Which cyst is usually located at the lateral neck near the angle of the mandible?

Which cyst is usually located at the lateral neck near the angle of the mandible?

• A. Brachial Cleft Cyst
• B. Thyroglossal Duct Cyst
• C. Colloid Cyst
• D. Dermoid Cyst

Answer: (A)

Remnants of the second branchial cleft commonly form a cyst that sits in the lateral neck along the anterior border of the sternocleidomastoid muscle, near the angle of the mandible. This is why a branchial cleft cyst is the typical finding in that exact location. Embryologically, the second branchial cleft lies in that region, so cysts from these remnants appear laterally rather than in the midline. Clinically they present as a painless lateral neck mass, and ultrasound usually shows a well-defined, thin-walled cyst that may contain debris if infected. By contrast, a thyroglossal duct cyst is midline and moves with swallowing or tongue protrusion, a colloid cyst is intracranial (within the ventricles), and dermoid cysts are often midline or in other facial/neck locations rather than specifically near the angle of the mandible.

Remnants of the second branchial cleft commonly form a cyst that sits in the lateral neck along the anterior border of the sternocleidomastoid muscle, near the angle of the mandible. This is why a branchial cleft cyst is the typical finding in that exact location. Embryologically, the second branchial cleft lies in that region, so cysts from these remnants appear laterally rather than in the midline. Clinically they present as a painless lateral neck mass, and ultrasound usually shows a well-defined, thin-walled cyst that may contain debris if infected. By contrast, a thyroglossal duct cyst is midline and moves with swallowing or tongue protrusion, a colloid cyst is intracranial (within the ventricles), and dermoid cysts are often midline or in other facial/neck locations rather than specifically near the angle of the mandible.