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Flashcards in ENDOC- THYROID Deck (64):
1

Describe the anatomy of the thyroid.

  • Paired lobes of near-equal size (5 × 2 × 2 cm)
  • connected by isthmus

2

Describe the parenchyma of thyroid.

Parenchyma: Homogeneous with fine medium-level echogenicity greater than that of the muscle.

 

3

The thyroid's anatomic landmarks are: 

Midline

 

Anatomic landmarks:

 

  • : air-filled trachea which casts an air shadow

4

The thyroid's anatomic landmarks are: 

 

Lateral edge:______________

 

 common carotid artery and internal jugular vein 

5

The thyroid's anatomic landmarks are: 

 

 

Posteriorly:________________
 

 longus colli muscles

6

The thyroid's anatomic landmarks are: 

 

 


Anteriorly:

  •  sternohyoid,
  • sternothyroid,
  • and sternocleidomastoid muscles

7

connected across the trachea by a thin thyroid______________

 

 isthmus

8

The thyroid lobes are often _______________ in size.

 

mildly asymmetric

9

The ______________- commonly protrudes from behind the trachea, nearly always on the left side, and must not be mistaken for a thyroid or parathyroid mass or lymph node (Fig.

esophagus

10

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11

In the UTZ of the Thyroid, what probe is used and why?

We use the LINEAR PROBE

Because Linear probe is used only for superficial organs and Thyroid is an example.

 

NOTE: The CURVE probe is used for deep seated organs.

12

What is the ◦First choice and the most sensitive imaging modality for thyroid?

§Ultrasound

 

Note : can give anatomical but not FUNCTIONAL

13


◦ provides excellent functional information about the thyroid gland
“Hot” or “Cold


Thyroid scintigraphy

 

Note:  Can give FUNCTIONAL but less of ANATOMICAL incontrast with UTZ

14

In thyroid scintigraphy:

HOT : 

DARKER

15

In thyroid scintigraphy,

COLD:

lighter

 

Nmemonics:  Hot place: DARKER people

Cold place: Lighter People

16

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Thyroid Hot and Cold Scintigraphy

17


 Extremely common:
◦4% to 8% of adults have palpable nodules
◦10% to 41% have nodules on US examination
◦50% have nodules at autopsy.
 Increase in frequency with age
 More common in women. 
 

Thyroid Nodules

18

How many percent of the adult have thyroid nodules?

4% to 8%

19

What gender is more common for Thyroid nodules?

Female

 

" Tandaan kasi baka dahil sa when going through pregnancy dba increase thyroid hormones.. baka lng.. link link hehe"

20

What are the parameters of Malignant Thyroid nodules?

  1. Iso- or HYPERechoic
  2. MACROcalcifications
  3. Regular border
  4. No infiltrative margins
  5. absent of abnormal cervical lymph nodes
  6. Periphery nodular vascularity

21

What are the parameters of malignant Thyroid nodules in UTZ?

  1. Hypoechoic
  2. Microcalcifications
  3. Border irregularity
  4. infiltrative margins
  5. abnormal cervical lymph nodes
  6. Increased intranodular vascularity

22

What are your BENIGN THYROID NODULES?


ØAdenomatous nodules
ØFollicular adenoma
ØThyroid cyst
ØHemorrhage
 

NMEMONICS: FATH

23

Thyroid cancer, on the other hand, affects only ____________ of the population.

Thyroid cancer is less than 1% of all cancer and is the cause of less than 0.5% of all cancer deaths.

Most thyroid cancers are slow growing and have low morbidity and mortality.

0.1%

24

 The ratio of benign thyroid nodules to thyroid cancer can be estimated at as high as ____________-.

The challenge of imaging studies and clinical evaluation is to establish the likelihood of malignancy and to select out for surgery only those patients with thyroid malignancy.

500:1

25

 select out for surgery only those patients with_________________

 thyroid malignancy.

26


 Colloid nodules
 Most common thyroid nodule.
 

Adenomatous Nodules

27

Adenomatous Nodules result from the_____________

 Growths resulting from cycles of hyperplasia and involution of thyroid tissue
 Multiple and associated with diffuse enlargement of the thyroid gland.
 

28

What are the imaging finding of Adenomatous Nodules?

 Imaging findings:
◦Isoechoic or hypoechoic to thyroid parenchyma
◦May show degenerative changes with prominent cystic components, necrosis, hemorrhage, and calcification
 

29

Q image thumb

dominant nodule (between arrowheads) with cystic change (arrow) measuring 18 mm in greatest dimension.

This nodule meets the Society of Radiologists in Ultrasound criteria for fine-needle aspiration (FNA).

US-guided FNA biopsy yielded a cytologic diagnosis of “colloid nodule” indicating visualization of benign thyroid cells and thyroid colloid.

Note the homogeneous pattern of the visualized normal thyroid parenchyma (Thy).

30


 Most common benign neoplasm
 Autonomous hyperfunctioning adenomas
◦Hyperthyroidism
 

Follicular Adenoma

31

What are the imaging finding of Follicular Adenoma?

 Imaging findings:
◦Most are solitary, solid, and well encapsulated.
Hypoechoic, hyperechoic, or isoechoic to thyroid parenchyma
Hyperfunctioning adenomas = strikingly hypervascular on Doppler US.
◦Degenerative changes
 

32

Hyperfunctioning adenoma appears ___________ on Doppler UTZ


◦Hyperfunctioning adenomas = strikingly hypervascular on Doppler US.

