Gland
Superior parathyroid gland
Fourth-pouch endocrine gland usually behind the upper thyroid
High-yield
The superior glands arise from pouch four, while the inferior glands descend farther with the third-pouch thymic tissue.
Overview
Superior parathyroids arise from the fourth pharyngeal pouches. Their relatively short migration produces a more consistent position than that of inferior glands, usually behind the upper or middle thyroid lobe. This pattern remains variable and does not make a single landmark universally reliable.
Reference facts
- Location
- Usually posterior to the upper-to-middle thyroid lobe and deep to the recurrent laryngeal nerve's plane, near the cricothyroid region.
- Hormones
- Chief cells are the principal PTH-producing cells. Oxyphil cells are also present and cannot categorically be treated as nonsecretory.
- Blood supply
- Commonly inferior thyroid arterial branches, with superior thyroid contributions in some glands.
- Innervation
- Autonomic fibers are largely vascular; calcium-sensing receptors provide the principal link between blood calcium and secretion.
- Function
- PTH supports blood calcium through renal, skeletal and vitamin-D pathways and promotes phosphate loss in urine; bone effects depend on the pattern of exposure.
Mnemonic
Pouch four finishes higher; pouch three travels with the thymus.
Clinical correlation
Loss of adequate functioning parathyroid tissue or its blood supply can cause hypocalcemia. The important issue is remaining functional reserve, not simply whether one named gland has been injured.
Frequently asked questions
Where is the superior parathyroid gland located?
Usually posterior to the upper-to-middle thyroid lobe and deep to the recurrent laryngeal nerve's plane, near the cricothyroid region.
What does the superior parathyroid gland secrete?
Chief cells are the principal PTH-producing cells. Oxyphil cells are also present and cannot categorically be treated as nonsecretory.
What does the superior parathyroid gland do?
PTH supports blood calcium through renal, skeletal and vitamin-D pathways and promotes phosphate loss in urine; bone effects depend on the pattern of exposure.
What is the blood supply of the superior parathyroid gland?
Commonly inferior thyroid arterial branches, with superior thyroid contributions in some glands.