Zur Anatomie von Glottis und Subglottis beim kindlichen Kehlkopf

BACKGROUND: The morphological development of the human larynx during the first years of life has previously not been studied in detail and has mainly been described on a qualitative basis. This study seeks to provide detailed morphometric data on the regular anatomy of the vocal cords, the subglottic airway and the tracheal airway dimensions gained from plastinated whole organ serial sections of 43 infant larynges and to determine morphological changes with age. Such information may be useful for the understanding of pediatric airway disease or for laryngeal surgery in children. MATERIAL AND METHODS: The larynges of 43 children aged 1 to 60 months were plastinated. Whole organ serial sections were obtained by cutting the resulting specimen with a diamond band saw. Morphometry of whole-organ sections was accomplished using a high resolution, computer-based image analyzer. The total length of the glottis, length of the cartilaginous and ligamentous glottis, subglottic cartilaginous cross-section, subglottic airway and tracheal airway were determined for each specimen. RESULTS: The subglottic airway increases considerably in size during the first 2 years of life (from 13 to 28 mm2 in the means). Further growth seems to follow a linear mode. The relative proportion of the mucosal lining of the subglottic airway decreases likewise. While it occupies approximately 50% of the subglottic cartilaginous cross-section during the first two years of age, its relative proportion decreases to some 30 to 40% between age three to five. Other than in adults, and comparable to most mammals, the cartilaginous glottis accounts for 60 to 75% of the vocal folds' length in children under two years of age. The anterior ligamentous part of the glottis outsizes its posterior cartilaginous portion during the third year of life. CONCLUSION: This study supplies detailed morphometric data on the growth and structure of the human larynx during the first years of life that have not been available to date. Previous studies on the anatomical configuration of the infant larynx have focused on the the perinatal larynx, the prepuberal and puberal larynx, and the development of collagen fibres in the developing larynx. The human larynx has undergone significant evolutionary adaptations. Among them are the descent of the larynx, the capability of vocal fold adjustment in length, tension and shape, and the prominent configuration of the membranous part of the vocal folds as opposed to the cartilaginous part. The infant larynx is not just a miniature of the adult organ. It shows differences in its position relative to the vertebrate column, in the composition of cartilages and soft tissues, and in environmental adaptation. The present study is the first to supply detailed morphometric data on the growth and structure of the human larynx during the first five years of life and on the morphological changes of the larynx during this period. From these data it seems that some of the adaption of the human larynx as opposed to other vertebrates are not fully developed at birth, but undergo postnatal maturation. The relative proportions of the cartilaginous and membranous parts of the vocal folds clearly demonstrate this maturation process: While the posterior "respiratory" glottis accounts for some sixty to 75% of the total glottic length in newborns, its relative proportion decreases throughout the first years of life and finally equals the proportions of the adult larynx. Other than in adults, and in accordance with the literature, no sexual dimorphism of the larynx could be detected in this series of infant larynges. Morphometric data on the growth and structure of the human vocal folds and the subglottic airway during childhood are presented. Plastinated whole organ serial sections were used in the study to show the infant laryngeal morphology. The study provides quantitative anatomical data of clinical interest that light up the anatomy of the pediatric airways.     

Persistence of injectable collagen in the human larynx: a histopathologic study

This is a report of the histologic findings in a human larynx that had undergone collagen injection for glottic insufficiency 14 months prior to autopsy. The patient's management before augmentation with collagen included extended supraglottic laryngectomy, radiation therapy, and Polytef injection. Connective tissue changes secondary to other forms of treatment were apparent bilaterally and changes limited to the site of collagen injection were identified. There have been reports of persistence of injected collagen in the canine larynx at 1 year but this is the only study documenting persistence in a human subject. The implant appeared homogeneous and was easily distinguished from host collagen and the reactive fibrosis associated with particulate Polytef. These findings are similar to those observed in the canine model and suggest that there is persistence of injected collagen in the human larynx.     

Postnatal developmental changes in inner ear ornithine decarboxylase (ODC).

