SAQ 6 Flashcards
The Larynx
- specially modified for vocalization.
- It is situated anteriorly in the neck, below the hyoid bone and the tongue.
- It has a marked anterior projection, the laryngeal prominence (Adam’s apple).
- Related anteriorly to it is the skin and fasciae and laterally, the thin strap muscles of the neck, the thyroid gland, the great vessels of the neck, and the vagus nerves. posteriorly related are the vertebral column and the prevertebral muscles separated from them by the laryngopharynx.
The Larynx Function:
• Function:
– Organ of vocalization or phonation
– Air passage
– Sphincter
The Larynx Extent:
• Extent:
– Between the root of the tongue and the trachea
– In the adult, it extends between C3-C6.
The Larynx Communications:
• Communications:
– Superiorly with the laryngopharynx through the
laryngeal inlet
– Inferiorly with the trachea
Laryngeal Cartilages
- paired
- unpaired
two types: hyaline and elastic cartilages of which there are 2 groups: – Unpaired: thyroid, cricoid, & epiglottis – Paired: arytenoids, corniculates, & cuneiforms
Laryngeal membranes & ligaments
- extrensic
- intrinsic
– Extrinsic – attach structures inside the larynx to structures outside the larynx – Intrinsic – attach structures of the larynx together
The thyroid cartilage
The thyroid cartilage is a hyaline cartilage
located under the hyoid bone. It is made up of two laminae meeting in the midline. The
posterior border extends upward to form the
superior horn, and downward to form the
inferior horn.
The thyroid cartilage Landmarks:
Landmarks: – Thyroid notch – Laryngeal prominence (where 2 laminae meet) – Superior & inferior thyroid tubercles – Oblique line
The thyroid cartilage Articulations
Articulations: Cricothyroid – between the
inferior cornu of the thyoid cartilage and the
lateral side of the cricoid cartilage
The thyroid cartilage Attachments:
Attachments:
– To cricoid by the cricothyroid ligament
– To epiglottis by the thyroepiglottic ligament
– To vocal process of arytenoid by vocal ligament
– To hyoid bone by thyrohyoid membrane
Cricoid Cartilage
The cricoid is a hyaline cartilage shaped like a signet ring; it consists of an anterior arch and a posterior quadrangular lamina.
Cricoid Cartilage Articulations
• Articulations:
– Cricothyroid
– Cricoarytenoid
Cricoid Cartilage Attachments
• Attachments: – To thyroid by cricothyroid ligament – To trachea by the cricotracheal ligament
Arytenoid Cartilages
These are a pair of cartilages located on the lateral side of the superior border of cricoid
lamina. Each is a 3-sided pyramid with 3 surfaces, a base, an apex, and 2 processes:
vocal & muscular.
Arytenoid Cartilages Articulations:
Articulations:
– With cricoid lamina
– With corniculate cartilage
Arytenoid Cartilages Attachments:
Attachments: – To thyoid cartilage by the vocal ligament – To epiglottis by the quadrangular membrane
Epiglottic Cartilage
This is a leaf-like elastic cartilage which projects upward behind the tongue and hyoid bone. Its stalk is attached to the back of the thyroid cartilage. • During deglutition, it bends back over the laryngeal inlet. In humans, it is somewhat degenerate in function and is not essential to swallowing.
Epiglottic Cartilage Attachments:
Attachments: – To thyroid – To hyoid – Arytenoids – To the tongue
Smaller Cartilages Corniculate
Corniculate cartilages – are 2 small conical nodules of yellow elastic cartilage. They lie on the apices of the arytenoid cartilages
and serve to prolong them backward and medialward. They are enclosed within the posterior parts of the aryepiglottic folds.
Smaller Cartilages Cuneiform
Cuneiform cartilages – also formed of yellow elastic cartilage, are small, rod-like bodies in the aryepiglottic fold anterior to the
corniculate cartilages.
