Dual ectopy: Unique appearance of ectopic thyroid

Abstract

A 67-year-old female underwent a computed tomography angiogram (CTA) of the head in the setting of acute, short-term memory loss. Two lobulated hyperattenuating lesions were incidentally discovered at the base of the tongue and the hyoid bone. Upon further investigation in the outpatient setting including further imaging and ultrasound-guided biopsy, the lesions were confirmed to be ectopic thyroid tissue with dual ectopy. Heterotopic tissue, especially when arising at separate sites, can be concerning for a broad differential diagnosis including malignancy, and further evaluation is certainly recommended. When evaluating possible heterotopic tissue, one must always keep in mind the expected embryologic development of the organ in question. Further, in cases where biopsy is less favorable, consideration of the heterotopic tissue's expected physiology is equally important. With these 2 facts in mind, midline hyperattenuating, enhancing lesions in the neck must always be considered to be a possible developmental anomaly of the thyroid, even when there are multiple lesions.

Keywords

• Thyroid
• Ectopic
• Anatomy
• Radiology
• Biopsy
• CT