Jacobs Journal of Anatomy and Physiology

Prevalence of Dual Thyroid Ectopy in a Surgical Patient Population

*Sharon H. Gnagi
Department Of Otolaryngology Head And Neck Surgery, Mayo Clinic Arizona, Arizona, United States

*Corresponding Author:
Sharon H. Gnagi
Department Of Otolaryngology Head And Neck Surgery, Mayo Clinic Arizona, Arizona, United States
Email:Gnagi.sharon@mayo.edu

Published on: 2015-07-24

Abstract

Objectives: Dual ectopic thyroids are considered rare events previously reported to occur in 9% of patients with ectopic thyroids. The objective of this study is to report an observed elevated prevalence of dual thyroid ectopy detected in patients presenting for surgical treatment of ectopic thyroids. Study Design: Retrospective case series. Methods: Surgical records at three tertiary academic referral centers were searched to identify patients undergoing ectopic thyroid excision from 1994 - 2012. Medical records and radiographic studies were reviewed by two independent reviewers. Results: During the study period, 10 patients underwent surgical excision of ectopic thyroid tissue. Dual foci of ectopic thyroid tissue were identified in 4 patients. In all cases, one focus of ectopic tissue was lingual in location and the second focus was infrahyoid. No patients had an orthotopic gland. Conclusions: A high prevalence of dual thyroid ectopy was detected in our patient population likely secondary to the use of comprehensive imaging studies in all patients. This suggests that a thorough evaluation of patients with ectopic thyroid tissue may identify additional occult foci.

Keywords

Ectopic Thyroid, Dual Ectopic Thyroid, Multifocal Ectopic Thyroid, Lingual Thyroid

Introduction

Ectopic thyroids are rare developmental abnormalities created by aberrant descent of the thyroid from its origin at the base of the tongue. The estimated prevalence of thyroid ectopy is 1:100,000 - 300,000. Although ectopic thyroid tissue can occur throughout the body, most commonly it is located along the path of normal developmental descent including lingual (77 - 90%) and midline cervical locations (10 - 33%). Within this patient population, dual foci of ectopic tissue are infrequent and the literature is primarily limited to case reports and small series. The prevalence of dual thyroid ectopy has previously been estimated at 9%. We present our 18 year experience with ectopic thyroids and elevated prevalence of dual ectopy.