Smaller Cartilages Tritiate
Tritiate (triticeal) cartilage – are 2 small nodules of elastic cartilage situated one on either side above the larynx within the posterior free edge of the thyrohyoid
*Find the tritiate in between the tip of the greater horn of the hyoid bone, and the tip of the superior horn of the thyroid Cartilage.membrane
Membranes & Ligaments
*Extrinsic membrane
Extrinsic
– Thyrohyoid membrane
– Cricotracheal ligament
– Hyoepiglottic ligament
Membranes & Ligaments
*Intrinsic membrane
Intrinsic
– Quadrangular membrane: between the epiglottis and arytenoid cartilages. Its inferior border forms the vestibular ligaments.
*Quadrangular membrane is covered by mucous membrane.
Superior border of the quadrangular membrane is called the Aryepiglottic fold.
Inferior border is the vestibular fold and ligament.
Membranes & Ligaments
*Intrinsic ligament
Intrinsic
– Cricothyroid ligament
• Median portion
• Lateral portion – its upper edge is the
vocal ligament; together the vocal ligament and the lateral cricothyroid ligament form the
conus elasticus
– Thyroepiglottic ligament
Boundaries & Subdivisions bounded by:
bounded:
– Anteriorly by the epiglottis
– Laterally by the aryepiglottic folds
– Posteriorly by the mucous membrane between the arytenoid cartilages
Boundaries & Subdivisions Parts
• Parts:
– Vestibule – space between the inlet and the vestibular folds
– Ventricle – space between the vestibular folds and the vocal folds; extends anteriorly to form the saccule; the saccule contains
mucous glands to lubricate the vocal folds
– Infraglottic cavity – space between the vocal folds and the inferior border of the cricoid cartilage Rima vestibuli: space between the right & left vestibular folds
Rima glottidis: space between the right & left vocal folds
Extrinsic Laryngeal Muscles
These are muscles which elevate or depress the larynx either directly or through its attachment to the hyoid bone through the
thyrohyoid membrane and hyoepiglottic ligament.
Elevators of the larynx:
Elevators of the larynx: – Digastric – Stylohyoid – Mylohyoid – Geniohyoid – Stylopharyngeus – Salpingopharyngeus – Palatopharyngeus
Depressors of the larynx:
Depressors of the larynx: – Sternothyroid – Sternohyoid – Omohyoid -*Stylopharyngeus
Cricothyroid
Chief tensor of vocal ligament
Posterior cricoarytenoid
Abductor of vocal folds
Transverse & oblique arytenoids
Close rima glottidis
Lateral cricoarytenoid
Adducts vocal folds
Thyroarytenoid
Slackens vocal folds and closes rima glottidis
Vocalis
Adjusts tension of vocal ligament
Larynx Nerve Supply sensory
• Sensory Supply
– Internal laryngeal nerve: is a branch of the superior laryngeal nerve of the vagus. It supplies the laryngeal mucosa down to
the level of the vocal folds
– Recurrent laryngeal nerve: supplies the laryngeal mucosa below the level of the vocal folds
Larynx Nerve Supply motor
Motor Supply
– External laryngeal nerve: is a branch of the superior laryngeal nerve of the vagus. It supplies the cricothyroid muscle.
– Recurrent laryngeal nerve: supplies all the intrinsic laryngeal muscles, except the cricothyroid
The Internal Laryngeal Nerve is accompanied by the _________
Superior Laryngeal Artery
________Supplyies cricothyroid muscle.
- Superior thyroid artery gives off the Cricothyroid Branch, which accompanies__________
-external laryngeal nerve
ARTERIAL SUPPLY to larynx
ARTERIAL SUPPLY
– Superior laryngeal artery, a branch of the superior thyroid artery. It supplies the upper
half of the larynx.
– Inferior laryngeal artery, a branch of the inferior thyroid artery. It supplies the lower
half of the larynx.
VENOUS DRAINAGE to larynx
VENOUS DRAINAGE
– The veins accompanying the Superior laryngeal artery, drains into superior thyroid
vein which drains into internal jugular vein.
– The veins accompanying the Inferior laryngeal artery drain into the inferior thyroid vein, which drains into the brachiocephalic vein.
– The veins accompanying the Superior laryngeal artery, drains into superior thyroid
vein which drains into internal jugular vein.
– The veins accompanying the Inferior laryngeal artery drain into the inferior thyroid vein, which drains into the brachiocephalic vein.
