Pharyngeal pouch (embryology)

Specific pouches

First pouch

Second pouch

• Contributes the middle ear, palatine tonsils, supplied by the facial nerve.

  Third pouch

• The third pouch possesses Dorsal and Ventral wings. Derivatives of the dorsal wings include the inferior parathyroid glands, while the ventral wings fuse to form the cytoreticular cells of the thymus. The main nerve supply to the derivatives of this pouch is Cranial Nerve IX, glossopharyngeal nerve.

  Fourth pouch

• superior parathyroid glands and ultimobranchial body which forms the parafollicular C-Cells of the thyroid gland.
• Musculature and cartilage of larynx.
• Nerve supplying these derivatives is Superior laryngeal nerve.

  Fifth pouch

• Rudimentary structure, becomes part of the fourth pouch contributing to thyroid C-cells.

  Sixth pouch

• The fourth and sixth pouches contribute to the formation of the musculature and cartilage of the larynx. Nerve supply is by the recurrent laryngeal nerve.