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The pharynx is a fibromuscular tubular structure forming the upper part of the digestive and respiratory tracts. It serves as a common pathway for air and food and connects the nasal and oral cavities to the larynx and esophagus.
The pharynx is commonly called the throat. It is the passage through which:
Air travels from nose → larynx → trachea
Food travels from mouth → esophagus → stomach
The pharynx extends:
| Superior Limit | Inferior Limit |
|---|---|
| Base of skull (body of sphenoid and basilar part of occipital bone) | Lower border of cricoid cartilage (C6 vertebra) where it continues as esophagus |
Approximately 12–14 cm in adults
Funnel-shaped fibromuscular tube
Wider above
Narrower below
This funnel shape facilitates:
Passage of food into esophagus
Efficient conduction of inspired air
| Part | Approximate Width |
|---|---|
| Upper pharynx | 5 cm |
| Lower pharynx | 1.5–2 cm |
Adults: 12–14 cm
Children: Relatively shorter
The pharynx is divided into three anatomical regions:
Behind nasal cavity
Above soft palate
Respiratory function
Behind oral cavity
Between soft palate and upper border of epiglottis
Behind larynx
Extends from epiglottis to cricopharyngeus
Continues as esophagus
Insert Diagram
Sagittal section showing:
Nasopharynx
Oropharynx
Hypopharynx
Soft palate
Epiglottis
Larynx
Esophagus
The upper aerodigestive tract (UADT) includes structures involved in:
Respiration
Deglutition
Speech
Nasal cavity
Paranasal sinuses
Nasopharynx
Oropharynx
Hypopharynx
Larynx
Oral cavity
Common diseases affect multiple UADT sites simultaneously:
Examples:
Tobacco-related malignancies
HPV-associated cancers
Chronic infections
GERD-related pathology
The pharynx develops from:
Forms:
Pharyngeal mucosa
Tonsillar epithelium
Forms:
Muscles
Connective tissues
Form:
Cartilages
Skeletal components
Development occurs through:
Primitive foregut
Pharyngeal arches
Pharyngeal pouches
Pharyngeal clefts
Acts as an air passage.
Conducts inspired air
Humidifies air
Warms air
Filters particles
Mainly:
Nasopharynx
Acts as a food passage.
Initiation of swallowing
Propulsion of bolus toward esophagus
Constrictor muscles
Longitudinal muscles
Important for speech production.
Directs expired air toward larynx
Participates in velopharyngeal closure
Velopharyngeal insufficiency causes:
Hypernasal speech
Nasal regurgitation
Pharynx acts as a resonance chamber.
Voice quality
Tone
Timbre
Altered in:
Adenoid hypertrophy
Nasopharyngeal tumors
Palatal defects
Protects lower respiratory tract.
Prevents aspiration.
Expels foreign material.
Prevents food entering nose.
Prevents aspiration.
Provided mainly by:
Includes:
Adenoids
Tubal tonsils
Palatine tonsils
Lingual tonsils
Antigen recognition
B-cell activation
IgA production
Mucosal immunity
| Function | Role |
|---|---|
| Respiratory | Air passage |
| Digestive | Food passage |
| Phonatory | Speech |
| Resonance | Voice quality |
| Protective | Prevent aspiration |
| Immunological | Local immunity |
The pharynx is involved in numerous ENT disorders.
Adenoid hypertrophy
Nasopharyngeal carcinoma
OME
Tonsillitis
Peritonsillar abscess
Oropharyngeal cancers
Pyriform fossa carcinoma
Dysphagia disorders
Foreign bodies
Adenoidectomy
Tonsillectomy
UPPP
Endoscopic pharyngeal surgeries
During the 4th week of embryonic life:
Primitive gut tube develops from endoderm.
Cranial part forms foregut.
The foregut gives rise to:
Pharynx
Esophagus
Stomach
Upper duodenum
Respiratory diverticulum
The pharyngeal apparatus consists of:
Pharyngeal arches
Pharyngeal pouches
Pharyngeal clefts (grooves)
Pharyngeal membranes
Appears during:
4th to 5th week
There are six arches embryologically.
Fifth arch is rudimentary and disappears.
Functional arches:
1st
2nd
3rd
4th
6th
Each arch contains:
Cartilage
Muscle
Artery
Cranial nerve
Trigeminal nerve (CN V)
Muscles of mastication
Mylohyoid
Tensor veli palatini
Tensor tympani
Maxilla
Mandible
Malleus
Incus
Facial nerve (CN VII)
Facial expression muscles
Stapedius
Stylohyoid
Posterior belly digastric
Stapes
Styloid process
Lesser horn of hyoid
Glossopharyngeal nerve (CN IX)
Stylopharyngeus
Greater horn of hyoid
Superior laryngeal nerve (CN X)
Cricothyroid
Levator veli palatini
Pharyngeal constrictors
Laryngeal cartilages
Recurrent laryngeal nerve (CN X)
Intrinsic muscles of larynx except cricothyroid
Laryngeal cartilages
| Arch | Nerve | Main Muscle |
|---|---|---|
| 1st | CN V | Muscles of mastication |
| 2nd | CN VII | Facial muscles |
| 3rd | CN IX | Stylopharyngeus |
| 4th | CN X (SLN) | Cricothyroid |
| 6th | CN X (RLN) | Intrinsic laryngeal muscles |
Endodermal outpouchings.
Eustachian tube
Middle ear cavity
Palatine tonsil epithelium
Inferior parathyroid
Thymus
Superior parathyroid
Ultimobranchial body
Ectoderm-lined grooves.
Forms:
External auditory canal
Normally disappear.
Failure leads to:
Branchial cysts
Sinuses
Fistulae
Formed by:
Ectoderm + Endoderm
Forms:
Tympanic membrane
Remaining membranes disappear.
Insert Flowchart
Arch → Nerve → Muscle → Skeletal Derivative
Insert Flowchart
Pouch 1 → Middle ear & ET
Pouch 2 → Tonsil
Pouch 3 → Thymus + Inferior Parathyroid
Pouch 4 → Superior Parathyroid + C cells
Develops from:
Cranial pharynx
Nasal cavities
Separated from oral cavity by:
Soft palate
Develops from:
Middle part of primitive pharynx
Communicates with oral cavity via:
Oropharyngeal isthmus
Develops from:
Caudal primitive pharynx
Closely associated with:
Laryngeal development
Palatine tonsils arise from:
Second pharyngeal pouch endoderm
Lymphoid tissue infiltrates later.
Develops from:
Mucosal lymphoid aggregation
Includes:
Adenoid
Tubal tonsils
Palatine tonsils
Lingual tonsils
Persistence of cervical sinus.
Anterior border of SCM.
Painless lateral neck swelling.
Blind tract opening externally or internally.
Persistent communication between:
Skin
Pharynx
Usually second arch origin.
Associated with:
External auditory canal
Parotid region
Most common.
Includes:
Cysts
Sinuses
Fistulae
May present as:
Recurrent neck infection
Pyriform sinus tract
Cause:
Recurrent suppurative thyroiditis
Usually left sided.
Thin congenital membrane causing:
Dysphagia
Airway obstruction
Include:
Tornwaldt cyst
Choanal atresia
Nasopharyngeal cysts
Congenital stenosis
The pharynx is a fibromuscular tube extending from the skull base to the lower border of the cricoid cartilage.
Base of skull
Lower border of cricoid cartilage (C6)
Posterior nasal apertures
Oral cavity
Laryngeal inlet
Prevertebral fascia
Cervical vertebrae
Carotid sheath
Parapharyngeal space
Behind nose.
Behind oral cavity.
Behind larynx.
Communication between nasopharynx and oropharynx.
Soft palate
Posterior pharyngeal wall
Regulates airflow
Prevents nasal regurgitation
Innermost layer.
Contains glands and vessels.
Fibrous layer replacing muscle superiorly.
Superior constrictor
Middle constrictor
Inferior constrictor
Stylopharyngeus
Palatopharyngeus
Salpingopharyngeus
Outer fascial covering.
Insert Cross-sectional Diagram
Showing all five layers.
