1/58
Looks like no tags are added yet.
Name | Mastery | Learn | Test | Matching | Spaced |
---|
No study sessions yet.
What is the size of the thyroid?
4-6 cm
2-3 cm in depth and width
What is the size of the isthmus?
2-6mm
The structure connecting the right and left lobes of the thyroid is?
The isthmus
Euthyroid function means the thyroid function is?
Normal
What are the muscles anterior to the thyroid?
Strap muscles
-Sternohyoid
-Sternothyroid
-Omohyoid
Which muscle is located posterior to the thyroid?
Longus colli muscle
What is the function of the thyroid?
Produces, Stores and Secretes hormones
Regulates body growth
Body development
Controls metabolism
Increased levels of TSH indicate what?
Hypothyroidism
Decreaded levels of TSH indicate what?
Hyperthyroidism
Another name for TSH is?
Thyrotropin
Increased T3 and T4 indicate
Decreased T3 and T4 indicate
Hyperthyroidism
Hypothyroidism
What are some symptoms of hypothyroidism
Weight gain
Hair loss
Lethargy
Enlarged goiter
Cold
T/F Hashimoto's is a form of Hyperthyroidism
False, Hypothyroidism
Symptoms of Hyperthyroidism
Weight loss
Increased Appetite
Nervousness
Sweating
Enlarged goiter
T/F Hot nodules on NM exam are worrisome for thyroid cancer
False Cold nodules 20% malignant don't take up iodine
Hot nodules are non-malignant
What are some reasons for performing a thyroid ultrasound
Abnormal TFT's
Palpable nodule
Enlarged thyroid
Difficulty swallowing/ breathing
Evaluation of a cold nodule on NM exam
Follow-up
Assist in biopsy/ FNA of nodule
Describe the proper patient position for performing a thyroid ultrasound
Supine
Pillow under shoulders
Hyperextend neck
What are some questions you would ask your patient before performing an ultrasound?
Palpable mass
Thyroid medications
Abnormal labs
Previous imaging
Family hx of thyroid CA
Hx of radiation or prior thyroid surgeries
Thyroid protocal
Bilateral TRV w and w/o color
Isthmus
Rt/Lt Lobe Sag w and w/o color
Rt/Lt Lobe Sag Med
Rt/Lt Lobe Sag Lat
Rt/Lt Lobe Trv Sup
Rt/Lt Lobe Trv Mid w and w/o color
Rt/Lt Lobe Trv Inf
Scan Lat to great vessels for abnormal lymph nodes
Document and measure any masses
Why would you scan lateral to the jugular veins when performing a thyroid ultrasound?
To look for enlarged or abnormal lymph nodes
Normal thyroid sonographic appearance
Homogenous texture
Medium level echogenicity
Echogenic Capsule
Normal lymph node appearance
Hypoechoic
Oval
Echogenic Hilum
Vascular hilum
< 0.5
Overall worldwide, the most common cause of thyroid disorders is?
iodine deficiency
Most common cause of thyroid disorders in developed countries is?
autoimmune processes
What is the definition of a thyroid goiter?
Enlargement of the thyroid gland
Causes of a goiter?
Compensatory hypertrophy and hyperplasia
Graves' Disease
Throiditis
Neoplasm
Cyst
Nontoxic goiter
Diffuse Thyroid enlargement
Can be result of iodine deficiency
Normal or hypothyroid secretion
Within the control of pituitary gland
Toxic goiter
Most common forms of thyroid disease
Results in an enlarged nodular gland
Hypersecretory
Often caused by excessive stimulation from TSH
Graves disease
Women
>30 years old
Autoimmune disorder
Thyrotoxicosis
Most common cause of Hyperthyroidism
"thyroid inferno"
What is the classic clinical finding seen in patients with graves disease?
Exophthalmos
Thyroiditis can be caused by?
