Approach to head and neck

Location is Key to Diagnosis

Pharynx

• Tube from skull base to thoracic inlet, mucosal lined, squamous cell carcinoma most common tumor
• Includes nasopharynx, oropharyxn, oral cavity, hypopharynx (hyoid to esophagus), larynx

Anterior

• Masticator space - mandible and muscles of mastication, CN V3. Pathology includes abscess (dental), osseous (primary like Ewings or metastasis) and rhabdomyosarcoma
• Parotid space - salivary tissue (), lymph nodes, CN VII
  • Pleomorphic adenoma - most common mass, benign, mild peripheral enhancement, T2 bright
  • Parotid carcinoma
• Carotid space - artery (carotid body tumor intense enhancement), vein, CN IX-XII (schwannoma which enhances, neurofibroma (may not enhance as others))
• Parapharyngeal space - contains fat, used to identify masses in other compartments, because of displacement

Posterior

• Perivertebral space - most pathology originates in bone or disc
• Retropharyngeal space - potential space containing fat and lymph nodes
• Posterior cervical space - lateral to paraspinal muscles, contains lymph nodes and fat (level 5A and 5B)
  • Cystic hygroma - unilocular lymphatic malformation

Lymphatic and vascular malformations can cross facial planes because congenital (developed before planes). Otherwise, if cross spaces usualy aggressive.