Parathyroid/thyroid anatomy

Question 1

how many lobes is the thyroid gland made up of

Answer 1

2 lateral lobes

sometimes a middle pyramidal lobe

Question 2

what connects the two lobes of the thyroid

Answer 2

isthmus

Question 3

where to the thyroid lobes attach

Answer 3

to the lateral aspects of the thyroid and cricoid cartilage and trachea

Question 4

what is the location of the isthmus

Answer 4

anterior to the 2nd and 3rd cartialges of the trachea

Question 5

what happens to thyroid lumps due to swelling

Answer 5

they move superiorly then inferiorly with the larynx

Question 6

how many parathyroid glands are there

Answer 6

4

Question 7

where are the parathyroid glands located

Answer 7

the posterior surfaces of the thyroid glands lateral lobes

Question 8

what is the pyramidal lobe of the thyroid

Answer 8

lobe that runs up the middle
only seen in 28-55% of people
most commonly originates from the left lateral lobe

often attach superiorly to the thyroid cartilage

Question 9

where does the thyroid begin development in embryology

Answer 9

between the anterior 2/3rds and posterior 1/3rd of the tongue (this is called foramen caecum in adults)

Question 10

what keeps the thyroid gland attached to the tongue when it migrated inferiorly

Answer 10

the thyroglossal duct

Question 11

when does the thyroid gland reach its final position in relation to the larynx/trachea

Answer 11

7th week of development

Question 12

what cervical level is the thyroid at

Answer 12

C7

Question 13

what thin muscle is located anterior - lateral to the thyroid gland in the superficial fascia

Answer 13

Platysma muscle

nerve supply - facial

Question 14

what are the 4 fascial compartments of the neck

Answer 14

prevertebral (deep) fascia
Investing fascia
2 carotid sheaths
Pretracheal fascia

Question 15

what is inside of the prevertebral fascia

Answer 15

postural neck muscles

cervical vertebrae

Question 16

what is inside of the investing fascia

Answer 16

trapezius

sternosleidomastoid

Question 17

what is inside of the carotid sheaths

Answer 17

vagus nerve
deep cervical lymph nodes
carotid arteries
internal jugular vein

Question 18

what is inside the pretracheal fascia

Answer 18

oesophagus 
trachea 
thyroid gland 
trap muscles 
recurrent laryngeal nerves

Question 19

which cranial nerve innervated the sternocleidomastoid and trapezius

Answer 19

CNXI

spinal accessory

Question 20

where do the two heads to the sternocleidomastoid muscle attach

Answer 20

sternal head attaches to sternum

clavicular head attached to clavicle

both heads attach to the mastoid process of the temporal bone

Question 21

where do the carotid sheaths attach

Answer 21

superiorly to the base of the skull (around the jugular foramen and entrance to carotid canal)

inferiorly blend with the mediastinal fascia

Question 22

what vessels supply blood to they thyroid and parathyroid glands

Answer 22

superior thyroid artery (off of the right carotid)
inferior thyroid artery (off of the right subclavian)
thyroid ima artery (also off the right carotid)

Question 23

what veins drain blood from the thyroid

Answer 23

superior thyroid vein
middle thyroid vein
inferior thyroid vein

Question 24

where does blood from the superior and middle thyroid veins drain into

Answer 24

the internal jugular veins

Question 25

where does the internal jugular vein and the inferior thyroid vein drain into

Answer 25

the brachiocephalic veins

Question 26

where does the brachiocephalic vein drain into

Answer 26

SVC

Question 27

what lymph nodes drain lymph from the thyroid

Answer 27

superior deep cervical lymph nodes

inferior deep cervical lymph nodes

the tracheal lymph nodes
(pretracheal and paratracheal)

Question 28

where is lymph returned to via the right lymphatic duct

Answer 28

right venous angle

Question 29

where is lymph returned to via the thoracic duct

Answer 29

left venous angle

Question 30

where does the vagus nerve exit the skull and what does it travel down inside (NECK)

Answer 30

exits via jugular foramen

decides through carotid sheath

Question 31

where can both vagus nerves be found in the thorax

Answer 31

posterior to the lung hilum and on the oesophagus

Question 32

how to the vagus nerves pass through the diaphragm

Answer 32

on the oesophagus

Question 33

what does the vagus nerve supply the abdominal organs with in the distal midgut

Answer 33

parasympathetic axons

Question 34

where does the left recurrent laryngeal nerve loop around

Answer 34

the arch of the aorta

Question 35

where does the right recurrent laryngeal nerve loop around

Answer 35

the right subclavian and right common carotid arteries (where the brachiocephalic splits)

Question 36

what are the 4 strap muscles

Answer 36

Omohyoid (shoulder to hyoid bone)
Sternohyoid (sternum to hyoid bone)
Thyrohyoid (thyroid cartilage to hyoid bone)
Sternothyroid (sternum to thyroid cartilage)

Question 37

where is the incision made in a classical thyroidectomy

Answer 37

‘collar’ incision made with natural skin crease of the neck just superior to the clavicles and jugular notch

made through skin and platysma muscles

Question 38

what happens if there is injury to the recurrent laryngeal nerves

Answer 38

paralysis of the vocal cords

Question 39

unilateral recurrent laryngeal nerve injury consequence

Answer 39

hoarseness or weakness of the voice and weak cough

Question 40

bilateral injury of the recurrent laryngeal nerve consequence

Answer 40

aphonia (inability to produce sounds) and inability to close rima glottidis (opening between vocal cords) to prevent aspiration

also inability to produce a good cough