A case of third branchial cleft cyst

Abstract

Branchial cyst or congenital cystic lesions of neck originate from branchial clefts, the 2^nd branchial cleft cyst being the most common and 3^rd and 4^th being missed. Hence, they are often misdiagnosed as lymph nodal masses, cold abscess. We are reporting a case of 3^rd Branchial cleft cyst, of a 12-year-old boy who presented with left sided recurrent painful cystic mass at the level of hyoid bone going down to the level of pyriform fossa. All the tests for tuberculosis were negative. USG neck revealed loculated thick walled cyst from SCM to lateral part of pharynx. CECT revealed a thick-walled cyst extending from the anterior border of the sternocleidomastoid going down obliquely below the level of thyrohyoid membrane to pyriform fossa. Exploration revealed a thick walled infected cyst, pushing left upper pole of thyroid medially and anterior to left sided superior laryngeal nerve. The cyst was going downwards medially below the level of thyrohyoid membrane. The cyst was excised completely. Histopathology revealed the findings of squamous epithelial lining of cyst wall and cholesterol crystals within. Detailed anatomy on CECT, surgery and histopathology confirmed 3^rd arch Branchial cyst.