DMS 221 - WB Ch. 15 (Thyroid, Parathyroid & Neck)
The echotexture of the normal thyroid gland is _____, and _____ when compared to the adjacent musculature.
-homogeneous -hyperechoic
What are typical symptoms of Graves dx?
-hyperthyroidism -elevated levels of T3 & T4 -bulging of the eyes (NOT a typical symptom - shrunken, echogenic thyroid gland)
A condition that is associated w/ excessive release of thyroid hormones is called _____, whereas one associated w/ a thyroid hormone deficiency is referred to as _____.
-hyperthyroidism -hypothyroidism
Malignant thyroid nodules are typically solid & _____ when compared to the normal thyroid parenchyma.
-hypoechoic
Maintenance of the concentrations of T3 & T4 is controlled by a regulatory system that involves the _____, the _____ and the thyroid gland.
-hypothalamus -pituitary
What is the most common functional disorder of the thyroid gland?
-hypothyroidism
What are characteristics of a metastatic lymph node?
-increasing size on serial exams -microcalcifications -rounded, bulging shape (NOT - prominent fatty hilum)
Which type of thyroid cancer is seen in pts w/ a personal hx of multiple endocrine neoplasia type 2 syndrome?
-medullary carcinoma
The presence of _____ is one of the most specific sonographic feature of thyroid malignancy. They are commonly found in _____ thyroid cancer.
-microcalcifications -papillary
Which characteristic increase the suspicion of malignancy in a thyroid nodule?
-microcalcifications (does NOT increase suspicion - eggshell calcifications, hyperechogenicity, peripheral calcifications)
On a sono exam, your pt presents w/ an enlarged, heterogeneous thyroid gland. The pt's lab work is normal, and pt is not experiencing any symptoms besides the palpable enlarged gland. What is most likely the diagnosis?
-multinodular goiter
A nontoxic goiter refers to an enlargement of the entire gland w/out evidence of discrete _____ and without _____ disturbance. Simple goiters may convert into _____ goiters, demonstrated by a multilobulated, asymmetrically enlarged gland.
-nodularity -functional -multinodular
What is the most common form of thyroid cx?
-papillary
While performing an exam of the thyroid, a small, oval, homogeneously hypoechoic mass is seen posterior to the mid-lateral lobe of the thyroid gland. This appears to be separate from the thyroid gland. What is the most likely diagnosis?
-parathryoid adenoma
What is the most common cause of hyperparathyroidism? Clinical symptoms?
-parathyroid adenoma (80-85%) -parathyroid hyperplasia (10-15%) -symptoms: elevated serum calcium levels, weight loss, dyspepsia, peptic ulcer dx, renal colic, kd stones, bone & joint pain & gout
The parathyroid glands are responsible for producing _____ which regulates the concentrations of _____ and _____.
-parathyroid hormone -calcium -phosphorus
The CCA and IJV form the _____ border of the thyroid gland. The _____ muscle is seen posterior to the gland.
-posterior lateral -longus colli
What is the main function of the thyroid gland?
-regulation of the basal metabolic rate
The _____ & _____ thyroid veins drain into the IJV, whereas the _____ thyroid veins drain into the brachiocephalic veins.
-superior -middle -inferior
The thyroid gland receives a rich blood supply from four arteries: the paired _____, which arise from the external carotids, and the _____, which originate at the thyrocervical trunk of the subclavian artery.
-superior thyroid arteries -inferior thyroid arteries
Congenital cysts of the neck include _____, which tend to be midline, and _____, which tend to lie lateral to the carotid artery.
-thyroglossal duct cyst -brachial cleft cysts
You are asked to evaluate the parathyroid glands during a sono exam of the neck. What landmarks will you use to locate the parathyroid glands?
-typically located between the posteromedial thyroid gland and the longus colli muscle -superior glands are slightly more medial than inferior glands -they should lie medial to the cca, posterior to the lateral lobe & anterior to the longus colli
What are characteristics of benign thyroid nodules?
-uniform hypoechoic halo -avascularity -well-defined, regular margins (NOT - taller-than-wide shape)
indolent
causing little pain or slow growing
thyroglossal duct cyst
congenital anomaly located anterior to trachea, extending from the base of the tongue to the isthmus of the thyroid
hyperparathyroidism
disorder associated w/ elevated serum calcium levels, usually caused by benign parathyroid adenoma
adenopathy
enlargement of the glands
Sternocleidomastoid is a strap muscle. T/F
false
The trachea forms the lateral border of the thyroid gland. T/F
false
goiter
focal or diffuse thyroid gland enlargement due to iodine deficiency
parathyroid hormone
hormone produced by the parathyroid glands that regulates serum calcium and phosphorus
thyroid-stimulating hormone
hormone secreted by the anterior pituitary gland that stimulates the thyroid gland to secrete T4 & T3
microcalcifications
hyperechoic foci that may or may not shadow
Fine-needle aspiration is NOT effective for diagnosing which form of thyroid carcinoma?
