Term
| Embryo origin of thyroid? |
|
Definition
| 1st and 2nd pharyngeal arches (not pouches?) |
|
|
Term
| Basic endocrine pathway for TSH release? |
|
Definition
Hypothal-->TRF
TRF-->Ant pit = TSH release
TSH -->thyroid = T3/T4 release via cAMP
T3/T4 negative feedback to hypothal/ant pit |
|
|
Term
| BS to thyroid/parathyroids? |
|
Definition
Sup thyroid (1st ECA branch) and Inf thyroid (thyrocerv. tr)
*Inf thyroid supplies both sup and inf parathy* |
|
|
Term
|
Definition
1% of population..
artery from inominate directly to isthmus |
|
|
Term
| where does thyroid venous drainage go to? |
|
Definition
sup and middle thyroid v--> IJ
Inf thyroid v -->innominate |
|
|
Term
| What does SUP lary n innervate? What is its course? |
|
Definition
motor to cricothyroid m
-runs lateral to thyroid lobes..tracks close to sup thyroid art
-has variable course |
|
|
Term
| MC nerve injury during thyroidectomy? |
|
Definition
|
|
Term
| Result of sup lary injury? |
|
Definition
| loss of projection, easy voice fatigability (singers) |
|
|
Term
| what is the innervation to larynx? |
|
Definition
Rec lary = motor to all of larynx except cricothyroid m
SUP lary = cricothyroid m |
|
|
Term
| what nerve controls vocal cords? |
|
Definition
|
|
Term
|
Definition
runs posterior to thyroid lobes in tracheo-esophageal groove
-often tracks with inf thyroid a (variable)
-Left loops Aorta
-Right loops innominate |
|
|
Term
|
Definition
unilat = hoarseness
bilat = airway obstruction -->EMERGENCY TRACH |
|
|
Term
| % of pop with non-rec lary nerve? |
|
Definition
|
|
Term
|
Definition
posterior medial suspensory ligament
-close to RLNs |
|
|
Term
|
Definition
15:1
T3 = more active
Most T3 produced by T4 conversion in the periph by de-iodinases |
|
|
Term
| What enzyme links vs separates iodine and tyr? |
|
Definition
peroxidases = link
deiodinases separate |
|
|
Term
| most sensitive marker of thyroid function? |
|
Definition
|
|
Term
| what are tubercles of Zuckerkandl? |
|
Definition
most lateral, posterior extension of thyroid tissue
-rotate them medially to find REC lary
-left behind with subtotal thyroidectomy due to proximity to RLN |
|
|
Term
| What produces calcitonin? What does calcitonin do? |
|
Definition
parafollicular C cells
-lowers Ca |
|
|
Term
| What is appropriate TSH response to thyroixine tx? |
|
Definition
TSH levels fall by 50%
-osteoP is long term SE |
|
|
Term
| Mgmt of post thyroidectomy stridor? |
|
Definition
open neck-->remove hematoma if due to bleeding
-->emergent trach if due to RLN injury |
|
|
Term
|
Definition
| high output cardiac failure |
|
|
Term
| MC scenario for thyroid storm? |
|
Definition
| post-op pts with undiagnosed graves DZ, |
|
|
Term
|
Definition
BBLK first line
-ccol pt, O2, glucose
Lugol's soln = KI solution (takes time to work) |
|
|
Term
| Wolff-Chaikoff effect = ? |
|
Definition
give high doses of iodine (KI lugols soln)
-->inhibit TSH action on thyroid = less T3/T4 release |
|
|
Term
| % of thyroid nodules that are benign? |
|
Definition
|
|
Term
| Best test for thyroid nodule? |
|
Definition
FNA best first test
-80% are determinant
-if show follicular cells.. must do lobectomy (10% CA risk) |
|
|
Term
| Mgmt of cyst fluid on initial thyroid FNA? |
