tailieunhanh - Ebook Dhingra diseases of ear, nose and throat (6/E): Part 2

(BQ) Part 2 book "Dhingra diseases of ear, nose and throat" has contents: Laryngotracheal trauma, laryngeal paralysis, voice and speech disorders, cancer larynx, laryngeal paralysis, cortical mastoidectomy, radical mastoidectomy, diagnostic nasal endoscopy, endoscopic sinus surgery,. and other contents. | DISEASES OF LARYNX AND TRACHEA SECTION V SECTION OUTLINE 56. Anatomy and Physiology of Larynx 57. Laryngotracheal Trauma 58. Acute and Chronic Inflammations of Larynx 59. Congenital Lesions of Larynx and Stridor 60. Laryngeal Paralysis 61. Benign Tumours of Larynx 62. Cancer Larynx 63. Voice and Speech Disorders 64. Tracheostomy and Other Procedures for Airway Management 65. Foreign Bodies of Air Passages 281 56 Anatomy and Physiology of Larynx ANATOMY OF LARYNX The larynx lies in front of the hypopharynx opposite the third to sixth cervical vertebrae. It moves vertically and in anteroposterior direction during swallowing and phonation. It can also be passively moved from side to side producing a characteristic grating sensation called laryngeal crepitus. In an adult, the larynx ends at the lower border of C6 vertebra. LARYNGEAL CARTILAGES Larynx has three unpaired and three paired cartilages. Unpaired: Thyroid, cricoid and epiglottis. Paired: Arytenoid, corniculate and cuneiform. 1. Thyroid. It is the largest of all (Figure ). Its two alae meet anteriorly forming an angle of 90° in males and 120° in females. Vocal cords are attached to the middle of thyroid angle. Most of laryngeal foreign bodies are arrested above the vocal cords, . above the middle of thyroid cartilage and an effective airway can be provided by piercing the cricothyroid membrane—a procedure called cricothyrotomy. 2. Cricoid. It is the only cartilage forming a complete ring. Its posterior part is expanded to form a lamina while anteriorly it is narrow forming an arch. 3. Epiglottis. It is a leaf-like, yellow, elastic cartilage forming anterior wall of laryngeal inlet. It is attached to the body of hyoid bone by hyoepiglottic ligament, which divides it into suprahyoid and infrahyoid epiglottis. A stalk-like process of epiglottis (petiole) attaches the epiglottis to the thyroid angle just above the attachment of vocal cords. Anterior surface of epiglottis