 

33

cause no alteration of overall thyroid function.

include focal necrosis, hemorrhage, edema, infarction, fibrosis, and calcification.

Differentiation from follicular carcinoma is difficult; therefore an ___________________________ is commonly considered an indication for surgical removal and histologic determination of the presence of cancer.

FNA cytologic diagnosis of follicular neoplasm

34

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Follicular Adenoma

 

Dominant thyroid nodule (between cursors, x, +) with an irregular area of cystic change is evident (arrow).

Because a diagnosis of follicular carcinoma could not be excluded, this lesion was surgically removed.

No histologic evidence

Differentiation from follicular carcinoma is difficult; therefore an FNA cytologic diagnosis of follicular neoplasm is commonly considered an indication for surgical removal and histologic determination of the presence of cancer.

35

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Follicular Adenoma

Showing hypervascularity

36

  • Extremely rare,
  • epithelial-lined,
  • simple cysts.
  • Cystic degeneration of an adenomatous nodule (“colloid cyst”) or a follicular adenoma.

Thyroid Cyst

37

Colloid Cyst

_______________Comet Tail Artifact.

A sharply defined cystic lesion within the right thyroid lobe shows floating punctate echogenic foci with a tapering tail (arrow).

This comet tail artifact is characteristic of inspissated colloid and a benign lesion.

38

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Colloid Cyst—Comet Tail Artifact. A sharply defined cystic lesion within the right thyroid lobe shows floating punctate echogenic foci with a tapering tail (arrow).

This comet tail artifact is characteristic of inspissated colloid and a benign lesion.

39

This comet tail artifact is characteristic of _______________

inspissated colloid and a benign lesion.

40


 May occur into an adenomatous nodule or a follicular adenoma, or spontaneously into normal parenchyma.
 Patients present with sudden neck pain and subsequent swelling.
 

Hemorrhage 

41

 Imaging Findings Of Hemorrhage in
 Ultrasound:

 hypoechoic nodule with internal debris.
 

42

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Ultrasound: hypoechoic nodule with internal debris.

43

Malignant Thyroid Nodules


§Papillary thyroid carcinoma
§Follicular thyroid carcinoma
§Medullary thyroid carcinoma
§Anaplastic thyroid carcinoma
§Others:
§Lymphoma
§Metastasis 
 

44

Among the malignant thyroid nodules this is the most common and comprises 75- 80 %


§Papillary thyroid carcinoma 
 

45

Follicular thyroid ca is %

10-20%

46

3-5 % of the malignant thyroid nodules is

Medullary  thyroid ca

47

 1-2% of malignant Thyroid nodules is


§Anaplastic thyroid carcinoma
 

48


 least aggressive cancers in human.
 Female (4:1)
 

Papillary Thyroid Carcinoma

49

What is the imaging finding in Papillary Thyroid Ca


 Imaging Findings:

  • ◦Nodules are hypoechoic and commonly multiple.
  • ◦Punctate internal calcifications (Psammoma bodies,42%)
  • ◦Characteristic parenhymal microcalcifications without a discrete mass present.
  • ◦Cervical nodes may contain similar calcifications. 
     

50

in papillary thyroid CA___________,42%) and highly indicative of malignancy

 

 Psammoma bodies

51

The Papillary thyroid CA tumor spreads commonly to regional nodes, but rarely ____________ spreads to lung or bone. Five-year survival is 95% to 99%.

(2% to 3%)

52

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Papillary Thyroid Carcinoma

 

Papillary Carcinoma of the Thyroid—Microcalcifications. Longitudinal image reveals a solid nodule containing numerous punctate nonshadowing echogenic foci characteristic of microcalcifications associated with papillary carcinoma indicative of malignancy. Biopsy proved papillary carcinoma.

53

 characteristic of microcalcifications associated with papillary carcinoma indicative of malignancy. Biopsy proved papillary carcinoma.

 solid nodule containing numerous punctate nonshadowing echogenic foci

54


 Slow-growing malignancy
 Blood vessels invasion = Characteristic!
 Hematogenous spread to lung and bone.
 Male gender and older age
 

Follicular Thyroid Carcinoma

55

What is the imaging finding of Follicular Thyroid CA?


◦Solitary, isoechoic, and ill defined.
◦Cystic areas, hemorrhage, and necrosis
Larger size, lack of an echolucent halo, hypoechoic appearance, and absence of cystic change

56

In Follicular Thyroid CA Clinical features that favor malignancy are ____________. Five-year survival is about 65%.cal nodes is uncommon.

 

male gender and older age

57

The sonographic features of follicular carcinoma

Features that favor carcinoma over adenoma include 

larger size, lack of an echolucent halo, hypoechoic appearance, and absence of cystic change

58

Microlcalcification of  > or =1 cm

Strongly consider US- guided FNA

59

Solid) almost entirely or with central calcification)

> or = 1.5 cm

Stongly consider US-guided FNA

60

Mixed solid and cystic or almost entirely cystic with a solid mural component

> or = 2 cm

Consider US- guided FNA

61

Substantial growth since prior US

ConsiderUS-guided FNA

62

Almost entirely cystic with none of the above and no substantial growth ( or no prior US) 

US-guided FNA probably not necessary

63

Multiple nodules

Consider US-guided FNA of one or more of the nodule selected by criteria listed for solitary nodules

64