The document summarizes key information about the thyroid gland, including its anatomy, location in the neck, physiology, pathology, imaging modalities used for evaluation (ultrasound and nuclear medicine), biopsy procedures, and examples of thyroid cancers and cases. It describes the thyroid as a butterfly-shaped endocrine gland located in the front of the neck that produces hormones regulating metabolism. The document outlines the hypothalamic-pituitary-thyroid axis and common thyroid conditions like goiter, hyperthyroidism, hypothyroidism, and nodules. It also reviews ultrasound appearance of thyroid pathology and use of ultrasound-guided biopsy.

3. ANATOMY & LOCATION
 Brownish-red and soft during life.
 Butterfly shaped
 Endocrine Gland
 Divided into Right & Left lobes, connected by an Isthmus
 Located in the neck, medially and anterior to CCA (Common Carotid
Artery) and IJV (Internal Jugular Vein)
 Pyramidal lobe (normal variant): Superior extension of the Isthmus
 Contains follicles that contain a fluid called “Colloid”

4. Pyramidal lobe

5. PHYSIOLOGY
 Hypothalamus produces thyroid-releasing hormone
 Thyroid-releasing hormone controls the release of
Thyroid-stimulating hormone by the Pituitary gland
 Thyroid-stimulating hormone causes Thyroid to
release hormones in its cells.
1. Thyroxine (T4)
2. Triiodothyronine (T3)
3. Calcitonin

6. PHYSIOLOGY
 Thyrotropin “Thyroid-stimulating hormone” TSH:
Controlled by Pituitary gland
 Produces hormones called:
1. Thyroxine (T4): Aids in metabolism of fats, proteins, carbohydrates
2. Triiodothyronine (T3): Aids in metabolism of fats, proteins,
carbohydrates
3. Calcintonin: Removes calcium in the blood for storage in bones
 Uses Iodine, found in vegetables, seafood, and iodized salt to create these
hormones
 Regulates metabolism so your cells function properly
 Affects every cell in the body

7. Organs affected by Thyroid Hormones:
1. Eyes
2. Lungs
3. Heart
4. GI Tract
5. Liver
6. Uterus
7. Skin
8. Kidney
9. Brain

8. PATHOLOGY
 Goiter: Enlarged Thyroid gland
 Hyperthyroidism; Grave‟s disease
 Hypothyroidism; Hashimoto disease

9. PATHOLOGY
Goiter - Enlarged, hyperplastic thyroid gland:
 An Isthmus that is greater than 10mm indicates an enlarged Thyroid
 Thru Ultrasound, an enlarged Thyroid will appear Heterogenous w/
(multiple) cystic and solid components (Adenomatous goiter)

10. PATHOLOGY
Hyperthyroidism - Overproduction of Thyroid hormones
 Signs: Bulging eyes, Heat intolerance, Nervousness, Weight loss, Hair loss
 Thru Ultrasound, Thyroid will appear Heterogenous or Hypoechoic with
hypervascularity throughout the gland
 Grave‟s disease

11. PATHOLOGY
Hypothyroidism – Underproduction of Thyroid hormones
 Signs: Depression, Sensitive to cold, Elevated blood cholesterol levels, Slight weight gain
 Thyroid becomes inflamed, resulting in smaller amounts of thyroid hormones (causing the
Pituitary gland to produce more TSH)
 Thru Ultrasound, Thyroid will appear diffusely heterogenous, enlarged, vascular, with
hypoechoic nodules
 Hashimoto disease

12. PATHOLOGY
Benign Thyroid Nodules – Common masses, identified with sonography
 Considered as Follicular adenomas (most common benign neoplasms) or Hyperplastic
nodules (adenomatous nodules) are multiple and vary in sonographic appearance
 Characteristics: Cystic components, less than 5mm, hyperechoic mass, „eggshell‟
calcifications, „hot‟ (NM)

