Thyroid A&P Flashcards
what is the normal size of the thyroid gland in an adult in SAG?
SAG 4-5 cm
what is the normal size of the thyroid gland in an adult in TRV?
TRV 1-2 cm
what is the normal size of the thyroid in AP?
AP 1-2 cm
what is the NL size of the isthmus in AP?
AP 2-6 mm
what vessels run lateral to the thyroid (TRV)?
CCA & jugular vein
what structure lies medial to the thyroid (TRV)?
trachea
what muscles lie anterior to the trachea (TRV)?
strap muscles:
sternothyroid
sternohyoid
sternocleidomastoid
what structures lie posterior to the trachea (TRV)?
longus colli muscle
minor neurovascular bundle
what does the major neurovascular bundle consist of?
CCA
internal jugular vein
vagus nerve
what does the minor neurovascular bundle consist of?
inferior thyroid artery
recurrent laryngeal nerve
what structure lies to the left of midline posteromedial to left lobe?
esophagus
how do you confirm you are imaging the esophagus vs. pathology?
ask patient to swallow. if it changes shape, it’s most likely esophagus.
also image in both planes.
what are some functions of the thyroid gland?
- endocrine gland – synthesizes, stores, secretes hormones
- regulates cell metabolism
what are 3 thyroid hormones?
- thyroxine (T4)
- triiodothyronine (T3)
- calcitonin
where are the superior parathyroid glands?
posterior to the upper poles of the thyroid
where are the inferior parathyroid glands?
posterior to the inferior poles of the thyroid
the parathyroid glands are lateral to the CCA. T/F?
false – they are medial
where are the parathyroid glands compared to the longus colli muscle?
the parathyroid glands lie anterior to the longus colli muscle
normal size of the parathyroid glands?
< 5 mm
what hormone is secreted by the parathyroid gland and what does it do?
parathyroid hormone (PTH) regulates calcium levels in blood and bone
a decrease in calcium may be a sign of parathyroid adenoma. T/F?
false. an INCREASE in calcium may be a sign of parathyroid adenoma
what are 3 congenital variants of the thyroid & parathyroid?
- pyramidal lobe
- ectopic thyroid
- ectopic parathyroid
what is a pyramidal lobe?
a variant of the thyroid gland that looks like a finger-like extension of the isthmus
which side does the pyramidal lobe usually extend from?
left side