|
Definition
| bloody or recurrent ==> lobectomy |
|
|
Term
| mgmt FNA showing colloid tissue? |
|
Definition
likely colloid goiter. 1% malig risk
-tx thyroixine |
|
|
Term
| Tx for symptomatic toxic thyroid nodule? |
|
Definition
|
|
Term
| mgmt of indeterminant FNA of thyroid nodule? |
|
Definition
Radionucleotide study
-Hot and sxs? methimazoe/I131
-cold = lobectomy (inc Ca % vs hot) |
|
|
Term
| Tx of cold vs toxic goiter? |
|
Definition
cold = thyroixine
toxic = NO thyroxine (methimazole and I 131 if sxs) |
|
|
Term
Primary vs secondary substernal goiter
-blood supply |
|
Definition
most are secondary (BS from sup/inf thyroid a)
Primary = rare = BS from innominate art |
|
|
Term
| source of mediastinal thyroid tissue? |
|
Definition
| most from acquired disease with inferior extension of normally located thyroid (substernal goiter) |
|
|
Term
|
Definition
10%
= extension from isthmus toward the thymus |
|
|
Term
| Malig risk of lingual lobe? |
|
Definition
|
|
Term
| what is lingual thyroid lobe? |
|
Definition
| thyroid tissue that persists at base of tongue at foramen cecum |
|
|
Term
|
Definition
dysphagia
dyspnea
dysphonia |
|
|
Term
|
Definition
thyroxine suppression, abolish w/I 131
-resection if worries about CA (2% malig) or doesnt shrink with medical tx
-NOTE: in 70% of lingual lobe pts, it is their only thyroid tissue |
|
|
Term
thyroglossal duct cyst
-location
-associated risks
-tx |
|
Definition
-midline cervical mass between hyoid and thyroid isthmus
-moves upward with swallowing
-risks = infection, malig, dysphonia
-tx w/resection (take midportion of hyoid bone with the cyst) via sistrunk procedure w/lateral neck incision |
|
|
Term
hyperthyroid tx
-first line drug? Contraindication? |
|
Definition
-1st = methimazole. Contrain @ pregnancy
-->mech = peroxidase inhibitor prevents coupling I-Tyr |
|
|
Term
|
Definition
cretinism in newborns (crosses placenta)
aplastic anemia
agranulocytosis |
|
|
Term
PTU
-main SE
-main indication |
|
Definition
-SE = hepatoTOX, aplastic anemia, agranulocytosis
-used in pregnancy |
|
|
Term
|
Definition
@ poor surgical pts unresponsive to methimazole
-CANNOT use in children/pregnancy (crosses placenta) |
|
|
Term
| basic indications for thyroidectomy (outside of CA) |
|
Definition
-cold nodules
-toxic adenoma
-graves not controlled with meds
-preggers not controlled with PTU
-compressive goiter
-toxic multinodular goiter |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
| exopthalmos, pretibial edema, AFib, heat intolerance, inc thrist, inc hunger, weight loss, sweaty, palpitations |
|
|
Term
|
Definition
| exopthalmos, pretibial edema |
|
|
Term
|
Definition
IgG Ab to TSH receptor (LATS = long acting thyroid stimulator)
(TSI = thyroid stim immunoglobulin) |
|
|
Term
|
Definition
-Dec TSH
-Inc T3/T4
-Inc LATS level
-diffuse increase of I uptake on thyroid scan |
|
|
Term
| mgmt /success rate of Graves mgmt? |
|
Definition
medical therapy = 95% success
-thioamides (50% recurrence)
-I 131 (5% recurrence)
-thyroidectomy of failed medical mgmt
(bblk only help sxs) |
|
|
Term
| MC reason to operate on graves? |
|
Definition
rarey needed as medical mgmt 95% success
-MC indication = suspicious nodule |