Laryngoscopy:
Laryngoscopy: clinical examination of patient’s larynx directly (laryngeal endoscopy) or indirectly through mirror
reflection clinical examination of patient’s larynx directly (laryngeal endoscopy) or indirectly through mirror reflection
*has to pull the tongue outward for it to not contract.
Laryngotomy:
Laryngotomy: surgical procedure to introduce air into lower larynx and trachea, e.g., in case of laryngeal edema or impacted foreign body.
Laryngectomy
Laryngectomy: surgical resection of the larynx, e.g., malignant laryngeal tumor or
tumors contiguous to the larynx.: surgical
resection of the larynx, e.g., malignant laryngeal tumor or tumors contiguous to the
larynx.
The Pharynx
*extends from base of skull to soft palate
The pharynx is the common chamber of the respiratory and digestive tracts.
• It is located behind the nasal and oral cavities.
• It is continued below into the separated larynx and esophagus.
• The pharynx is somewhat funnelshaped
Subdivisions of pharynx
Subdivisions
•NASOPHARYNX:
- OROPHARYNX:
- LARYNGOPHARYNX:
•NASOPHARYNX:
COMMUNICATES WITH NASAL CAVITY
•OROPHARYNX:
COMMUNICATES WITH ORAL CAVITY
•LARYNGOPHARYNX:
COMMUNICATES WITH LARYNGEAL CAVITY
Nasopharynx
- The Nasopharynx is entirely respiratory. Its wall are relatively rigid, and its chambers cannot be obliterated.
- EXTENT: From base of the skull to the level of the soft palate.
Nasopharynx boundaries
- ROOF: Supported by body of the sphenoid and basilar part of occipital bone. It contains the pharyngeal tonsil.
- FLOOR: Sloping upper surface of soft palate. The pharyngeal isthmus is the opening in the floor between the free edge of soft palate and posterior pharyngeal wall.
- ANTERIOR WALL: Formed by posterior nasal apertures.
- POSTERIOR WALL: Supported by the anterior atlantic arch.
- LATERAL WALL: Has pharyngeal opening of auditory tube, tubal elevation (torus tubarius), salpingo-pharyngeal fold and pharyngeal recess
Oropharynx
Oropharynx
• The Oropharynx represents the digestive
entrance of the chamber.
• EXTENT: From soft palate to upper border of epiglottis.
Oropharynx boundaries
• ROOF: Under surface of soft palate and the
pharyngeal isthmus.
• FLOOR: Posterior one third of the tongue and the interval between the tongue and the
anterior surface of the epiglottis. It contains
the lingual tonsil.
• ANTERIOR WALL: Opens into the mouth
through the oropharyngeal isthmus.
• POSTERIOR WALL: Supported by the body of the C2 vertebra, upper part of the body of C3 and the IVD in between.
• LATERAL WALL: Has the palatoglossal and
palatopharyngeal folds. Between these folds
rest the palatine tonsil.
- ## All muscles ending is glossus will be supplied by hypoglossus except ______
except
palatoglossus muscle is supplied by the vagus.
All muscles ending is pharyngeus are supplied by vagus, except ________
the stylopharyngeus which is supplied by the glossopharyngeal nerve.
The Laryngopharynx
• The Laryngopharynx lies behind the
laryngeal inlet and posterior wall of the
larynx.
• EXTENT: From upper border of epiglottis to
lower border of cricoid cartilage.
The Laryngopharynx boundaries
• SUPERIORLY: It communicates with the
lumen of the oral pharynx.
• INFERIORLY: It communicates with the
lumen of the esophagus.
• ANTERIOR WALL: Inlet of the larynx and the mucous membrane covering the posterior aspect of the larynx. Piriform fossa is a groove in the mucous membrane on each side of laryngeal inlet.
• POSTERIOR WALL: Supported by the lower
part of the body of C3 and bodies of C4- C6
and the IVDs in between. (constrictor muscles of the pharynx)
• LATERAL WALL: Supported by the thyroid
cartilage and thyrohyoid membrane.
piriform recess, allows for fluid to run through, another place where a fish bone can get stuck. and the _______ nerve is ______
Internal laryngeal nerve is deep inside.
