Superficial structures exam 3(thyroid, scrotum and msk)

Thyroids gland is an organ of what system?

endocrine

thyroid does what?

maintains body metabolism, growth and development

thyroid is regulated by what?

pituitary and hypothalamus gland

thyroid location

anterior lower neck (anteroinferior) on either side of the midline

thyroid is bounded laterally by?

carotid arteries and jugular veins

anatomic variant representing a superior sliver of thyroid tissue arising from the isthmus

Pyramidal lobe

Adult thyroid measurements

length: 40-60mm

AP: 20-30mm

width:15-20mm

isthmus: 4-6 mm AP

newborn thyroid measurements

length: 25mm

AP: 12-15mm

width: 10-15mm

Powerpoint says

length: 18-20

AP:8

width: 9

thyroid is considered enlarged when it measures

AP: greater than 20mm

isthmus: 10mm or greater

anterior to the thyroid

strap muscles (sternohyoid, sternothyroid and omohyoid) and the anterolateral sternocleidomastoid

lateral to the thyroid

common carotid, internal jugular vein, and the vagus nerve

posterior to the thyroid

the longus colli muscle lies posterior and lateral to the thyroid and along the anterior surface of the cervical vertebrae

along the posterior border are the parathyroid glands, along with the anastomosis between the superior and inferior thyroid arteries

medial to the thyroid

larynx, trachea and the inferior constrictor muscle of the pharynx

esophasgus seen to the left of the midline, lateral to the trachea (appears as a target )

vascular supply for the upper poles of the thyroid

two superior thyroid arteries arise from external carotids and descend to upper poles

vascular supply for the lower poles of the thyroid

two inferior thyroid arteries arise from thyrocervical trunk of subclavian artery and ascend to lower poles

thyroids veins drain into what?

internal jugular veins

the thyroid is made up of two types of cells:

follicular- majority of thyroid tissue and secrete the main hormones T3 and T4 (require iodine to produce correct amounts)

parafollicular- also called C cells- secrete calcitonin

thyroid stimulating hormone (TSH) produced by?

pituitary gland

TSH is regulated by what?

thyrotropin release hormone (TRH)

TRH produced by?

hypothalamus

calcitonin does what?

decreases the concentration of calcium in the blood

clinical sign and symptoms of Hypothyroidism

weight gain, hair loss, increased subcutaneous tissue around eyes, lethargy, intellectual and motor slowing, cold intolerance and a deep husky voice

Hyperthyroidism clinic signs

weight loss, increased appetite, high degree of nervous energy, tremor, excessive sweating, heat intolerance, palpitations and exopthalmos

extreme form of hyperthyroidism

thyrotoxicosis

nuclear lab tests for thyroid

iodine uptake scan

thyroid scan

absence of uptake indicates?

cold nodules: can indicate malignancy

T4 & T3

thyroxine(T4) and Triiodothronine (T3)- aids in the metabolism of fats, proteins and carbs

calcitonin is usually a test for?

medullary carincoma-mainly used as a tumor marker, not necessarily used for thyroid function

what frequency transducer should be used to examine the thyroid?

high freq (7.5-15MHz)

other terms used to describe goiter

nodular hyperplasia, multinodular goiter and adenomatous hyperplasia

what is the most common thyroid abnormality

goiter

goiter caused by?

iodine deficiency and sometimes by thyroditis

hyperthyroid condition resulting from nodular enlargement that causes hyperactivity of the thyroid gland

toxic goiter

diffuse thyroid enlargement not resulting from neoplasm or inflammation

non toxic (simple) goiter

sonographic findings of goiter

gland becomes hyperechoic as gland enlarges (powerpoint says)

“nodules can vary in echogenicity due to fibroisis, colloid, focal scarring, ischemia, cystic degeneration, or calcification.

nodules may present as poorly circumscribed or well defined and encapsulated by a thin peripheral hypoechoic halo

increased vascularity

clinical findings of goiter

dysphagia, neck veins, pressure on the trachea, hoarseness

cyst with echogenic foci

colloid cyst

cyst that demonstrates a comet tail artifact

colloid cyst

cyst that demonstrates low level echoes with possible fluid and debris level with possible wall irregularities and internal septations

hemorrhage cyst

what are colloid cysts filled with?

a stored hormone from the thyroid called colloid

adenomas more common in male or female?

female

7 times more common

adenomas represent what percentage of all nodular diseases of the thyroid

adenomas (follicular adenoma)

ademonas are usually… (growth patterns)

solitary and slow growing, unless hemorrhage occurs which can cause sudden pain and enlargement

adenomas appear how

compression of adjacent tissue and fibrous encapsulation

sonographic findings of adenomas

anechoic to completely hyperecchoic, commonly with a peripheral hypoechoic halo, homogenous

can exhibit increased blood flow on doppler with peripheral borders or within lesion

calcification along the rim with an “eggshell” appearance with shadowing can also be seen

hot nodules are?

hyper functioning thyroid nodules seen on a nuclear study that are almost always benign

what would suggest malignancy?

a solitary markedly hypoechoic thyroid nodule with the presence of cervical lymphadenopathy (cervical adenopathy) on the same side

most common of thyroid malignancies

papillary carcinoma (approx. 70% of thyroid cancers)

sonographic findings of papillary carcinoma

hypoechoic, microcalcifications, hypervascularity

papillary carcinoma cervical lymph node metastasis seen in approx. what percentage of cases?

