 0.2 mm, whilst the average thickness of this wall in these cases was 1.2 mm. Of the peculiarities studied, the lack of bone coverage is what produces the dehiscence syndrome of the superior semicircular canal. The canals that had a reduced coverage may be predisposed to breakage and therefore cause pathology in them. On the other hand, the presence of vascular sulci that ran along the apical surface of the canal seems to have no consequences to decrease their thickness...

Dehiscencia del canal semicircular superior: estudio de la incidencia anatómica / Dehiscence in the superior semicircular canal: anatomic incidence study

Introducción: La presencia de dehiscencia de canal semicircular superior presenta una notable diferencia entre la incidencia radiológica (del 1 por ciento al 19 por ciento) y la anatómica (entre 0,4 por ciento y 0,6 por ciento). Objetivo: El objetivo del trabajo es determinar la incidencia anatómica de la dehiscencia del canal semicircular superior y compararla con la incidencia radiológica. Material y método: Se estudia la incidencia de dehiscencia de canal semicircular superior en 80 cráneos (160 temporales). Resultados: Hemos observado la presencia de una dehiscencia del canal semicircular superior en un cráneo de los 80 estudiados, lo que representó una incidencia del 0,6 por ciento. Se discute las posibles causas porque la prevalencia de los estudios radiológicos es marcadamente superior a la de los estudios anatómicos. Conclusión: Es evidente que se realiza un "sobrediagnóstico" de dehiscencias del canal semicircular superior ya que los hallazgos anatómicos están muy lejos de los resultados obtenidos con técnicas de imagen.

Introduction: The presence of dehiscence in the superior semicircular canal shows a remarkable difference between radiological (from 1 percent to 19 percent) and anatomical incidence (between 0,4 percent and 0,6 percent) Aim: To determine the incidence anatomical superior semicircular canal dehiscence. Material and method: The incidence of dehiscence in superior semicircular canal in 80 skulls (160 temporal bones) is studied. Results: We have observed the presence of one dehiscence in the superior semicircular canal in one skull from the 80 studied, representing an incidence of 0.6 percent. The possible causes are discussed because of the prevalence of the radiological studies is highly superior to anatomical studies. Conclusion: It is obvious the over-diagnosis performed about the dehiscences in the superior semicircular canal since anatomical finds are quite different from the results obtained by means of image technics.

A Case of Superior Semicircular Canal Dehiscence Syndrome Treated with Surgical Repair / 대한이비인후과학회지

Superior semicircular canal dehiscence syndrome (SCDS) is a rare disease caused by dehiscence in the bone overlying superior semicircular canal. Patients with SCDS present vestibular and auditory manifestations including dizziness and hyperacusis. These manifestations can be controlled by surgical repair of the dehiscence such as plugging or resurfacing the defect. We report a case of a 25 year-old man with SCDS who underwent surgical repair of dehiscence through middle fossa approach.

A Case of Superior Semicircular Canal Dehiscence Syndrome / 대한이비인후과학회지

Dehiscence of bone overlying the superior semicircular canal (superior semicircular canal dehiscence syndrome) may have both vestibular and auditory manifestations. Lowered vestibular evoked myogenic potential (VEMP) threshold in patients with an apparent conductive hearing loss and normal acoustic reflex also suggests this syndrome. Herein, we present a patient with the Tullio phenomenon, sound induced nystagmus, vibration induced nystagmus, and lowered VEMP threshold without conductive hearing loss due to the superior semicircular canal dehiscence.

Clinical Analysis of Down Beat Nystagmus in Atypical Positional/ing Vertigo

BACKGROUND AND OBJECTIVES:Traditionally, down beat nystagmus is regarded as a sign of central nervous system dysfunction. But, several years has passed since Herdman et al reported the down beat nystagmus developed during treatment maneuvers for posterior semicircular canal benign paroxysmal positional vertigo(BPPV). We undertook this study to evaluate the character and clinical analysis of the positional or positioning down beat nystagmus, to discuss the clinical significance of positional or positioning down beat nystagmus as a diagnostic criteria of superior semicircular canal BPPV, and to propose the new treatment method. MATERIALS AND METHOD:From November 1999 to March 2004, we sampled the 103 patients with positional or positioning down beat nystagmus. Of these patients, we selected 16 patients except for the patients with central nervous system dysfunction, nonspecific or artifact result, idiopathic origin. RESULTS:All of 16 patients had no sign and radiologic result of central nervous system disorder. 10 patients was reported or suspected the diagnosis of posterior semicircular canal BPPV. Fatigability was reported in 9 patients and reversibility was reported in 1 patient. Average latency was checked less than 2 seconds. CONCLUSION:Although the diagnostic criteria of superior semicircular canal BPPV that we reported was not controversial, we expect that this criteria is useful in diagnosis for patients with atypical positional or positioning down beat nystagmus. And the new treatment method that we reported will has the better results than previous method.