Proposed ultrasound algorithm to differentiate thyroglossal duct and dermoid cysts.

Objective: 1) To assess reproducibility of the previously established SIST score. 2) To determine inter-observer agreement in using ultrasound (US) characteristics to differentiate thyroglossal duct cyst (TGDC) from dermoid cysts (DC) 3) Improve the method used to pre-operatively differentiate TGDC from DC.

Study Design: Retrospective chart review.