Branchial Anomalies (NEET PG Focus)
Branchial anomalies arise from the failure of the branchial apparatus to regress. They are essential differential diagnoses for lateral neck masses.
| Anomaly | Location | High-Yield Clinical Pearl |
|---|---|---|
| 1st Branchial Cleft | Near the angle of the mandible/parotid region. | Proximity to the Facial Nerve (CN VII). |
| 2nd Branchial Cleft | Anterior border of the SCM muscle (most common). | Passes between the internal and external carotid arteries. |
| 3rd/4th Branchial Cleft | Lower neck, often the piriform sinus. | Rare; 4th cleft anomalies often present as recurrent thyroiditis. |
3. Key Distinctions
- Cyst vs. Fistula: A cyst is a closed sac; a fistula has an opening both internally (into the pharynx) and externally (on the neck skin).
- Location Matters: Any lateral neck mass in a child is a branchial cyst until proven otherwise. In an adult, you must rule out metastatic squamous cell carcinoma (often from the tonsil or tongue base).
NEET PG Hint: The 2nd branchial cleft cyst is the most common type. Remember that it tracts deep to the platysma and superficial to the carotid sheath. If a question mentions a neck mass that moves on swallowing, it is likely a thyroglossal duct cyst, not a branchial cyst.