3. Thyroid + Parathyroid Flashcards
Microcalcifications are supposed to be the buzzword fo
Papillary thyroid cancer
“Comet Tail” artifact is seen
Colloid nodules
This classificaiton have the highest accuracy, specificity, and positive predictive value for detecting malignancy
Microcalcification
Hallmark of papillary CA
Microcalcifciations
most common calcification in medullary CA
MACROcalcifications
Macrocalcifications in a single nodule =
Macrocalcifications in a multi-nodule goiter =
Macrocalcifications in a single nodule = High risk
Macrocalcifications in a multi-nodule goiter = Lower risk
Complete hypoechoic halo =
Highly suggestive of a benign disease
Irregular, spiculated, microlobulated margins =
Malignancy
Central pattern of flow =
Malignancy
Pure cystic, or spongiform with more than 50% specific =
Benign
Nodule size is NOT predictive of malignancy
True or False?
TRUE
Solid + Hyperfunctioning =
Thyroid adenoma
Female + Painflul gland + Hx of URTI =
Subacute Thyroiditis I De Quervains Thyroiditis
In Subacute Thyroiditis I De Quervains Thyroiditis, you eventually get
You get hyperthyroidism (from spilling the hormone) and then later hypothyroidism.
As you get over your cold, the gland recovers to normal function.
This is an actual bacterial infection of the thyroid. It is possible to develop a thyroid abscess in this situation.
Acute Suppurative Thyroiditis
Kids + Acute Suppurative Thyroiditis may be due to
start in a 4th branchial cleft anomaly (usually left) = travel via pyriform fistula = infection of the thyroid
Women in 40s-70s + IgG4 associated =
Reidels Thyroiditis
Reidels Thyroiditis
A sneak trick would be to show you a MR (it’s gonna be dark on all sequences - like a fibroma).
The most common congenital neck cyst in Pediatrics.
Thyrogiossai Duct Cyst (TGDC)
The thyroid is replaced by fibrous tissue and diffusely enlarges causing compression of adjacent structures (dysphagia, stridor, vocal cord palsy). On US there will be decreased vascularity.
Reideis Thyroiditis;
Thyrogiossai Duct Cyst (TGDC)
why care?
*They can get infected
*They can have ectopic thyroid tissue
*Rarely, that ectopic tissue can get papillary thyroid cancer (if you see an enhancing nodule)
Thyrogiossai Duct Cyst (TGDC)
This can occur anywhere between the foramen cecum (the base of the tongue) and the thyroid gland (or below). It looks like a thin walled cyst
Suprahyoid = 25% At the Hyoid = 30% Infrahyoid = 45%
The most common location of ectopic thyroid (90%)
Toungue
the rate o f malignant
transformation is rare (3%)
Autoimmune + causes hyperthyroidism (most common) =
Graves
It’s primarily from an antibody directed at the TSH receptor
Graves
Spares the tendon insertions, doesn’t hurt (unlike pseudotumor). Also has increased intra-orbital fat.
Graves Orbitopathy
most common cause of goitrous hypothyroidism
Hashimotos
It is an autoimmune disease that causes hyper then hypo thyroidism (as the gland bums out later).
Hashimotos
Hashimotos
Heterogeneous “giraffe sldn” appearance,
Hashimotos
White Knights - uniform hyperechoic nodules - which are actually regenerative nodules.
These are the nodes around the thyroid in the front ofthe neck.
Level 6 Nodes - “Delphian Nodes”
You can commonly see them enlarged with Hashimotos.
Level 6 Nodes - “Delphian Nodes”
a sick looking level 6 node - or “Delphian Node” is a>
Laryngal Cancer metastasis
There are 4 main subtypes of primary thyroid cancer.
- Papillary
- Follicular
- MEdullary
- Anaplastic
The Most Common Subtype of Thyroid CA
Papillary
Microcalcifications is the buzzword and key finding (seen in the cancer and nodes).
Papillary
Mets via the lymphatics. Has an overall excellent prognosis, and responds well to 1-131.
Papillary
The second most common subtype of Thyroid CA
Follicular CA
Mets hematogenously
to bones, lung, liver, etc.. Survival is still ok, (less good than papillary). Does respond to I-131.
Follicular CA
Association with MEN II syndrome + Calcitonin production =
Medullary Thyroid CA
Tendency towards local invasion, lymph nodes, and hematogenous spread.
Does NOT respond to 1-131.
Medullary Thyroid CA
Thyroid CA
Elderly + Hx of radiation treatment
Anaplastic
Rapid growth, with primary lymphatic spread. Does NOT respond to 1-131.
Anaplastic
Does not take up 1-131 as well as normal follicular. FDG-PET is the way to go for surveillance.
Hurthle Cell (variant of Follicular)
“microcalcifications in a node”
Thyroid metastasis
Metastasis on imageing
USD: hyperechoic
CT: Hyperenhancing
MR: bright T1
Classic pattern of pulmonary mets = miliary
How many parathyroid glands are located posterior to the thyroid?
4
This is by far the most common cause of hyperparathyroidism (90%).
Parathyroid Adenoma
Parathyroid Adenoma
4D C T shows early enhancement, and delayed washout
hypoechoic beans posterior to the thyroid.
Parathyroid Carcinoma
Uncommon
1% causes hyperparathyroidism
What are the causes of hyperparathyroidism?
Hyperfunctioning Adenoma (85-90%)
Multi-Gland Hyperplasia (8-10%)
Cancer (l-3%>).
What factors does sestamibi parathyroid imaging depend on ?
A: Mitochondrial density and blood flow
