Anatomy: Thyroid

Question 1

What connects the two lobes of the thyroid

Answer 1

the isthmus

Question 2

What does the isthmus lie anterior to?

Answer 2

The 2nd and 3rd cartilages of the trachea

Question 3

Where are the parathyroid glands located

Answer 3

the posterior surface of the lateral lobes of the thyroid

Question 4

Where does the thyroid begin in an embryo

Answer 4

as a midline epithelial proliferation at the junction between the anterior 2/3rds and posterior 1/3rd of the tongue

Question 5

How does the thyroid remain attached to the tongue as it descends

Answer 5

thyroglossal duct

Question 6

When does the gland reach its final position

Answer 6

by the 7 week of development

Question 7

What nerve supplies the platysma

Answer 7

Facial nerve

Question 8

What muscles are enclosed by the investing fascia

Answer 8

trapezius

SCM

Question 9

What structures are contained in the carotid sheaths

Answer 9

The internal jugular vein
Carotid arteries
Vagus nerves
Deep cervical lymph nodes

Question 10

What structures are enclosed in the pretracheal fascia

Answer 10

the strap muscles
thyroid gland
the trachea
the oesophagus
the recurrent laryngeal nerves

Question 11

What is the name of the space lying between the pretracheal and prevertebral fascia

Answer 11

the retropharyngeal space

Question 12

Name the attachments of the SCM

Answer 12

The manubrium of the sternum
The clavicles
The mastoid process of the temporal bone

Question 13

Where does the anterior jugular vein drain

Answer 13

the external jugular vein

Question 14

Where dies the external jugular vein drain

Answer 14

the subclavian vein

Question 15

What nerve supplies the SCM and trapezius

Answer 15

the spinal accessory

Question 16

Where do the carotid sheaths attach superiorly at the base of the skull

Answer 16

the jugular foramen and the entrance to the carotid canal

Question 17

What arteries supply the thyroid

Answer 17

SUperior and inferior thyroid arteries

branches of the common carotid

Question 18

What veins supply the thyroid

Answer 18

Superior middle and inferior thyroid veins (branches of the internal jugular vein)

Question 19

Where does lymph from the thyroid drain

Answer 19

the superior and inferior deep cervical lymph nodes

tracheal lymph nodes - pretracheal node and the paratracheal node

Question 20

Where does lymph from the right superior and inferior deep cervical nodes drain to

Answer 20

the right venous angle via the right lymphatic duct

Question 21

Where does the lymph from the left the superior and inferior deep cervical lymph nodes drain to

Answer 21

the left venous angle via the thoracic duct

Question 22

What supplies somatic motor to the muscles that move the vocal cords

Answer 22

right recurrent laryngeal nerve

Question 23

What does unilateral recurrent laryngeal nerve injury cause

Answer 23

hoarsness or weakness of the voice

Question 24

What does bilateral injury of the recurrent nerve cause

Answer 24

aphonia

inability to close the rima glottidis

Question 25

What does bilateral injury of the recurrent nerve cause

Answer 25

aphonia

inability to close the rima glottidis

Question 26

Where is the incision made in a classic thyroidectomy

Answer 26

collar inscision in a neck fold following LANGER’s lines