Thyroid gland, pharynx & esophagus, & larynx & trachea

Endocrine layer: Thyroid and Parathyroid

Respiratory layer: Larynx and Trachea

Alimentary layer: Pharnyx and Esophagus

What is the viscera of the neck superficial to deep? (3) AND what is in each layer?

secretes thyroid hormone (regulation of metabolism) and calcitonin ( Ca concentration in blood)

The endocrine layer has the Thyroid gland that secretes what? (2)

parathyroid hormone (PTH: Ca concentration in blood)

The endocrine layer has the parathyroid gland that secretes what?

1. Conducts air to respiratory tract

2. Directs food into alimentary tract

3. Producing voice

What is the functions of the respiratory layer (3)

1. Conducts air to respiratory tract

2. Directs food into alimentary tract

3. Involved in food propulsion (esophagus)

What are the functions of the Alimentary layer? (3)

anterior portion of neck, deep to sternothyroid and sternohyoid muscles, at the level of C5 – T1 vertebrae

What is the location of the Thyroid gland?

Lobes (R & L)

Isthmus

Pyramidal lobe

Thyroid capsule

What are the parts of the thyroid gland? (3)

anterolateral to larynx and trachea

where are the lobes located in the thyroid gland?

unites lobes over trachea (anterior to 2-4 tracheal rings)

What does the Isthmus unite in the thyroid gland?

projects superiorly towards thyroid cartilage (not always present)

How does the Pyramidal lobe project in the thyroid gland?

fibrous tissue surrounding the thyroid gland

What is the thyroid capsule?

1. Superior thyroid a.: branch of ECA, supply superior portion of the gland

2. Inferior thyroid a.: branch of subclavian a., supply inferior portion of gland

What are the arteries that supply the thyroid gland? (2)

1. Superior and middle thyroid vv.: tributary of IJV

2. Inferior thyroid v.: tributary of brachiocephalic v

What are the veins that drain the thyroid gland? (2)

larnyx

What is the organ of voice production and guards the air passage during swallowing?

in anterior portion of neck, at the level of C3 – C6 vertebral bodies

Where is the location of the Larynx?

superoposterior with laryngopharynx and inferiorly is continuous with trachea

what are the two boundaries of the larynx?

9 cartilages (3 single; 3 paired)

What is the skeleton of the larynx formed by?

1. Thyroid

2. cricoid

3. Epiglottic

What are the three single cartilages of the larynx?

Thyroid (1)

What is the largest laryngeal cartilage?

plates that fuse anteriorly and form the laryngeal prominence (Adam’s apple)

What are the Laminae of the thyroid cartilage? what do they fuse to form?

attach thyroid cartilage superiorly to the hyoid bone

What does the thyroid membrane attach to? (2)

complete ring, narrower anteriorly than posteriorly. Lower border (at the level of C6) marks the inferior limit of the larynx

Where is the cricoid cartilage located? what does it mark the limit of?

attaches cricoid and thyroid cartilages

What does the circothyroid ligament attach to?

forms the conus elasticus and vocals folds (cords)

What does the lateral cricothyroid ligament form? (2)

lateral cricothyroid ligament

CLICINCAL RELIVANCE

cricothyrotomy is conducted by performing an incision through the skin and what membrane to create a patent airway.

elastic cartilage, attached inferiorly to the junction of the laminae of the thyroid cartilage and with a free superior end

What cartilage makes up the epiglottic cartilage? what is attached to?

epiglottic cartilage covered with mucous membrane, located posterior to root of tongue and hyoid bone and anterior to laryngeal inlet (entry to the larynx from the laryngopharynx)

What is the epiglottis covered with? where is it located?

attaches epiglottic cartilage to laminae of thyroid cartilage

What does the Thyroepiglottic ligament attach to?

pyramidal cartilages that articulate with the superior border of the cricoid cartilage

What does the Arytenoid cartilage (2) articulate with ?

superior portion that bears the corniculate cartilage

What is the apex of the arytenoid cartilage (2) bears what?

anterior portion that serves as the posterior attachment for the vocal ligament

The vocal process of the Arytenoid cartilage (2) serves as posterior attachment for what?

extend from the junction of the laminae of thyroid cartilage anteriorly to the vocal process of the arytenoid cartilages posteriorly.

