RESUMO
Fourth branchial pouch anomaly [4BPA] is a rare condition that often presents an extreme diagnostic and therapeutic challenge. It usually causes recurrent left thyroid or perithyroid tissue inflammation, but it can be situated in the right side too. In this case report we present a nine-year-old girl with right sided 4BPA. She was referred for evaluation of recurrent right muscular space mass and fistula that was unresponsive to any medical or surgical procedures. This paper demonstrates the proper technical issues about diagnostic work up and surgical approach that we used to manage her dilemma. In patients with both skin fistula and pyriform sinus opening, external cannulation is more convenient and less traumatizing than internal cannulation