5. Thyroid ENT 2014A - [Document in PDF] (2023)

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September 19, 2012

thyroid land

Dr Lago

CONTOUR

1. History and Introduction

2. Anatomy of the thyroid gland

3.

thyroid physiology

4. Diffuse thyroid disease

A. Wole

B. hypothyroidism

C.

hyperthyroidism

5. Ant assessment. neck weight

6. Thyroid cancer

HISTORY AND INTRODUCTION

The thyroid is an endocrine (threadless) gland.

First described by Thomas Wharton in 1656

submandibular gland)

Secretes a substance that lubricates the trachea

Cosmetic

The chemical is thyroxine

o Stimulates O2 consumption by most cells in the body

o Helps regulate lipid and carbohydrate metabolism

o Necessary for growth and maturation

essential for life

oNone - poor resistance to low temperatures, mental and

physical slowdown. Mental retardation/dwarfism in children

o Excessive body wasting (acceleration of metabolism resulting in

consumption of energy and body substrates), nervousness,

tachycardia, tremor, excessive heat production

THYROID ANATOMY

[2013B]

Consists of 2 lobes connected by an isthmus at level 2

eu 3

tracheal rings (tracheostomy sites)

o The thyroid isthmus covers the first rings of the trachea [boys]

o The thyroid lobes rest on the lateral wall of the trachea and may even extend upwards

hello [boys]

It is located in the anterolateral part of the trachea, just below the larynx.

The thyroid is below the cricoid cartilage

It is located under the front muscles of the neck:

the sternohyoid - most anterior

about Sternotharis

Hyoid thyroid (does not technically pass through the thyroid gland)

It is located in the muscular triangle of the neck.

oFronteiras

hyoid bone

Omohyoidalny

External cleidomastoid

[Cores]

A normal thyroid is usually not palpable.

o A palpable mass in the middle part of the neck (between

sternocleidomastoid muscles and covering the larynx and upper

windpipe) that move up and down when swallowing represent abnormalities in the functioning of the thyroid gland

oSturdy, discreet nodules are more likely to contain malignancy

o Abnormalities in the functioning of the vocal cords or the presence of palpable lymph

nodules suggest malignancy

HISTOLOGY

follicular cells

o Simple cubic epithelium surrounding a colloid-filled lumen

o

The acini are filled with a pink proteinaceous material.

(colloid)

Functions of thyroid cells:

o Collect and transport iodine

o Synthesize thyroglobulin and secrete it into colloid

o Remove thyroid hormones from thyroglobulin secretion

put them into circulation

BLOOD SUPPLY [2013B]

The superior thyroid artery (from the ACE) supplies the superior pole of the thyroid gland.

Inferior thyroid artery (from the thyrocarotid branch of the subclavian artery

Artery)

VENUS DRAINAGE [2013B]

Superior, inferior and middle thyroid veins

LYMPHATIC DRAINAGE [2013B]

Risk of metastases to:

o Central cervical nodes (levels 2, 3 and 4)

o Pre-tracheal nodules

or paratracheal nodules

NERVOUS POWER SOURCE

The superior laryngeal nerve is located close to the superior disc.

ligate the proximal thyroid to avoid nerve compression [2013B].

The injury can lead to a low voice frequency range and an inability to rise higher.

notes [Probst]

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A branch of the laryngeal nerve from the recurrent vagus nerve that passes through

trachea. Trauma can paralyze true vocal cords [2013B]

causing hoarseness [Probst]

PARATHYROID GLANDS

[2013B] It is located behind the thyroid at the upper and middle pole

Hey.

A total of 4 with 2 on each side

Fat-like yellowish color when cut

Accidental resection leads to hypocalcemiatetan

Can be implanted in other tissues like SCM

EMBRYOLOGY

First seen as an abdominal diverticulum in the fundus midline

tail to intersection 1

eu 2

branching arches in a place known as

blind hole [boys]

o Day 24: central thickening of the epithelium at the bottom appears

ectodermal pharyngeal intestine, dorsal to future tuberculum impar

[Problem]

The thyroid migrates caudally along a segment that passes ventrally to the thyroid body, then curves under it and descends to the annular level.

cartilage

final 7

week: The thyroid reaches the pre-tracheal position i

thyroglossal duct obliterated or absorbed [Probst]

THYROGLOSSOAL DUCT CYTS

Residual remnants of thyroglossal duct [Boies] due to incompleteness

obliteration or reabsorption of the thyroglossal duct [Probst]

Usually firm, tight midline swelling [Probst] found anywhere midway

the base of the tongue and the superior border of the thyroid gland, which ascends

with swallowing and moving upwards when the tongue is out [boys]

