Pharynx, Larynx & Lung Anatomy A whistle-stop tour By filip & James

Pharynx Middle Ear Nasopharynx Muscular region connecting the nasal and oral cavities with larynx and oesophagus Oropharynx Laryngopharynx

Pharynx is formed by 3x pharyngeal constrictors Reduce size of pharynx Squeeze food down pharynx (peristalsis) Superior constrictor Middle constrictor Inferior constrictor Paralysis causes lack of gag reflex, uncoordinated swallowing and increased risk of aspiration

Pharyngeal Constrictors Constrictors stack inside each other forming a structurally-sound functional unit Pharyngeal pouch/diverticulum can fill with food causing halitosis or coughing-up of food SC Midline Raphe (Similar to a long tendon) MC IC ‘Weak Spot’ Pharyngeal pouch / diverticulum

Pharynx – Internal Muscles Longitudinal (internal) muscles elevate (shorten) & widen pharynx Salpingopharyngeus SC Tensor veli palatini (CN Vc) Stylopharyngeus (CN IX) Palatopharyngeus MC Levator veli palatini IC All pharyngeal muscles Motor innervated by CNX except stylopharyngeaus & tensor veli palatini

Pharynx– innervation Motor: CNX (Vagus) Sensory: Superior laryngeal nerve Damage = Monotonous voice Recurrent (inferior) laryngeal nerve Damage = hoarse/weakened voice Sensory: CN IX

Lymphoid Tissue - Tonsils Palatoglossal & paltopharyngeal arches Palatine tonsil Tunstall & Shah 2012 Pocket Tutor: Surface Anatomy

Tonsillar (lymphoid) tissue sits in the entrances to the pharynx Pharyngeal (Adenoid) Tubal Palatine Lingual Collectively known as Waldeyer ring of lymphoid tissue

Larynx What is the function of the larynx? (4) Prevents entrance of fluid and particles Allows regulation of intrathoracic & intra-abdominal pressure (Valsava manoeuvre) Enables phonation (production of sound) Speech articulation is controlled by the pharynx, tongue & lips

Larynx – Bone & Cartilages Hyoid bone Epiglottis (elastic cartilage) Thyrohyoid membrane Laryngeal prominence Arytenoid cartilage Thyroid cartilage Cricoid cartilage Cricoid cartilage Cricothyroid membrane (emergency airway)

Arytenoids as viewed from above in transverse section Larynx – Arytenoids & Vocal Folds Anterior Vocal Process Arytenoid cartilages Articulate with cricoid cartilage via synovial joint that permit pivoting movements Joint position Muscular Process Posterior Cricovocal membrane Thickened free edge = vocal ligament Arytenoids as viewed from above in transverse section

Superior Laryngeal Nerve (Internal laryngeal n.) (External laryngeal nerve) Posterior Anterior Cricothyroid Pivots thyroid cartilage forward and down on the cricoid & tenses the vocal folds

Lateral cricoarytenoid muscle Posterior cricoarytenoid muscle Recurrent Layrngeal Nerve Posterior cricoarytenoid muscle Lateral cricoarytenoid muscle Ant. Lateral cricoarytenoid muscle (adducts vocal ligaments) Ant. Post. Posterior cricoarytenoid muscle (abducts vocal ligaments) Post.

Relaxes vocal fold (or parts of it) and lowers pitch of voice Recurrent Layrngeal Nerve Ant. Thyroarytenoid & vocalis Pull arytenoid cartilage anteriorly & thyroid cartilage posteriorly and superiorly Relaxes vocal fold (or parts of it) and lowers pitch of voice Post.

(gap between vocal folds) Anterior Epiglottis Vestibular folds (false vocal folds) Aryepiglotic fold Rima glottidis (gap between vocal folds) Vocal Folds Posterior

What makes up the TBT? Trachea Bronchi Bronchioles Terminal bronchioles Alveolar ducts Alveolar sacs Alveoli

LUNGS What do structures entering the lung pass through? Hilum What two layers form the pleura of the lungs? Visceral Parietal What holds the pleura together? Surface tension

Right lung has 3 lobes and the left has 2 lobes Oblique fissure Oblique fissure Superior Lobe Superior Lobe Middle Lobe Lingula Inferior Lobe Inferior Lobe Horizontal fissure Disease/collapse/atelectasis can affect lobes independently

Apex sits ~2cm above medial 1/3 of clavicle Lung Surface Markings Apex sits ~2cm above medial 1/3 of clavicle Tunstall & Shah 2012 Pocket Tutor: Surface Anatomy 2cc Note the tracheal bifurcation at sternal plane or just below T4/T5 Horizontal fissure: 4thcc horizontally back to oblique fissure 6cc Oblique Fissure: T3 Spinous Process to 6th cc anteriorly 6rib MCL 8 rib MAL Costodiaphragmatic recess The region between the lung and pleura reflection Lung is soft and compliant so will fill many empty spaces in the thorax

Penetrating damage to lung tissue can cause pneumothorax Lung Surface Markings Tunstall & Shah 2012 Pocket Tutor: Surface Anatomy Upper lobe Oblique Fissure: T3 Spinous Process to 6th cc anteriorly Auscultate lower lobe of lung posteriorly Lower lobe 10 rib PVL - lung 12 rib PVL - pleura Penetrating damage to lung tissue can cause pneumothorax

Auscultate middle lobe of lung laterally Lower lobe Lung Surface Markings Tunstall & Shah 2012 Pocket Tutor: Surface Anatomy Mid-axillary line Upper lobe Horizontal fissure: 4thcc horizontally back to oblique fissure Middle lobe Auscultate middle lobe of lung laterally Oblique Fissure: T3 Spinous Process to 6th cc anteriorly Lower lobe

Right lymphatic duct /subclavian vein Lymphatic drainage Lymphatic drainage from the lungs follows the tracheobronchial tree Right lymphatic duct /subclavian vein All lymph except left upper lobe Thoracic duct/left subclavian vein Left upper lobe Bronchomediastinal duct Paratracheal nodes Hilar/bronchopulmonary nodes Tracheobronchial nodes