Pharynx

Page 1: Introduction to the Pharynx

  • Pharynx Lecture by K. Rafferty, Ph.D.

    • Key divisions: Nasopharynx, Oropharynx, Laryngopharynx

Page 2: Learning Objectives on Pharynx Anatomy

  1. Define boundaries and sensory innervation of:

    • Nasopharynx

    • Oropharynx

    • Laryngopharynx

  2. Describe communications between pharynx regions, nasal cavity, oral cavity, larynx, and tympanic cavity.

  3. Outline infection pathways from pharynx to danger space (spaces and fascial layers involved).

  4. Identify locations of tonsils in Waldeyer’s tonsillar ring.

  5. Describe:

    • Attachments, innervation, and functions of three constrictor muscles and three vertical muscles of the pharynx.

  6. Explain how structures enter the pharynx through gaps between constrictor muscles.

  7. Discuss the role of "valves" in protecting the airway during food processing and swallowing.

Page 3: Definition of the Pharynx

  • Pharynx: Musculomembranous tube from base of skull to cricoid cartilage.

    • Functions as a passageway for air and food.

Page 4: Anatomical Attachments of the Pharynx

  • Attaches to the base of the skull at multiple locations:

    • Choanae (posterior openings of nasal cavities)

    • Medial plate of pterygoid process of sphenoid

    • Pterygoid hamulus

    • Scaphoid fossa on sphenoid (for tensor veli palatini attachment)

    • Cartilaginous positions on the petrous part of the temporal bone

    • Pharyngotympanic tube attachment (via levator veli palatini)

    • Carotid canal, jugular foramen, external auditory meatus, pharyngeal tubercle marked.

Page 5: Posterior View of Pharynx

  • Visual: Posterior wall of pharynx cut open, looking anteriorly into nasal and oral cavities, and larynx.

Page 6: Three Parts of the Pharynx

  • Relevant Regions:

    • Nasopharynx

    • Oropharynx

    • Laryngopharynx

Page 7: Structures of the Nasopharynx

  • Components:

    • Choanae

    • Soft palate

    • Torus tubarius & opening of pharyngotympanic tube

    • Pharyngeal tonsil (adenoids)

Page 8: Pharyngotympanic Tube Function

  • Connects to middle ear cavity.

    • Middle ear: Air-filled, mucous membrane lined.

    • Sound transmission: Tympanic membrane → chain of ossicles (malleus, incus, stapes) → oval window of inner ear.

Page 9: Ear Muscles and Their Roles

  • Two muscles:

    • Stapedius (CN VII): Damps vibrations, protecting inner ear from loud sounds.

    • Tensor Tympani (CN V3): Also dampens vibrations.

Page 10: Normal Ear Anatomy

  • Otoscope View: Right tympanic membrane annotated.

    • Components: Pars flaccida, lateral process of malleus, pars tensa, cone of light.

Page 11: Infections Related to Pharynx

  • Diseases: Pharyngitis and otitis media related structures.

    • Connection to mastoid antrum and air cells, and other specified regions.

Page 12: Muscles of the Soft Palate

  • Muscle Functions:

    • Palatoglossus: Depresses palate and elevates the tongue.

    • Palatopharyngeus: Moves palate posteriorly, elevates pharynx.

    • Tensor veli palatini: Tenses palate and opens pharyngotympanic tube.

    • Levator veli palatini: Elevates palate.

    • The soft palate acts as a valve in speech, food handling, and breathing operations.

Page 13: Structures Relative to the Oropharynx

  • Components:

    • Soft palate

    • Posterior part of tongue (with lingual tonsil)

    • Epiglottis

    • Oropharyngeal isthmus including palatine tonsils.

Page 14: Oropharynx Overview

  • Structures Identified: Palatoglossal arch, palatopharyngeal arch, palatine tonsil, uvula, lateral structures.

Page 15: Fascial Spaces and Infections

  • Infections Spread: Potential pathways and causes of infection.

    • Upper airway infections, trauma, odontogenic causes (especially lower posterior molar).

Page 16: Spread of Infection via Fascial Layers

  • Fascial Layers & Spaces:

    • Buccopharyngeal fascia

    • Alar fascia

    • Vertebral fascia

    • Danger Space: Extends from retropharyngeal space to mediastinum in the thorax.

Page 17: Laryngoscope View

  • Details structures including:

    • Epiglottis

    • Laryngopharynx

    • Laryngeal inlet

    • Esophagus

    • Piriform fossae.

Page 18: Waldeyer’s Ring Overview

  • Consists of Tonsils:

    • Palatine tonsils

    • Pharyngeal tonsil (adenoid)

    • Lingual tonsil

    • Tubal tonsil.

Page 19: Circular Constrictor Muscles

  • Three Muscles: Overlapping, closed by pharyngeal raphe.

    • Regions:

      • Cricopharyngeal part forms upper esophageal sphincter.

      • Inferior, middle, and superior constrictors defined by attachment markers.

Page 20: Constrictor Attachments

  • Detailed descriptions of anterior attachments of each pharyngeal constrictor.

Page 21: Pterygomandibular Raphe

  • Junction of buccinator and superior constrictor, important landmark for inferior alveolar nerve block.

Page 22: Longitudinal Pharyngeal Muscles

  • Three Muscles: Internal to constrictors, elevate the pharynx.

    • Innervation noted, specifying exceptions.

Page 23: Entry Points to the Pharynx

  • Gaps:

    • Above superior constrictor: Levator veli palatini, pharyngotympanic tube.

    • Between constrictors: Various nerves and muscles as structures enter.

Page 24: Sensory Distribution

  • Cranial Nerves:

    • V2, X, IX, recurrent laryngeal (X).

    • Clarification on muscle innervations relevant to pharynx.

Page 25: Pharynx Functionality

  • Dual Role: Common passage for air and food with safeguards:

    • Breathing and eating processes outlined; safety concerns highlighted.

Page 26: Protection Mechanisms

  • Valves for Airway Protection by various structures.

    • Role of oropharyngeal, velopharyngeal, and epiglottic actions during swallowing.

Page 27: Oropharyngeal Valve Dynamics

  • Mechanism during swallowing:

    • Tongue actions preventing bolus entry before swallowing.

Page 28: Velopharyngeal Valve Dynamics

  • Seals off nasal cavity: Mechanism involving soft palate and pharyngeal wall motions.

Page 29: Role of Epiglottis

  • Swallowing Mechanics: Epiglottis protects the airway, response to muscular actions.

Page 30: Airway Protection During Swallowing

  • Glottis Actions: Vocal folds and epiglottis roles defined during repeated swallowing actions.

Page 31: Phases of Swallowing

  1. Preparatory: Voluntary food bolus preparation.

  2. Oral Transport: Transfers bolus to pharynx, initially voluntary then reflexive.

  3. Pharyngeal: Involuntary propulsion of the bolus.

  4. Esophageal: Involuntary peristalsis in the esophagus.

Page 32: Visual of Normal Swallowing

  • Reference visualization of soft palate, epiglottis, hyoid in coordination.

Page 33: Dysphagia

  • Concern: Issues associated with dysphagia as a potential swallowing disorder.