Thyroid Flashcards
___ is the fascia that coveres the thyroid
loose investing fascia
___ ligament attaches the thyroid gland to the cricoid cartilage
ligament of berry
the ligament of berry arises from what fascia
pre-tracheal fascia
arteries that supply the thyroid gland
superior thyroid artery
inferior thyroid artery
Aside from supplying the upper 1/3 of the lobe, the superior thyroid artery also supplies ____
upper 1/2 of the isthmus
the inferior thyroid artery is a branch of ___
thyrocervical trunk
The tributaries of the superior and middle thyroid vein
internal jugular vain
the tributary of the inferior thyroid vein
brachiocephalic vein
This nerve loops around the ligamentum arteriosum
left RLN
this loops around the subclavian artery
right RLN
this nerve crosses the arch of the aorta
left RLN
this nerve ascends at the tracheoesophageal groove
left RLN
Damage to one RLN leads to paralysis of the ____ (ipsilateral/contralateral) cord
ipsilateral cord
___ is a sensory nerve to supraglottic larynx
Internal branch of the superior laryngeal nerve
what are the branches of the superior laryngeal nerve?
internal and external branch
___ is the only motor NS to cricothyroid
external branch of the superior laryngeal nerve
what nerve is affected if…
inability to tense the cord
difficulty hitting high notes
voice fatigue
external branch of the superior laryngeal nerve
what descends alongside the external branch of the superior laryngeal nerve?
superior thyroid vessels
serum TSH levels reflect the ability of the anterior pituitary to detect ___ (FT3/FT4)
FT4
this reflects the output from the thyroid gland
total T4
NOT FT4
this reflects the peripheral thyroid hormone metabolism
Total T3
NOT FT3
this detects early hyperthyroidism
FT3
___ syndrome
endorgan resistance to T4
FT4 increased
TSH normal
Refetoff Syndrome
most important in monitoring differentiated thyroid cancer recurrence, after total thyroidectomy and RAI ablation
serum thyroglobulin
this is secreted by C cells
calcitonin
serum calcitonin is a sensitive marker of _____ cancer
medullary thyroid
[thyroid imaging]
I 123 vs I 131, which considered a low dose radiation
I 123
This radionuclide is better in detecting papillary and follicular CA
Iodine 131
[WHO GRADE OF THYROID SIZE]
goiter palpable
but not visible in normal head positon
Grade II
[diagnose]
female, 40-60 years old
heat intolerance, weight loss, diarrhea, palpitation, amenorrhea, afib, ophthalmopathy, dermopathy
graves disease
genes associated with graves disease
HLA B8
HLA DR3
HLA DQA1
[diagnose]
low TSH
with or without elevated FT4/FT3
(+) ophtalmopathy, female
graves
[pharma]
drugs that block synthesis of new T4 and T3
Methimazole Amiodarone Lithium Iodine PTU
MA LIP
[pharma]
drugs that block TRH stimulation
Somatostatin
Glucocorticoids
[pharma]
drugs that block pituitary secretion
dopamin
[pharma]
Drug that block peripheral conversion of T4 ot T3
Propanolol, PTU
Amiodarone
Glucocorticoids
Iopanic acid
PAGI
[pharma]
causes congenital aplasia/aplasia cutis
methimazole
[pharma]
drugs that cause agrarnulocytosis
PTU
Methimazole
What is the dose of I 131 as treatment for graves?
Oral dose 8-12 mCi
absolute contraindication for RAI therapy
pregnancy
breastfeeding
this is given 7 to 10 days prior to thyroidectomy
KISS
Potassium iodide saturated solution is given prior to thyroidectomy because
it decreases vascularity of the thyroid
Also called plummers disease
toxic multinodular goiter
[diagnose]
Graves SSx
(-) ophthalmopathy
TMNG
[diagnose]
younger patient
low TSH
high FT4/FT3
hot nodule
Toxic adenoma
A burch-wartofsky score of 40 means that the patient is ___
impending storm (25 to 45)
in cases of recurrent acute thyroiditis, you suspect ____ fistula
pyriform sinus
[diagnose]
painful thyroid, 30-40 years old, women, previous history of URTI
What is the etiology?
Subacute thyroiditis, viral
self limited
most common inflammatory disorders of the thyroid gland
hashimoto thyroiditis
leading cause of hypothyroidism
hashimoto thyroiditis
[diagnose]
CD8 T cells and antibodies directed agains
Tg, TPO and TSH, HLA B8 HLA DR3, HLA DR5
hashimoto thyoiditis
[diagnose]
woman (30–50)
moderately painless diffusely enlarged thyroid gland
high TSH
hashimoto thyroiditis
[diagnose]
painless, hard anterior neck mass
hard, woody thyroid gland
reidel thyrodiits
Wedge resection
L thyroxine
the single most important test in the evaluation of thyroid nodules
FNAB
What is the cut off to say that the FNAB has optimum cytology?
Follicles: at least 6
contains: 10-15 cells in each follicle
Aspirates: 2 aspirates
These types of CA cant be diagnosed by FNAB
Follicular
Hurthle cell CA
FNAB is less reliable in?
patients with history of radiation
Family history of thyroid CA
what is the risk of malignancy for cold nodules
20%
[Management of thyroid cytopathology]
Non-diagnostic/Unsatisfactory
Repeat FNAB with UTZ guided
1-4% risk of CA
[Management of thyroid cytopathology]
Benign
critical follow-up
[Management of thyroid cytopathology]
Atypia of undetermined significance
OR
Follicular lesion of undetermined significance
Repeat FNA
Diagnostic modality that is useful for detecting nonpalpable thyroid nodules
ultrasound
Characteristic of a malignancy in a cervical lymph node
taller than wide
loss of fatty hilym
Papillary thyroid CA accounts for what percent of all thyroid malignancies?
80%
[diagnose: type of MEN]
- Pituitary adenoma
- Parathyroid hyperplasia
- Pancreatic tumor
MEN 1
[diagnose: type of MEN]
- Parathyroid hyperplasia
- Medullary thyroid CA
- Pheochromocytoma
MEN 2A
[diagnose: type of MEN]
- Medullary thyroid CA
- Pheochromocytoma
- Mucosal neuroma
- Marfanoid body habitus
MEN 2B
What thyroid malignancy is common in iodine deficient areas?
follicular CA
This thyroid malignancy relies on the presence of capsular and vascular invasion
hurthle cell CA
[diagnose: thyroid malignancy]
not avid for RAI
more likely to metastasize to LN and distant sites
hurthle cell CA
What is the thyroglobulin value during post-op surveillance if the patient is taking levothyroxine?
<0.2 ng/mL
What is the thyroglobulin value during post-op surveillance when the patient is hypothyroid?
<1ng
___ CA that arises from the parafollicular cells
medullary thyroid CA
what is the premalignant lesion for medullary thyroid CA?
chief cell hyperplasia
[diagnose]
woman (7th to 8th decade)
long standing neck mass
rapidly enlarging
anaplastic thyroid CA
most common type of of thyroid lymphoma
Non-hodgkin B cell type
Thyroid lymphoma usually arises from ___ thyroiditis
hashimoto
Regimen for thyroid lymphoma
RCHOP
Rituximab Cyclophosphamide Doxorubicin Vincristine Prednisone
most common malignancy that metastasize to the thyroid
renal cell CA