Small pharynx
Large adenoids
High larynx
Prominent lymphoid tissue
Fully developed dimensions
Maximum functional efficiency
Muscle atrophy
Reduced swallowing efficiency
Reduced gag reflex
Increased aspiration risk
From:
Base of skull
To:
Upper surface of soft palate
Body of sphenoid
Basilar occipital bone
Pharyngeal tonsil (adenoid)
Soft palate
Posterior choanae
Upper cervical vertebrae
Pharyngeal tonsil
Contains Eustachian tube opening and associated structures.
Located on:
Roof and posterior wall
Function:
Immunological defense
Elevation produced by:
Cartilaginous end of Eustachian tube
Situated on lateral wall.
Function:
Ventilation of middle ear
Contains:
Salpingopharyngeus muscle
Runs from torus to soft palate.
Lymphoid tissue around tubal opening.
Deep recess behind torus tubarius.
Most common site of origin of:
Nasopharyngeal carcinoma
Include:
Pharyngeal recess
Tubal recesses
Main muscle opening Eustachian tube.
Supports tube function and palate elevation.
Insert Diagram
Lateral wall of nasopharynx showing:
Torus tubarius
ET opening
Fossa of Rosenmüller
Tubal tonsil
Salpingopharyngeal fold
Branches of:
Ascending pharyngeal artery
Ascending palatine artery
Facial artery
Maxillary artery
Via:
Pharyngeal venous plexus
Drains into:
Internal jugular vein
Drains mainly to:
Retropharyngeal nodes
Upper deep cervical nodes
Jugulodigastric nodes
Predominantly:
Pharyngeal branch of maxillary nerve (V2)
Via:
Pharyngeal plexus
Mouth breathing
Snoring
Nasal obstruction
Hyponasal speech
OME
Nasal endoscopy
X-ray nasopharynx (lateral)
Adenoid hypertrophy may obstruct:
Eustachian tube
Leading to:
Negative middle ear pressure
Effusion
Fossa of Rosenmüller
Neck node
Nasal obstruction
Epistaxis
Serous otitis media
Cranial nerve palsy
Any unilateral OME in an adult must raise suspicion of nasopharyngeal carcinoma until proven otherwise.
The oropharynx is the middle part of the pharynx.
Lower surface of soft palate
Upper border of epiglottis
Level of hyoid bone (approximately C2–C3 vertebra)
Soft palate
Upper border of epiglottis
Communicates with oral cavity through the oropharyngeal isthmus.
Formed by:
Soft palate
Uvula
Faucial pillars
Posterior pharyngeal wall
Tonsillar fossae
Palatine tonsils
A mobile fibromuscular fold suspended from the posterior edge of the hard palate.
Separates nasopharynx from oropharynx during swallowing
Important in speech and resonance
Prevents nasal regurgitation
Tensor veli palatini
Levator veli palatini
Musculus uvulae
Palatopharyngeus
Palatoglossus
Conical projection hanging from the posterior border of soft palate.
Assists velopharyngeal closure
Contributes to speech resonance
Helps direct secretions
Two mucosal folds extending from soft palate.
Contains:
Palatoglossus muscle
Contains:
Palatopharyngeus muscle
Situated in tonsillar fossa between:
Anterior pillar
Posterior pillar
Largest component of Waldeyer's ring
Rich lymphoid tissue
Contains multiple crypts
Antigen presentation
Local immunity
IgA production
Posterior one-third of tongue.
Rich lymphoid tissue
Lingual tonsils
Valleculae
Common site for:
Oropharyngeal carcinoma
Lingual tonsillitis
Mucosal depression between:
Base of tongue
Epiglottis
Common site for foreign body impaction
Important landmark during laryngoscopy and intubation
Triangular recess containing palatine tonsil.
Palatoglossal arch
Palatopharyngeal arch
Soft palate
Tongue
Structures deep to palatine tonsil.
Tonsillar capsule
Loose areolar tissue
Superior constrictor muscle
Buccopharyngeal fascia
| Structure | Clinical Importance |
|---|---|
| Glossopharyngeal nerve | Referred otalgia after tonsillectomy |
| Facial artery branches | Hemorrhage |
| Internal carotid artery | Rare surgical danger |
Mainly from:
Tonsillar branch of facial artery
Ascending palatine artery
Ascending pharyngeal artery
Dorsal lingual artery
Greater palatine artery
Via:
Peritonsillar venous plexus
Pharyngeal venous plexus
Drain into:
Internal jugular vein
Primarily to:
(Tonsillar node)
Most important lymph node.
Upper deep cervical nodes
Mainly:
Glossopharyngeal nerve (CN IX)
Through:
Pharyngeal plexus
Most common inflammatory disease.
Occurs in peritonsillar space.
Associated with enlarged tonsils.
Common sites:
Tonsil
Base of tongue
Most frequently performed ENT surgery.
Insert Labelled Diagram
Showing:
Soft palate
Uvula
Faucial pillars
Palatine tonsil
Tonsillar fossa
Base of tongue
Vallecula
The hypopharynx is the lowest part of the pharynx.
Upper border of epiglottis
Lower border of cricoid cartilage (C6)
Where it continues as:
Esophagus
Pharyngoepiglottic folds
Cricopharyngeus
Laryngeal inlet
Larynx
Posterior pharyngeal wall
Pyriform fossae
Pear-shaped mucosal recess situated on either side of laryngeal inlet.
Most clinically important hypopharyngeal subsite.
Aryepiglottic fold
Laryngeal inlet
Thyrohyoid membrane
Thyroid cartilage
Apex leading into esophagus
The internal laryngeal nerve and superior laryngeal vessels lie beneath the mucosa of the lateral wall.
Foreign body removal may injure:
Internal laryngeal nerve
Resulting in:
Loss of supraglottic sensation
Especially:
Fish bones
Important during:
Esophagoscopy
Laryngoscopy
Mainly from:
Superior thyroid artery
Inferior thyroid artery
Ascending pharyngeal artery
Drains into:
Pharyngeal venous plexus
Internal jugular vein
Drains to:
Upper deep cervical nodes
Middle deep cervical nodes
Early lymphatic metastasis is common.
Internal laryngeal nerve
(branch of superior laryngeal nerve)
Pharyngeal plexus
Fish bones commonly lodge here.
Particularly pyriform sinus carcinoma.
Common symptom in lesions.
Via vagal and glossopharyngeal pathways.
Essential in:
Dysphagia
Suspected malignancy
Insert Labelled Diagram
Showing:
Pyriform fossae
Postcricoid region
Posterior pharyngeal wall
Laryngeal inlet
Internal laryngeal nerve
The pharyngeal wall consists of:
Mucosa
Submucosa
Pharyngobasilar fascia
Muscular layer
Buccopharyngeal fascia
Different regions have different epithelial lining depending on function.
Type:
Pseudostratified ciliated columnar epithelium
Contains:
Ciliated cells
Goblet cells
Basal cells
Mucociliary clearance
Air filtration
Humidification
Produce mucus.
Traps dust
Traps microorganisms
Maintains moisture
Adapted for:
Friction
Swallowing
Protects against:
Mechanical trauma
Food abrasion
Designed to withstand:
Mechanical stress
Passage of food bolus
Located in:
Submucosa
Functions:
Lubrication
Humidification
Protection
Particularly abundant in:
Includes:
Adenoids
Tubal tonsils
Palatine tonsils
Lingual tonsils
Functions:
Antigen trapping
Immunity
IgA secretion
| Feature | Nasopharynx | Oropharynx | Hypopharynx |
|---|---|---|---|
| Epithelium | Respiratory | Stratified squamous non-keratinized | Stratified squamous |
| Goblet cells | Present | Absent | Absent |
| Cilia | Present | Absent | Absent |
| Main Function | Respiration | Mixed | Deglutition |
Insert Histology Plate
Showing:
Respiratory epithelium
Stratified squamous epithelium
Goblet cells
Lymphoid follicles
The pharyngeal muscles are divided into:
Circular muscles (Constrictors)
Longitudinal muscles (Elevators)
Arranged externally.
