🐭 RAT series
Points to Ponder for NEET-PG, FMGE & NEXT
- The thyroid gland is located in the anterior neck, below and lateral to the thyroid cartilage.
- Has two lateral lobes connected by a central isthmus.
- The visceral fascia anchors the thyroid gland to the laryngoskeleton.
- Key arteries supplying the thyroid gland include the superior and inferior thyroid arteries, with a possible contribution from the thyroid ima artery (occasionally present).
- Venous drainage occurs via the superior, middle, and inferior thyroid veins.
- Lymphatic drainage involves the paratracheal and deep cervical nodes.
Gross Anatomy and Relations:
- Location: Anterior neck, below and lateral to the thyroid cartilage
- Lateral surface: Covered by the sternothyroid muscle.
- Its attachment to the oblique line of the thyroid cartilage limits superior movement.
- Anterior: Overlapped by the sternohyoid and omohyoid muscles (superior belly), with the sternocleidomastoid muscle bordering anteriorly and inferiorly.
Structure:
- Lobes: Two lateral lobes connected by a central isthmus
- Fascia: Unsheathed by the visceral fascia, firmly attaching it to the laryngoskeleton
- Posterior suspensory ligament (Berry ligament): Attaches the posteromedial aspect of the gland to the cricoid cartilage and first and second tracheal rings.
Arterial supply:
- Superior thyroid artery (first branch of external carotid artery)
- Inferior thyroid artery (branch of the thyrocervical trunk, arising from the subclavian artery)
- Occasionally: Thyroid ima artery (arises from the aortic arch or brachiocephalic trunk)
Veinous drainage:
- Superior and middle thyroid veins drain into the internal jugular vein.
- Inferior thyroid vein drains into the brachiocephalic vein.
Lymphatic Drainage:
- Paratracheal nodes
- Deep cervical nodes inferior to the omohyoid muscle, along the internal jugular vein
Quiz