Where do the vocal ligaments of the Arytenoid cartilage (2) extend from?

Vocal ligaments

What ligament makes up the submucosal skeleton of the vocal folds and is the superior free margin of the conus elasticus?

sheet of connective tissue extending between the epiglottic and arytenoid cartilages

What is the Quadrangular membrane? What does it extend between?

inferior free margin of the quadrangular membrane. Makes up the submucosal skeleton of the vestibular fold

What is the Vestibular Ligament? What does it make up?

superior free margin of the quadrangular membrane. Makes up the submucosal skeleton of the ary-epiglottic fold

What does the Ary-epiglottic ligament? what does it make up?

connect to the apex of the arytenoid cartilages

What does the Corniculate cartilage (2) connect?

no directly attached to other cartilages

the cuneiform cartilage has NO (2)

communicates posteriorly with the laryngopharynx

What does the laryngeal inlet communicate posteriorly what?

between laryngeal inlet and vestibular folds

What is the vestibule of the laryngeal cavity between?

on the lateral wall of larynx, at the lower end of vestibule. Inferior free margin of quadrangular membrane

Where are the vestibular folds located and its the inferior free margin of what?

recess or depression extending laterally between vestibular and vocal folds

What is the ventricle of the laryngeal cavity? what is it located between?

sharp-edge folds of mucous membrane that projects medially into the laryngeal cavity

what are the Vocal folds of the laryngeal cavity?

between vocal folds and inferior border of cricoid cartilage. It’s continuous with trachea

what is the Infraglottic cavity between? what is it continuous with?

comprised by the vocals folds and rima glottidis

What is the Glottis comprised by?

space between vestibular folds

what is the Rima Vestibuli?

aperture between vocals folds

What is the Rima Glottidis

lateral portion of the cricothryoid ligament. Its free superior margin forms the vocal ligament

What is the conus elasticus? Its free superior margin forms what?

1. Provide protection and adjustment of larynx and vocal cord during phonation and respiration

2. Involved in sound production and opening and closing the airway during respiration

3. Move laryngeal components, altering the length and tension of the vocal folds and shape of the rima glottidis

what are the intrinsic muscles of the larynx functions? (3)

recurrent laryngeal nerve (CN X), except cricothyroid muscle innervated by the external laryngeal nerve (CN X)

ALL intrinsic muscles are innervated by the _______ nerve expet the ______ muscle which is innervate by the __________ nerve

work on the larynx as a whole. Move the larynx as an entire organ, while the intrinsic muscles make adjustments

What do the extrinsic muscles of the larynx V.S the intrinsic muscles do?

1. Infrahyoid muscles: depressors of hyoid and larynx

2. Suprahyoid muscles: elevators of the hyoid and larynx

What are the Extrinsic muscles of the Larynx? (2) What is their action?

1. Superior and inferior laryngeal arteries: branches of the superior and inferior thyroid aa. Same aa. supplying the thyroid supply the larynx

what are the arteries assocated to the larynx? (2)

Superior and inferior laryngeal veins: drain into superior thyroid v.

What veins supply the Larynx?

CN X

Persistent hoarse voice is an indication that someone may have Which nerve problems

motor to cricothyroid (intrinsic muscle of larynx)

the superior laryngeal nerve External provides motor innervation to what muscle?

sensory and parasympathetic to inside of larynx

The superior laryngeal nerve Internal provides and innervates what?

motor to all other intrinsic muscles of larynx. Goes inferiorly and curves below the subclavian on right and below the aortic arch on left going between the trachea and esophagus.

The recurrent laryngeal nerve provides motor innervation to what? What is its course L & R?

supported by incomplete cartilagenous rings (tracheal cartilages)

The trachea is a fibrocartilagenous ring supported by what?

extends from the larynx (at the level C6) inferiorly into the thorax (at the level T4 or sternal angle), where it divides into R & L bronchi

What is the location of the trachea? where does it divide?

transports air to and from lungs

what if the function of the trachea?

Pharynx

What is the superior expanded part of the alimentary system?

extend from cranial base to inferior border of the cricoid cartilage (at the level of C6), where is continuous with the esophagus

what is the location of the pharynx?