Structure of the Pharyngeal Wall
The pharyngeal wall is lined by a mucous
membrane continuous with all the
chambers with which it communicates.
• The submucosa is a strong fibrous sheet,
known as the pharyngobasilar fascia. This
fascia blends with the periosteum of the
base of the skull in front of the pharyngeal
tubercle. It defines the limits of the
pharyngeal wall in its upper portion.
• The muscular coat of the pharynx lies
external to the pharyngobasilar fascia, the
muscles are in turn covered externally by
the buccopharyngeal fascia.
• The pharynx is separated posteriorly from
the vertebral column and the prevertebral
muscle and fascia by the loose areolar
connective tissue of the retropharyngeal
space (space of Stiles). This loose tissue
permits the elevation and depression of
the pharynx during deglutition.
retropharyngeal space -
sig. whiplash injury, blood will accumulate in space.
swallowing AKA
Deglutition is swallowing.
Muscles of the Pharynx external layer
Superior constrictor
Middle constrictor
Inferior constrictor
ALL Constricts walls of pharynx during swallowing
Muscles of the Pharynx internal layer
Palatopharyngeus
Salpingopharyngeus
Stylopharyngeus
All Elevate (shorten & widen) pharynx during swallowing& speaking
Superior constrictor
nerve-Pharyngeal branch of vagus and pharyngeal
plexus
Middle and inferior constrictor
nerve-Pharyngeal branch of vagus and pharyngeal
plexus, plus branches of external and recurrent laryngeal nerves
Palatopharyngeus and Salpingopharyngeus
nerve- Pharyngeal branch of vagus and pharyngeal plexus
Stylopharyngeus
nerve- Glossopharyngeal nerve
The Tonsillar (Waldeyer’s) Ring
PHARYNGEAL TONSIL
• PHARYNGEAL TONSIL – is an aggregate of
lymphoid tissue located under the
mucous membrane lining the roof of the
nasal pharynx.
• TUBAL TONSIL
• TUBAL TONSIL – lymphoid tissue located
at the opening of the auditory tube
• PALATINE TONSILS
• PALATINE TONSILS – are two aggregates
of lymphoid tissue located in the lateral walls of the oral pharynx. Anteriorly it is bounded by the palatoglossal arch. Posteriorly it is bound by the palatopharyngeal arch, and occupy the tonsillar sinus in between.
• LINGUAL TONSIL
• LINGUAL TONSIL – is an aggregate of
lymphoid tissue located in the floor of the
oral pharynx under the mucous membrane covering the root of the tongue.
What makes the tonsilar ring?
gives opening to what?
pharyngeal, tubal tonsil, palatine and lingual tonsils.
-oropharynx & nasopharynx.
- mucosal fold found anterior to palatine tonsil is the ______ fold/arc.
- The _______ fold/arc is behind that.
- palatoglossal
- palatopharyngeal
Nerve Supply to pharynx:
Nerve Supply
• PHARYNGEAL PLEXUS (PP) – is a plexus of
nerves on side and back of the pharynx. The plexus is formed by contributions from the glossopharyngeal (IX), vagus (X) and sympathetic nerves.
Nerve Supply to pharynx: sensory
• SENSORY NERVE SUPPLY - to the mucous membrane of the pharynx: – Nasopharynx by maxillary nerve. – Oropharynx by glossopharyngeal nerve. – Area around the entrance into the larynx by internal laryngeal branch of the vagus.
supplies mucosa of the epiglottis
Blood Supply to pharynx: arterial supply
ARTERIAL SUPPLY – is derived from branches of:
– Ascending pharyngeal artery (branch of external carotid artery).
– Ascending palatine and tonsillar arteries (branches of facial artery).
– Greater palatine artery (branch of maxillary artery).
– Dorsal lingual branches of lingual artery.
Blood Supply to pharynx: venous drainage
VENOUS DRAINAGE – The veins drain into the internal jugular vein through the pharyngeal venous plexus.
What three muscles attach on to the oblique line of the thyroid cartilage?
Thyrohyoid, sternothyroid and inferior constrictor muscle
