• Clinical science

Congenital neck masses

Abstract

Congenital neck masses are developmental anomalies typically seen in infants or children. Common conditions include thyroglossal duct cysts, branchial cleft cysts, and cystic hygromas. These malformations present as painless neck masses, which can cause dysphagia, respiratory distress, and neck pain due to compression of surrounding structures. The location of the mass depends on the embryological structure the cysts arise from. Diagnosis is made based on clinical findings and imaging results (ultrasound, CT, MRI), which also help in surgical planning. Treatment consists of complete surgical resection to prevent recurrence and complications such as infection or abscess formation.

Thyroglossal duct cyst

  • Definition: a remnant of the thyroglossal duct that forms during the embryonic development of the thyroid gland
  • Epidemiology
  • Pathophysiology
  • Clinical features
    • The cyst is present from birth and usually detected during early childhood.
    • Painless, firm midline neck mass, usually near the hyoid bone, which elevates with swallowing and tongue protrusion
    • May cause dysphagia or neck/throat pain if the cyst enlarges
  • Diagnosis
    • Neck and thyroid examination
    • Ultrasound of the neck to evaluate the cyst and confirm location of the thyroid
    • Screen TSH levels
    • If an infection is suspected, perform fine needle biopsy for Gram stain and culture (including AFB and mycobacterial culture).
  • Treatment
    • Elective surgical excision (Sistrunk procedure) to prevent infection
    • Treatment of any active infection with antibiotics before surgery
  • Complications
    • Infection of the cyst with possible abscess formation
    • Sinus tract formation extends to the skin with persistent drainage
    • Possible ectopic thyroid tissue
    • Possible malignancy arising from ectopic thyroid tissue

Thyroglossal duct cysts will present in a child as a painless, firm, midline neck mass that moves with swallowing and tongue movement.

References:[1][2][3][4][5]

Branchial cleft cyst

  • Definition: remnants of the embryological second branchial cleft or cervical sinus
  • Epidemiology
  • Pathophysiology
  • Clinical features
    • Usually diagnosed in late childhood/adulthood after previously undiagnosed cyst becomes infected
    • Often a history of preceding upper respiratory infection
    • Painless, firm mass lateral to midline, usually anterior to the sternocleidomastoid muscle, which does not move with swallowing
    • Small draining opening may be present if fistula is present.
  • Diagnosis
    • Neck examination
    • Ultrasound
    • CT or MRI to further assess anatomical structures for surgical planning.
  • Treatment: : complete surgical excision of both the cyst and any associated tracts
  • Complication: s: infection of the cyst, tract, or sinus with possible abscess formation

Branchial cleft cysts will present in a child as a painless, firm neck mass lateral to the midline.

References:[4][5][6][7]

Cystic hygroma

  • Definition: congenital malformation consisting of cyst-like cavities containing lymph
  • Epidemiology
  • Clinical features
    • Soft, compressible, painless neck mass
    • Classically found in the posterior triangle of the neck
    • Can cause dysphagia or airway compromise
    • Can be transilluminated
  • Diagnosis
    • Prenatal ultrasound : fluid-filled structure that can be single or multilocular
    • Ultrasound used to identify mass in infancy
    • CT or MRI may be used to further assess anatomical structures for surgical planning.
  • Treatment: : Small masses may regress spontaneously, but surgical excision is indicated to prevent infection of the mass or airway compromise.
  • Prognosis: Reccurence is common following surgical excision of extensive hygromas.

References:[5][8][9]

Differential diagnoses

References:[10][11][7]

The differential diagnoses listed here are not exhaustive.