Ornithine decarboxylase (ODC), the rate-limiting enzyme in polyamine synthesis, is important in cellular growth, differentiation and development. Although ODC has been quantitated in cochlear tissues of the adult rat, it has not been assessed quantitatively in developing inner-ear tissues. The purpose of the present study was to quantitate ODC in cochlear tissues of the rat during the period of development of hearing. Cochlear ODC was significantly elevated throughout the period of cochlear maturation in that it increased rapidly during the first 10 days, peaked on day 10 and then declined thereafter. ODC in the lateral wall/organ of Corti tissues was significantly higher than in the cochlear nerve in developing, but not in adult rats. Further examination of separate cochlear tissues from 10-day old rats revealed that ODC activity was higher in the organ of Corti than in the lateral wall or cochlear nerve. Postnatal changes in ODC paralleled functional maturation of hearing and the hypersensitive period for aminoglycoside ototoxicity in the rat. Since aminoglycosides have been shown to inhibit ODC in vitro, aminoglycoside inhibition of polyamine synthesis may mediate the hypersensitivity of developing animals to the effects of these drugs.     

Morphology of the human larynx during the first five years of life studied on whole organ serial sections

The morphologic development of the human larynx during the first years of life is poorly understood to date. This study used plastinated whole organ serial sections to determine the growth and structure of the infant larynx. The larynges of 43 children 1 to 60 months old were plastinated. Whole organ serial sections were obtained by cutting the resulting specimen with a diamond band saw. The slices were then submitted to computer-assisted morphometric investigation. We found that the subglottic airway rapidly increases in size during the first 2 years of life. Further growth follows a linear mode. The relative proportion of the mucosal lining decreases likewise. In contrast to that in adults, and comparable to that in most mammals, the cartilaginous glottis accounts for 60% to 75% of the vocal folds' length at <2 years. No sexual dimorphism of the larynx exists during childhood. This study supplies detailed morphometric data on the growth and structure of the human larynx during the first years of life. It is the first to use plastinated whole organ serial sections for morphology of the pediatric larynx. Therefore, this study provides quantitative anatomic data of clinical interest that have not been available to date.     

Genetic characteristics of hearing disorders in changes in genes responsible for collagen synthesis

The latest clinicogenetic studies of different hypoacusis forms associated with defects in collagen synthesis are reviewed. To 2002 in human cochlear the researchers got to know gene expression of 10 types of collagens. Basal membrane of the Corti's organ is formed by collagen of type IV, bone cochlear capsule - by collagen of type I, the tectorial membrane contains collagens of type II, V, IX and XI. Brief clinical and genetic characteristics of Alport syndrome, Stickler syndrome, stapes ankylosis syndrome, OSMED syndrome, osteogenesis imperfecta are provided. The results of the study confirm the fact that collagen, being a basic structural component of the connective tissue, has an essential role in development of normal hearing. Accurate diagnosis of the above syndromes is sure to improve quality of treatment.     

Combined glottographic changes in the elderly.

This study investigates by combined glottography the effect of the anatomical changes of ageing on laryngeal movement during the vibratory cycle. 10 adult males less than 25 years of age were compared to 10 males over 60 years of age. The speed quotient was increased in the elderly group; thus, ageing in the larynx results in a slowing of the opening of the vocal folds. This may account for the different voice quality in the elderly. The clinician must consider the subject's age when interpreting speed quotient values.     

Comparative anatomy of human and sheep laryngeal skeleton

In a macroscopical study the dimensions of the adult laryngeal skeleton of man and sheep were compared. In both species the data for male and female were evaluated separately. In contrast to pronounced differences in size between male and female human larynges, the dimensions of both sexes in sheep proved to be very similar. In respect of 7 size values, the sheep larynx falls in the range between the male and female human larynx. This applies to most values for height, the antero-posterior diameter and the inferior breadth of the thyroid cartilage. In the sheep cricoid, the height of the lamina and the inner transverse diameter correspond closely to the human counterpart. The most conspicuous differences vis-à-vis the human larynx are the narrowing of the upper portion, the absent upper incisure of the thyroid and the relatively large dimensions of the arytenoid cartilages in sheep. Since in sheep the dimensions at the level of the glottis and of the subglottic space are within the range of the human larynx, the suitability of the sheep larynx as a model for experimental clinical laryngology is discussed.     

Does Hyaluronic Acid Distribution in the Larynx Relate to the Newborn's Capacity for Crying?

