Branchial cyst

Also called a branchial cleft cyst, this is a cavity that is a remnant from embryologic development present at birth in one side of the neck just in front of the large angulated muscle on either side (the sternocleidomastoid muscle). The cyst may not be recognized until adolescence as it enlarges its oval shape. It may develop a sinus or drainage pathway to the surface of the skin from which mucus can be expressed. Total surgical excision is the treatment of

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a cyst that arises at the site of one of the embryonic pharyngeal pouch due to a developmental anomaly.

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branchial cleft cyst a cyst arising in the lateral aspect of the neck, from epithelial remnants of a branchial cleft (pharyngeal groove), usually between the second and third pharyngeal arches. Called also cervical lymphoepithelial c. and lymphoepithelial c.

Branchial cleft cyst seen as a well-defined, low-density lesion in an axial contrast-enhanced CT scan through the midlevel of the tongue and base of the mandible. The lateral wall shows thick enhancement (arrow), indicating infection.