B26 - Larynx, blood supply and innervation Flashcards
1
Q
Role of larynx
A
- Protection of lower respiratory passages from getting filled with liquids or food
- Phonation - voice formation
2
Q
What does the larynx connect?
A
Larynx forms connection between pharynx and the tracheobronchial tree
3
Q
Location of larynx
A
- Larynx lies below pharynx
- Behind the mouth
- Suspended from the cranial base of the hyoid apparatus
- Because of its connection with the tongue and hyoid bone, the larynx shift its position during swallowing.
4
Q
Cartligaes
List the cartilages of the larynx
A
- Epiglottis
- Cart. thyroidea
- Cart. cricoidea
- Cart. arythnoidea
5
Q
Cartilages
Epiglottis
A
- Facies lingualis
- Facies laryngea
- Basis (Attached to cart. thyroidea)
- Apex (Free rostral)
- Petiolus epiglottidis
-
Cartilago epiglottica
- Processus cuneiformis (eq) (Projects in the vestibular fold)
- Lig. thyreoepiglotticum (Attaches epiglottis base → cart. thyroidea)
- Lig. hyoepiglotticum (From basihyoideum and keratohyoideum → epiglotttis)
- Unpaired
- Most rostral part of larynx
- Elastic cartilage
6
Q
Cartilages
Cart. thyroidea
A
- Lamina dextra et sinistra (Plates joined ventrally to form the thyroid cartilage)
- Incisura thyreoidea rostralis (Ru)
- Incisura thyreoidea caudalis
- Linea obliqua (On the lateral surface of the lamina, for muscle attachment)
- Cornu rostrale (Ø su) (Articulates with the os hyoideum)
- Cornu caudale (Articulates with the cart. cricoidea)
-
Fissura thyreoidea (Between the rostral horn and the lamina)
- Foramen thyreoideum (In the caudal end of the thyroid fissure)
- Articulatio thyreohyoidea
- Membrana thyreohyoidea (From the rostral border of the thyroid lamina to the basihyoid and thyrohyoid bones)
- Unpaired
- Foramen tyrohyoideum transmits sensory fibers of n. laryngeus cranialis for innervation of mucous membrane
7
Q
Cartilages
Cart. cricoidea
A
- Arcus cartilaginis cricoideae (Narrow ventral part)
-
Lamina cartilaginis cricoideae (Broad dorsal part)
- Crista mediana
- Articulatio cricothyreoidea
- Lig. cricothyreoideum (From cart. cricoidea → laminae thyroidea)
- Lig. cricotracheale (Membrane between the cricoid cartilage and the first tracheal ring)
- Unpaired
8
Q
Cartilages
Cart. arythnoidea
A
- Proc.vocalis (Ventral projection, attachment for vocal ligament)
- Proc. muscularis (At the caudal end of the crista arcurata)
- Proc. corniculatus (ø fe)
- Proc. cuneiformis (ca) (Attached to the apex of the arytenoid. Supports the plica aryepiglottica and the plica vestibuli)
- Cartilago interarytenoidea (ca, su) (Dorsal to lig. arythnoideum transversum)
- Cartilago sesamoidea (ca) (Lies across the dorsal surface of the cart. arythnoidea, caudal to the proc. corniculatus)
- Articulatio cricoarytenoidea
- Lig. cricoarytenoideum (From the cricoid lamina → base of cart. arythnoidea)
- Paired
- Opens and close the glottis
9
Q
Articulations
List the articulations in larynx
A
-
Hyoepiglottic connection
- Formed by lig. hyoepiglotticum
- Base of epiglottis → hyoid bone
-
Thyroepiglottic connection
- Formed by lig. thyroepiglotticum
- Base of epiglottis → cart. thyroidea
-
Thyroid cartilage and thyrohyoid connectio
-
Membrana thyrohyoidea
- Extends from cart. thyroidea → basihyoid & thyrohyoid
-
Membrana thyrohyoidea
-
Interarytenoid connection
-
Formed by lig. arytenoideum transversum
- Connects the dosocaudal angles of the two cartilages
-
Formed by lig. arytenoideum transversum
-
Cricoarythnoid connection
- Regulates the size of the glottic opening
-
Cricothyroid connection
- Allows rotation around a transverse axis
-
Cricotracheal connection
- Formed by lig. cricotracheale
Articulation:
- Lig. hyoepiglotticum
- Lig. thyroepiglotticum
- Membrana thyroidea
- Lig. arythnoideum transversus (between 2 arythnoid cartilages)
- Lig. cricoarythnoideum
- Lig. cricothyroideum
- Lig. circotracheale