|
|
Term
| pre-op prep for thyroidectomy vs Graves? |
|
Definition
-methimazole until euthyroid
-THEN, once euthyroid...BBLk, Lugols soln x 14 days (decreases vascularity/friability)
-bilateral subtotal (5% recurrence) vs total (lifetime thyrox)
- |
|
|
Term
| Indications for OR vs Graves? |
|
Definition
non-compliant pt
failed medical mgmt
pregger not controlled with PTU
suspicious nodule (MC indication) |
|
|
Term
| Cause of toxic multinodular goiter? |
|
Definition
| hyperplasia 2/2 hronic low grade TSH stim |
|
|
Term
| Histo of toxic multinodular goiter? |
|
Definition
|
|
Term
| Tx options for toxic multinod goiter |
|
Definition
1st = surgery
-trial of 131-I considered esp in poor surg candidates |
|
|
Term
|
Definition
|
|
Term
| MCC hypothyroid in adults? |
|
Definition
|
|
Term
|
Definition
Enlarged gland
painless
chronic thyroiditis (can cause thyrotoxicosis @ acute early stage) |
|
|
Term
|
Definition
female
hx of childhood XRT |
|
|
Term
| Pathyophys /origin of hashimotos? |
|
Definition
| humeral and cell mediated AI DZ (microsomal and thyroglobulin Ab) |
|
|
Term
| Why do pts get goiter with hashimotos? |
|
Definition
| lack of organification of trapped Iodide inside gland |
|
|
Term
| findings on path/histo for hashimotos? |
|
Definition
|
|
Term
|
Definition
thyroxine first line
-partial thyroid if refractory/nodule/compression |
|
|
Term
| MCC bacterial thyroiditis? |
|
Definition
continguous spread from bacterial URI (staph/strep
tx abx |
|
|
Term
De-Quervains thyroiditis
-cause?
-pres?
-marker? |
|
Definition
-Viral URI precursor
-Tender, sore throat with mass, weakness, fatigue. W>M
-Elevated ESR |
|
|
Term
De-Quervains thyroiditis
-tx |
|
Definition
steroids + ASA
-possible lobectomy if unilateral and cant r/o CA
-possible total thyroidectomy if persistent |
|
|
Term
Reidel's fibrous struma
-presenataion/appearance
-w/u and dx
-sxs
-assoc conditinos? |
|
Definition
-hypothyroid and compressive sxs. Woody/fibrous componenet that involves adjacent strap muscles/carotid sheath
-Bx to r/o CA/lmphoma
-a/w sclerosing cholangitis, fibrotic dz, methysergide Tx, RP fibrosis |
|
|
Term
| Riedels fibrous struma tx |
|
Definition
steroids + thyroixine
-possible isthmectomy/trach if airway sxs |
|
|
Term
| chance of malignancy with follicular cells on FNA? |
|
Definition
| 5-10% (cant differentiate based on vs adenoma/hyperplasia/Ca) |
|
|
Term
| FNA findings worrisome for CA? |
|
Definition
solid, solitary, slow growing,
cold, hard
male, age> 50
hx XRT, MEN 2a/b |
|
|
Term
|
Definition
papillary
-least aggressive, slow growing, best prog
-MC women, children |
|
|
Term
RF for papillary ca?
RF for worse prog? |
|
Definition
childhood neck XRT = inc risk
age >40-50 = worse prog |
|
|
Term
| what determines papillary CA prog? |
|
Definition
local invasion
(lymph spread occurs first, but is not prognostis)
RARE mets to lung |
|
|
Term
| MC population with node +ve pap CA? |
|
Definition
children (80% vs adults 20%)
often multicentric dz |
|
|
Term
|
Definition
psammoma bodies (calcium)
Orphan annie nuclei |
|
|
Term
|
Definition
95%
MC death = local disease |
|
|
Term
Follicular thyroid CA
-route of mets/ MC met location?
% metastatic at dx?
