Pharynx and Larynx Flashcards
Oropharynx
extends from the level of the palatoglossal arches to the caudal border of the soft palate and the base of the epiglottis at the caudal end of the root of the tongue; dorsal and ventral boundaries are the soft palate and the root of the tongue; lateral wall contains the palatine tonsil and the tonsillar fossa
Palatine tonsil
elongated and located caudal to the palatoglossal arch; covered by the semilunar fold
Semilunar fold
medial wall of the tonsillar fossa; covers the palatine tonsil
Opening of the nasolacrimal duct
on the floor of the rostrolateral end of the ventral meatus. on the ventral aspect of the alar fold; comes from the lacrimal sac at the medial commissure of the eye
Nasopharynx
extends from the choanae to the junction of the palatopharyngeal arches at the caudal border of the soft palate
Palatopharyngeal arch
extends caudally on each side from the caudal border of the soft palate to the dorsolateral wall of the nasopharynx; fold of mucosa that covers the palatopharyngeus muscle
Opening of the auditory tube
oblique, slit-like opening in the nasopharynx; on the lateral wall, dorsal to the middle of the soft palate
Pharyngoesophageal limen
annular constriction at the level of the cricoid cartilage; caudal boundary of the the laryngopharynx from the esophagus
Laryngopharynx
dorsal to the larynx; extends from the palatopharyngeal arches to the beginning of the esophagus (pharyngealesophageal limen)
Cricopharyngeus muscle
caudally its fibers blend with the esophagus
origin: lateral surface of the cricoid cartilage
insertion: median dorsal raphe of the laryngopharynx;
action: aid directly in swallowing
innervation: Glossopharyngeal and vagus nn.
Thyropharyngeus muscle
rostral to the cricopharyngeus and caudal to the hyopharyngeus
origin: lateral side of the thyroid lamina
insertion: median dorsal raphe of the pharynx
action: aid directly in swallowing
innervation: Glossopharyngeal and vagus nn.
Hyopharyngeus muscle
origin: 2 parts- lateral surface of the thyrohyoid bone, lateral surface of the ceratohyoid bone
insertion: median dorsal raphe of the pharynx
action: aid directly in swallowing
innervation: pharyngeal branches of the Glossopharyngeal nerve (CN IX) and Vagus nerve (CN X)
Epiglottic cartilage
lies at the entrance to the larynx; lingual surface is attached to the basihyoid bone and faces the oropharynx; apex lies just dorsal to the edge of the soft palate; lateral margin is attached by mucosa to the cuneiform process of the arytenoid to form the aryepiglottic fold
Aryepiglottic fold
attachment of the lateral epiglottic cartilage to the cuneiform process of the arytenoid cartilage; mucosal fold
Thyroid cartilage
forms a deep trough, open dorsally, cartilage of the larynx
Rostral cornu
articulates with the thyrohyoid bone, process off the thyroid cartilage
Caudal cornu
articulates with the caudal aspect of the cricoid cartilage; ventrally, the caudal border is notched by the caudal thyroid incisure; process off the thyroid cartilage
Caudal thyroid incisure
notch in the caudal border of the ventral part of the thyroid cartilage, caudal cornu
Cricothyroid ligament
attaches the caudal border of the thyroid cartilage to the ventral arch of the cricoid cartilage
Cricoid cartilage
forms a complete ring that lies partially within the trough of the thyroid cartilage; wide dorsal plate (lamina) and a narrow ventral arch; near the caudal border at the junction of the lamina and the arch, there is a lateral facet for articulation with the caudal cornu of the thyroid cartilage; on the cranial border of the lamina, there is a prominent pair of lateral facets for articulation with the arytenoid cartilage
Arytenoid cartilage
paired, irregular in shape, located in a sagittal plane; each articulates medially with a facet on the rostral border of the cricoid lamina and has 4 processes
Muscular process
lateral
Vocal process
ventrally directed
Corniculate process
dorsal
Cuneiform process
rostral to corniculate process
Vestibular fold
extends from the thyroid cartilage ventrally to the ventral portion of the cuneiform process and forms the rostral boundary of the laryngeal ventricle
Laryngeal ventrible
diverticulum of the laryngeal mucosa bounded laterally by the thyroid cartilage and medially by the arytenoid cartilage; opens into the larynx between the vestibular fold rostrally and vocal fold caudally
Vocal fold
attached between the vocal process of the arytenoid and the midventral part of the thyroid cartilage
Glottis
consists of vocal folds, the vocal processes of the artenoid cartilages
Rima glottidis
narrow passageway through the glottis; size and shape can be altered by muscular activity
Cricothyroid muscle
lies ventral to the insertion of the sternothyroideus muscle and passes from the cricoid cartilage to the thyroid lamina
action: tenses the vocal fold indirectly, draws ventral parts of the cricoid and thyroid cartilages together
innervation: cranial laryngeal nerve
Dorsal cricoarytenoid muscle (cricoarytenoideus dorsalis)
origin: dorsolateral surface of the cricoid cartilage
insertion: muscular process on the lateral surface of the arytenoid cartilage
action: rotates the arytenoid so that the vocal process moves laterally, opening the glottis; only muscle with that primary function
innervation: caudal laryngeal nerve
Lateral cricoarytenoid muscle (cricoarytenoideus lateralis)
origin: lateral surface of the cricoid cartilage
insertion: arytenoid cartilage between the cricoarytenoideus dorsalis and the vocalis
action: close the glottis by pulling the muscular process ventrally and thus moving the vocal process medially
innervation: caudal laryngeal nerve
Thyroarytenoid muscle
gives rise to the vocalis muscle medially and ventricularis muscle rostrally
origin: internal midline of the thyroid cartilage and inserts on the arytenoid cartilage
action: relax vocal fold, constrict glottis
innervation: caudal laryngeal nerve
Vocalis muscle
medial division of the thyroarytenoid muscle
origin: internal midline of the thyroid cartilage
insertion: vocal process of the arytenoid cartilage
action: Relaxes vocal fold
innervation: Caudal laryngeal n.
