1. Thyroid disease By
Dr Fahad

2. Anatomy of the Thyroid Gland

3. Location: ant neck at C5-T1, overlays 2nd – 4th tracheal rings
Average width: mm (each lobe)
Average height: mm long
Method of Imaging Investigation
Ultrasound
N/M
MRI/ CT

4. TC THYROID SCAN
NORMAL UPTAKE

5. THYROID ULTRASOUND NORMAL
0.99 X 1.07 CM
1.25 X 1.14 CM
3.75 X 1.16 CM
3.18 X 1.03 CM

6. THYROID COMPUTED TOMOGRAPHY
NORMAL
0.99 X 1.07 CM
3.75 X 1.16 CM

7. Thyroid Diseases
Thyrotoxicosis
Hypothyroidism
Thyroid nodules

8. Thyrotoxicosis VS Hyperthyroidism
Thyrotoxicosis: a group of symptoms and signs due to elevated thyroid hormones in the body of any cause.
Hyperthyroidism: a group of symptoms and signs due to increased production of thyroid hormones by hyper functioning thyroid gland.

9. Causes of Thyrotoxicosis
Hyperthyroidism
1- Diffuse toxic goiter (Graves’ disease)
2- Single toxic nodule
3- Toxic multi-nodular goiter
Early phase sub-acute thyroiditis
Exogenous thyroid hormone intake

10. Thyroid scan and uptake
Radioactive Iodine (RAI) is used for thyroid scan and uptake.
RAI is given orally.
Image and uptake are obtained after 24 hours
Follicular cell traps Iodine and organifys it to be incorporated with thyroid hormone.

11. Imaging findings Symmetric or asymmetric lobes.
Homogeneous or inhomogeneous uptake
Nodules; cold or hot

12. 24-hour RAI uptake
Measure photons in the given RAI by a special probe (uptake probe) just before taking RAI.
After 24 hours, measure photons in the neck (thyroid gland).
Calculate % of photons concentrated in thyroid gland.
Normal range of 24 RAI uptake is 10%- 30%

13. Increase uptake Hyperthyroidism Iodine starvation Thyroiditis
Hypoalbominemia
lithium

14. decrease uptake Hypothyroidism
Thyroid hormon therapy, PTU ,Lugol’s solution
Medication(contrast , multivitamins )
Thyroiditis

15. Diffuse Toxic goiter (Graves’ Disease)
Diffuse enlargement of thyroid gland.
Homogeneous uptake.
No significant focal abnormalities (nodules).
24-hour RAI uptake is elevated, usually > 35% (mean of 40%).

16. Graves’ Disease autoimmune disorder
presence of circulating antibodies directed at TSH receptors; stimulate the receptors
excessive thyroid hormone leads to hyperthyroidism
If you have Graves' disease, you may experience one or more of the following symptoms:
Nervousness; Irritability; Difficulty sleeping ; Rapid heartbeat ; Fine tremor of the hands or fingers ; Increased sweating ; Sensitivity to heat ; Sudden weight loss ; Bulging eyes ; Unblinking stare ; Goiter ; light menstrual periods ; Frequent bowel movements
unrelated tissue manifestations such as exophthalmos
In Graves' ophthalmopathy, the eyeball protrudes beyond its protective orbit (see graphic below) because tissues behind the eye attract and hold water. When this happens, the tissues and muscles swell, causing the eyeball to move forward in the orbit. The front surface of the eye can dry out. Eye symptoms and hyperthyroidism symptoms usually appear within 18 months of each other.
sometimes referred to as diffuse toxic goiter

17. Single Toxic Nodule
Single hot nodule (independent of TSH or autonomous).
Rest of thyroid gland is poorly visualized due to low TSH level (TSH dependant).
24-hour RAI uptake is slightly elevated, usually around 20%.

18. Multi-nodular Goiter
• Cut surface of one lobe of thyroid gland showing ill defined nodules. • Focus of cystic degeneration seen (blue arrow). • Some hemorrhage (red arrow) and some scarring.

