medial portion of the cartilage of the auditory tube, which causes an elevation of the surrounding mucous membrane. The salpingopharyngeal fold, which is a vertical fold of mucous membrane, extends from the bottom portion of the torus and encompasses the salpingopharyngeus muscle. A secondary and rather diminutive fold, known as the salpingopalatine fold, extends from the supe­rior region of the torus to the palate. The pharyngeal recess, also known as the fossa of Rosenmülle r, is located posterior to the ostium of the auditory canal. The pharyngeal tonsil, sometimes referred to as a mass of lymphoid tissue, is located on the posterior wall. It is most prominent throughout childhood. The mucous membrane located above the pharyngeal tonsil has an irregular ask­shaped depression in the midline. Occasionally, this depression continues upward to the basilar process of the occipital bone. This anatomical feature is referred to as the pharyngeal bursa. The segment of the pharynx known as the pars oralis pharyngis extends from the soft palate to the hyoid bone. The orice of the structure is located in the front region, namely via the isthmus fau­cium, leading into the oral cavity. Positioned within the lateral wall, between the two palatine arches, is the palatine tonsil. The anatomical region known as the laryngeal part of the pharynx, or pars laryngea pharyngis, extends from the hyoid bone to the lower boundary of the cricoid carti­lage. At this point, it seamlessly transitions into the esophagus. The front aspect of the larynx exhib­its a triangular entry, with its base oriented toward the front. This entrance is comprised of the epiglottis, which forms the base, and the aryepiglottic folds, which represent the lateral limits. The laryngeal orice is anked by a recess known as the sinus piriformis. This recess is delimited medi­ally by the aryepiglottic fold and laterally by the thyroid cartilage and hyothyroid membrane. There is a total of six muscles that comprise the pharynx, as seen in Figure 1.14 . The muscles involved in the pharyngeal constrictor complex include the inferior constrictor, stylopharyngeus, middle con­strictor, salpingopharyngeus, superior constrictor, and pharyngopalatinus (Figure 1.19). The infe­rior constrictor, also known as the constrictor pharyngis inferior, originates from the lateral aspects of the cricoid and thyroid cartilage. It is the thickest of the three constrictor muscles. The structure in question originates from the cricoid cartilage, specically within the space located between the cricothyreoideus muscle anteriorly and the articular facet for the inferior cornu of the thyroid carti­lage posteriorly. The origin of the muscle on the thyroid cartilage is located at the oblique line on the lateral aspect of the lamina, extending from the posterior border and reaching the surface behind it,

and pharyngopalatinus muscles. The termination point of the structure is situated superiorly in the cornu and inferiorly in the cornu. The superior cornu is characterized by its elongated and slender shape, with an upward, backward, and medialward orientation. It terminates in a conical tip, serv­ing as the point of attachment for the lateral hyothyroid ligament. The inferior cornu is character­ized by its compact dimensions, exhibiting a shortened and robust structure. It is oriented in a downward direction, displaying a minor anterior and medial inclination. Additionally, it features a diminutive oval articular facet on its medial aspect, which facilitates articulation with the lateral surface of the cricoid cartilage. During infancy, the laminae of the thyroid cartilage are linked to each other by a narrow, lozenge-shaped strip, dubbed the intrathyroid cartilage. The aforemen­tioned strip spans from the superior to the inferior boundary of the central cartilage and is charac­terized by its increased transparency and exibility compared to the laminae. The cricoid cartilage, known as cartilago cricoidea in anatomical terminology, is smaller than the thyroid cartilage. However, it compensates for its reduced size by possessing greater thickness and strength. Functionally, it serves to constitute the lower and posterior regions of the larynx’s wall. The struc­ture is comprised of two distinct components: a posterior quadrate lamina and a rather slender anterior arch, which measures around one-fourth or one-fth of the depth of the lamina. The poste­rior portion of the lamina cartilaginis cricoideae is characterized by its deep and broad structure, measuring approximately 2–3 cm in a superior-inferior direction. Positioned on its posterior surface, in the midline, is a vertical ridge. The lower part of this ridge serves as an attachment site for the longitudinal bers of the esophagus. Additionally, on