Caused by infection
Can be autoimmune
Causes swelling and tenderness
Destroys thyroid gland
What are the two types of thyroiditis
De Quervain's Thyroiditis
Hashimotos
What is De Quervain's
Viral infection
Diffuse enlargement and inflammation
Eventually gland returns to normal
Hashimoto's Disease
Autoimmune disorder
Causes chronic inflammation
Usually occurs in young-mid aged women
Thyroid is diffusely enlarged
Hypothyroidism
Increased rate of malignancy
Describe the typical sonographic appearance of Hashimoto's disease
Heterogenous
Hypervascular
Coarse texture
Fibrotic septations
Enlarged
How can you tell the difference between a thyroid affected by graves disease vs. hashimoto's disease?
Through labs
Sonographically there is no differance
What are two benign thyroid lesions
Thyroid cysts
Adenoma
Adenoma
Benign
Females 7x more than Males
Euthyroid-normal
Hyperthyroid
Can be multiple
Sonographic findings of an adenoma
Variable
From anechoic to Hyperechoic
Fibrous capsule
Well circumscribed
May have a hypoechoic halo
May have a calcified rim
Can have hemorrhage
Necrosis
What are some risk factors for malignant thyroid lesions
Age 25-65
Female
Asian
Family history
History of radiation to head or neck
What are the types of malignant thyroid lesions
Papillary Carcinoma
Follicular Carcinoma
Medullary Carcinoma
Anaplastic Carcinoma
Lymphoma
Papillary Carcinoma 5
1.Most common
2.Least aggressive
3.Good prognosis
4.25% Mets to cervical lymph
5.Small punctate calcifications
Follicular Carcinoma 4
1. Single mass
2. 2nd most common
3. Spreads through blood
4. Mets to 4 thing
-Brain
-Lung
-Bone
-Liver
Medullary Carcinoma 3
1. 10%
2. Nodule or whole gland
3. Microcals
Anaplastic Carcinoma
Rare
Rapid growth
Highly metastatic
Elderly patients
Invade through surrounding muscles
Lymphoma
Non-Hodgkin's type
Primarily affects older women
Rapidly Growing
Chronic Hashimoto's
Abnormal Cervical lymph nodes
Rounded
Hypoechoic
Absence of fatty hilum
Punctate Calcs
Cystic changes
>0.5
Cysts of the neck
Brachial cleft cysts
-Congenital
-Lat neck mass
-Beneath mandible
Cystic Hygroma
-inadequate drainage of lymph fluid
-Post neck mass
Thyroglossal Cyst
-Embryonic remnant
-Anterior
-between tongue and isthmus
What are some Pitfalls Of Thyroid Imaging
Edge refraction shadowing from muscles anterior
Clavicle
Swallowing/ Breathing/Talking
Taut neck muscles
Parathyroid glands
4 total
< 4mm
> 5mm is considered abnormal
What is the function of the parathyroid
Regulates blood calcium levels
-bone
-intestines
-kidneys
Decreased calcium levels causes Parathyroid gland to produce and secrete what?
more PTH
- Causes glands to enlarge
- Pregnancy can also cause glands to enlarge due to an increased need for Calcium
Increased calcium levels causes Parathyroid glands to?
stop producing PTH
Primary hyperparathyroidism
Increased function
Woman are affected 2-3x more than men
Common after menopause
Leads to Hypercalcemia and Hypercalciuria
Asymptomatic
The most likely cause of hyperparathyroidism is?
Adenoma
Parathyroid Adenoma
Benign
< 3cm
1 gland
Hypoechoic
Symptoms: "Stones, Bone, Groans and psychic overtones"
Secondary Hyperparathyroidism
Hypocalcemia
Caused by
-Renal failure
-vitamin D deficiency
-malabsoption
Causes stimulate parathyroid to excrete excessive PTH
Affects all 4 glands
Hypoparathyroidism
Undersecretion of PTH
Rare
Can be
-Congenital
-Genetic
-Autoimmune
-Caused by removal of parathyroid glands
Treated with Vitamin D and Calcium
Parathyroid cancer
Very Rare
Small
Difficult to diagnose early