-5YSR? |
|
Definition
-hematogenous to bone MC
-50% met at Dx
-70% (prog based on stage) |
|
|
Term
pap/follic CA
-indications for total thyroidectomy? |
|
Definition
-tumor > 1 cm
-extra-thyroidal dz (past capsule, nodes, met)
-multi-centril, bilateral
-hx XRT |
|
|
Term
pap/follic CA
-indications for MRND |
|
Definition
|
|
Term
pap/follic CA
-indications for post-op 131? |
|
Definition
-tumor > 1 cm
-extra thy dz
(need total thy for i 131 to work. Give 6 weeks after surg to maximize TSH uptake) |
|
|
Term
pt has enlarged lateral neck LN.. path shows thyroid tissue.
-Dx
-Tx |
|
Definition
-dx = pap thyroid CA with lymph spread
-total thy, MRND, i 131 |
|
|
Term
| RF for thyroid CA recurrence/mets? |
|
Definition
X-GAMES
XRT, high Grade, Age (<20 or >50), Male, Extra-thy dz, Size >1 cm |
|
|
Term
| gene a/w medullary thyroid CA? |
|
Definition
RET proto-oncogene (Men 2a/b)
-usually first manifestation of MEN (Diarrhea from calcitonin) |
|
|
Term
| % of medullary CA that are sporadic? |
|
Definition
|
|
Term
| Origin of medullary CA cells? |
|
Definition
|
|
Term
| premalig medullary CA lesion? |
|
Definition
|
|
Term
|
Definition
|
|
Term
| sxs of calcitonin increase with medullary CA? |
|
Definition
|
|
Term
| other tests needed after medullary CA is diagnosed? |
|
Definition
| screen for hyperparathyroidism and pheochromocytoma |
|
|
Term
|
Definition
lymphatic (most have met at dx)
-early mets to lung, liver, bone |
|
|
Term
| medullary CA factors for worse prog? |
|
Definition
| a.w MEN 2b, and sporadic types |
|
|
Term
|
Definition
total thy
CENTRAL neck node dissection
-MRND if palpable mass
-bilateral MRND if bilateral tumor OR if extrathyroidal dz |
|
|
Term
| indication for prophy total thyroidectomy/dissection? |
|
Definition
MEN 2a @ 6 years old
MEN 2b @ 2 years old |
|
|
Term
| monitor for recurrence of Medullary CA? |
|
Definition
calcitonin levels
best test = pentagastrin-stimulated peak plasma calcitonin levels |
|
|
Term
|
Definition
|
|
Term
| % hurthle cell CA that are benign? |
|
Definition
| 80% benign (Hurthle adenoma) |
|
|
Term
| hurthle cell met location? |
|
Definition
|
|
Term
| histopath of hurthle cell CA? |
|
Definition
|
|
Term
| FNA shows hurthel cell CA.. next step? |
|
Definition
| lobectomy (cant differentiate malig vs benign with FNA) |
|
|
Term
|
Definition
| total thyroid w/MRND if + nodes and malignant (20% are malig) |
|
|
Term
| histo-path anaplastic thyroid CA? |
|
Definition
| vesicular appearing nuclei |
|
|
Term
| 5ysr anaplastic thyroid CA? |
|
Definition
|
|
Term
| tx anaplastic thyroid CA? |
|
Definition
usually non-resectable at presentation
-palliate thyroid/ chemo-xrt for compressive sxs |
|
|
Term
| which thyroid CA are amenable to XRT? |
|
Definition
| papillary, follicular, medullary, hurthle cell CA |
|
|
Term
| which thyroid CA are amenable to I-131? |
|
Definition
| papillary and follicular ONLY |
|
|
Term
when to give I 131 for CA?