Objectives/Hypothesis: The newborn is heavily dependent on voice communication and therefore has relatively higher vocal demands and expenditures than the adult, the loudness output per mass performance exceeds that of the adult, and the newborn larynx exhibits significant histological and biochemical differences. The neonatal larynx is capable of sustaining relatively greater pitch and loudness than the adult over longer periods of time. This ability may be related to a more compact arrangement of collagen within the lamina propria, less interstitial space, and a uniform distribution of hyaluronic acid (HA). As HA is the primary determinant of vocal fold viscosity and water content, the distribution of HA in the superficial portion of the neonatal vocal fold is hypothesized to be related to newborn crying endurance. Our objective was to examine the histological structure and the quantity and arrangement of HA within the lamina propria of the pediatric larynx and review the relevant physiology of hyaluronic acid and its impact on voice production. Study Design: Histological and digital subtraction analysis. Methods: Intact, neonatal larynges were sourced from fresh cadaveric specimens. Trichrome stain was used to assess the collagen content and location in the tissues. HA was stained using a colloidal iron staining technique with and without incubation with bovine testicular hyaluronidase. Average optical density was calculated in tissue before and after treatment with hyaluronidase, and the stain intensity ratio was calculated. Results: A total of 14 larynges were suitable for examination, eight males and six females. Histological examination revealed a uniform appearance of the vocalfold without evidence of a distinct vocal ligament or layered structure. Colloidal iron staining revealed an even distribution of HA throughout the vocal fold with no significant difference between quadrants. Images of the colloidal iron-stained tissue had a mean pixel intensity of 82 of 255. Slides of vocal fold tissue treated with hyaluronidase revealed a pixel intensity of 106 of 255 for a 22% mean difference in stain intensity (P < .01). Conclusions: The identification of the layered structure of the adult lamina propria has raised a number of questions as to the development and purpose of the human larynx. Based on histological observations from the current study, possible explanations for the physiological differences include differences in the distribution and tissue concentration of HA and consequently dynamic viscosity, oncotic affinity for water, and less intercellular space in the superficial lamina propria.     

Visualization of the human larynx: a three-dimensional computer modeling tool

The larynx is a complex compact organ. A detailed understanding of the anatomical relationships of its various structures is critical to the various workers in the field. To facilitate this goal, a 3-D model of the human larynx has been developed using multiple thin section MRI and CT images taken through a cadaver larynx. A databank of individual laryngeal structures (`units') has been built up. A software package has then been utilized which allows for representation of any of the stored `units'. In this manner, elements of the larynx can be viewed from any direction, with the larynx static or in motion. Similarities and differences from current CD-ROM packages of the larynx are discussed.     

Fifteenth Daniel C. Baker, Jr, memorial lecture. What have whole organ sections contributed to the treatment of laryngeal cancer?

The study of whole organ sections of laryngectomy specimens has demonstrated the patterns by which cancer spreads from one part of the larynx and hypopharynx to another. These studies have also demonstrated the fibroelastic membranes and ligaments that form the boundaries of intralaryngeal compartments within which cancer is confined in its early stages. They thus have added support to the concept of partial laryngectomy for selected lesions and have illustrated the features of those types of laryngeal cancer that have not responded well to radiotherapy. Whole organ sections of laryngectomy specimens have allowed a more accurate interpretation of preoperative computed tomography and magnetic resonance imaging and have provided a reliable basis for clinical staging.     

Age-related changes in the murine larynx: initial validation of a mouse model

OBJECTIVES: Changes in voice are commonly associated with aging (presbyphonia). Age-related voice change significantly impairs elderly individuals' ability to communicate meaningfully with others and affects their quality of life. With changing age demographics in our society and increasing emphasis on quality of life, treatment of presbylaryngis is becoming more paramount. METHODS: We used 9 aged and 9 young mice to validate a mouse model for the aging larynx. We stained the larynges with Alcian blue to determine the hyaluronic acid content, trichrome stain to determine the collagen content, and immunohistochemical stain for alpha smooth muscle actin to determine the myofibroblast content. Morphometric measurements were performed for muscle area, muscle thickness, and muscle fiber diameter. RESULTS: Statistically significant differences in the density measurements of hyaluronic acid and collagen reflected decreased hyaluronic acid and increased collagen content in the aging larynx. We found alpha smooth muscle actin-labeled myofibroblasts only in the aged larynges. No statistically significant differences were found in the morphometric measurements. CONCLUSIONS: Aged mice may make a practical model for the age-related changes in the vocal folds that can be used further in studies aiming to correct these changes.     