75% are present before age 5 and most are diagnosed before age 12

months [Probst]

Papillary carcinoma has been reported in thyroglossal cysts [Boies],

but malignant transformation is rare [Probst]

Treatment: o Antibiotic therapy (to treat any inflammation/infection) [Boys]

o Total excision of the cyst and thyroglossal duct with removal

middle part of the hyoid bone to prevent recurrence [Boies]

THYROID PHYSIOLOGY

THYROTROPIN-RELATED HORMONE (TRH)

Produced by the hypothalamus

Release is pulsating, circadian (21:00-12:00) [2013B]

It travels through the portal vein system to the thyrotropic system

pituitary gland cells (anterior pituitary gland)

Stimulates the production and release of thyrotropin (TSH)

Down regulation by T4

Thyroid Stimulating Hormone (TSH)

Produced by the pituitary gland

Travels through the portal vein system to the corpora cavernosa

Stimulates various processes

synthesis and release of oT3, T4

the growth of the thyroid

Regulated by TRH

Down regulation by T4, T3

THYROID HORMONES

Regulated by the hypothalamic-pituitary axis [2013B]

Most of the circulating hormone is T4

oT4 - 98.5%

oT3–1.5%

Total hormone load is influenced by serum binding proteins

o Thyroid-binding globulin (TBG) – 70%

oAlbum–15%

o Transtiretina–10%

Regulation of thyroid hormone production is based on free

component of thyroid hormone

SYNTHESIS OF THYROID HORMONES

Iodine – a raw material necessary for the synthesis of thyroid hormones

T4 and T3o Synthesized in colloid by iodination and condensation

Tyrosine molecules bound to TG

Tireoglobulina (TG)

o Synthesized in thyroid cells

o Excreted in the colloid by cell extrusion (exocytosis).

granules that also contain the enzyme thyroid peroxide

oHormones remain bound to TG until secreted

IodineIodine (active form) Iodine + TyrosineMIT and DIT T3

(MIT+DIT) and T4 (DIT+DIT) were ligated to internally armagenated thyroglobulin

light bubble [2013B]

when it is secreted

oThe colloid is taken up or taken up by the thyroid cells

Peptide bonds are hydrolyzed

o

Free T4 and T3 are released into the capillaries. Enzymes that cleave thyroxine from the TGB by lysosomes and

TGB endosomes released back into cells, and T3 and T4 in the blood

[2013B]

THE FUNCTION OF THE THYROID HORMONES

They increase the sensitivity of target tissues to catecholamines

Promote:

lipolysis

oGlikogenolyza

the gluconeogenesis

Metabolism

about HEIGHT:

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Sensitivity to catecholamines

basic metabolism

Metabolism of carbohydrates, proteins and lipids

o Normal height: increased bone turnover

normal development

o Especially the development of the central nervous system (fetal brain and skeletal system

ripening)

Regulation:

- Synaptogenesis

-

Neuronal-myelination integration

-cell migration

Endocrine system:

an increase in serum glucose

DECREASE IN SERUM CHOLESTEROL

CVS:

o Inotropic effects (increased CO)

o Chronotropic effects (increased HR)

Reproduction: Fertility requires proper thyroid function

GIT: Stimulates intestinal motility

Diffuse thyroid disease [boys]

Can be caused:

goitre

the thyroiditis

Inflammatory changes of the thyroid gland

Tenderness

Signs and symptoms of inflammation

the hyperthyroidism

the Graves' disease

advanced cancer

WOLE [2013B]

General term for enlarged thyroid gland

It's not a disease

It can be NODULAR or DISTRIBUTED

HYPERTHYROID HYPERACTIVITY

swollen skin

Weakness, decreased vitality

gaining weight

cold intolerance

Insomnia

Muscle aches and cramps

bradycardia

decreased libido

brittle nails

heavy perspiration

Irritability

WEIGHT LOSS

HEAT intolerance (incorrect

High temperature)

Muscle pain and weakness

Tachycardia

High pressure

Exophthalmos - if uncontrolled

Hypothyroidism - a decrease in the rate of oxidative energy release

reactions in body cells

Hyperthyroidism - increased metabolic rate

Most of these conditions are treated medically [2013B]

CRETINISM

Manifestation of hypothyroidism in children, which may result in

mental retardation, dwarfism, permanent immaturity and deafness [2013B]

TREATMENT

hyperthyroidism

o Partial removal or partial irradiation (destruction of the gland) decreases the level of hormone release [2013B]

o Various drugs to suppress thyroid activity (lifelong management) [boys]

FRONT NECK MASS EVALUATION

[2013B]

