Theme 6 Flashcards
Pharynx and Larynx
The Pharyngeal Wall
- Use
- What are the layers of the pharyngeal wall?
- Common passageway for food & air
- There are 4 layers:
Areolar: external fascial containing the pharyngeal plexus (of veins & nerves)
Muscular: 5 paired muscles
- Circular & Longitudinal
- Superior, middle & inferior constrictors - allowing swallowing. Innervated by CNX
- Stylopharyngeus & Palatopharyngeus
Submucous
Muscosa
Semi-Circular Constrictor Muscles of the Pharynx
- Function
- Muscles
- Innvervation
- Swallowing
- All the muscles, posteriorly attach to the Pharyngeal Raphe
(which is attached to the pharyngeal tubercle)
Superior Constrictor:
Anterior attachments: Pterygomandibular Raphe, Post. border of Medial Pterygoid plate & posterior part of the mylohyoid line
Middle Constrictor: Between both horns of hyoid bone - overlapping the S.C muscle above
Inferior Constrictor: has 2 parts. Originate from Thyroid & Circoid
- Thyropharyngeal: from thyroid cartilage oblique line
- Cricopharyngeus: always closed (due to cricopharyngeus sphincter) relaxes during swallowing
- CNX
What are the three regions that compose the Interior of Pharynx?
- Nasopharynx
- Oropharynx
- Laryngopharynx
Nasopharynx
- Where is it located?
- Where is the opening located?
- What structures are located within it?
- Superior portion of the pharynx found above the soft palate
- Opening of auditory tube is located in the lateral wall, posterior & inferior to the inferior nasal concha
3.
Salpingopharyngeal Fold: Small, mucous covered muscle; part of palatopharyngeus a
Pharyngeal Recess: a cleft between the salpingopharyngeal wall & posterior wall of the pharynx
Pharyngeal tonsils
Oropharynx
- Where is it located?
- What does it contain?
- located beneath the soft palate
2.
- Palatopharyngeal arch
- Palatopharyngeal fold
- Palatoglossal fold/arch
- Palatine tonsils - found between the arches
Laryngopharynx
What structures are found within?
What is the function of these structures?
Epiglottis: covers laryngeal inlet
Vallecula: gap between the epiglottis & tongue where things can fall.
- Bounded by Lat. & Median glossoepiglottic folds
Periform Excess: directs food & water from the lateral channels into esophagus
What is Waldeyer’s Tonsillar Ring?
Ring of Tonsillar tissue in the pharynx at the back of the oral cavity
Longitudinal Muscles of the Pharynx
Palatopharyngeus
- From soft palate to pharynx wall, Hyoid & Thyroid cartilages
Stylopharyngeus IX
Function: act to raise Pharynx & Larynx during swallowing (as do the suprahyoids)
Innervation of the Pharynx
Motor:
All by Pharyngeal branch of CNX BUTStylopharyngeus is CNIX
Sensory:
CNIX: around mucosa
CNV2: soft palate & pharyngeal roof
CNX: around the laryngeal inlet
Blood Supply of the Pharynx
- Ascending Pharyngeal Artery
- Superior Thyroid Artery
- Inferior Thyroid Artery
Venous drainage of the Pharynx
Pharyngeal venous plexus into internal jugular vein
Muscles of the Soft Palate
- What are they?
- What are their functions?
Levator Veli Palatini: Elevates soft palate
- Opening of the pharyngotympanic tube into the palatine aponeurosis (Soft palate)
Tensor Veli Palatini: Elevates soft palate
- via the medial pterygoid & Hamulus
Palatopharyngeus: Raises pharynx & larynx in swallowing
- Longitudinal pharynx muscle
- Forms palatopharyngeal arch after attachment with Hyoid & Thyroid cartilage
Palatoglossus: raises tongue & lowers soft palate
- From palatoglossal fold to the side of the tongue = palatoglossal arch
Innervation of the Soft Palate
Sensory:
Soft palate = Lesser Palatine
Motor:
Muscles = Pharyngeal plexus
Tensor Veli Palatini = CNV3
Stages of Swallowing
What tongue muscles are involved?
- Oral: Voluntary
- Mastication
- Tongue forms food into a bolus
- Tongue pushes bolus into oropharynx
- Pharyngeal: involuntary
- Soft Palate raised = Nasopharynx sealed off
- Longitudinal muscles contract
- Suprahyoids contract
- = raising of pharynx & larynx
3.
- Constrictor muscles contract
4.
