A 30-year-old woman presents with a cystic, fluctuant swelling in the anterior triangle of the neck at the junction of the upper and middle third, anterior to the sternocleidomastoid. It transilluminates brightly and moves on swallowing and tongue protrusion. The most likely diagnosis is:
- A Thyroglossal duct cyst
- B Cystic hygroma
- C Branchial cleft cyst (2nd arch) ✓
- D Dermoid cyst
Correct answer: C. Branchial cleft cyst (2nd arch)
Explanation
Second branchial cleft cysts classically present as cystic swellings at the anterior border of the upper-middle third of the SCM, deep to the platysma and along the carotid sheath. They are cystic and transilluminate. They do not move with tongue protrusion (which is characteristic of thyroglossal cyst). Cystic hygromas are multiloculated and transilluminate brilliantly but occur in the posterior triangle (supraclavicular). Dermoid cysts are midline, submental.
Reference: Dhingra Diseases of Ear, Nose and Throat, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.