Absite: Thyroid Verified Exam Questions and Answers Latest update
2026/2027
Question:
thyroid source
Answer:
1st and 2nd pharyngeal ARCHES (not pouches)
Question:
thyroid hormone pathway
Answer:
TRF (hypothal) ---> TSH (anterior pituitary) ---> T3 and T4 release from thyroid (through mechanism
that involved inc cAMP) ---> negative feedback loop to TRF and TSH
Question:
thyroid arterial supply
Answer:
(1) superior thyroid artery = 1st branch from external carotid ... (2) inferior thyroid artery = off
thyrocervical trunk (branch of subclavian), supplies BOTH inferior and superior parathyroids, **ligate
close to thyroid to avoid injury to parathyroid glands in thyroidectomy ... (3) Ima artery = occurs in
1%, arise from innominate or aorta and goes to isthmus
Question:
thyroid venous drainage
Answer:
superior and middle thyroid veins = drain into IJ vein .... inferior thyroid vein = drains into innominate
vein
Question:
how to avoid parathyroid complications in thyroidectomy
Answer:
ligate close to thyroid to avoid injury to parathyroid glands in thyroidectomy .... inferior thyroid artery
= off thyrocervical trunk (branch of subclavian), supplies thyroid and inferior and superior
parathyroids
,Question:
thyroid innervation: name
Answer:
superior laryngeal nerve and recurrent laryngeal nerves (RLNs)
Question:
thyroid innervation: function
Answer:
superior = motor to cricothyroid muscle .... RLN = motor to all larynx except cricothyroid muscle
Question:
thyroid innervation: describe course and surrounding structures
Answer:
superior = runs LATERAL to thyroid lobes, tracks close to superior thyroid artery but is variable ...
RLN = runs POSTERIOR to thyroid lobes in tracheoesophageal groove, tracks with inferior thyroid
artery but variable
Question:
thyroid innervation: injury leads to what?
Answer:
superior = loss of projection and easy voice fatigue (classic ex is opera singer) ... RLN = hoarseness,
b/l can obstruct airway and may need emergent airway
Question:
thyroid innervation: describe RLN locations
Answer:
L loops around aorta vs R loops around innominate artery
Question:
thyroid innervation: describe RLN variations
Answer:
non-recurrent laryngeal nerve in 2%, more common on R ... risk of injury is higher for a non-recurrent
laryngeal nerve during thyroid surgery
Question:
ligament of berry - describe
Answer:
posterior medial suspensory ligament close to RLNS, needs careful dissection
, Question:
thyroblogulin - function, types and relative amnts and production
Answer:
stores T3 and T4 in colloid ... plasma T4:T3 ratio is 15:1 .... T3 is the more active form (tyrosine +
iodine) ... most T3 is made in periphery from T4 to T3 conversion by deiodinases
Question:
peroxidase and deiodinase functions
Answer:
peroxidase = link iodine and tyrosine together (form T3, more active form) .... deiodinase = separate
iodine from tyrosine
Question:
thyroxine-binding globulin function
Answer:
thyroid hormones transport, binds majority of T3 and T4 in circulation
Question:
measure thyroid gland function
Answer:
TSH is the most sensitive indicator
Question:
tubercle of Zuckerkandl: location, surgical considerations
Answer:
most lateral, posterior extension of thyroid tissue ... intraop = rotate medially to find RLNs, leave this
portion behind with subtotal thyroidectomy b/c of proximity to RLNs
Question:
parafollicular C cells function
Answer:
produce calcitonin
Question:
thyroxine treatment effect and SE
Answer:
TSH levels should fall 50%, osteoporosis is long-term SE
2026/2027
Question:
thyroid source
Answer:
1st and 2nd pharyngeal ARCHES (not pouches)
Question:
thyroid hormone pathway
Answer:
TRF (hypothal) ---> TSH (anterior pituitary) ---> T3 and T4 release from thyroid (through mechanism
that involved inc cAMP) ---> negative feedback loop to TRF and TSH
Question:
thyroid arterial supply
Answer:
(1) superior thyroid artery = 1st branch from external carotid ... (2) inferior thyroid artery = off
thyrocervical trunk (branch of subclavian), supplies BOTH inferior and superior parathyroids, **ligate
close to thyroid to avoid injury to parathyroid glands in thyroidectomy ... (3) Ima artery = occurs in
1%, arise from innominate or aorta and goes to isthmus
Question:
thyroid venous drainage
Answer:
superior and middle thyroid veins = drain into IJ vein .... inferior thyroid vein = drains into innominate
vein
Question:
how to avoid parathyroid complications in thyroidectomy
Answer:
ligate close to thyroid to avoid injury to parathyroid glands in thyroidectomy .... inferior thyroid artery
= off thyrocervical trunk (branch of subclavian), supplies thyroid and inferior and superior
parathyroids
,Question:
thyroid innervation: name
Answer:
superior laryngeal nerve and recurrent laryngeal nerves (RLNs)
Question:
thyroid innervation: function
Answer:
superior = motor to cricothyroid muscle .... RLN = motor to all larynx except cricothyroid muscle
Question:
thyroid innervation: describe course and surrounding structures
Answer:
superior = runs LATERAL to thyroid lobes, tracks close to superior thyroid artery but is variable ...
RLN = runs POSTERIOR to thyroid lobes in tracheoesophageal groove, tracks with inferior thyroid
artery but variable
Question:
thyroid innervation: injury leads to what?
Answer:
superior = loss of projection and easy voice fatigue (classic ex is opera singer) ... RLN = hoarseness,
b/l can obstruct airway and may need emergent airway
Question:
thyroid innervation: describe RLN locations
Answer:
L loops around aorta vs R loops around innominate artery
Question:
thyroid innervation: describe RLN variations
Answer:
non-recurrent laryngeal nerve in 2%, more common on R ... risk of injury is higher for a non-recurrent
laryngeal nerve during thyroid surgery
Question:
ligament of berry - describe
Answer:
posterior medial suspensory ligament close to RLNS, needs careful dissection
, Question:
thyroblogulin - function, types and relative amnts and production
Answer:
stores T3 and T4 in colloid ... plasma T4:T3 ratio is 15:1 .... T3 is the more active form (tyrosine +
iodine) ... most T3 is made in periphery from T4 to T3 conversion by deiodinases
Question:
peroxidase and deiodinase functions
Answer:
peroxidase = link iodine and tyrosine together (form T3, more active form) .... deiodinase = separate
iodine from tyrosine
Question:
thyroxine-binding globulin function
Answer:
thyroid hormones transport, binds majority of T3 and T4 in circulation
Question:
measure thyroid gland function
Answer:
TSH is the most sensitive indicator
Question:
tubercle of Zuckerkandl: location, surgical considerations
Answer:
most lateral, posterior extension of thyroid tissue ... intraop = rotate medially to find RLNs, leave this
portion behind with subtotal thyroidectomy b/c of proximity to RLNs
Question:
parafollicular C cells function
Answer:
produce calcitonin
Question:
thyroxine treatment effect and SE
Answer:
TSH levels should fall 50%, osteoporosis is long-term SE