19. Multi-nodular Goiter

20. Multi-nodular Goiter
6.75 X 3.16 CM
7.34 X 4.21 CM

21. THYROID COMPUTED TOMOGRAPHY
NORMAL
NODULES
0.99 X 1.07 CM
3.75 X 1.16 CM

22. Toxic Nodule

23. Hot Nodule

24. US images of thyroid nodule of varying parenchymal composition (solid to cystic).
US images of thyroid nodules of varying parenchymal composition (solid to cystic). (a) Sagittal image of solid nodule (arrowheads), which proved to be papillary carcinoma. (b) Sagittal image of predominantly solid nodule (arrowheads), which proved to be benign at cytologic examination. (c) Transverse image of mixed solid and cystic nodule (calipers), which proved to be benign at cytologic examination. (d) Sagittal image of predominantly cystic nodule (calipers), which proved to be benign at cytologic examination. (e) Sagittal image of cystic nodule (arrowheads). FNA of this presumed benign lesion was not performed because the nodule appears entirely cystic.
papillary carcinoma
Frates M C et al. Radiology 2005;237:
©2005 by Radiological Society of North America

25. US features of thyroid nodules
there is some overlap between the US appearance of benign nodules and that of malignant nodules
certain US features are helpful in differentiating between the two. These features include
micro-calcifications
local invasion
lymph node metastases
a nodule that is taller than it is wide
markedly reduced echogenicity.
Other features, such as the absence of a halo, ill- defined irregular margins, solid composition, and vascularity, are less specific but may be useful.

26. US Features Associated with Thyroid Cancer

27. Recommendations for Thyroid Nodules 1 cm or Larger in Maximum Diameter
Society of Radiologists in Ultrasound Consensus Conference Statement

28. Punctate echogenicities in thyroid nodules.
Punctate echogenicities in thyroid nodules. (a) Sagittal US image of nodule (arrowheads) containing multiple fine echogenicities (arrow) with no comet-tail artifact. These are highly suggestive of malignancy. FNA and surgery confirmed papillary carcinoma. (b) Transverse US image of nodule (arrowheads) containing cystic areas with punctate echogenicities and comet-tail artifact (arrow) consistent with colloid crystals in a benign nodule.
papillary carcinoma
Frates M C et al. Radiology 2005;237:
©2005 by Radiological Society of North America

29. US images of thyroid nodules of varying parenchymal composition (solid to cystic).
US images of thyroid nodules of varying parenchymal composition (solid to cystic). (a) Sagittal image of solid nodule (arrowheads), which proved to be papillary carcinoma. (b) Sagittal image of predominantly solid nodule (arrowheads), which proved to be benign at cytologic examination. (c) Transverse image of mixed solid and cystic nodule (calipers), which proved to be benign at cytologic examination. (d) Sagittal image of predominantly cystic nodule (calipers), which proved to be benign at cytologic examination. (e) Sagittal image of cystic nodule (arrowheads). FNA of this presumed benign lesion was not performed because the nodule appears entirely cystic.
papillary carcinoma
Frates M C et al. Radiology 2005;237:
©2005 by Radiological Society of North America

30. proved to be benign at cytologic examination
US images of thyroid nodules of varying parenchymal composition (solid to cystic).
US images of thyroid nodules of varying parenchymal composition (solid to cystic). (a) Sagittal image of solid nodule (arrowheads), which proved to be papillary carcinoma. (b) Sagittal image of predominantly solid nodule (arrowheads), which proved to be benign at cytologic examination. (c) Transverse image of mixed solid and cystic nodule (calipers), which proved to be benign at cytologic examination. (d) Sagittal image of predominantly cystic nodule (calipers), which proved to be benign at cytologic examination. (e) Sagittal image of cystic nodule (arrowheads). FNA of this presumed benign lesion was not performed because the nodule appears entirely cystic.
proved to be benign at cytologic examination
Frates M C et al. Radiology 2005;237:
©2005 by Radiological Society of North America