-follicular carcinoma
The most common cause of primary hypothyroidism is _____.
-hashimoto thyroditis
Which transducer would be appropriate for evaluation of the thyroid gland & neck on an avg pt?
-12 MHz linear array
Papillary carcinoma most common occurs between the ages of _____, and it is three times more common in _____.
-20-50 -women
How many parathyroid glands to most adults have?
-4
Most adults have _____ parathyroid glands: two _____ located posterior to the mid-portion of the thyroid gland and two _____ located in a more variable position.
-4 -superior -inferior
The mean length of the thyroid gland is _____ mm, mean AP diameter is _____ mm & mean thickness of the isthmus is _____ mm.
-40-60 mm -12-18 mm -4-6 mm
The majority of pts w/ hyperthyroidism have _____ disease, which is an _____ disease.
-Grave's -autoimmune
What is the most common cause of primary hypothyroidism? Clinical symptoms?
-Hashimoto thyroiditis -cold intolerance, constipation, weight gain, dry skin, muscle aches, headaches
A radioiodine scintigraphy exam can be use to evaluate thyroid nodules. What statements are true regarding this exam?
-Nodules may be classified as either hot or cold -A hot nodule traps an excessive amt of isotope & is hyperfunctioning -A cold nodule does not absorb the isotope & demonstrates an area of decreased or absent activity (FALSE - all cold nodules are malignant)
Describe the technique used to perform a fine-needle aspiration of a suspicious thyroid nodule.
-Sterile technique; 25-gauge needle is guided into the thyroid nodule using US -a syringe is used to create mild suction OR the capillary action of the need alone can be used -needle is repeatedly moved back and forth w/in the nodule to collect cells and tissue -cells/tissue submitted for cytological eval
The thyroid gland secretes three hormons: _____, _____, & _____ is needed to properly synthesize the hormones.
-T3 -T4 -calcitonin iodine
_____ is a hypermetabolic state caused by elevated levels of free _____ & _____.
-Thyrotoxicosis -T3 -T4
Primary hyperplasia is enlargement of _____ and should be expected when _____ nodules are identified, whereas ______ should be suspected when a solitary nodule is identified.
-all four glands -multiple -parthyroid adenoma
Which aggressive form of thyroid cancer has a tendency to compress & destroy the local structures of the neck?
-anaplastic carcinoma
adenoma
-benign solid tumor
Causes & clinical symptoms of hyperthryoidism
-causes: Grave's dx, toxic multinodular goiter, hyperfunctioning thyroid nodules, follicular thyroid carcinoma, thyroiditis -symptoms: increased cardiac output, tachycardia, loud heart sounds, goiter, weight loss, n/v, excessive sweating, flushing, heat intolerance, hair loss, restelssness
A pt presents for evaluation of the thyroid gland w/ a hx of Hashimoto thyroiditis. What are common symptoms of this condition?
-cold intolerance -menstrual irregularities -fatigue (NOT a common symptom - weight loss)
The thyroid is an _____ gland that is made up of a _____ and _____ lobe, connected by a thin _____ of tissue.
-endocrine -right -left -isthmus
The thyroid & parathyroid both have what common function?
-endocrine glands
Thyroid adenomas are benign nodules contained w/in a _____. A minority of adenomas are toxic and cause _____. Typically, and adenoma will demonstrate a _____ surrounding the nodule. Sonographically, large adenomas have the characteristics of a _____.
-fibrous capsule -hyperthyroidism -hypoechoic halo -complex cyst
A definitive diagnosis of papillary carcinoma can be made by _____. The overall survival rate of this type of thyroid cancer is _____%, making it the least aggressive form of thyroid cancer.
-fine needle aspiration -98%
cold nodule
area seen on nuclear medicine study as a region of thyroid where the radioisotope has not been taken up
graves disease
an autoimmune hyperthyroidism caused by antibodies that continuously active TSH receptors
thyroid inferno
increase in color doppler vascular flow in the thyroid
thyroiditis
inflammation of the thyroid
fine-needle aspiration
invasive procedure using a small gauge needle to obtain a tissue specimen from a specific lesion
sternocleidomastoid muscles
large muscles located anterolateral to the thyroid
anaplasia
loss of differentiation of cells, which is characteristic of tumor tissue
hypophosphatasia
low phosphatase level that can be seen with hyperparathyroidism
papillary carcinoma
most common form of thyroid cancer
Hashimoto thyroiditis
most common inflammatory disease of the thyroid gland
heterotopic
occurring at an abnormal place upon the wrong part of the body
primary hyperparathyroidism
oversecretion of parathyroid hormones
What is the most common cause of primary hyperparathyroidism?
parathyroid adenoma
strap muscles
sternohyoid & sternothyroid muscles located anterior to the thyroid
isthmus
the band of thyroid tissue connecting the rt & lf lobes
euthyroid
thyroid gland is producing the right amount of thyroid hormone
hypothyroidism
under-active thyroid hormones
longus colli muscles
wedge-shaped muscle posterior to the thyroid lobes