Cervical Viscera

Question 1

What are the three layers of the cervical viscera?

Answer 1

Superficial: Endocrine layer
Middle: Respiratory layer
Deep: Alimentary layer

Question 2

What lies in the endocrine layer of the cervical viscera?

Answer 2

Thyroid gland
Parathyroid glands
Thymus (usually in anterior mediastinum)

Question 3

What lies in the respiratory layer of the cervical viscera?

Answer 3

Larynx and Trachea

Question 4

What lies in the alimentary layer of the cervical viscera?

Answer 4

Pharynx and Esophagus

Question 5

Describe the thyroid gland.

• What layer of the cervical viscera is it found in?
• What does it produce?
• What physical feature unites its lobes?
• What is its arterial supply?
• What is its venous drainage?
• What is it innervated by?

Answer 5

• Found in superficial: endocrine layer
• Produces thyroid hormone and calcitonin
• Its lobes are united by an isthmus
• Arteries - Sup. thyroid artery (from ext. carotid artery) and Inf. thyroid artery (from thyrocervical trunk)
• Veins - Sup. thyroid, Middle thyroid, and Inf thyroid veins
• Innervated by Cervical sympathetic ganglia

Question 6

Describe the parathyroid gland

• On which surface of the thyroid gland are the parathyroid glands found?
• What hormone do they secrete?
• What can occur in the absence of said hormone?
• What are the arterial, venous, and nerve supply for the parathyroid gland?

Answer 6

• Found on posterior surface
• They produce the parathyroid hormone
• In the absence of PTH, blood calcium levels drop, which can result in convulsions or tetany
• Sup and Inf thyroid arteries, Sup, Middle, and Inf thyroid veins, and the cervical sympathetic ganglion (same as Thyroid gland)