Stan spoidła przedniego u chorych na raka krtani

Aim of the workAssessment of directions and ways of cancer spreading in the anterior commissure of the larynx, depending on the tumor location, age, sex of patients in a clinical trial and in microscopic serial section study.Materials and methodsThe study included 50 larynx preparations obtained from open partial and total laryngectomies (F-7; M-43). For the assessment of larynx anterior commissure microscopic status 28 larynx preparations with macroscopic free anterior commissure were used. For study of the directions and ways of tumor spreading in the anterior commissure served 22 larynx with macroscopic infiltration of anterior commissure. Anterior Commissure (AC) and TNM classifications was used to determine the location and tumor stage. Larynx anterior commissure was extracted and divided into 3 subregions: supraglottic, glottic and subglottic.ResultsThe direction and the way of cancer propagation in larynx anterior commissure structures is dependent on morphological changes that occur with aging. Cancer spreads in the anterior commissure along the fibers anchoring voice muscle within the Broyles ligament and is seen in tumor cells microembolism.ConclusionsIn patients with cancer of the larynx without macroscopically visible neoplastic lesions in the anterior commissure, cannot be excluded its microinfilration. Changed with age anterior commissure’ Broyles ligament by the process of neovascularization and ossification is not an effective protection against the spread of cancer. Directions and the ways of cancer spread in the anterior commissure is similar in men and women. AC classification can be important in qualifying patients for organ preservation surgery and should be supplemented by an additional AC4 degree, taking into account subglottic changes in the anterior commissure of the larynx.     

Acoustic assessment of voice signal deformation after partial surgery of the larynx

OBJECTIVE: The main objective of the present study was to assess the degree of voice signal impairment among patients who had undergone partial surgery of the larynx due to cancer of this organ. Such on evaluation may be helpful in the selection of the optimal surgical technique for the treatment of tumors displaying a varying degree of local advancement. METHODS: A prospective examination was carried out among 128 patients. Additionally a comparative study of the control group consisting of 36 healthy males was carried out. Acoustic tests were carried out in an echo-free chamber. The temporal changes in the value of acoustic pressure of the uttered text were registered. The 'distance' between the normal speech signal and the pathological voice has been established. RESULTS: The values of the fundamental frequency increase together with an increase of the range of resection of anatomical structures. The biggest differences in the value of results describing the distance from the standard were observed after hemilaryngectomy. The shortest distance from the acoustic standard was observed after chordectomy. No significant differences in the degree of voice signal impairment among patients who had undergone extended chordectomy and hemilaryngectomy were observed. CONCLUSION: The above findings can be of help in arriving at an optimum solution in cases of partial surgery of the larynx. The problem is particularly important in situations where there is the choice between different types of surgery.     

A three-dimensional reconstructive study of the layer structure of the human vocal cord

Summary The purpose of this investigation was to clarify the detailed histological structure of the human larynx and to clarify the cause of adaptation in high-frequency vibrations using three-dimensional histological reconstructions of human true vocal cords. In a first series of studies, 54 intact adult larynges were obtained from 398 human cavaders with known histories. Four of these laryngeal specimens were fixed in 10% formalin. Three of these were decalcified and embedded in paraffin and the other in Technovit-7100. The layer structure of each larynx was investigated with a three-dimensional reconstruction method using a personal computer. Results demonstrated that the elastic fiber layer in the superior surface of the vocal cord was wider than that in the inferior surface. The collagen fiber layer extends from the anterior commissure in a posterior direction. The elastic fiber layer connected both the anterior and the posterior macula flava, while the collagen fiber layer connected the thyroid cartilage and the anterior macula flava.     

Professional dysphonia and its risk factors in the material of the outpatient clinic of the Department of Otolaryngology, Medical Academy of Białystok

Occurrence of professional dysphonia was analysed in a group of 309 patients treated in the Phoniatric Outpatient Clinic, Department of Otolaryngology, Medical Academy in Bia?ystok through the period of 1999-2001. In a group of professional voice users female teachers of primary schools and lower secondary schools predominated. Obtained results were compared with those from a group of 65 persons of other occupations. In the both groups other harmful factors affecting the voice organ were excluded. The clinical assessment included subjective and objective laryngological examination using videolaryngostroboscopy. The clinical material was evaluated in a view of functional and organic disorders of the voice organ. Early occurrence and aggravation of functional changes in the larynx was recorded in non professional voice users in the course of their seniority. In professional patients organic changes were more common and occurred earlier than functional disorders. Severity of dysphonia was related to the larynx pathology, especially of a functional character.     

Effects of aging and gender on interhemispheric function.

