Congenital fistula of the fourth branchial pouch.

Between 1986 and 1995, 128 patients were treated for various head and neck congenital malformations at Saint-Luc University Hospital, Louvain. We report three cases of fourth branchial pouch cysts requiring surgical removal. One of these cases presented with a third branchial pouch remnant on the same side and subsequently a fourth branchial pouch sinus. To our knowledge, this is the first case published in the literature. A fourth branchial pouch sinus tract can become manifest clinically by recurrent episodes of neck abscess or acute suppurative thyroiditis (especially in infants). The tract can be identified with a barium swallow during the period of latency and hypopharyngeal endoscopy under general anesthesia. Total excision of the fistula with dissection up to the pyriform sinus with or without a left thyroid gland lobectomy and isthmectomy is the treatment of choice.