Pterygoid hamulus
Pterygomandibular raphe
Mandible
Pharyngeal raphe
Initiates pharyngeal contraction.
Greater horn of hyoid
Lesser horn of hyoid
Pharyngeal raphe
Propels food downward.
Largest constrictor muscle.
Divided into:
Origin:
Oblique line of thyroid cartilage
Fiber direction:
Oblique
Origin:
Cricoid cartilage
Fiber direction:
Horizontal
Forms:
Upper esophageal sphincter
Fibrous median line extending from:
Pharyngeal tubercle
to
Esophagus
Provides insertion to constrictor muscles.
Located internally.
Styloid process
Glossopharyngeal nerve
Elevates pharynx during swallowing.
Soft palate
Elevates pharynx and larynx.
Cartilage of Eustachian tube
Elevates pharynx.
Propel bolus downward
Elevate pharynx and larynx
Relaxes to allow entry into esophagus
| Muscle | Action |
|---|---|
| Superior constrictor | Initiates propulsion |
| Middle constrictor | Continues propulsion |
| Inferior constrictor | Final propulsion |
| Stylopharyngeus | Elevation |
| Palatopharyngeus | Elevation |
| Salpingopharyngeus | Elevation |
Insert Labelled Muscle Diagram
Showing:
Superior constrictor
Middle constrictor
Inferior constrictor
Stylopharyngeus
Palatopharyngeus
Salpingopharyngeus
The upper esophageal sphincter (UES) is a physiological high-pressure zone at the pharyngoesophageal junction.
Located at:
C5–C6 vertebral level
Principal component.
Contributed by:
Thyropharyngeus
Adjacent fibers
UES remains tonically contracted.
Functions:
Prevents air entry into esophagus
Prevents reflux into pharynx
Occurs during swallowing.
Sequence:
Cricopharyngeal relaxation
Laryngeal elevation
Bolus passage
Sphincter closure
Causes:
Dysphagia
Failure of relaxation.
Occurs above UES.
Treatment for selected dysphagia disorders.
Insert Diagram
Showing:
Inferior constrictor
Cricopharyngeus
UES
Esophagus
Oblique fibers of:
Thyropharyngeus
Transverse fibers of:
Cricopharyngeus
Area of muscular weakness between two parts of inferior constrictor.
Located in:
Posterior hypopharyngeal wall
Site of origin of:
(Pulsion diverticulum)
Dysphagia
Regurgitation
Halitosis
Aspiration
Cricopharyngeus
Upper esophagus
Longitudinal esophageal fibers
Another area of weakness.
Rare site of:
Laimer's diverticulum
Located below cricopharyngeus.
Situated on anterolateral wall of cervical esophagus.
Arises through this area.
Closely related to:
Recurrent laryngeal nerve
Risk of nerve injury during surgery.
| Area | Location | Clinical Significance |
|---|---|---|
| Killian's dehiscence | Between thyropharyngeus and cricopharyngeus | Zenker's diverticulum |
| Laimer's triangle | Below cricopharyngeus posteriorly | Rare diverticulum |
| Killian–Jamieson area | Anterolateral cervical esophagus | Killian–Jamieson diverticulum |
Pharyngeal spaces are fascial planes surrounding the pharynx. They are of great clinical importance because infections, abscesses, and tumors may spread through these spaces.
A potential space situated behind the pharynx and in front of the prevertebral fascia.
Buccopharyngeal fascia covering the posterior pharyngeal wall
Alar fascia
Carotid sheaths
Base of skull
Approximately T1–T2 vertebral level
Present mainly in:
Infants
Young children
Common in children due to:
Suppuration of retropharyngeal lymph nodes
Upper respiratory infections
Adenoid infections
Tonsillitis
Trauma
Airway obstruction
Aspiration
Mediastinitis
Septicemia
Fever
Dysphagia
Odynophagia
Neck stiffness
Torticollis
Respiratory distress
A potential fascial space posterior to the retropharyngeal space.
Named "Danger Space" because infection can spread directly into the posterior mediastinum.
Alar fascia
Prevertebral fascia
Fusion of fascial layers
Base of skull
Diaphragm
Severe neck infections may spread rapidly into:
Posterior mediastinum
Thoracic cavity
Potentially life-threatening.
An inverted pyramid-shaped fascial space located lateral to the pharynx.
Skull base
Greater cornu of hyoid bone
Pharyngeal wall
Mandible
Deep lobe of parotid gland
Prevertebral fascia
The styloid process divides the space into:
Contains:
Fat
Deep lobe of parotid gland
Lymph nodes
Contains:
Internal carotid artery
Internal jugular vein
Cranial nerves IX, X, XI, XII
Sympathetic chain
ICA
IJV
CN IX
CN X
CN XI
CN XII
May arise from:
Tonsillar infection
Dental infection
Deep neck infections
Common tumors:
Pleomorphic adenoma
Schwannoma
Paraganglioma
Transcervical
Transparotid
Mandibulotomy approach
Prevertebral fascia
Vertebral bodies
Cervical vertebrae
Longus colli muscle
Longus capitis muscle
Deep neck musculature
Occurs in:
Tuberculosis of cervical spine
Vertebral osteomyelitis
Important landmark on:
CT scan
MRI
Insert Deep Neck Spaces Diagram
Showing:
Retropharyngeal space
Danger space
Parapharyngeal space
Prevertebral space
Carotid sheath
Waldeyer's ring is a circular arrangement of lymphoid tissue surrounding the entrance of the respiratory and digestive tracts.
Acts as the first immunological barrier against inhaled and ingested pathogens.
Develops from:
Mucosal-associated lymphoid tissue (MALT)
Endoderm-derived mucosa
Mesenchymal lymphoid infiltration
Development begins during fetal life and continues after birth.
Located:
Roof and posterior wall of nasopharynx
Located:
Around Eustachian tube openings
Located:
Tonsillar fossae of oropharynx
Largest clinically important tonsils.
Located:
Base of tongue
Present in:
Soft palate
Posterior pharyngeal wall
Lateral pharyngeal bands
Stratified squamous non-keratinized epithelium
Respiratory epithelium
Palatine tonsil:
10–20 deep crypts
Increase antigen exposure.
Contain:
Germinal centers
B lymphocytes
Plasma cells
Small lymphoid tissue
Rapid enlargement
Maximum development between 5–10 years
Begins involution
Progressive regression
Detects pathogens entering through:
Nose
Mouth
Especially:
Secretory IgA
Important for:
Mucosal immunity
Generation of:
B cells
T cells
Causes:
Mouth breathing
OME
Sleep-disordered breathing
Most common disease of Waldeyer's ring.
Due to adenotonsillar enlargement.
Usually:
Squamous cell carcinoma
Lymphoma
Insert Waldeyer's Ring Diagram
Showing:
Adenoid
Tubal tonsils
Palatine tonsils
Lingual tonsils
The pharynx receives a rich arterial supply from branches of the external carotid artery.
External carotid artery
Nasopharynx
Pharyngeal wall
Eustachian tube
Prevertebral muscles
Principal artery of the pharynx.
Supplies:
Soft palate
Tonsils
Oropharynx
Major blood supply to palatine tonsil.
Supply:
Base of tongue
Lingual tonsils
Oropharynx
Supplies:
Soft palate
Tonsillar region
Supplies:
Nasopharynx
Provide blood supply to:
Hypopharynx
Cricopharyngeal region
Located:
Outer surface of pharyngeal wall
Internal jugular vein
Facial vein
Pterygoid venous plexus
Major bleeding may arise from:
Tonsillar branch of facial artery
Peritonsillar venous plexus
Knowledge of vascular anatomy is essential for:
Pharyngectomy
Tumor resection
Free flap reconstruction
Insert Arterial Supply Diagram
Showing:
Ascending pharyngeal artery
Facial artery branches
Lingual artery branches
Maxillary artery branches
Superior thyroid artery branches
The pharynx has extensive lymphatic drainage, explaining the early nodal metastasis seen in pharyngeal malignancies.