31. proved to be benign at cytologic examination
US images of thyroid nodules of varying parenchymal composition (solid to cystic).
US images of thyroid nodules of varying parenchymal composition (solid to cystic). (a) Sagittal image of solid nodule (arrowheads), which proved to be papillary carcinoma. (b) Sagittal image of predominantly solid nodule (arrowheads), which proved to be benign at cytologic examination. (c) Transverse image of mixed solid and cystic nodule (calipers), which proved to be benign at cytologic examination. (d) Sagittal image of predominantly cystic nodule (calipers), which proved to be benign at cytologic examination. (e) Sagittal image of cystic nodule (arrowheads). FNA of this presumed benign lesion was not performed because the nodule appears entirely cystic.
proved to be benign at cytologic examination
Frates M C et al. Radiology 2005;237:
©2005 by Radiological Society of North America

32. proved to be benign at cytologic examination
US images of thyroid nodules of varying parenchymal composition (solid to cystic).
US images of thyroid nodules of varying parenchymal composition (solid to cystic). (a) Sagittal image of solid nodule (arrowheads), which proved to be papillary carcinoma. (b) Sagittal image of predominantly solid nodule (arrowheads), which proved to be benign at cytologic examination. (c) Transverse image of mixed solid and cystic nodule (calipers), which proved to be benign at cytologic examination. (d) Sagittal image of predominantly cystic nodule (calipers), which proved to be benign at cytologic examination. (e) Sagittal image of cystic nodule (arrowheads). FNA of this presumed benign lesion was not performed because the nodule appears entirely cystic.
proved to be benign at cytologic examination
Frates M C et al. Radiology 2005;237:
©2005 by Radiological Society of North America

33. Role of color Doppler US
Role of color Doppler US. (a) Transverse gray-scale image of predominantly solid thyroid nodule (calipers).
Role of color Doppler US. (a) Transverse gray-scale image of predominantly solid thyroid nodule (calipers). (b) Addition of color Doppler mode shows marked internal vascularity, indicating increased likelihood that nodule is malignant. This was a papillary carcinoma.
papillary carcinoma
Frates M C et al. Radiology 2005;237:
©2005 by Radiological Society of North America

34. Role of color Doppler US
Role of color Doppler US. (a) Transverse gray-scale image of predominantly solid thyroid nodule (calipers).
Role of color Doppler US. (a) Transverse gray-scale image of predominantly solid thyroid nodule (calipers). (b) Addition of color Doppler mode shows marked internal vascularity, indicating increased likelihood that nodule is malignant. This was a papillary carcinoma.
papillary carcinoma
Frates M C et al. Radiology 2005;237:
©2005 by Radiological Society of North America

35. The lesion was benign at cytologic examination
Transverse US images of mostly cystic thyroid nodule with a mural component containing flow.
Transverse US images of mostly cystic thyroid nodule with a mural component containing flow. (a) Gray-scale image shows predominantly cystic nodule (calipers) with small solid-appearing mural component (arrowheads). (b) Addition of color Doppler mode demonstrates flow within mural component (arrowheads), confirming that it is tissue and not debris. US-guided FNA can be directed into this area. The lesion was benign at cytologic examination.
The lesion was benign at cytologic examination
Frates M C et al. Radiology 2005;237:
©2005 by Radiological Society of North America

36. US-guided FNA Technique
The needle may be introduced parallel or perpendicular to the transducer, and the needle tip should be carefully monitored during the procedure. 

37. US-guided FNA Technique
  Parallel positioning of the fine-gauge needle for thyroid nodule biopsy.
Figure 7a.  Parallel positioning of the fine-gauge needle for thyroid nodule biopsy. This positioning helps maximize the number of needle-generated reflected echoes perpendicular to the sound wave and is preferred by many operators. (a) Diagram shows insertion of the needle in a plane parallel to that of scanning. (b) US image, obtained with the transducer and needle positioned as in a, depicts the entire length of the needle (arrows) within the nodule.
Kim M J et al. Radiographics 2008;28:

38. Thank you