The ability of the two hemispheres of the brain to communicate with one another via the corpus callosum is important for a wide variety of sensory, motor, and cognitive functions, many of them communication related. Anatomical evidence suggests that aging results in structural changes in the corpus callosum and that the course over time of age-related changes in corpus callosum structure may depend on the gender of the individual. Further, it has been hypothesized that age- and gender-related changes in corpus callosum structure may result in concomitant decreased performance on tasks that are reliant on interhemispheric integrity. The purpose of this study was to investigate the effects of age and gender on auditory behavioral and visuomotor temporal indices of interhemispheric function across the life span of the normal adult. Results from 120 consistently right-handed adults from age 20 to 75 years revealed that interhemispheric integrity, as measured by dichotic listening, auditory temporal patterning, and visuomotor interhemispheric transfer time tasks, decreases relatively early in the adult life span (i.e., between the ages of 40 and 55 years) and shows no further decrease thereafter. In addition, the course over time of interhemispheric decline is different for men compared to women for some tasks. These findings suggest that decreased interhemispheric function may be a possible factor contributing to auditory and communication difficulties experienced by aging adults. In addition, results of this study hold implications for the clinical assessment of interhemispheric function in aging adults and for future research into the functional ramifications of decreased multimodality interhemispheric transfer.     

Combined glottographic changes in the elderly

This study investigates by combined glottography the effect of the anatomical changes of ageing on laryngeal movement during the vibratory cycle. 10 adult males less than 25 years of age were compared to 10 males over 60 years of age. The speed quotient was increased in the elderly group; thus, ageing in the larynx results in a slowing of the opening of the vocal folds. This may account for the different voice quality in the elderly. The clinician must consider the subject's age when interpreting speed quotient values.     

Panel on epidemiology and etiology of laryngeal carcinoma.

Ours is a developing country. We have still not controlled the common infectious diseases which are extinct in the West; therefore, our limited resources are spent on study of epidemiology of infectious diseases. My conclusions on epidemiology of cancer of the larynx are drawn from observations made of the clinical material over a period of 25 years. I have come to the conclusion that the smoked tobacco and the slaked lime in the Indian "Pan" are the two important carcinogenic agents. Poor nutrition appears to be carcinogenic. It requires study and confirmation at a cellular level. Misuse of voice does seem to be the cause of laryngeal cancer. Racial, genetic and other environmental factors, including pollution have not contributed to the increased incidence of laryngeal cancers. The common histological types of laryngeal cancer are known. My observations on certain biological behavior of the tumor have been helpful. 1. An exophytic growth is less infiltrative; its metastatic mass reflects the same characteristics. 2. Certain anaplastic tumors can flout all laws of cancer spread and metastasize in distal organs. 3. Presence of reticular hyperplasia in peripheral lymph nodes is of good prognostic value.     

Immunohistochemical distribution of extracellular matrix components and keratin in experimentally induced otitis media.

The distribution of collagen types I, III, and IV and of laminin, fibronectin, and keratin was studied in otitis media experimentally induced by Streptococcus pneumoniae in the chinchilla. The expression of interstitial collagen types I and III and of fibronectin was increased in the subepithelial space that was thickened by inflammation in the acute period of infection. The expression of collagen type IV in the subepithelial space could be seen in the early period. The epithelial cells in the middle ear changed from flat cuboidal to pseudostratified columnar in pneumococcus-inoculated ears, and the number of keratin-positive epithelial cells in the middle ear increased remarkably after infection. These results indicate that changes in epithelial cell differentiation effected by the extracellular matrix correlate with changes in expression of keratin. It is proposed that the extracellular matrix may contribute to tissue repair in the middle ear after bacterial infection by interfering with cell proliferation of epithelial cells and fibroblasts.     

Age related changes in the distribution of laryngeal glands in the human adult larynx

OBJECTIVE: To understand the defense status of glandular tissue in the human adult larynx, we examined the glandular distribution, concentration and the ratio of the mucous glands in the subglottic and supraglottic larynx. METHODS: One-hundred and seven adult larynges were examined. The area of the mucosa and glands were measured using an image analyzing system. The correlations of the concentration as well as the ratio of the mucous glands with age were analyzed. RESULTS: The ratio of the areas occupied by the glandular acini of the subglottis was almost equal to that of infants as we reported earlier. The concentration of the laryngeal glands decreased in higher-aged adults at the level of the supraglottis, but not at the level of the subglottis. CONCLUSIONS: In comparison to infants, the ratio of laryngeal glands of the human subglottic larynx is rather constant in human adults. However, the supraglottic larynx seems to be influenced by increasing age. The changes deserved in the laryngeal glands predominantly occur in the supraglottic larynx.