Primarily to:
Retropharyngeal nodes
Upper deep cervical nodes
Especially:
Node of Rouvière
Nasopharyngeal carcinoma commonly presents with:
Cervical lymphadenopathy
Mainly to:
Jugulodigastric nodes
Upper deep cervical nodes
Tonsillar carcinoma frequently metastasizes early.
To:
Upper deep cervical nodes
Middle deep cervical nodes
Lower deep cervical nodes
Hypopharyngeal cancers have extensive nodal spread.
Behind pharynx.
Drain:
Nasopharynx
Posterior nasal cavity
Eustachian tube
Tonsillar nodes.
Palatine tonsils
Oropharynx
Drain:
Nasopharynx
Oropharynx
Drain:
Hypopharynx
Drain:
Distal hypopharynx
Nasopharynx
→ Retropharyngeal nodes
→ Upper deep cervical nodes
Tonsil
→ Jugulodigastric node
Pyriform fossa
→ Deep cervical nodes
First lymph node receiving lymphatic drainage from a primary lesion.
Used in:
Cancer staging
Metastasis prediction
Surgical planning
Insert Lymphatic Drainage Flowchart
Showing:
Nasopharynx
Oropharynx
Hypopharynx
Major lymph node groups
A neural network situated on the middle constrictor muscle.
Provides most motor and sensory innervation to the pharynx.
Derived from:
Pharyngeal branch of vagus nerve (CN X)
Provides:
Major motor supply
Derived from:
CN IX
Provides:
Sensory innervation
Derived from:
Superior cervical sympathetic ganglion
Provides:
Vasomotor fibers
Provides:
Tensor veli palatini motor supply
Sensory contribution to nasopharynx
Supplies:
Stylohyoid
Posterior belly of digastric
Indirect contribution to pharyngeal function.
Stylopharyngeus
Oropharynx
Tonsil
Posterior tongue
Major motor nerve of pharynx.
Supplies:
Constrictors
Palatopharyngeus
Salpingopharyngeus
Motor fibers join:
Vagus nerve
Contribute to pharyngeal plexus.
Supplies:
Tongue muscles
Essential for swallowing.
Supplied by:
Vagus nerve via pharyngeal plexus
Stylopharyngeus
→ CN IX
Tensor veli palatini
→ CN V3
| Region | Nerve |
|---|---|
| Nasopharynx | V2 |
| Oropharynx | CN IX |
| Hypopharynx | CN X |
Parasympathetic fibers supply:
Pharyngeal mucous glands
Mainly through:
Facial nerve pathways
Insert Pharyngeal Plexus Diagram
Showing:
CN IX
CN X
Sympathetic fibers
Pharyngeal plexus
Protective reflex preventing aspiration and pharyngeal injury.
Stimulus arises from:
Tonsillar region
Posterior pharyngeal wall
Produces:
Elevation of soft palate
Pharyngeal contraction
Absent gag reflex may indicate:
CN IX lesion
CN X lesion
Brainstem disease
Protects lower respiratory tract.
Internal laryngeal nerve.
Recurrent laryngeal nerve and respiratory muscles.
Triggered when food reaches:
Oropharynx
Produces:
Coordinated swallowing sequence
Touch:
Posterior pharyngeal wall
Observe:
Palatal elevation
Pharyngeal contraction
Observe:
Water swallowing
Coughing
Aspiration
Insert Reflex Arc Diagram
Showing:
Afferent pathways
Brainstem centers
Efferent pathways
The pharynx functions as a common pathway for respiration, deglutition, phonation, resonance, and immunity.
Air conduction
Air warming
Humidification
Filtration
Primarily performed by:
Nasopharynx
Food transport
Coordination of swallowing
Transfer of bolus into esophagus
Gag reflex
Cough reflex
Velopharyngeal closure
Laryngeal closure
Prevent:
Aspiration
Nasal regurgitation
Pharynx acts as a resonance chamber.
Influences:
Voice quality
Speech tone
Mainly through:
Waldeyer's ring
Provides:
Antigen detection
IgA production
Mucosal immunity
Swallowing (deglutition) is the coordinated process by which food and liquids are transported from the oral cavity to the stomach.
It involves voluntary and involuntary neuromuscular activities.
Swallowing is controlled by a complex brainstem network.
Located in:
Medulla oblongata
Coordinates:
Oral
Pharyngeal
Esophageal phases
Primary sensory nucleus.
Receives input from:
CN V
CN VII
CN IX
CN X
Primary motor nucleus.
Controls:
Pharyngeal muscles
Laryngeal muscles
Upper esophageal sphincter
Network of interneurons within medulla.
Coordinates sequential muscle activation during swallowing.
Mastication
Oral phase
Lip seal
Buccinator action
Sensory trigger for pharyngeal phase
Motor control of pharynx and larynx
Tongue movements
Swallowing consists of four phases.
Voluntary phase.
Food is chewed
Saliva mixed
Bolus formed
Voluntary phase.
Tongue presses bolus against palate
Bolus propelled posteriorly toward oropharynx
Involuntary phase.
Duration:
Approximately 1 second
Most critical phase for airway protection.
By:
Levator veli palatini
Tensor veli palatini
Closes nasopharynx and prevents nasal regurgitation.
Posterior pharyngeal wall moves forward.
Forms:
Passavant's ridge
Completes velopharyngeal closure.
Produced by:
Suprahyoid muscles
Longitudinal pharyngeal muscles
Protects airway and assists UES opening.
Adduct completely.
Also approximate.
Airway protection.
Arytenoids move forward.
Aryepiglottic folds approximate.
Further seals laryngeal inlet.
Epiglottis folds backward over laryngeal inlet.
Directs bolus toward pyriform fossae.
Cricopharyngeus relaxes.
Allows:
Bolus entry into esophagus
Sequential contraction of:
Superior constrictor
Middle constrictor
Inferior constrictor
Propels bolus into esophagus.
Involuntary phase.
Duration:
8–20 seconds
Moves bolus toward stomach.
Triggered if residual food remains.
Allows entry into stomach.
Insert Swallowing Physiology Flowchart
Food Bolus Formation
↓
Oral Propulsion
↓
Soft Palate Elevation
↓
Passavant Ridge Formation
↓
Laryngeal Elevation
↓
Vocal Cord Closure
↓
Aryepiglottic Closure
↓
Epiglottic Inversion
↓
UES Relaxation
↓
Pharyngeal Contraction
↓
Esophageal Peristalsis
↓
Stomach
Passavant's ridge is a transverse mucosal ridge formed on the posterior pharyngeal wall during swallowing and speech.
It forms due to forward movement of the posterior pharyngeal wall.
Mainly:
Palatopharyngeus
Superior constrictor
Salpingopharyngeus
Helps close the nasopharynx
Prevents nasal regurgitation
Assists speech resonance
During swallowing and speech:
Soft palate elevates
↓
Posterior pharyngeal wall moves forward
↓
Passavant's ridge forms
↓
Nasopharynx is closed off from oropharynx
Failure of closure causes:
Hypernasal speech
Nasal regurgitation
Weak oral pressure during speech
Passavant's ridge may become prominent as compensatory mechanism.
Deglutition apnoea is the temporary cessation of breathing during swallowing.
During swallowing:
Respiratory centre is briefly inhibited
Vocal cords close
Larynx elevates
Airway is protected
Usually lasts:
Less than 1 second
Food and liquid are prevented from entering the airway.
Normally swallowing occurs during expiration.
Poor coordination may cause:
Coughing during feeds
Aspiration
Recurrent pneumonia
Airway protection is essential because the pharynx is a common pathway for food and air.
True vocal cords adduct tightly.
First strong barrier against aspiration
False vocal cords also approximate.
Provides additional supraglottic protection
Arytenoids move forward and aryepiglottic folds close.
Narrows and protects laryngeal inlet
Epiglottis bends backwards over laryngeal inlet.
Deflects bolus laterally into pyriform fossae
Larynx moves upward and forward.