20-50%

follicular carcinoma two types

minimally and widely invasive

very agressive

minimally invasion follicular carcinoma sonographic appearance

well encapsulated. demonstration of focal invasion of capsular blood vessels of the fibrous capsule

follicular carcinoma spreads how?

through the bloodstream (rather than the lymphatic system)- metastatis to the bone, lung, brain and liver.

sonographic findings of follicular carcinoma

thick irregular halo and tortuous internal blood vessels with increasee vascularity

medullary carcinoma accounts for what percentage of thyroid cancers?

5%

medullary carcinoma derives from?

from the parafollicular or C cells of the thyroid that secrete calcitonin

sonographic appearance of medullary carcinoma

similar to papillary; solid mass marked by hypoechogenicity and calcifications. hard bulky mass

powerpoint says “punctuated, bright foci within solid mass and lymphadenopathy”

medullary carcinoma tends to spread where?

the liver

anaplastic carcinoma accounts for less than what percentage of cancers?

less than 2%

anaplastic carcinoma usually occurs in whom?

twice as common in men than women after the age of 60-may be seen many years after radiation exposure to neck or upper chest

sonograhic findings of anaplastic carcinoma

hypoechoic mass, invasion of surrounding muscles and vessels of neck and widespread metastasis

thyroiditis caused by

infection or autoimmune disease

chronic lymphocytis thyroiditis is known as?

hashimotos disease

most common thyroid disorder in america and also the most common cause of hypothyroidism

hashimotos

Hashimotos caused by?

destructive autoimmune disorder which leads to chronic inflammation

hashimotos most commonly seen in?

young or middle aged women

hashimotos clinical findings

pallor, under eye puffiness, dry skin, depression, peripheral edema

sonographic findings of hashimotos

coarse, heterogenous, multiple ill defined hypoechoic areas seperated by fibrous strands. doppler shows normal to decreased flow velocity., occasional “thyroid inferno” pattern seen when hypothyroidism develops

most common cause of hyperthyroidism?

Graves disease

graves disease most commonly seen in?

women greater than 30 years old

thyroid appearance with graves disease

diffusely homogenous and enlarged

symptoms of graves disease

hypermetabolism, toxi goiter, heat intolerance, nervousnes, weight and hair loss, tachycardia and oligomenorrhea

sonographic findings of graves disease

hypoechoic, heterogenous with diffuse enlargement, hypervasculaity; thyroid inferno

parathyroid glands located where?

on posterior medial surface of thyroid gland- two lie posterior to each superior pole and two lie posterior to inferior pole

what does PTH do? (parathyroid hormone)

increases calcium level when needed

high calcium may cause what?

renal stones, ulcers and bone pain

size of parathyroid glands

5 X 3 X1 mm

parathyroid glands often confused for what?

longus colli muscle

primary hyperparathyroidism most common in?

females after 40

symptoms of hyperparathyroidism

nephrolithiasis, abdominal or MSK pain or osteopenia

primary hyperplasia occurs in what kind of patient?

10% occur with hyperparathyroidism

one gland may be significantly enlarged, or all glands may be enlarged

most common cause of hyperparathyroidism

ademona- 80-85% cause

parathyroid adenoma clinical findings

elevated serum calcium and PTH

parathyroid carcinoma appear?

small, irregular and firm and adhere or invade surrounding structures

SONOGRAPHIC APPEARANCE OF PARATHYROID CARCINOMA

lobular contour

thyroglossal duct cysts are located where

midline neck anterior to trachea

thyroglossal duct cysts are caused by?

congenital-atrophy failure of thyroid remnant between tongue and hyoid bone

branchial cleft cyst located where?

lateral portion of the neck- lateral to the submandibular region

brancial cleft cyst caused by

diverticulum of the brancial cleft extending from the paryngeal cavity to the auricle opening- fills with fluid causing a cyst

abscess appears how?

fluid filled to completely echogenic

commonly seen as low level echogenic with irregular walls

clinical presentation of abscess

pain ,erythema, edema, fever and a palpable mass

can abscesses be aspirated?

yes

normal appearance of a lymph node

oval, symmetric, homogenous, thin outer cortex and an echogenic central hilum. should not exceed 1 cm. doppler should show blood entering the hilum

sonographic appearance of lymphdenopathy

more rounded shape/lobulated shape and loss of echogenic hilum.

may present with calcifications and a more complex cystic appearance from necrosis

color may show increased vascularity or avascularity

go study the lymph nodes levels of the neck

each sac of the the scrotum consists of two layers:

skin and tunica vaginalis

a covering of the testes which is a double layer extension of peritoneum

tunica vaginalis

two layers of the tunica vaginalis

parietal (outer) -inner lining of the scrotal wall

visceral layer (inner)- surrounds the testes and epididymis

where do hydroceles form?

in the space between the layers of tunica vaginalis

measurements of the testes

length: 3-5 cm

width: 2-4 cm

height: 3 cm