The larynx
Rogan J Corbridge in Essential ENT, 2011
The main function of the larynx is to act as a sphincter to protect the lower airways from contamination by foods, liquids and secretions. It also allows the production of an effective cough, which is essential in clearing unwanted matter from the airway. In humans, the larynx has evolved as a highly complex organ for the production of sound vibrations. The larynx is essentially a tube made up of a series of cartilages and bone, which are held together by interconnecting membranes, ligaments and muscles. Any disease process affecting the larynx may interfere with the function of this organ. Thus, diseases of the larynx present with either voice or airway problems, or not infrequently a combination of both. The vocal cords appear reddened and oedematous; often the whole larynx is generally inflamed, with swelling of the arytenoids and false cords, and the epiglottis may appear red at its tip.
- Isolation of Primary Chondrocytes from Bovine Articular Cartilage
Melissa Kurtis Micou, Dawn Kilkenny in A Laboratory Course in Tissue Engineering, 2013
Hyaline cartilage is found in the nasal septum, sternum, trachea, larynx, and on the articulating surfaces of long bones, where it is referred to as articular cartilage. Articular cartilage distributes loads and functions as a bearing surface in joints such as the hip and knee. The ECM of hyaline cartilage is composed primarily of collagen type II and is rich in proteoglycans. Elastic cartilage is present in the epiglottis, external ear, and larynx. The ECM of elastic cartilage contains elastin and collagen type II with less proteoglycan than hyaline cartilage. Fibrocartilage is found in the intervertebral disc, the meniscus of the knee, and at the insertion of ligaments and tendons. The ECM of ¦brocartilage is composed primarily of collagen type I.
Intubation and management of airway haemorrhage
Pallav Shah in Atlas of Flexible Bronchoscopy, 2011
Fig. 12.2c Sequence of images demonstrating intubation: endotracheal tube inserted into the trachea. In our experience, with adequate topical anaesthesia patients have tolerated an endotracheal tube for up to 1 hour with minimal conscious sedation (0-5 mg midazolam intravenously). The main caution is to avoid forcing the endotracheal tube against resistance, which is often due to the endotracheal tube being caught around the epiglottis or the vocal cords. Forceful insertion may lead to some trauma of the vocal cords (Fig. 12.3).
Biomechanics of the Human Epiglottis
Published in Acta Oto-Laryngologica, 1979
B. Raymond Fink, Roy W. Martin, Charles A. Rohrmann
The mechanism that folds the epiglottis down over the closed larynx in the course of swallowing has been unclear. Measurements of the force needed to fold the epiglottis in cadaver specimens exceed the estimated force available from the aryepiglottic muscle. Frame-by-frame analysis of cinefluorograms reveals that deglutitional epiglottic downfolding occurs at the time of maximal elongation of the hyoepiglottic ligament. The observations lead us to propose a conical model of epiglottic downfolding which also explains the conical shape of the epiglottis usual in early infancy. The infant shape may be part of a protective partially closed entrance adaptive to suckling, while maturational widening of the opening adapts to the growing respiratory demands of increasing physical exertion.
A peculiar site of chondroma: The epiglottis
Published in Acta Oto-Laryngologica, 2005
Chondroma of the laryngeal cartilage is an uncommon benign cartilaginous neoplasm. The commonest location is the posterior lamina of the cricoid cartilage, followed by the thyroid cartilage. The occurrence of chondroma in the epiglottis is extremely rare. Depending on the size and location of epiglottic chondroma the clinical manifestations are variable and include a lump in the neck, difficulty in swallowing fluids and dyspnea. In this study, an additional rare case of chondroma arising in the epiglottis is reported. The mass was located over the tip of the epiglottis and caused no significant clinical manifestations except for a foreign body sensation in the throat. Endoscopic excision with an adequate free margin was achieved via suspension laryngoscopy under general anesthesia with intubation. The patient was disease-free during a 1-year follow-up period. We present this case to highlight the occurrence of this rare benign lesion in the epiglottis, and stress that it should not be neglected in the differential diagnosis of an epiglottic mass. Conservative surgical excision is the initial treatment of choice and long-term follow-up is necessary.
Ultrasonography versus conventional methods (Mallampati score and thyromental distance) for prediction of difficult airway in adult patients
Published in Egyptian Journal of Anaesthesia, 2020
B. S. Abdelhady, M. A. Elrabiey, A. H. Abd Elrahman, E. E. Mohamed
ABSTRACT Background The poor reliability of traditional screening tools to identify a potentially difficult airway makes the difficult laryngoscopy and tracheal intubation rate remains at 1.5–13%.The hypothesis is that fat pads affect the view during direct laryngoscopy so the increasing thickness of pretracheal soft tissue or pre-epiglottic space could be strong predictors of difficult laryngoscopy as the mobility of the pharyngeal structures is impaired. Upon that, we aimed to evaluate ultrasound-measured distance from skin to epiglottis for prediction of difficult laryngoscopy in Egyptian population. Methods This was a prospective single blind randomized clinical study conducted on 80 patients requiring general anesthesia.Preoperatively, airway evaluation was performed using three parameters including Mallampati score, thyromental distance and ultrasound-measured distance from skin to epiglottis at the level of thyrohyoid membrane. The primary outcome was to correlate ultrasound measured distance from skin to epiglottis with difficult laryngoscopy in Egyptian population using Cormack – Lehane grading. Results Difficult laryngoscopy group displayed greater thickness of the ultrasound measured distance from the skin to epiglottis(2 ± 0.3 cm versus 1.7 ± 0.3 cm; p = 0.002). The cut-off point for difficult laryngoscopy was >1.85 cm with sensitivity of 80%, specificity of 70.8% and area under the receiver operating characteristic curve was 0.759. Mallampati score and thyromental distance had poor area under the curve = (0.651, 0.670 respectively). Conclusion Our study revealed good correlation between ultrasonograohic measurement of the skin to epiglottis distance and Cormack-Lehane grade in Egyptian population, therefore it might be considered as a predictor of difficult laryngoscopy. Clinical trial number NCT03799055.
Related Knowledge Centers
- Elastic Cartilage
- Larynx
- Pharynx
- Mucous Membrane
- Mouth