1. Nasopharynx

2. Oropharynx

3. Laryngopharynx

What are the three divisions of the Pharynx?

posterior to nose and superior to soft palate

Where is the location of the Nasopharynx?

posterior to mouth, and below soft palate

Where is the location of the Oropharynx?

posterior to the larynx

What is the location of the Laryngopharynx?

Posterior extension of nasal cavities, involved in respiration

The Nasopharynx is a posterior extension of what? what is it involved in?

lymphoid tissue masses on the superior and posterior aspect of the nasopharynx.

what are the pharyngeal tonsils of the nasopharynx?

Pharyngeal tonsils

CLINCIAL RELIVANCE what tonsils are commonly called adenoids and many times removed (adenoidectomy) when swollen, which could block airflow in the nasal passage

on lateral wall of nasopharynx

where is the Opening of pharyngotympanic tube

rim of tissue around opening pharyngotympanic tube, formed by the cartilage of the auditory tube as it pokes the lateral wall of the nasopharynx

where is the Torus of the pharyngotympanic tube (torus tubarius) located? what is it formed by?

fold of tissue that extends down from torus of the pharyngotympanic tube. It is mucus membrane covering the salpingopharyngeus muscle

What is the Salpingopharyngeal fold what does it cover?

lateral and posterior projection of the pharynx, posterior to the salpingopharyngeal fold

what is the Pharyngeal recess located?

S: soft palate

I: root of tongue

L: palatoglossal & palatopharyngeal arches

What are the boudaries of the Oropharynx

extends inferiorly from the soft palate to the superior border of the epiglottis, and is involved in digestion

where is the location of the oropharynx

mass of lymphoid tissue on each side of oropharynx, between the palatine arches (palatoglossal & palatopharyngeal)

What are the palatine tonsils in the Oropharynx? What are they between?

Palatine tonsils

CLINCIAL RELIVANCE

tonsillectomy involves the removal of what tonsil, when inflamed, and many times is conducted in combination with an adenoidectomy. The ICA lies posterolateral to the tonsillar bed, and a mistake during tonsillectomy could be disastrous

posterior to the larynx, extends from the superior border of the epiglottis to the inferior border of the cricoid cartilage, where it becomes continuous inferiorly with the esophagus

what is the location of the Laryngopharynx?

communicates the laryngopharynx posteriorly with the larynx anteriorly

What does the laryngeal inlet communicate with in the Laryngopharynx?

small depression of the laryngopharynx on either side of pharyngeal inlet.

What is the Piriform fossa (recess)

Pharyngeal constrictors: Superior, Middle, Inferior

Contraction: involuntary and sequential from superior to inferior end of the pharynx

What are the external circular layer of the pharyngeal muscles? (3) What are their fuctions?

Palatopharyngeous

Salpingopharyngeous

Stylopharyngeous

What are the internal longitudinal layer muscles of the Pharyngeal muscles? (3)

strong internal fascial lining of the pharyngeal constrictor muscles

what is the Pharyngobasilar fascia and what does it line?

thin external fascial lining of the pharyngeal constrictor muscles

What is the Buccopharyngeal fascia and what does it line?

on lateral wall of pharynx

where are the Pharyngeal plexus of nerves located

CN X, CN IX

superior cervical ganglion

what are the Pharyngeal branches of what nerves?

Sympathetic fibers from what ganglion?

1. Ascending pharyngeal

2. Superior thyroid a.

3. Inferior thyroid a.

What are the arteries associated with the pharyngeal layer? (3)

1. Pharyngeal venous plexus

What are the veins that drain the pharyngeal layer? (1)

Muscular tube connecting the pharynx to the stomach, posterior to the trachea in cervical region

What is the esophagus and what does it connect to?

Extends from the laryngopharynx superiorly (at the level of C6 and inferior border of cricoid cartilage) to the stomach in the abdomen

What does the esophagus extend from?

Superior 1/3rd: striated

Middle 1/3rd: striated and smooth

Inferior 1/3rd: smooth

What is the muscular distribution of the esophagus? (3)

part of the voluntary upper 1/3rd

What is the cervical esophagus?

cricopharyngeal part of the inferior pharyngeal constrictor muscle

what is the superior esophageal sphincter?