10
Q
List the muscles of the larynx
A
- Extrinsic musculature:
- M. hyopharyngeus
- M. thyropharyngeus
- M. thyrohyoideus
- M. sternothyroideus
- M. sternohyoideus
- Action: move the larynx during swallowing
- Intrinsic muscles:
-
M. cricothyroideus
- Cricoid arch → thyroid cartilage
- Tense vocal cords
-
M. cricoarytenoideus dorsalis
- Cricoid lamina → proc. muscularis of cart. arythonidea
- Widens the glottis
-
M. cricoarytenoideus lateralis
- Cricoid arch → proc. muscularis of cart. arythonidea
- Narrows glottis
-
M. thyroarytnenoideus
- Cranial part of laryngeal floor (cart. thyroidea) → proc. muscularis of cart. arythonidea**
- Ca, eq: divided into m. ventricularis (rostral) and m. vocalis (dorsal)
- M. hyoepiglottis
- M. vocalis
- M. ventricularis
-
M. cricothyroideus
11
Q
Laryngeal cavity
A
-
Ventriculus laryngis:
- Car, sus, eq: diverticulum of the laryngeal mucosa in the lateral wall
- Fe, ru: Ø ventricles, but shallow depressions
-
Plica vestibularis encloses:
- Lig. vestibularis
- M. ventricularis
- Proc. cueniformis of cart. arythnoidea
-
Plica vocalis contains:
- Lig. vocalis
- M. vocalis
- Bounded laterally by: cart. thyroidea
- Bounded medially by: cart. arythnoidea
-
Plica aryepiglottica:
- On each side of the entrance of the larynx
- Arises from the lateral margins of the epiglottis
- Encloses the entrance to the laryngeal cavity:
- Plica
- Epiglottis
- Proc. corniculatus
-
Recessus piriformis:
- Two channels of the floor of laryngopharynx
- Bounded medially by:
- Epiglottis
- Plica aryepiglottica
- Bonuded laterally by:
- Thyroid lamina
- Hyoid bones
12
Q
Cavum laryngis
The cavity of the larynx
A
- Divided into 3 sections
-
Vestibulum laryngis:
- Extends from aditus laryngis → glottis
-
Auditus laryngis:
- Rostral part of the wall of the entrance: epiglottis
- Lateral part: pila aryepiglottica
- Caudal part: proc. corniculata of cart. arytenoidea
-
Glottis:
- Vocal apparatus of the larynx
- Consists of:
- Vocal folds
- Cart. arytenodiea
- Rima glottis (glottic cleft)
-
Cavum infraglotticum:
- Leads to lumen of trachea
- Within cart. cricoidea
13
Q
Cavum laryngis
Structures to mention in cavum laryngis
A
- Aditus laryngis (Entrance to the larynx, bounded epiglottis, plica aryepiglotticae, and tubercula corniculata)
- Plica aryepiglottica (From epiglottis, to ….)
- Vestibulum laryngis (Between aditus → plica vocalis)
- Plica vestibularis (Ø su, Ru)
- Rima vestibuli (Vestibular cleft, between right and left vestibular folds)
- Ventriculus laryngis (Ø Ru) (Ca, eq: between plica vestibularis → plica vocalis)
- Glottis (Vocal apparatus of the larynx. Consists of vocal folds, cart. arytenoidea and rima glottidis)
- Plica vocalis
- Rima glottidis (Cleft of glottis. Between plica vocalis → cart. arytenoidea)
- Pars intermembranacea (Between plica vocalis)
- Pars intercartilaginea (Between the mucosa-covered arytenoid cartilages)
- Cavum infraglotticum (Caudal to glottis)
- Lig. vestibulare (Ø Ru, fe) (Ca: cart. thyroidea → proc. corniculatus, eq: proc. cueniformis → cart. arytenoidea)
- Lig. vocale (From cart thyroidea and lig. cricothyroideum → proc. vocalis)
14
Q
Blood supply of the larynx
A
-
A. carotis communis
-
A. thyroidea cranialis
-
A. laryngea cranialis
- R. laryngeus caudalis
- R. cricothyroideus
- Ca: r. laryngeus (→ larynx through fissura thyroidea)
-
A. laryngea cranialis
- A. thyroidea caudalis
-
A. thyroidea cranialis
15
Q
Innervation of the larynx
A
- From n. vagus:
-
N. laryngeus cranialis (→ mucous membrane of larynx)
- R. externa (→ m. cricothyroideus)
- R. interna (→ mucosa)
-
N. laryngeus caudalis = n. laryngeus recurrens (→ muscles of larynx, ø m. cricothyroideus)
- N. laryngeus recurrens → ansa subclavia → n. laryngeus recurrens → n. laryngeus caudalis
-
N. laryngeus cranialis (→ mucous membrane of larynx)
Ansa subclavia around a. subclavia sinistra