Pulls airway away from bolus path
Assists UES opening
If material enters larynx:
Cough reflex expels it
Main protective mechanisms:
Deglutition apnoea
Vocal cord closure
False cord closure
Aryepiglottic fold closure
Epiglottic inversion
Laryngeal elevation
Cough reflex
Insert Airway Protection Diagram
Showing:
Vocal cord closure
Epiglottic inversion
Laryngeal elevation
Bolus pathway
The pharynx acts as a resonating chamber for voice produced by the larynx.
Voice quality depends on:
Shape of pharynx
Position of soft palate
Oral cavity
Nasal cavity
Tongue position
Occurs when sound is directed mainly through oral cavity.
Important for:
Most speech sounds
Occurs when sound passes through nasal cavity.
Important for nasal consonants:
M
N
Ng
Normal speech uses both oral and nasal resonance in a balanced manner.
Closure between nasopharynx and oropharynx by elevation of soft palate against posterior pharyngeal wall.
Prevents air escape through nose during speech
Allows proper articulation
Failure of soft palate to close the nasopharynx properly.
Cleft palate
Post-adenoidectomy palatal insufficiency
Neuromuscular weakness
Short soft palate
Excessive nasal resonance during speech.
Incomplete velopharyngeal closure.
Cleft palate
Velopharyngeal insufficiency
Palatal paralysis
Reduced nasal resonance.
Nasal or nasopharyngeal obstruction.
Adenoid hypertrophy
Nasal polyps
Severe rhinitis
Nasopharyngeal mass
Mucosa-associated lymphoid tissue is lymphoid tissue present in mucosal surfaces.
Detects pathogens
Produces immune response
Protects respiratory and digestive tract entry
Nasal-associated lymphoid tissue is lymphoid tissue associated with nasal and nasopharyngeal mucosa.
Adenoid
Tonsils act as immune surveillance organs.
Trap antigens
Present antigens to lymphocytes
Produce antibodies
Generate memory immune response
Secretory IgA protects mucosal surfaces.
Neutralizes pathogens
Prevents microbial adhesion
Protects mucosa without intense inflammation
Antigens entering through mouth or nose are trapped by tonsillar crypts and lymphoid follicles.
Sequence:
Antigen exposure
↓
Uptake by epithelial cells/M cells
↓
Presentation to lymphocytes
↓
B-cell and T-cell activation
↓
Antibody production
Specialized epithelial cells that transport antigens from mucosal surface to lymphoid tissue.
Initiate mucosal immune response
Present antigen to immune cells
Germinal centres are active areas inside lymphoid follicles.
B-cell proliferation
Plasma cell formation
Antibody production
Memory cell formation
Tonsillar epithelium and lymphoid tissue are closely associated.
Efficient antigen capture
Immune surveillance
Local defense
Insert Tonsillar Immunology Diagram
Showing:
Crypt epithelium
M cells
Lymphoid follicles
Germinal centres
IgA production
During wakefulness:
Pharyngeal dilator muscles maintain airway patency
Important muscles:
Genioglossus
Tensor veli palatini
Palatoglossus
Pharyngeal constrictors
During sleep:
Muscle tone decreases
Airway becomes more collapsible
Collapse commonly occurs at:
Soft palate level
Retrolingual region
Lateral pharyngeal wall
Hypopharynx
Predisposing factors:
Obesity
Large tonsils
Large tongue base
Retrognathia
Reduced neuromuscular tone
Sequence:
Sleep
↓
Reduced pharyngeal muscle tone
↓
Upper airway narrowing/collapse
↓
Reduced airflow or obstruction
↓
Hypoxia and hypercapnia
↓
Arousal from sleep
↓
Airway reopens
↓
Cycle repeats
Snoring
Witnessed apnoea
Daytime sleepiness
Morning headache
Poor concentration
Common anatomical causes:
Adenotonsillar hypertrophy
Deviated nasal septum
Nasal obstruction
Large soft palate
Tongue base obstruction
Insert OSA Pathophysiology Flowchart
Showing:
Reduced tone
Airway collapse
Apnoea
Hypoxia
Arousal
FEES is an endoscopic assessment of swallowing using a flexible nasopharyngoscope.
Assesses pharyngeal phase of swallowing
Detects aspiration
Detects residue in vallecula or pyriform fossae
Evaluates vocal cord movement
Bedside test
No radiation
Direct view of pharynx and larynx
Useful in neurological dysphagia
Brief white-out during actual swallow
Oral and esophageal phases not assessed fully
A dynamic radiological study of swallowing using contrast material.
Also called:
Modified barium swallow
Assesses:
Oral phase
Pharyngeal phase
Esophageal phase
Aspiration
UES opening
Bolus transit
Dynamic real-time assessment
Shows bolus movement
Identifies silent aspiration
Radiation exposure
Requires patient cooperation
A pressure-based test measuring pharyngeal and upper esophageal sphincter pressures.
Assesses:
Pharyngeal contraction pressure
UES resting tone
UES relaxation
Coordination of swallowing
Useful in:
Cricopharyngeal achalasia
UES dysfunction
Neurogenic dysphagia
Endoscopic evaluation of pharynx and larynx using flexible fiberoptic scope.
Vocal cord assessment
Structural lesions
Pooling of saliva
Aspiration risk
Tumors
Neurological swallowing disorders
| Investigation | Main Use |
|---|---|
| FEES | Direct endoscopic swallowing assessment |
| Videofluoroscopy | Dynamic bolus transit study |
| High-resolution manometry | Pressure and UES function |
| Fiberoptic assessment | Structural and functional evaluation |
Adenoid lies on roof and posterior wall of nasopharynx.
Nasal obstruction
Mouth breathing
Snoring
Hyponasal speech
OME due to Eustachian tube obstruction
Eustachian tube opens into lateral wall of nasopharynx.
Adenoid hypertrophy
Nasopharyngeal inflammation
Tumor near torus tubarius
Ear blockage
Conductive hearing loss
OME
Recurrent otitis media
Retropharyngeal space contains lymph nodes in children.
Fever
Dysphagia
Neck stiffness
Bulge in posterior pharyngeal wall
Airway obstruction
Parapharyngeal space lies lateral to pharynx and communicates with other deep neck spaces.
Fever
Trismus
Medial bulge of tonsil/pharyngeal wall
Neck swelling
Occurs in peritonsillar space between tonsillar capsule and superior constrictor.
Severe sore throat
Trismus
Muffled voice
Uvula deviation
Medial displacement of tonsil
Fossa of Rosenmüller is a recess behind torus tubarius.
Commonest site of origin of nasopharyngeal carcinoma.
Unilateral OME in an adult should raise suspicion of NPC.
Pyriform fossa lies lateral to laryngeal inlet.
Fish bone
Internal laryngeal nerve lies beneath mucosa of pyriform fossa and may be injured.
Internal laryngeal nerve pierces thyrohyoid membrane and supplies supraglottic sensation.
Loss of supraglottic sensation
Aspiration risk
Impaired cough reflex
Cricopharyngeus forms main part of upper esophageal sphincter.
Dysphagia
Globus sensation
Difficulty initiating swallow
A pulsion diverticulum arising through Killian's dehiscence.
Between:
Thyropharyngeus
Cricopharyngeus
Dysphagia
Regurgitation of undigested food
Halitosis
Aspiration
Neck gurgling
A mucosal herniation through a weak area of pharyngeal wall, commonly Killian's dehiscence.
Commonly refers to:
Zenker diverticulum
Difficulty in swallowing.
Tonsillar enlargement
Tumors
Neurological weakness
Cricopharyngeal dysfunction
Foreign body
Pharyngeal pouch
Sensation of lump in throat without true obstruction.
Reflux
Anxiety
Cricopharyngeal spasm
Pharyngeal irritation
Failure of soft palate to close nasopharynx during speech or swallowing.
Hypernasal speech
Nasal regurgitation
Weak speech pressure
Collapse of pharyngeal airway during sleep.