each side of this ridge, there is a wide depres­sion specically designed to accommodate the cricoarytenoideus posterior muscle. The front seg­ment of the arch, known as the arcus cartilaginis cricoideae, is characterized by its thin and convex shape. It has a vertical measurement ranging from 5 to 7 mm. This arch provides external attach­ment points for the cricothyreiodei muscles at the front and sides, and at the back, it attaches to a piece of the constrictor pharyngis inferior muscle. Located near the intersection of the lamina and the arch, there exists a diminutive circular articular surface on both sides, which facilitates the articulation with the inferior cornu of the thyroid cartilage. The inferior margin of the cricoid carti­lage is oriented horizontally and is anatomically linked to the uppermost ring of the trachea by the cricotracheal ligament. The superior boundary has an oblique upward and posterior trajectory, which can be attributed to the signicant depth of the lamina. The structure in question exhibits anterior attachment to the middle cricothyroid ligament, lateral attachment to both the conus elasti­cus and the cricoarytaenoidei laterales, and posteriorly, it displays a central shallow notch. On either side of this notch, there are smooth, oval, convex surfaces that are oriented in an upward and lateral direction. These surfaces serve as points of articulation with the base of an arytenoid cartilage. The inner surface of the cricoid cartilage has a smooth texture and is covered by a layer of mucous mem­brane. The arytenoid cartilages, also known as cartilagines arytaenoideae, consist of a pair of struc­tures located near the superior margin of the lamina of the cricoid cartilage, positioned posteriorly inside the larynx. Each object possesses a pyramidal structure, characterized by three distinct sur­faces, a foundational base, and a singular apex. The posterior aspect of the structure has a triangle shape, displaying a smooth and concave morphology. This surface serves as the site for the attach­ment of the arytaenoidei obliquus and transversus muscles. The anterolateral surface exhibits a moderate convexity and a coarse texture. Located in close proximity to the apex of the cartilage, there exists a rounded prominence known as the colliculus. Extending from this colliculus is a ridge referred to as the crista arcuata, which rst bends in a posterior direction before subsequently descending and then moving forward toward the vocal process. The inferior portion of this crest is situated between two concavities known as foveae, namely an upper triangular fovea and a lower oblong fovea. The latter fovea serves as the point of attachment for the vocalis muscle. The medial surface is characterized by its narrowness, smoothness, and attened shape. It is covered by a layer of mucous membrane and serves as the lateral border of the intercartilaginous portion of the rima glottidis. The cartilage base has a wide structure, including a concave and sleek surface that facili­tates articulation with the cricoid cartilage. The lateral angle of the structure is characterized by its short length, rounded shape, and notable prominence. It extends in a posterior and lateral direction, and is referred to as the muscular process. This particular region provides attachment points for the cricoarytenoid posterior muscle at its posterior aspect, and for the cricoarytenoid lateral muscle at its anterior aspect. The anterior angle, which is likewise notable but possesses a sharper tip, extends horizontally in a forward direction. It serves as the site of attachment for the vocal ligament and is referred to as the vocal process. The superior aspect of each cartilage has a pointed shape, with a posterior and medial curvature, and is topped with a little conical nodule composed of cartilage,

known as the corniculate cartilage. The corniculate cartilages, also known as cartilagines cornicu­latae or cartilages of Santorini, are a pair of tiny conical nodules composed of elastic cartilage with a yellowish appearance. These cartilages interact with the tops of the arytenoid cartilages and func­tion to extend them posteriorly and medially. The structures in question are located inside the pos­terior regions of the aryepiglottic folds of mucous membrane, and on occasion, they may be conjoined with the arytenoid cartilages. The cuneiform cartilages, also known as cartilagines cuneiformes or cartilages of Wrisberg, consist of two elongated structures composed of yellow elastic cartilage. These cartilages are situated bilaterally within the aryepiglottic fold, resulting in the formation of small whitish elevations on the mucous membrane’s surface. These elevations are located anteriorly to the arytenoid cartilages.