13. PATHOLOGY
Malignant Thyroid Nodules – Thyroid cancer
 Papillary carcinoma is the most common type of Thyroid cancer
 Other types: Follicular carcinoma, Medullary carcinoma, Anaplastic carcinoma,
lymphoma, thyroid metastases
 Characteristics: Hypoechoic mass, Mass with calcification, Solitary mass, Enlarged
cervical lymph nodes, irregular margins, internal vascularity of nodule, shape-taller than
wide, „cold‟ (NM)

14. PARATHYROID GLANDS, CERVICAL LYMPH NODES, OTHER NECK MASSES
 Parathyroid Glands – Located on the posterior of each lobe on the middle and inferior poles
1. Serve as calcium regulators, control the release and absorption of calcium by the PTH.
2. Hypocalcemia: Decreased levels of serum calcium
3. Hypercalcemia: Elevated levels of serum calcium
Pathology: Parathyroid Adenoma – Elevated Serum calcium and PTH
Sonographic Appearance - Hypo echoic mass near Thyroid
 Cervical Lymph Nodes – Can be found during routine neck sonography
1. Usually measure less than 1cm.
2. Oblong shaped, hypoechoic with echogenic hilum
Pathology: Cervical Lymphadenopathy - Enlarged cervical lymph nodes
Sonographic Appearance – Enlarged, greater than 1cm, Round, No echogenic hilum, Calficiations
 Other Neck Masses
1. Thyroglossal Duct Cyst: Benign congenital cyst. Superior to Thyroid, near Hyoid bone. Palpable
Sonographic Appearance: Anechoic, well-defined, unilocular, with posterior enhancement
2. Brachial Cleft Cyst: Benign congenital cyst. Found near angle of mandible. Palpable
Sonography Appearance: Anechoic

15. PARATHYROID GLANDS, CERVICAL LYMPH NODES, OTHER NECK MASSES

16. MODALITIES: NUCLEAR MEDICINE & SONOGRAPHY
 Nuclear Medicine - Nuclear medicine specialists use safe, painless, and cost-
effective techniques to image the body and treat disease. It provides doctors with
information about both structure and function. Nuclear medicine uses very small
amounts of radioactive materials (radiopharmaceuticals) to diagnose and treat disease.
Uses a 'gamma camera' to detect the radiation from the radioactive material.
 Sonography (Ultrasound) - With the use of a transducer that emits high-frequency
sound waves to produce relatively precise images of structures within your body.

17. MODALITIES: NUCLEAR MEDICINE & SONOGRAPHY

18. ULTRASOUND GUIDED: FINE NEEDLE ASPIRATION
 A type of biopsy procedure. In fine needle aspiration, a thin needle (attached to a syringe) is
inserted into an area of abnormal-appearing tissue or body fluid. It is then, the contents
suctioned out and the specimen are placed on slides and/or containers and sent off to a
pathologist for diagnosis.

19. PAPILLARY CARCINOMA – MEDULLARY CARCINOMA – FOLLICULAR CARCINOMA
ANAPLASTIC CARCINOMA – LYMPHOMA – THYROID METASTASES

20. REFERENCES
 Mosby’s Comprehensive Review for General Sonography
Examinations – Susanna Ovel
 Examination Review for Abdomen & Obstetrics and
Gynecology – Steven M. Perry

21. PATIENT CASES
Take from MDX patient files

22. PATIENT DEMOGRAPHICS
• 42 yr. old
• Female
• History of Thyroid nodule since 2009
• S/P FNAB 2009
• Latest Ultrasound study May 26,2012
• S/P FNAB March 3,2013

29. PATIENT DEMOGRAPHICS
• 44 yr. old
• Female
• Thyroid nodules found on the right lobe
• Latest Ultrasound study August 2012
• S/P FNAB November 2012

33. PATIENT DEMOGRAPHICS
• 82 yr. old
• Female
• Neck mass
• Hx thyroid cancer; papillary carcinoma
• S/P Thyroidectomy 2006 & Radiation therapy
• September 2006; palpable lump on neck Level IV

37. PATIENT DEMOGRAPHICS
• 39 yr. old
• Female
• Neck mass
• Hx RAI Uptake in right inferior thyroid bed
• S/P thyroidectomy 2010
• Considered for biopsy