Adenotonsillar hypertrophy
Large soft palate
Tongue base obstruction
Nasal obstruction
Fossa of Rosenmüller
Neck node
Nasal obstruction
Epistaxis
Unilateral OME
Cranial nerve palsy
Tonsil
Base of tongue
Soft palate
Sore throat
Dysphagia
Referred otalgia
Neck node
Pyriform fossa
Dysphagia
Odynophagia
Referred otalgia
Hoarseness
Neck node
| Condition | Anatomical Basis | Key Clinical Point |
|---|---|---|
| Adenoid hypertrophy | Nasopharyngeal lymphoid tissue | Nasal obstruction, OME |
| ET dysfunction | ET opening near adenoid | OME |
| Retropharyngeal abscess | Retropharyngeal nodes | Airway risk |
| Peritonsillar abscess | Peritonsillar space | Uvula deviation |
| NPC | Fossa of Rosenmüller | Adult unilateral OME |
| Fish bone | Pyriform fossa | ILN injury risk |
| Zenker diverticulum | Killian's dehiscence | Regurgitation, halitosis |
| OSA | Pharyngeal collapse | Snoring, apnoea |
| Hypopharyngeal carcinoma | Pyriform fossa | Early nodal spread |
Zenker diverticulum (Pharyngeal pouch) is a pulsion diverticulum arising through a weak area in the posterior wall of the hypopharynx known as Killian's dehiscence, located between the inferior constrictor and cricopharyngeus muscles.
It is an outpouching of the mucosa and submucosa through a weak area above the upper esophageal sphincter due to increased swallowing pressure.
Most common pharyngoesophageal diverticulum.
Usually occurs in elderly individuals (>50 years).
More common in males.
Considered a false diverticulum because it lacks all layers of the wall.
Zenker diverticulum develops due to a combination of:
Presence of Killian's dehiscence, a natural muscular gap in the posterior hypopharyngeal wall.
Failure of cricopharyngeus muscle to relax during swallowing.
Causes increased intrapharyngeal pressure.
Repeated pressure forces mucosa and submucosa through Killian's dehiscence.
Degeneration and fibrosis of cricopharyngeus muscle.
Reduced compliance of upper esophageal sphincter.
Swallowing dysfunction
↓
Cricopharyngeal spasm/non-relaxation
↓
Raised hypopharyngeal pressure
↓
Herniation through Killian's dehiscence
↓
Formation of diverticulum
↓
Progressive enlargement
A triangular area of muscular weakness in the posterior wall of the pharyngoesophageal junction.
| Structure | Boundary |
|---|---|
| Above | Oblique fibers of thyropharyngeus (inferior constrictor) |
| Below | Transverse fibers of cricopharyngeus muscle |
Site of origin of Zenker diverticulum.
Weakest area in hypopharynx.
Subjected to high intraluminal pressure during swallowing.
Killian's Dehiscence
Continue with Google
Inferior Constrictor
(Thyropharyngeus)
\\\\\\\\\\\\\\\\
Killian's
Dehiscence
----------------
Cricopharyngeus
----------------
Esophagus
Sac-like protrusion from posterior hypopharyngeal wall.
Usually projects towards left side of neck.
May vary from a few millimeters to several centimeters.
Can retain food, mucus and secretions.
A false diverticulum consisting of:
Mucosa
Submucosa
Absent:
Muscular layer
Large pouches may contain:
Food debris
Mucus
Saliva
Retained tablets
Foreign bodies
Chronic inflammation
Ulceration
Infection
Fibrosis
Rare malignant transformation
Usually seen in elderly patients.
Progressive
Initially for solids
Later for liquids
Characteristic symptom.
Food eaten hours earlier may be regurgitated.
Particularly when lying down.
Due to decomposition of retained food.
Patient may notice:
Splashing sensation
Gurgling sounds
Caused by aspiration of pouch contents.
Especially during sleep.
Due to recurrent aspiration.
Secondary to dysphagia.
Occasionally:
Soft swelling in lower neck.
Compressible.
May produce gurgling on pressure.
Hoarseness
Wet or gurgling voice
| Feature | Description |
|---|---|
| Dysphagia | Progressive swallowing difficulty |
| Regurgitation | Undigested food |
| Halitosis | Foul breath |
CBC
Renal function tests
Blood sugar
Fitness for anesthesia
Barium swallow (Investigation of choice)
Endoscopy
CT scan (selected cases)
Contrast-filled posterior sac.
Arises at pharyngoesophageal junction.
Communicates with esophageal lumen.
Demonstrates:
Size
Shape
Neck of pouch
Retention of contrast
Confirms diagnosis.
Determines size of pouch.
Helps surgical planning.
Detects aspiration.
Hypopharynx
|
|
( )
( ) ← Diverticulum
( )
|
|
Esophagus
Barium swallow showing Zenker diverticulum arising posteriorly from pharyngoesophageal junction.
Performed after radiological diagnosis.
Pouch opening visualized.
Retained food particles.
Pooling of secretions.
Inflammation or ulceration.
Direct visualization.
Excludes malignancy.
Useful before endoscopic surgery.
Blind endoscopy may:
Enter diverticulum instead of esophagus.
Cause perforation.
Hence:
Barium swallow should precede endoscopy.
Definitive treatment requires:
AND
Symptomatic diverticulum
Dysphagia
Aspiration
Regurgitation
Recurrent chest infection
Weight loss
Traditionally regarded as definitive treatment.
Most important step.
Relieves functional obstruction.
Prevents recurrence.
Complete excision of pouch.
Pouch suspended superiorly.
Pouch inverted into lumen.
Left cervical incision.
Identify diverticulum.
Perform cricopharyngeal myotomy.
Excise or suspend pouch.
Closure.
Suitable for large diverticula.
Complete removal possible.
Histopathological examination available.
External neck incision.
Longer hospital stay.
Higher morbidity.
Endoscopic division of common wall between:
Esophagus
Diverticulum
using a surgical stapler.
Common septum contains:
Cricopharyngeus muscle
Division causes:
Myotomy
Communication of pouch with esophagus
Food passes directly into esophagus.
Minimally invasive.
Short operative time.
Early oral feeding.
Short hospital stay.
Less postoperative pain.
Difficult in very small pouch.
Not suitable in limited neck extension.
Recurrence possible.
Before Stapling
Esophagus | Diverticulum
After Stapling
Single common channel
Common wall between pouch and esophagus is divided using:
CO₂ laser
Other endoscopic laser systems
Septum divided under microscopic visualization.
Cricopharyngeal fibers cut.
Common cavity created.
Excellent precision.
Minimal bleeding.
Faster recovery.
No external scar.
Requires expertise.
Risk of mediastinal emphysema.
Risk of perforation.
Most important complication.
Rare (<1%).
Hemorrhage
Neck infection
Pharyngocutaneous fistula
Recurrent laryngeal nerve injury
Esophageal perforation
Mediastinitis
Recurrence
Persistent dysphagia
Stricture formation
Residual pouch
Q. What is Zenker diverticulum?
A pulsion false diverticulum arising through Killian's dehiscence above the cricopharyngeus muscle.
Q. What is Killian's dehiscence?
A muscular gap between thyropharyngeus and cricopharyngeus fibers.
Q. Is Zenker diverticulum a true or false diverticulum?
False diverticulum.
Q. Investigation of choice?
Barium swallow.
Q. Most important step in treatment?
Cricopharyngeal myotomy.
Q. Most common symptom?
Progressive dysphagia.
