dr. hassan shaibah و ما أوتيتم من العلم إلا قليلا
TRANSCRIPT
Dr. Hassan Shaibah
قليال إال العلم من أوتيتم ما و
The pharynxa musculofascial
half-cylinder that links oral & nasal cavities in the head to the larynx & esophagus in the neck.
The pharyngeal cavity is a common pathway for air and 'food'.
pharynx is subdivided into three regions,
1.nasopharynx,2.oropharynx,3.laryngopharynx
Nasopharynx is behind the choanae of the
nasal cavities and above the level of the soft palate.
There is a large collection of lymphoid tissue (the pharyngeal tonsil) in the mucosa covering the roof of the nasopharynx.
Enlargement of this tonsil, known then as adenoids, can occlude the nasopharynx so that breathing is only possible through the oral cavity
in the pharynx that the air and food pathways
the soft palate serves as a flap-valve which shuts off the mouth from the oropharynx
The larynxhollow
musculoligamentous structure with a cartilaginous framework that caps the lower respiratory tract.
The cavity is continuous below with the trachea, & above opens into pharynx immediately posterior & inferior to the tongue
The larynx is both a valve (or sphincter) to close the lower respiratory tract, and an instrument to produce sound.
It is composed of: 3 large unpaired
cartilages (cricoid, thyroid, and epiglottis).
3 pairs of smaller paied cartilages (arytenoid, corniculate, and cuneiform).
a fibroelastic membrane and numerous intrinsic muscles.
The thyroid cartilage the largest one formed by right & left lamina,
which are widely separated posteriorly, but converge and join anteriorly.
They meet at laryngeal prominence ('Adam's apple').
more apparent in men than women.
The cricoid cartilagemost inferior one completely encircles
the airway It is shaped like a
'signet ring' Landmark for
tracheostomy.
The cricoid cartilage has two articular
facets on each side for articulation with other laryngeal cartilages.
1.one facet posteriorly articulation with arytenoid cartilage
2.Lateraly facet articulation with the thyroid cartilage.
Epiglottis
a 'leaf-shaped' cartilage attached to the thyroid cartilage.
The upper margin of the epiglottis is behind the pharyngeal part of the tongue.
The sides are attached to the arytenoid cartilages by aryepiglottic folds
Arytenoid cartilagesare pyramid-shaped cartilages with three surfaces, a
base of arytenoid cartilage, an apex of arytenoid cartilage, vocal process, and muscular process
Articulate with cricoid cartilage
Corniculate articulate with arytenoid cartilages & attach to aryepiglottic folds
Cuneiform found the fold to give strength to it
The ligaments of the The ligaments of the LarynxLarynx
Thyrohyoid membrane Connect thyroid cartilages
with hyoid bone. Opening on in the lateral part
of on each side for superior laryngeal arteries, nerves,
Posteriorly thickened lateral thyrohyoid ligaments.
thickened anteriorly form the median thyrohyoid ligament.
Cricotracheal ligament connect cricoid to 1st ring to trachea
Quadrangular membrane:extends between
epiglottis & arytenoid cartilages
its inferior margin forms the vestibular ligament covered by vestibular fold (false vocal cord)
Cricothyroid ligament its lower margin is attached to cricoid
cartilage Extend superiorly as a free margin
within the thyroid cartilage It forms the important vocal ligament
on each side. This ligament is covered by vocal
folds (true vocal cords) The anterior end of each vocal
ligament is attached to the thyroid cartilage, and the posterior end is attached to vocal process of the arytenoid cartilage.
Division into three major regionsTwo pairs of mucosal
folds, the vestibular (pink) and vocal folds (white), which project medially from the lateral walls of the laryngeal cavity constrict it and divide it into three major regions
the vestibule, a middle chamber the infraglottic cavity
Inlet of the Larynxopening is wider in front
than behind Bounded by: in front by epiglottis laterally by the
aryepiglottic foldposteriorly by arytenoid,
corniculate and cuneiform cartilages.
The Piriform Fossais a recess on
either side of the fold & inlet
It is bounded medially by aryepiglottic fold laterally by thyroid cartilage & thyrohyoid membrane
laryngoscope2 triangularshaped opening:rima vestibuli between two adjacent
vestibular folds rima glottidis between the two adjacent
vocal folds).
muscles of the larynx cricothyroid musclesVocalisPosterior cricoarytenoidLateral cricoarytenoidTransverse arytenoidThyro-arytenoidOblique arytenoid
Actions on the vocal folds
LARYNGEAL MUSCLES:
Cricothyroid musclesThe fan-shaped
cricothyroid muscles arch of the cricoid
cartilage to the thyroid cartilage
External branch of superior laryngeal nerve from the vagus nerve [X]
Stretch the vocal cords
Thyro-arytenoid muscle Posterior
cricoarytenoidLateral
cricoarytenoidTransverse
arytenoidOblique
arytenoidThyro-arytenoidVocalis
NervesSensory Nerves:Above the vocal cords: internal laryngeal branch of the superior laryngeal branch of the vagus●Below level of the vocal cords: The recurrent laryngeal nerve
Motor Nerves
All the intrinsic muscles of the larynx except the cricothyroid muscle are supplied by the recurrent laryngeal nerve.
The cricothyroid muscle is supplied by external laryngeal branch of the superior laryngeal branch of the vagus.
Superior laryngeal nerves The superior laryngeal nerves
originate from the inferior vagal ganglia
descend and divide into internal and external branches just above the level of the superior horn of the hyoid bone:
the external branch (external laryngeal nerve) supplying the cricothyroid muscle;
the internal branch (internal laryngeal nerve) penetrate the thyrohyoid membrane it is mainly sensory and supplies the laryngeal cavity down to the level of the vocal folds.
The recurrent laryngeal nerve
sensation to the inferior half of the larynx Motor to intrinsic laryngeal musculature. (not CT)
BLOOD SUPPLY The superior
laryngeal artery is a branch of the superior thyroid artery, derived from the external carotid artery
The inferior laryngeal artery derived from the inferior thyroid artery, which originates from the thyrocervical trunk of the subclavian artery.