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1. Thyroid Gland Anatomy - I
By:
Dr.Faris Muhammed Al-Haddad
PhD In Human Anatomy
Associate Professor In Human Anatomy
Medical College/ Hawler Medical University
February. 2022

2. Definition
A bi-lobed endocrine
gland located at the
midline of the neck, it
secrets hormones that
regulate metabolism,
growth & development
T H Y R O I D

3. Function
Function

5. Location and Description of The thyroid gland:
The Rt and Lt lobes are connected by an isthmus:
1. Each lobe
• Pear shaped,
• Its apex: being directed upward to
oblique line of the thyroid cartilage;
• Its base: lies below at the level of
4th or 5th tracheal ring.

6. 2. Isthmus
• Connects between Rt & Lt lobes
• Extends across the midline in
front of the:
2nd
3rd
4th
tracheal rings
Location and Description of The thyroid gland
Cont.

7. Location and Description of The thyroid gland
3. Pyramidal lobe
• is often present,
• it projects upward from the isthmus, usually
to the left of the midline
• Its connected to the hyoid bone by either:
• Fibrous band
• Muscular band, it is referred to as
the levator glandulae thyroideae
Pyramidal lobe
levator
glandulae
thyroideae
Cont.

8. surrounded by a sheath derived
from the:
The sheath attaches the gland to
the larynx & the trachea.
Fasciae
Pretracheal layer of deep fascia.

9. Capsules of Thyroid Gland
1. True capsule: is its own connective tissue
2. False capsule:
• from the pretracheal layer of the
deep cervical fascia
• It is thin along the posterior border
of the lobes
• It is thick on the inner surface of the
gland where it forms a suspensory
ligament (of Berry), which connects
the lobe to the cricoid cartilage

11. End of Part 1