Applied Anatomy

Post nasal space tumors

• Occur in nasopharynx
  
  
• Among commonest head and neck tumors
  
  
• Usually start from the pharyngeal recess
  
  
• Block choane and present with breathing difficulty
  
  
• Compress the lower cranial nerves
  
  
• Present with difficulty in swallowing (dysphagia) and dysphonia

Adenoids

• These are enlarged pharyngeal tonsils
  
  
• Common in children
  
  
• Obstruct choane
  
  
• Impair nasal breathing
  
  
• Block eustachean tube and cause giddiness

Tonsillitis

• Inflammation of the palatine tonsils
  
  
• A common ENT problem
  
  
• Pain often referred to the ear because of common innervation by glossopharyngeal nerve
  
  
• Present with pain and difficulty in swallowing
  
  
• Causes inflammation of submandibular and especially jugulo-digastric (tonsillar) nodes

Killihans Dehiscence

• A weak part between the thyropharyngeus and the cricopharyngeus (considered by others to exist between the inferior constrictor and esophagus).
  
  
• Pharyngeal mucosa can herniate through this part and enlarge to form a pharyngeal diverticulum
  .
• The pouches or diverticulae are impotant clinically because:

               (+) Food particles can lodge here
               (+) Gastroscope can enter and perforate.

Piriform Recess

• A recess in the lateral aspect of laryngo-pharynx
  
  
• Foreign bodies e.g. fish bones, pea nuts can lodge there.
  
  
• Favourite hiding place for tumours.
  
  
• Internal laryngeal nerve in the wall can be injured.

Cancer of the tongue

• Commonly spreads via lymphatics and hence the importance of studying the pattern of lymphatic drainage

Palate

• The mucosa is tightly adherent to bone therefore 'pimples' are very painful
  
  
• A site of congenital malformations - cleft palate

Swallowing problems

• These can arise from
  
  a) Local problems in the food passages - pharynx and esophagus
  
  b) Adjacent areas/ structures e.g. enlarged thyroid, retropharyngeal abscess and tumors
  
  c) Damage to cranial nerves: 9,10, 12
  
  d) Brain stem lesions

Anatomical spaces delineated by fascial planes represent potential vertical highways for spread of pathological processes

Pharyngeal mucosal space

• Located superficially along pharyngeal mucosal walls
• Includes mucosa of pharynx, waldeyers ring, cartilaginous Eustachian tube. Pharyngobasilar fascia, levator and constrictor muscles
• Represents superficial layer in which tumors often develop before they spread to deeper structures

Parapharyngeal space

• Extends from skull base to hyoid bone
• Contains fat, branches of trigeminal nerves and pterygoid veins
• Tumors in this space spread very rapidly

Carotid space

• Major vertical highway
• Extends from skull base to aortic arch
• Contains carotid arteries, internal jugular vein, cranial nerves 9-11 and deep cervical nodes
• Encasement of carotid arteries may tender tumors inoperable

Retropharyngeal space

• Potential midline space
• Extends from skull base to T3

Nasopharyngeal carcinoma

• Arises from the fossa of Rossen Mueller
• Presents with unilateral otitis media or mastoiditis
• Spreads along spinal accessory chain of nodes in posterior triangle of neck

Symptoms