when not to? |
|
Definition
4-6 weeks post-op when TSH levels are highest (no thyroid replacement until AFTER I-131 treatment)
-don't give @ children, pregnancy, lactating mothers (cretinism)
*can cure bone and lung mets* |
|
|
Term
| I 131 indications for papillary/follicular thyroid CA? |
|
Definition
recurrent CA
inoperable tumors due to local invasion
tumors > 1 cm / extra-thyroidal
mets: need total thyroid first otherwise I-131 will just be taken up by thyroid and not mets |
|
|
Term
|
Definition
| rare-->sialoadenitis, GI sxs, infert, BMarrow suppression, parathyroid dysfunction, leukemia |
|
|
Term
|
Definition
help suppress TSH and slow metastatic dz
-only give after I-131 therapy is over |
|
|
Term
| origin of thyrotropin releasing hormone? |
|
Definition
TRF->
paraventricular nucleus of hypothal
(stims TSH and prolactin release from ant pit) |
|
|
Term
| next step after benign FNA bx? |
|
Definition
|
|
Term
| myxedma coma presentation? |
|
Definition
hypothy, hypocortisol, hypoglycemia, hypovent, hypothermia
hypoTN, hypoventilation.
Infxn |
|
|
Term
| what is the papillary thyroid CA tumor marker? |
|
Definition
|
|
Term
| Markers for medullary thyroid CA? |
|
Definition
Carcinoembryonic antigen (CEA)
Calcitonin |
|
|
Term
|
Definition
|
|
Term
|
Definition
intersection with inf thyroid artery (unless its non-recurrent)
-inf thy art tracks upwards behind the carotid, then medially to the thyroid. |
|
|
Term
| most common XRT induced thyroid CA? |
|
Definition
|
|
Term
| best indication for minimally invasive thyroid surgery? |
|
Definition
| benign, unilateral dz in pts without prior surgery |
|
|
Term
| US findings suspicious for thyroid CA? |
|
Definition
microcalcs,
heterogenous and HYPOechoic interiors
irregular margins
dimensions taller than they are wide (benign lesions grow radially) |
|
|
Term
| age of medullary thyroid CA presentation in MEN pts? |
|
Definition
|
|
Term
|
Definition
path finding on papillary thyroid CA
(also calcifications, overlapping and clear nuclei = annie) |
|
|
Term
| course after rec lary injury? |
|
Definition
most are asympt or minimally symptomatic
-most recover 3-6 mo
-->if not..get direct laryngoscopy |
|
|
Term
| how does pH affect Ca levels? |
|
Definition
| alkalosis = inc binding of Ca to albumin = dec iCal |
|
|
Term
| Ca content of Ca gluconate vs Calcium chloride? |
|
Definition
gluconate = 90 mg (4.5 mEq)
Chloride = 270 mg (13.5 mEq) |
|
|
Term
| age and indication for thyroid surgery? |
|
Definition
men over 60-->excise all thyroid nodules
(risk of thyroid nodule being malig inc to 50% at 70 y.o male) |
|
|
Term
| Genetic mutations and their associated thryoid CA? |
|
Definition
BRAF-V600 = papillary
PAX-8/PPARgamma = follicular
RET = medullary
p53 = anaplastic |
|
|
Term
| mgmt of papillary CA mets to nodes? |
|
Definition
if only micro-mets....don't do lymph node dissection
-if grossly enlarged etc..then take them |
|
|
Term
| which side is rec lary more variable on? |
|
Definition
right side (often run more lateral)
-thus left neck approach safer |
|
|
Term
| consequence of rec lary injury and resultant location of vocal cord? |
|
Definition
ADduct = airway osbtruction, stridor (nothing if unilat ADduct)
ABduct = aspriation if bilateral (hoarse if unilaterl abduct) |
|
|
Term
| intra op rec lary injury..next step? |
|
Definition
|
|
Term
| associated anomaly with non rec lary? |
|
Definition
MC on right side
-a/w aberrant right SCA off the descending aorta |
|
|
Term
|
Definition
| via thyroglobulin as colloid |
|
|
Term
| what carries most of peripheral thyroid hormone? |
|
Definition
|
|
Term
| FNA shows complex cyst..next step? |
|
Definition
| lobectomy (Papillary CA can present as complex cyst) |
|
|
Term
|
Definition
| 6 weeks thyroixn (will dec TSH and nodule will go away) |
|
|
Term
| Thyroid lymphoma markers that predict worse prog? |
|
Definition
LDH
Beta-2 microglobulin
tx Chemo +/- XRT
(a/w hashimotos) |
|
|
Term
| Pap thy CA that doesn't need total thyroidectomy? |
|
Definition
|
|
Term
| goal level of TSH after I 131 tx? |
|
Definition
< 0.03
achieve with synthroid |
|
|
Term
| papillary CA recurrence monitoring? |
|
Definition
thyroglobulin level
I-123 for late recurrence |
|
|
Term
enlarged laterl neck LN with bx showing normal thyroid tissue...