Q. Most important complication?
Aspiration pneumonia.
| Feature | Zenker Diverticulum |
|---|---|
| Type | False pulsion diverticulum |
| Site | Killian's dehiscence |
| Age | Elderly |
| Cause | Cricopharyngeal dysfunction |
| Most common symptom | Dysphagia |
| Classical feature | Regurgitation of undigested food |
| Investigation of choice | Barium swallow |
| Definitive treatment | Cricopharyngeal myotomy + pouch treatment |
| Common modern surgery | Endoscopic stapling |
| Important complication | Aspiration pneumonia |
| Rare complication |
Squamous cell carcinoma |
| Feature | Description |
|---|---|
| Definition | Fibromuscular tube connecting nasal and oral cavities to larynx and esophagus |
| Extent | Base of skull to lower border of cricoid cartilage (C6) |
| Length | Approximately 12–14 cm |
| Shape | Funnel-shaped |
| Parts | Nasopharynx, Oropharynx, Hypopharynx |
| Function | Respiration, deglutition, phonation, resonance, immunity |
| Embryology | Derived from primitive foregut and pharyngeal apparatus |
| Arch | Nerve | Muscle Derivatives | Skeletal Derivatives |
|---|---|---|---|
| 1st | CN V3 | Muscles of mastication | Maxilla, mandible, malleus, incus |
| 2nd | CN VII | Muscles of facial expression | Stapes, styloid process |
| 3rd | CN IX | Stylopharyngeus | Greater horn of hyoid |
| 4th | CN X (Superior laryngeal) | Cricothyroid, pharyngeal constrictors | Laryngeal cartilages |
| 6th | CN X (Recurrent laryngeal) | Intrinsic laryngeal muscles | Laryngeal cartilages |
| Pouch | Derivatives |
|---|---|
| 1st | Eustachian tube, middle ear cavity |
| 2nd | Palatine tonsil |
| 3rd | Inferior parathyroid, thymus |
| 4th | Superior parathyroid |
| 5th (ultimobranchial body) | Parafollicular (C) cells of thyroid |
| Anomaly | Description |
|---|---|
| Branchial cyst | Persistent branchial apparatus remnant |
| Branchial sinus | Blind-ending tract |
| Branchial fistula | Communication between skin and pharynx |
| Cleft palate | Failure of palatal fusion |
| Choanal atresia | Failure of posterior nasal aperture formation |
| Velopharyngeal insufficiency | Inadequate closure during speech |
| Feature | Description |
|---|---|
| Extent | Base of skull to soft palate |
| Epithelium | Pseudostratified ciliated columnar |
| Openings | Eustachian tube openings |
| Important Structures | Fossa of Rosenmüller, adenoids |
| Function | Respiration and middle ear ventilation |
| Feature | Description |
|---|---|
| Extent | Soft palate to upper border of epiglottis |
| Epithelium | Stratified squamous |
| Components | Tonsils, base of tongue, soft palate |
| Function | Common pathway for food and air |
| Feature | Description |
|---|---|
| Extent | Upper epiglottis to lower border of cricoid cartilage |
| Components | Pyriform sinus, posterior pharyngeal wall, postcricoid region |
| Clinical Importance | Common site for carcinoma and foreign body impaction |
| Feature | Nasopharynx | Oropharynx | Hypopharynx |
|---|---|---|---|
| Epithelium | Respiratory | Squamous | Squamous |
| Function | Respiration | Air + food | Air + food |
| Tonsils | Adenoids | Palatine tonsils | None |
| Tumors | NPC | OPSCC | Hypopharyngeal SCC |
| Region | Epithelium |
|---|---|
| Nasopharynx | Pseudostratified ciliated columnar |
| Oropharynx | Stratified squamous non-keratinized |
| Hypopharynx | Stratified squamous non-keratinized |
| Muscle | Origin | Insertion |
|---|---|---|
| Superior constrictor | Pterygomandibular raphe | Median raphe |
| Middle constrictor | Hyoid bone | Median raphe |
| Inferior constrictor | Thyroid and cricoid cartilage | Median raphe |
Function: Propel food downward.
| Muscle | Nerve Supply | Function |
|---|---|---|
| Stylopharyngeus | CN IX | Elevates pharynx |
| Palatopharyngeus | CN X | Elevates pharynx |
| Salpingopharyngeus | CN X | Elevates pharynx |
| Feature | Cricopharyngeus | Thyropharyngeus |
|---|---|---|
| Fiber Direction | Horizontal | Oblique |
| Function | UES sphincter | Constrictor |
| Relaxation | During swallowing | Contracts during swallowing |
| Clinical Importance | Zenker diverticulum | Upper boundary of Killian dehiscence |
| Feature | Description |
|---|---|
| Main Muscle | Cricopharyngeus |
| Level | C5–C6 |
| Resting State | Tonically contracted |
| During Swallowing | Relaxes |
| Function | Prevents air entry and reflux |
| Feature | Killian Dehiscence | Laimer Triangle | Killian-Jamieson Area |
|---|---|---|---|
| Location | Between thyropharyngeus and cricopharyngeus | Below cricopharyngeus | Lateral to cricopharyngeus |
| Diverticulum | Zenker | Laimer diverticulum | Killian-Jamieson diverticulum |
| Frequency | Common | Rare | Rare |
| Space | Boundaries | Clinical Importance |
|---|---|---|
| Retropharyngeal | Behind pharynx | Abscess |
| Parapharyngeal | Lateral pharynx | Deep neck infection |
| Danger space | Behind retropharyngeal space | Mediastinal spread |
| Feature | Retropharyngeal | Parapharyngeal |
|---|---|---|
| Age | Children | Adults |
| Neck Swelling | Usually absent | Present |
| Trismus | Rare | Common |
| Airway Obstruction | Common | Less common |
| Cause | LN infection | Tonsillar infection |
| Component | Location |
|---|---|
| Pharyngeal tonsil | Nasopharynx |
| Tubal tonsils | Eustachian tube opening |
| Palatine tonsils | Oropharynx |
| Lingual tonsils | Base of tongue |
| Artery | Source |
|---|---|
| Ascending pharyngeal | External carotid |
| Facial artery branches | External carotid |
| Lingual artery branches | External carotid |
| Maxillary artery branches | External carotid |
| Region | Main Nodes |
|---|---|
| Nasopharynx | Retropharyngeal, upper deep cervical |
| Oropharynx | Jugulodigastric |
| Hypopharynx | Deep cervical chain |
| Component | Contribution |
|---|---|
| Motor | CN X |
| Sensory | CN IX |
| Sympathetic | Superior cervical ganglion |
| Nerve | Function |
|---|---|
| CN V | Tensor veli palatini |
| CN IX | Sensory pharynx, stylopharyngeus |
| CN X | Motor pharynx |
| CN XI | Joins vagus fibers |
| CN XII | Tongue movement |
| Component | Nerve |
|---|---|
| Afferent limb | CN IX |
| Efferent limb | CN X |
| Center | Medulla |
| Phase | Control |
|---|---|
| Oral preparatory | Voluntary |
| Oral propulsive | Voluntary |
| Pharyngeal | Involuntary |
| Esophageal | Involuntary |
| Event | Purpose |
|---|---|
| Soft palate elevation | Prevent nasal regurgitation |
| Laryngeal elevation | Airway protection |
| Vocal cord closure | Prevent aspiration |
| Epiglottic tilt | Airway protection |
| UES relaxation | Food entry into esophagus |
| Mechanism | Function |
|---|---|
| Vocal fold closure | Prevent aspiration |
| False cord closure | Secondary barrier |
| Epiglottic closure | Deflects bolus |
| Cough reflex | Clears aspirate |
| Laryngeal elevation | Protects airway |
| Feature | Description |
|---|---|
| Definition | Mucosal ridge on posterior pharyngeal wall |
| Muscle | Palatopharyngeus contribution |
| Function | Velopharyngeal closure during speech |
| Disorder | Cause |
|---|---|
| Velopharyngeal insufficiency | Structural defect |
| Velopharyngeal incompetence | Neuromuscular disorder |
