Branchial cleft cyst

Section: Head and neck Curriculum: Curriculum, page 43

Definition

• Failure of obliteration of branchial clefts 1-4

Epidemiology


• Late childhood

• Pharyngeal Arches, Pouch and Cleft

Aetiology


• Remnant of branchial cleft

• Incomplete involution of the pharyngeal cleft


Pathophysiology 


• Lead to:

  • Cyst, fistula, sinus

• Can become infected


Clinical


• Lateral swelling in the neck, anterior to SCM

• Swallowing or airway difficulties

• +/- fistula or sinus

• Will not move on swallowing

• Pharyngeal oedema - airway and swallowing difficulties

• Locations
  • 1st
    • Smooth, tender, non-fluctuant mass between ear canal and submandibular area
    • Cutaneous punctum that fluid can be expressed through
    • Can involve parotid, facial N and ear canal
  • 2nd
    • Punctum lower ant border SCM
    • Connect to tonsil fossa
    • Related to carotids (between) and CN 9/12 - superficial
    • Can cause AW compromise
  • 3rd/4th
    • Left neck, suprasternal notch/clavicular area
    • Firm masses are more likely recurrent infection related

Locations

1st - angle of mandible or within submandibular region 2nd - ant/med to SCM 3rd - middle/lower ⅓ ant SCM (punctum) 4th - middle/lower ⅓ ant SCM (punctum)

Classification 


• Based on their internal opening due to their Pharyngeal cleft of origin


• Classified 


  • First - External Auditory canal 

    • Course high 

    • With fistula through the parotid / Periauricular

    • Lateral to facial nerve 

  • Second - Tonsillar fossa

    • Exist along the anterior boarder of SCM 

    • Fistula through the platysma and ascent along carotid sheath

    • Passing between Internal Carotid and External Carotid Arteries

    • Caution CN IX, X, XI

    • Most common

  • Third - Pyriform Sinus

    • Lower in neck Anterior to SCM

    • Posterior to the Internal Carotid Artery

  • Fourth - Apex of Pyriform Sinus

    • Rare and do not fistulate


• Recurrent infections 


  • Can cause Fistulas


Investigations

• USS - confirm cystic nature
• OGD/flexible nasendoscopy if suspect fistula
• CT - localise tract and plan surgery
• Sinogram - to visualise tract

Management


• Medical
  • Abx +/- local drainage for recurrent infection
  • Minimal malignancy risk
• Surgery
  • Excision of branchial cyst

Summary

• Congenital epithelial cysts
  • Develop due to INCOMPLETE INVOLUTION OF BRANCHIAL CLEFT STRUCTURES
• 4 types correlating to 4 clefts
  • Cleft 2 is the most common
• Minimal malignancy risk
• Can cause cyst formation, sinus and fistula with recurrent infection
• Cleft 2 cyst has a punctum at the skin ant to SCM midpoint
• Track heads deep to platysma, between carotid bifurcation and superficial to CN 9 and 12 to reach the tonsillar fossa
• Dx is clinical with further characterization by cross sectional imaging and sinograph
• Mx includes abx for infection and definite surgical fistula tract ligation and division