Introduction: Congenital pyriform sinus fistula is recognized as a potential cause of recurrent cervical inflammation, recurrent abscess, and acute suppurative thyroiditis. Failure to recognize this diagnosis may result in recurrence following administration of antibiotics and incision and drainage. This study reflects the authors' experience in treating four patients with this diagnosis.
Materials and methods: Patients included three children and one adult ranging in age from 7 to 34 years. The steps necessary to confirm the diagnosis and the subsequent surgical treatment are reviewed.
Results: All fistula occurred on the left side. In each case the fistula originated in the apex of the pyriform sinus. It subsequently penetrated the inferior constrictor in three cases and the thyroid cartilage in one to end in the thyroid gland or perithyroid tissue. The opening of the pyriform sinus fistula could be identified by either barium swallow or direct endoscopy. Complete fistulectomy resulted in resolution of symptoms in all cases.
Conclusion: Pyriform sinus fistula is a rare entity. It may be of fourth branchial pouch origin. Identification of the fistula opening in the pyriform sinus may be difficult or impossible during acute inflammation because of edema. The authors advocate the fistula be exposed through incision of the inferior constrictor muscle, which facilitates total removal. Resection of the fistula, adjacent scar tissue, and a portion of the thyroid gland when the fistula is attached, should be regarded as essential steps in curing this entity.