| Submucous cleft palate | Congenital |
| Recess | Clinical Importance |
|---|---|
| Fossa of Rosenmüller | Commonest site of NPC |
| Tubal recess | Around Eustachian tube |
| Feature | Pediatric | Adult |
|---|---|---|
| Adenoids | Prominent | Regressed |
| Retropharyngeal nodes | Present | Absent |
| Airway | Narrow | Wider |
| Infection | Common | Less common |
| Feature | Normal Sleep | OSA |
|---|---|---|
| Airway | Patent | Collapsible |
| Oxygen saturation | Normal | Reduced |
| Snoring | Mild/absent | Common |
| Daytime somnolence | Absent | Present |
| Feature | FEES | VFSS | Manometry |
|---|---|---|---|
| Direct visualization | Yes | No | No |
| Aspiration detection | Excellent | Excellent | Limited |
| Radiation | No | Yes | No |
| Pressure assessment | No | No | Yes |
| Site | Importance |
|---|---|
| Tonsil | Common |
| Base of tongue | Common |
| Vallecula | Common |
| Pyriform sinus | Most common hypopharyngeal site |
| Cricopharynx | Common esophageal site |
| Symptom | Probable Site |
|---|---|
| Nasal regurgitation | Soft palate |
| Aspiration | Pharynx/larynx |
| Food sticking in neck | Cervical esophagus |
| Progressive dysphagia | Tumor |
| Site | Common Spread |
|---|---|
| Nasopharynx | Retropharyngeal nodes |
| Tonsil | Jugulodigastric nodes |
| Base of tongue | Bilateral cervical nodes |
| Pyriform sinus | Deep cervical nodes |
| Structure | Surgical Importance |
|---|---|
| Killian dehiscence | Zenker diverticulum |
| Rosenmüller fossa | Nasopharyngeal carcinoma |
| Pyriform sinus | Foreign body, carcinoma |
| Retropharyngeal space | Abscess |
| Cricopharyngeus | UES surgery |
| Internal carotid artery | Parapharyngeal surgery |
| Recurrent laryngeal nerve | Thyroid and hypopharyngeal surgery |
| Superior laryngeal nerve | Pharyngeal and laryngeal procedures |
| Question | Answer |
|---|---|
| Most common site of NPC | Fossa of Rosenmüller |
| Afferent limb of gag reflex | CN IX |
| Efferent limb of gag reflex | CN X |
| Main UES muscle | Cricopharyngeus |
| Commonest site of hypopharyngeal carcinoma | Pyriform sinus |
| Site of Zenker diverticulum | Killian dehiscence |
| Commonest cervical node for tonsil carcinoma | Jugulodigastric node |
| Commonest deep neck abscess in children | Retropharyngeal abscess |
| Investigation of choice for swallowing disorders | VFSS (modified barium swallow) |
| Gold standard for Zenker diverticulum | Barium swallow |
NASOPHARYNX
______________________
↑ Soft palate
/\
/ \
/ \
/ \_____
\
\
--------------------------●-------------------
Passavant Ridge
(Posterior pharyngeal wall)
OROPHARYNX
Soft palate
Passavant ridge
Posterior pharyngeal wall
Nasopharynx
Oropharynx
NASOPHARYNX
____________________
│
│
│
< PHARYNGEAL >
< ISTHMUS >
┌────────────┐
│ Soft palate│
└────────────┘
│
│
OROPHARYNX
Nasopharynx
Soft palate
Pharyngeal isthmus
Oropharynx
Inferior Constrictor
(Thyropharyngeus)
\\\\\\\\\\\\\
KILLIAN'S
DEHISCENCE
▲
▲
▲
========================
Cricopharyngeus
========================
Esophagus
Thyropharyngeus
Cricopharyngeus
Killian dehiscence
========================
Cricopharyngeus
========================
▼
▼
LAIMER TRIANGLE
------------------------
Circular Esophageal
Fibers
------------------------
Cricopharyngeus
Laimer triangle
Esophagus
Cricopharyngeus
==============================
▲ ▲
│ │
Killian- Killian-
Jamieson Jamieson
Area Area
==============================
Cervical Esophagus
RLN RLN
Killian-Jamieson area
Recurrent laryngeal nerve
Cricopharyngeus
Hypopharynx
│
│
----------------
Cricopharyngeus
----------------
UES
│
│
Esophagus
Hypopharynx
Cricopharyngeus
UES
Esophagus
Cerebral Cortex
│
▼
Swallowing Centre
(Medulla)
┌────────┼────────┐
│ │ │
CN V CN IX CN X
│ │ │
CN XII
▼
Pharyngeal Muscles
Cerebral cortex
Medulla
CN V
CN IX
CN X
CN XII
ORAL PHASE
▼
[ Mouth ]
▼
PHARYNGEAL PHASE
▼
[ Pharynx ]
▼
ESOPHAGEAL PHASE
▼
[ Esophagus ]
▼
Stomach
Oral phase
Pharyngeal phase
Esophageal phase
Tongue
│
Epiglottis
\/
--------------
Laryngeal Inlet
--------------
False Cords
===========
True Cords
===========
Epiglottic closure
Arytenoid approximation
False cord closure
True cord closure
Cough reflex
NORMAL
Soft Palate
│
│
OPEN
AIRWAY
OSA
Soft Palate
▼
COLLAPSED
AIRWAY
Tongue Base
▲
Soft palate
Tongue base
Airway collapse
Nasopharynx
__________________
Torus Tubarius
○
│
│
Eustachian Tube
│
Fossa of Rosenmüller
│
Adenoids
Torus tubarius
Eustachian tube opening
Fossa of Rosenmüller
Adenoids
Aryepiglottic Fold
/ \
Pyriform Pyriform
Fossa Fossa
\ /
Laryngeal
Inlet
Pyriform fossa
Aryepiglottic fold
Laryngeal inlet
Superior Laryngeal
Nerve
│
▼
Internal Laryngeal
Nerve
│
▼
Thyrohyoid Membrane
│
▼
Pyriform Fossa
Superior laryngeal nerve
Internal laryngeal nerve
Thyrohyoid membrane
Pyriform fossa
CHILD
Large Adenoids
Large Tonsils
↓
ADULT
Moderate Adenoids
Moderate Tonsils
↓
ELDERLY
Atrophic Adenoids
Small Tonsils
Adenoids
Palatine tonsils
Lingual tonsils
Thyropharyngeus
\\\\\\\\\\\\\\\\\
=====================
Cricopharyngeus
=====================
Esophagus
Increased Pressure
↓
Thyropharyngeus
\\\\\\\\\\\\\\\\\
KILLIAN AREA
▲
▲
=====================
Cricopharyngeus
=====================
Hypopharynx
│
( )
( )
( Zenker )
(Divertic. )
( )
│
=====================
Cricopharyngeus
=====================
│
Esophagus
MedMentor EDU Note: These images should be inserted as high-resolution clinical photographs, endoscopic images, radiological images, or operative images. They are frequently asked in MBBS, MS ENT, DNB ENT, NEET-PG, INI-CET, FMGE, and viva examinations.
Uvula
Soft palate
Anterior pillar
Posterior pillar
Palatine tonsil
Posterior pharyngeal wall
Normal appearance of the oropharynx during oral examination.
Torus tubarius
Eustachian tube opening
Fossa of Rosenmüller
Posterior nasopharyngeal wall
Enlarged adenoid tissue
Choanal narrowing
Obstruction of nasopharyngeal airway
Most common image-based question in pediatric ENT.
Narrowed/obliterated choana
Obstructed posterior nasal airway
Retracted tympanic membrane
Air-fluid level
Glue ear changes
Enlarged tonsils
Reduced oropharyngeal airway
Uvular deviation
Soft palate bulge
Tonsillar displacement
Posterior pharyngeal wall swelling
Airway narrowing
Lateral pharyngeal wall bulge
Neck swelling
Trismus
Fish bone lodged in pyriform sinus.
Posterior indentation at C5–C6 level.
Contrast-filled posterior sac arising above UES.
Very high-yield exam image.
Pooling
Aspiration
Residue assessment
Oral phase
Pharyngeal phase
Aspiration events
Mass arising near fossa of Rosenmüller.
Commonest site of nasopharyngeal carcinoma.
Tonsil
Base of tongue
Pyriform sinus.
Nasopharynx
Oropharynx
Hypopharynx
Larynx
Soft palate collapse
Tongue base collapse
Lateral pharyngeal wall collapse
Adenoid hypertrophy
Tonsillar hypertrophy
Peritonsillar abscess
Retropharyngeal abscess
Foreign body in pyriform fossa
Cricopharyngeal bar
Zenker diverticulum (barium swallow)
FEES
VFSS
Nasopharyngeal carcinoma
Fossa of Rosenmüller lesion
Oropharyngeal carcinoma
Hypopharyngeal carcinoma
Flexible nasopharyngolaryngoscopy
OSA airway endoscopy
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