High-resolution computerized tomography for ossicular replacement prostheses

Introduction To study the accuracy of high-resolution computed tomography (HRCT) for assessing the ossicular structures in cadaveric temporal bone by the distance between temporal bone elements is of great interest. Objectives To record the distances between the malleal neck and both the stapedial head and footplate by HRCT. Further, after partially opening the temporal bone toward the ossicular structure, to record the actual distances between those structures during surgical dissection. Material and methods This study compared actual and HRCT measurements of cadaveric temporal bone. We studied, measured, and recorded distances within and between various structural elements. All data are reported as means and were analyzed to prove the accuracy of HRCT to assess ossicular structure from the temporal bone. Results This study included the temporal bones of 10 male and 10 female cadavers (mean age, 70.4 years). By surgical dissection, the distances between the malleal neck and the stapedial head and footplate were 3.40 and 5.30 mm, respectively (measured from the bone); by HRCT, the corresponding values were 3.35 and 5.29 mm. The intraclass correlation coefficients for assessing ossicular structure in contrast to the actual measurements were 0.901 (malleal neck to stapedial head) and 0.923 (malleal neck to stapedial footplate) (p < 0.05). There were no differences between the actual malleal neck to stapedial head (p = 0.793) or footplate (p = 0.242) measurements. Conclusion HRCT produced statistically comparable, reliable, and accurate measurements compared with actual measurements in cadaveric temporal bone. (AU)

Desarrollo ontogénico de la articulación incudoestapedial / Ontogenic development of the incudostapedial joint

Objetivo: Estudiar el desarrollo de la articulación incudoestapedial en embriones y fetos humanos. Material y método: Se han estudiado 46 huesos temporale scon ejemplares comprendidos entre 9 mm y recién nacidos. Las preparaciones estaban cortadas en serie y teñidas con la técnica de tricrómico de Martins. Resultados: La articulación incudoestapedial adquiere las características de una articulación sinovial de tipo enartrosisa las 16 semanas de desarrollo. El cartílago que recubre las superficies articulares está formado por diferentes estratos que se desarrollan sucesivamente: el superficial, a las 19 semanas; el de transición, entre las 20 y las 23 semanas, y el radial, a partir de las 24 semanas. El hueso subcondral se desarrolla a partir de las 29 semanas por los mecanismos de aposición y extensión del periostal y el endostal, pero no es hasta la semana 34 cuando recubre por completo las superficies articulares, constituidos los fascículos óseos por los que se transmitirán las líneas de fuerza. La cápsula articularse forma a partir de la interzona, la zona superficial desarrolla el ligamento capsular y la interna, la sinovial. Conclusiones: En el momento del nacimiento la articulación incudoestapedial está completamente desarrollada (AU)

Objective: To study the development of the incudostapedial joint in human embryos and foetuses. Material and method: 46 temporal bones with specimens between 9 mm and new-borns were studied. The preparations were sliced serially and dyed using the Martins trichrome technique. Results: The incudostapedial joint takes on the characteristics of a spheroidal joint at 16 weeks of development. The cartilage covering the articular surfaces is formed by different strata that develop in succession: the superficial stratum at 19 weeks, the transitional between 20 and 23 weeks, and the radial from 24 weeks on. The subchondral bone develops after 29 weeks by the mechanisms of apposition and extension of the periosteal and endosteal bones, but it is not until week 34 that it completely covers the articular surfaces, following constitution of the bone fascicles transmitting the lines of force. The articular capsule is formed from the inter-zone, the surface zone develops the capsular ligament, and the internal surface develops the synovial membrane. Conclusions: At the time of birth, the incudostapedial joint is completely developed (AU)

Tratamiento de la patología del complejo incudomaleolar combinada con fijación del estribo mediante maleoestapedotomía / Malleostapedotomy in the pathology of the incudomalleolar complex combined with fixation of the stapes

Introducción: La fijación del estribo combinada con trastornos del complejo incudo-maleolar requiere una reconstrucción de la transmisión del sonido, que, a menudo, resulta difícil de resolver. Esta situación puede presentarse en diversas patologías u observarse en revisiones de estapedectomía. Pacientes y métodos: Presentamos nuestra experiencia de cuatro pacientes en los que hemos realizado una maleoestapedotomía, con eliminación del ligamento anterior y la apófisis anterior del mango del martillo. Resultados: Comentamos los hallazgos observados en cada uno de los casos, previos a la realización de la técnica. En dos casos se consiguió un cierre del umbral diferencial audiométrico, mientras en los otros dos se obtuvo una mejoría auditiva sin cierre completo. Discusión: Exponemos las distintas causas que pueden originar la hipomovilidad del martillo y del yunque. Realizamos una revisión de la literatura sobre los resultados obtenidos mediante esta técnica en revisiones de estapedectomía

Introduction: Stapes fixation combined with disorders of the incudo-malleolar complex disorders requires a sound transmission reconstruction that often is difficult to solve. This circumstance can turn up in several pathologies and also in revision surgery for otosclerosis. Patients and methods: We present our experience with four patients that underwent to malleostapedotomy with removal of the malleus anterior ligament and the malleus anterior apophysis. Results: We discuss the previous findings in each case. Two patients reached a gap closure and the other two patients obtained an auditive gain without complete gap closure. Discussion: We set out the ethiology of malleus and incus hipomobility. We do a bibliographic review on the results of this technique in revision stapedectomy