Recurrent thyroid abscess - Is it a fourth branchial archanomaly?

Branchial fistulae are of congenital origin(6) and consists of skin lined tract opening internally at junction of cartilaginous and bony meatus in case of 1(st) arch anomaly, tonsillar fossa in case of 2(nd) arch, while 3(rd) and 4(th) arch sinuses have internal opening at level of pyriform sinus or below. A complete tract of 3(rd) or 4(th) arch fistulae is yet to be described. Fourth arch fistulae(1) have a distinct clinical pattern of internal opening at pyriform apex, are left sided and associated with suppurative thyroiditis(3), they manifest at a younger age and treatment involves excision of tract with ipsilateral thyroid lobectomy.