Dx
Tx |
|
Definition
pap thyroid CA with lymphatic spread
tx total thy, ips MRND, i 131 |
|
|
Term
| follicular prognosis factors? |
|
Definition
hematogenous AND LN spread
(in contrast to papillary which is based on local invasion) |
|
|
Term
MTC
-cell origins
-stim test? |
|
Definition
neural crest cells
-hyperplasia is premalig
-gastrin stim test = inc calcitonin |
|
|
Term
|
Definition
|
|
Term
| 5YSR for MTC pts p/w palpable mass? |
|
Definition
50% MEN 2a
10% MEN 2b (B = BAD) |
|
|
Term
| boundaries of central neck dissection? |
|
Definition
-IJ to IJ
-up to hyoid
-down to innominate |
|
|
Term
| anaplastic thyroid ca histo? |
|
Definition
|
|
Term
|
Definition
Papillary or follicular Ca only AND
-> 1 cm
-extrathyroidal dz
-recurrence |
|
|
Term
|
Definition
|
|
Term
| DDx hyperthyroidism (6 causes) |
|
Definition
Graves (older F)
Toxic adenoma (younger F)
Toxic multinodular goiter
Thyroiditis
TSH secreting tumor (rare)
Struma ovarii
Amiodarone (hyper or hypo) |
|
|
Term
| hyperthyroid dx based on Thyroid scan (RAIU)? |
|
Definition
increased and
-homogenous and diffuse = Graves
-heterogeneous and diffuse = toxic multi nodular goiter
-local uptake = hot nodule |
|
|
Term
| Recurrence rate of hyperthy after medical vs treatment? |
|
Definition
PTU/methimazole = 50%
I-131 = 5% vs graves/adenoma. higher for multinodular dz (inhomogenous uptake)
-subtotal = 5% (good for multinodular ) |
|
|
Term
| Mgmt of pregnant pt with hyperthyroid? |
|
Definition
1. PTU utnil 2nd trimester, w/BBLK vs sxs
2. if refractory..OR in 2nd trimester (inc still birth if wait til 3rd)
*I-131 crosses placenta and destroys fetal thyroid->cretinism
*BBLk in 3rd tri = growth retardation |
|
|
Term
| why not use I 131 in children? |
|
Definition
|
|
Term
| what can get worse with I 131? |
|
Definition
exophthalmos
-tx steroids, XRT, surg orbit decompression |
|
|
Term
| PTU /methimazole mechanism? |
|
Definition
inhibits peroxidases
-PTU also blocks periph conversion (deiodinases) |
|
|
Term
| Acute mgmt of thyroid storm? |
|
Definition
BBLK (esmolol gtt)
PTU
Lugols (1 hr after PTU) = Wolff-Chaikoff effect
cooling blankets
O2, glucose,
Steroids (cortisol 100 q8) |
|
|
Term
| what is wolf-chaikoff effect? |
|
Definition
| High dose Iodine inhibits TSH action on thyroid and inhibits coupling |
|
|
Term
|
Definition
non-toxic, multinodular colloid goiter
MCC iodine deficiency |
|
|
