Gross Anatomy of the Thyroid Gland

The thyroid gland is composed of two lobes connected by a narrow band of thyroid tissue called the isthmus. The lobes are lateral to the upper portion of the trachea just inferior to the larynx, and the isthmus extends across the anterior aspect of the trachea. The thyroid gland is one of the largest endocrine glands, with a weight of approximately 20 g. It is highly vascular and appears more red in color than the surrounding tissues.