Q: At what vertebral level does the thyroid gland lie? A: 5th cervical to 1st thoracic. Q: What connects the right and left lobes of the thyroid gland? A: A narrow median isthmus. Q: Approximately how much does the thyroid gland weigh? A: 25 g. Q: True or false? The lobes of the thyroid gland extend as far superiorly as the thyroid notch? A: False. The lobes of the thyroid gland extend as far superiorly as the oblique lines on the laminae of the thyroid cartilages. Q: True or false? The lobes of the thyroid gland extend as far inferiorly as the 1st or 2nd tracheal cartilages? A: False. The lobes of the thyroid gland extend as far inferiorly as the 4th or 5th tracheal cartilages Q: The lateral thyroid ligament runs between which two structures? A: The posteromedial aspect of the lobe of the thyroid gland and the side of the cricoid cartilage. Q: The lateral aspect of the thyroid gland is covered by what muscle? A: The sternothyroid muscle. Q: The parathyroid glands are related to which surface of thyroid gland? A: The posterior surface. Q: Name the major relations of the thyroid gland: anterior, medial, lateral and posterior. A: Anterior : sternothyroid and sternohyoid muscles. Medial : larynx, trachea, external and recurrent laryngeal nerves and the oesophagus. Lateral : carotid sheath and its contents. Posterior : larynx, pharynx and oesophagus. Q: What arteries supply the thyroid gland? A: Superior thyroid artery from the external carotid artery and inferior thyroid artery from thyrocervical trunk (a branch of the subclavian artery). Q: What veins drain the thyroid gland? A: The superior and middle thyroid veins drain to the internal jugular vein, the inferior thyroid vein drains into the left brachiocephalic vein. Q: What is the parasympathetic nerve supply for the thyroid gland? A: The vagus nerve. Q: What is the sympathetic nerve supply for the thyroid gland? A: The postganglionic fibres from the superior, middle and inferior cervical sympathetic ganglia. Q: What anatomical structure extends from the tongue to the trachea and lies at the level of the 3rd to 6th cervical vertebrae in adult males? A: The larynx. Q: Name the major relations of the larynx: anterior, lateral and posterior. A: Anterior : Thyroid gland isthmus, infrahyoid, sternohyoid, sternothyroid and omohyoid muscles. Lateral : Carotid sheath and contents, thyroid gland, infrahyoid and sternocleidomastoid muscles. Posterior : Laryngopharynx, prevertebral muscles, prevertebral layer of fascia and the vertebral bodies. Q: Name the six types of lyngeal cartilages. A: Thyroid, cricoid, arytenoid (x2), corniculate (x2), cuneiform (x2) and epiglottic. Q: Which is the largest of the laryngeal cartilages? A: The thyroid cartilage. Q: The thyroid cartilage is composed of two laminae. The inferior 2/3 of these laminae are fused anteriorly in the median plane to form a projection called the what? A: Laryngeal prominence. Q: When comparing men and women, there is a difference in the angle in which the anterior borders of the two laminae of the thyroid cartilage fuse. In men the larger laryngeal prominence, the greater length of vocal cords and the resultant deeper pitch of the voice are all associated with a smaller or larger thyroid angle? A: A smaller angle. (90 degrees in men, 120 degrees in women) Q: Which laryngeal cartilage is classically described as being shaped like a signet ring? A: The cricoid. Q: Which laryngeal cartilage has quadrate posterior laminae and a narrow anterior arch and articulates with the inferior cornua of the thyroid cartilage? A: The cricoid. Q: Which ligament connects the thyroid cartilage and the cricoid cartilage? A: The anterior (median) cricothyroid ligament. Q: Which laryngeal cartilage possesses the laryngeal prominence? A: The thyroid. Q: Which laryngeal cartilage comes in a pair, is pyramidal in shape, has 3 surfaces, a base and an apex which articulates with the corniculate cartilage? A: The arytenoid. Q: Which laryngeal cartilage has a base with both a muscular process (laterally) and a vocal process (anteriorly)? A: The arytenoid. Q: Which laryngeal cartilage comes in a pair and is made of elastic fibrocartilage, articulates with the arytenoid cartilage (may even be fused to it in some cases) and lies posteriorly of the aryepiglotic mucosal folds? A: The corniculate. Q: Which laryngeal cartilage comes in a pair, is an elongated club like fibrocartilage and lies in the aryepiglottic folds anterior to the corniculates? A: The cuneiform. Q: Which laryngeal cartilage (of which there is only one in the body) is made of elastic fibrocartilage and projects behind the tongue in front of the laryngeal inlet? A: The epiglottic. Q: Which laryngeal cartilage has its sides attached to the arytenoid cartilages by the aryeppiglottic folds and has its rounded free end joined to thyroid cartilage by a ligament? A: The epiglottic. Q: Median glosso-epiglottic and lateral glosso-epiglottic folds connect the anterior surface of the epiglottis to what? A: The back of the tongue and the lteral pharyngeal wall respectively. Q: Describe the cricothyroid joint. A: It is a synovial joint with a cpsular ligament strengthened posteriorly by a fibrous band. The cricoid rotates on the inferior cornu around the transverse axis passing through both joints. There may also be some gliding. Q: Describe the cricoarytenoid joint. A: * It is a joint between the facets on the lateral part of the upper border of the cricoid cartilage lamina and the bases of the arytenoids. * It is strengthened by a capsular ligament and a strong posterior cricoarytenoid ligament. * It permits rotation of the arytenoid about an oblique axis, so that each vocal process swings laterally or medially. * It also permits a lateromedial gliding movement so that arytenoids approach or retreat from eachother. * In this joint medial gliding is associated with medial rotation and lateral gliding is associated with lateral rotation. Q: What are the two extrinsic ligaments/membranes of the larynx? A: The thyrohyoid membrane and the hyoepiglottic ligament. Q: What are the two intrinsic ligaments of the larynx? A: The cricothyroid ligament and the vestibular ligament. Q: This ligament forms the inferior part of the laryngeal membrane. The thickened superior edges of this ligament's complex extend from the apices of the arytenoid vocal processes to the dorsal aspect of the thyroid angle at about its midpoint and form the basis of the vocal folds. What ligament fits the above description? A: The cricothyroid ligament. Q: Where does the vestibular ligament of the larynx extend from and to? A: From the thyroid angle below the epiglottic cartilage to the anterolateral arytenoid surface above the vocal process. Q: What are the 3 sections of the larynx as divided by the vestibular and vocal folds? A: The laryngeal vestibule (superiorly), the ventricle (between) and the infraglottic region (inferiorly). Q: What structures bbound the laryngeal inlet? A: The upper edge of the epiglottis (anteriorly), the aryepiglottic folds (laterally) and the interarytenoid fold (posteriorly). Q: What laryngeal cartilages causes the anterosuperior swellings in the aryepiglottic folds? A: The cuneiforms. Q: What laryngeal cartilages causes the posteroinferior swellings in the aryepiglottic folds? A: The corniculates. Q: What is the fissure between the vestibular folds called? A: The rima vestibuli. Q: What is the fissure between the vocal folds called? A: The rima glottidis or rima glottis. Q: Anteriorly in the laryngeal sinus, there is a space which ascends between the vestibular ligament and the thyroid cartilage, what is that space called? A: The laryngeal saccule. Q: What limits the rima glottidis posteriorly? A: Mucosa passing between the arytenoid cartilages. Q: What are the two parts of the rima glottis? A: The intermembranous part and the intercartilagenous part. Q: What are the 2 groups of intrinsic laryngeal muscles? A: Muscles of laryngeal inlet and muscles of the vocal folds. Q: What action do the muscles of laryngeal inlet perform? A: They allow closure of the laryngeal inlet during swallowing. Q: What are the muscle of the laryngeal inlet? A: The aryepiglottic, the oblique arytenoid and the transverse arytenoid. Q: What are the muscles of the vocal folds? A: The lateral cricoarytenoid, the posterior cricoarytenoid, the cricothyroid and the thyroarytenoid/vocalis. Q: What is the action of the lateral cricoarytenoid muscle? A: Adduction of the vocal folds. Q: What is the action of the posterior cricoarytenoid muscle? A: Abduction of the vocal folds. Q: What is the action of the vocalis/thyroarytenoid muscle? A: Relaxation of the vocal ligament. Q: What is the action of the cricothyroid muscle? A: It tilts the thyroid cartilage down. Q: What is the arterial blood supply of the larynx? A: The superior and inferior thyroid arteries. Q: What is the venous drainage of the larynx? A: Superior and middle thyroid veins drain into internal jugular vein and inferior thyroid vein drains to left brachiocephalic vein. Q: Which nerve divides to form the internal and external laryngeal nerves? A: The superior laryngeal nerve. Q: What is the motor nerve supply for the cricothyroid and cricopharyngeus muscles? A: The external laryngeal nerve. Q: What does the internal laryngeal nerve supply? A: Sensory supply to the mucouc membrane above the vocal folds, epiglottis and thyrohyoid membrane. Q: What motor supply does the recurrent laryngeal nerve contribute? A: All the intrinsic muscles of the larynx except the cricothyroid. Q: What is the sensory supply for the mucous membranes below the vocal folds? A: The recurrent laryngeal nerve. Q: Where does the parasympathetic supply to the larynx come from? A: CN X (vagus) both sensory and motor. Q: What are the sympathetic ganglia which supply the larynx? A: The superior and middle cervical ganglia. Q: What are the three requirements for speech (according to ANAT2007 Visceral Anatomy for medical students by Dr Ken Ashwell)? A: 1. A source of energy (expired air). 2. Structures capable of periodic and aperiodic oscillation (vocal folds). 3. A resonator (the column of air extending from the vocal folds to the lips and nostrils).