- Cricopharyngeus relaxes to allow the bolus to enter Oesophagus
- Peristalsis of the Oesphargeal wall
Tongue muscles involved: palatoglossus, styloglossus, palatopharyngeal, hyoglossus & geniohyoid
Laryngeal Cartilages
Unpaired
C3-C4 level: under Adams apple
- Epiglottis
- Cricoid cartilage
- Thyroid cartilage
Paired
- Arytenoid
- Sits on posterior cricoid bt facet on its
- Leans against the posterior wall of thyroid
- Corniculate
- Elastic
- Cuneiform
- Elastic
- Thickenings within the quadrangular membrane
What are the Extrinsic & Intrinsic Laryngeal Membranes?
Extrinsic:
- Cricotracheal
- Thyrohyoid
Intrinsic:
- Conus elasticus (cricothyroid)
- Quadrangular (aryepiglottic)
Cricothyroid Joint
- What type of joint is it?
- Where is it located?
- How does it function?
- Synovial: has a capsule
2.
- Inferior cornu of thyroid cartilage
- Facet on cricoid cartilage
3.
- Rotation about an axis between the two inferior cornuae & some gliding
- Lengthen & shorten vocal folds
Cricoartenoid Joint
- What type of joint is it?
- Where is it located?
- How does it function?
- Synovial
2.
- Facet on base of arytenoid
- Face on shoulder of cricoid
- Oval/concave/convex facet
- Cricoarytenoid ligaments & oblique line is part of this joint
3.
- Rocking & sliding
- Open & close vocal folds (abduction & adduction)
How is the Laryngeal Inlet controlled?
Aryepiglottic: contracts to close the inlet by drawing down the epiglottis
Thyroepiglottic: closes inlet
How are the Vocal Folds controlled?
Posterior cricoarytenoid (abduction)
- Inferiorly attached to post. Aspect of the lamina of the cricoid fossa
- Superiorly attached to the muscular process of the arytenoid cartilage
Lateral cricoarytenoid (adduction)
Interarytenoid (adduction)
How is it lengthened & shortened?
Cricothyroid (lengthen)
- Contained numerous glands that secrete mucous and protect true vocal folds by keeping them moist
Thyroarytenoid (shorten)
Motor Innervation of Larynx
Two nerves, branches of vagus nerve
Recurrent Laryngeal:
- Motor to all intrinsic muscles apart from cricothyroid
External Laryngeal (of superior laryngeal)
- Cricothyroid muscle
Sensory Innervation of Larynx
Important in protective reflexes & voice production
Recurrent laryngeal: - below the vocal fold
To the mucous membrane covered true vocal folds and infraglottic cavity below vocal folds
- Right: turns & passes under the right subclavian artery
- Left: turns & passes under & around the aortic arch and then runs upwards
Internal Laryngeal: - above vocal folds
To the mucous membrane of the cavity of the larynx above the true vocal folds
What are the different cavities found in the larynx?
Vestibule: supraglottic
- Pits at the back of Epiglottis
- Above true & false vocal folds
Ventricle: Laryngeal sinus
- Keeps vocal cords moist
- Sit between ventricular and vocal ligaments
- Lies between true & false vocal folds
Infraglottic:
- A comparement of the larnyx
- Lies below the true vocal folds
Functions of the Larynx
- Ventilatory when fully open - Inspiration & expiration
- Phonatory when Half open
- Voice production
- Articulation
- Sphincteric when fully closed
- Protection from swallowing
- Fixation in thorax
- Regulation of abdominal pressure
- Ingestion of foreign bodies
Phonation
- What is Phonation?
- How does Phonation occur?
- What is the role of Arytenoids?
- Voice Production
2.
- Vocal folds adducted during expiration
- Pressure Rises
- Vocal fold abduct & air is released
- Vocal folds adduct & cycle repeats
3.
Rotation of arytenoids open and closes vocal cord
- Normal breathing: vocal opening is diamond shape
- Forced respiration: vocal opening widens
- Phonation: vocal opening is closed
When does the Larynx provide protection? & How?
During swallowing:
- Larynx raises due to suprahyoids, infrahyoids & longitudinal muscles of the pharynx
- Epiglottis lowers passively
- Larynx inlet closes
- Vocal fold adduct
- Ventilation suspends
- Cough reflex
Cough reflex
- Foreign body enters supraglottic cavity/near to laryngeal inlet- could cause asphyxiation by obstructing the airways
- Presence of foreign body is detected by sensory receptors and relayed to brain
- Done by sensory innervation
- Initial deep inspiration so vocal folds are tightly closed
- Increase in thoracic pressure by forceful expiration against closed vocal folds
- Pressure below vocal folds rises
- Vocal folds suddenly abducted (opened)
- Foreign body dislodges by rapid rise in air pressure, spat out or swallowed
