ABSTRACT
Abstract The developmental investigation of sound transmitting apparatus is important in understanding the ontogenetic processes behind morphological diversity. The development of sound conducting apparatus was studied in Montpellier snake; Malpolon monspessulanus at 6.5, 7.2, 8.3 and 9.3 cm total body lengths using light microscopy study. The columella auris firstly appeared as undifferentiated rod shape mesenchymal cells. As the growth proceeded, it chondrified and differentiates into two main parts. In addition, the viscerocranium components which participate in formation of sound transmitting apparatus undergo critical organization. In more advanced stages, procartilagenous stylohyal chondrified and fuse with the well organized quadrate. These data considered as a base for functional and molecular mechanisms of sound transmitting apparatus studies and identification of diseases that may infect them.
Resumo A investigação do desenvolvimento de equipamentos de transmissão de som é importante na compreensão dos processos ontogenéticos atrás diversidade morfológica. O desenvolvimento de aparelhos de som realização foi estudada em Montpellier cobra; Monspessulanus Malpolon em 6.5, 7.2, 8.3 e 9.3 cm corporal total utilizando comprimentos de estudo de microscopia de luz. O auris columelar em primeiro lugar apareceu como células mesenquimais forma haste indiferenciada. Como o crescimento passou, ele chondrified e diferencia em duas partes principais. Além disso, os componentes viscerocrânio que participam na formação do aparelho de transmissão de som submeter a organização crítico. Em estágios mais avançados, stylohyal procartilagenous chondrified e se fundem com o quadrado bem organizado. Estes dados considerados como uma base para os mecanismos funcionais e estudos moleculares do aparelho de transmissão de som e identificação de doenças que podem infectar-los.
Subject(s)
Animals , Snakes/embryology , Ear/embryology , Hearing/physiologyABSTRACT
Abstract The developmental investigation of sound transmitting apparatus is important in understanding the ontogenetic processes behind morphological diversity. The development of sound conducting apparatus was studied in Montpellier snake; Malpolon monspessulanus at 6.5, 7.2, 8.3 and 9.3 cm total body lengths using light microscopy study. The columella auris firstly appeared as undifferentiated rod shape mesenchymal cells. As the growth proceeded, it chondrified and differentiates into two main parts. In addition, the viscerocranium components which participate in formation of sound transmitting apparatus undergo critical organization. In more advanced stages, procartilagenous stylohyal chondrified and fuse with the well organized quadrate. These data considered as a base for functional and molecular mechanisms of sound transmitting apparatus studies and identification of diseases that may infect them.
Resumo A investigação do desenvolvimento de equipamentos de transmissão de som é importante na compreensão dos processos ontogenéticos atrás diversidade morfológica. O desenvolvimento de aparelhos de som realização foi estudada em Montpellier cobra; Monspessulanus Malpolon em 6.5, 7.2, 8.3 e 9.3 cm corporal total utilizando comprimentos de estudo de microscopia de luz. O auris columelar em primeiro lugar apareceu como células mesenquimais forma haste indiferenciada. Como o crescimento passou, ele chondrified e diferencia em duas partes principais. Além disso, os componentes viscerocrânio que participam na formação do aparelho de transmissão de som submeter a organização crítico. Em estágios mais avançados, stylohyal procartilagenous chondrified e se fundem com o quadrado bem organizado. Estes dados considerados como uma base para os mecanismos funcionais e estudos moleculares do aparelho de transmissão de som e identificação de doenças que podem infectar-los.
ABSTRACT
This study reports tympanic cavity (TC) volume in newborns, which was missing in the literature. Ex vivo histology and computerized tomography (CT) scans were performed on temporal bone and data were analyzed in part using software developed in house. CT images with a slice thickness of 0.5 mm were obtained from 5 newborn cadavers and analyzed independently by two expert researchers. The border of the TC was delineated manually and measurement of area of interest was calculated on masked images. Then, the area measurements from all sections were added to estimate the total volume. The agreements between the histological and CT findings were then compared for accuracy, repeatability and reliability. The Dice and Jaccard similarity coefficient measures were used as a statistical validation metric to evaluate the assessor's performance in manual volume segmentation. Good assessor agreement was observed with average Dice values above 0.8 indicating that consistent and reliable volume measurements were feasible. The proposed protocol was shown to be accurate in calculating the TC volume, and thus can be used for computer-assisted presurgical planning or for diagnosing structural alterations in TC.
El objetivo fue determinar el volumen de la cavidad timpánica (CT) en recién nacidos, información no encontrada en la literatura. Se realizaron escaners a través de tomografia computadorizada (TC) y estudios histológicos en el hueso temporal; los datos se analizaron utilizando un software desarrollado en nuestra institución. Se obtuvieron imágenes de secciones de TC, de 0,5 mm de grosor, a partir de 5 cadáveres de recién nacidos, los que fueron analizados de forma independiente por dos investigadores expertos. El margen de los cortes de TC fue delineado manualmente y la medición del área de interés se estimó sobre imágenes ocultas. Después, se añadieron las mediciones de área de todas las secciones para estimar el volumen total. Las concordancias entre el estudio histológico y los hallazgos de la TC se compararon en cuanto a precisión, repetibilidad y confiabilidad. Se utilizaron las medidas de coeficiente de similitud de Jaccard y Dice como métrica de validación estadística para evaluar el desempeño del asesor en la medición manual del volumen. Se observó una buena correlación del evaluador con los valores medios de Dice, por encima de 0,8 indicando que es factible obtener mediciones coherentes y confiables de volumen. El protocolo propuesto ha demostrado ser preciso para calcular el volumen de la CT, y por lo tanto se puede utilizar para la planificación prequirúrgica asistida o para el diagnóstico de alteraciones estructurales en la CT.
Subject(s)
Humans , Infant, Newborn , Ear, Middle/anatomy & histology , Ear, Middle/diagnostic imaging , Tomography, X-Ray Computed , CadaverABSTRACT
Objective:To research the clinical application of tympanic cavity ventilation tube placement in canal wall down tympanomastoidectomy. Method:There were 52 patients with otitis media received canal wall down tympanomastoidectomy. We placed ventilation tube in posterior hypotympanum during the surgery. After surgery, all patients were followed up in 12 days, 1 month, 2 months, 6 months, and 1 year. The ventilation tubes were withdrew 6 months later, and then the hearing level and tympanic cavity status was evaluated after another half year. Result:All cases were followed up at least 1 year after surgery. Forty-four patients' tubes were removed 6 months later, but other 8 tubes had been extruded within 1 to 3 months. After 1 year, all 52 cases of ears were dry; 39 patients' tympanic membranes were stable, the postoperative complications included tympanic membrane retraction in 7 cases, middle ear effusion in 4 cases, and tympanic membrane perforation at anterior-inferior quadrant in 2 cases; CT examination indicated that 39 patients' aeration between tympanic cavity and Eustachian tube bony portion was normal, 9 patients' tympanic cavity aeration was smaller, and 4 patients' cavity was obstructed; 52 patients' average air conduction thresholds were 12.5 dB lower than that of preoperation. Conclusion:One-stage tympanic cavity ventilation tube placement is a simple, safe and effective method in canal wall down tympanomastoidectomy for middle ear diseases with Eustachian tube severe stenosis or obstruction in bony portion.