Most common reason for consultation: a lump in the front of the neck

Decide on conservative or surgical treatment

o Hyperthyroidism/hypothyroidism usually treated medically

o

Euthyroidism can be treated medically or surgically. ENT treatment

Endocrinologists - clinical/medical treatment

Most have clinically visible signs and symptoms, some appear normal

(subclinical variants); Subclinical - may have no symptoms

Hyperthyroidism Hypothyroidism

euthyroidism

Take a hormone test first. If hypothyroidism/hyperthyroidism is diagnosed, it should be treated

medically. In case of euthyroidism, evaluate and perform thyroid scintigraphy. If it's a hot lump,

so it's more likely to be benign, as is the dampening. If it's a cold lump then yes

high probability of malignancy, get an ultrasound of the thyroid gland and do a FNAB

required [2013B]

THYROID EVALUATION

*Hypopituitarism/hyperthyroidism = primary hypothyroidism/hyperthyroidism↑/↓ - see endo; Euthyroidism - examination (possibly malignant tumor or surgery)

TSH

Why did I ask?

o Suspected hyperthyroidism/hypothyroidism

o Presence of goiter or nodules

oMonitor response to therapy

o Screening for thyroid dysfunction in specific risk groups (formerly

thyroid surgery, DM, history of neck irradiation)

The best assessment of the integrity of the hypothalamic-pituitary-thyroid system

axis, thanks to improvements in testing

o More than 0.5 mu/ml – Hyperthyroidism

o Below 0.3 mu/ml – Hyperthyroidism

o

Normal range: 0.3-0.5 mu/ml Patients with abnormal results are referred to endocrinologists [2013B]

Otolaryngologist only treats patients with normal TSH [2013B]

FREE T3 & T4

Accurately reflects thyroid hormone production [2013B]

FT4 is most commonly used because it also reflects FT3 levels (common TBG

binding site) [2013B]

Free T4 (FT4) - measures the concentration of free thyroxine, i.e.

the only biologically active fraction in serum

Conjugated thyroxine has no effect on pituitary TSH secretion

o Free thyroxine alone has a reflex effect on TSH

secretion

TSH

INCREASED

Soro FT4

Increased

Hypothyroidism Pituitary Gland

Reduced

hypothyroidism

REDUCED

Soro FT4

Increased

hyperthyroidism

Reduced

hyperthyroidism

NORMAL

euthyroidism

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Free T4 is unaffected by changes in binding concentration

proteins, i.e. conditions such as pregnancy, estrogen or androgen

therapy does not affect FT4 levels

Razem T3/T4

T3 measures the concentration of triiodothyronine in serum

T4 measures the concentration of thyroxine

The test measures connected and unconnected shapes

Limited, therefore, without direct correlation with the metabolic state

May be affected by changes in thyroid binding level

globulins, albumin levels. Conditions such as use of contraceptives

pills, acute liver disease will increase protein binding

RADIOACTIVE IODINE INTERCEPTION (RAIU)

Measurement of iodine uptake by the thyroid gland

extracellular pool for a certain period of time

Useful in indicating hyperthyroid conditions

TYROGLOBULINA

10% of normal people

15-30% of patients with AC

Unbelievable [2013B]; Best for follow-up after CA after thyroidectomy

Label residual thyroid cells after thyroidectomy [2013B]

Thyroid scintigraphy/thyroid scintigraphy

Thyroid radionuclide imaging

One of the first procedures developed in nuclear medicine

It is not preferred for neck tumor debridement as the examination is very time consuming.

preparation (radioactive tracer) and is only available in some cases

institutions

Absorption studies involve measuring the amount of tracers

secreted by the thyroid gland at a given time

o Concentrated on the thyroid, which allows visualization

gland

Iodine isotopes are the most commonly used radiotracers

(I-123, I-131) e nadtechnecjan technetu (Tc99-m)

o Of the three, technetium pertechnetate can be used

children due to short imaging time and less radiation exposure

oRadioactive iodine is administered orally and reaches the body

the follicle lumen in 20-30 minutes

I-131 has a half-life of 8 days compared to I-123, which does not

half life 13 hours

-Increased emission of particulate matter in the gland

-Stays in the body for a long time

An alternative is Tc99-m with a half-life of only 6 hours

-Low particle emission -Short imaging time and reduced exposure to radiation [2013B]

-Good for kids

It is read as hot (increased uptake) or cold (decreased uptake) nodules.

depending on thyroid tracer uptake [2013B]

Suspected thyroid nodule

thyroid scan

"HOT" "COLD" Multitubes

nodules nodules

Ultrasound with hormone suppression Clinical signs

gentle malice

Biopsy

About. 80-85% are "cold" and 14-22% of malignancies require surgical treatment [2013B]

5% are "hot" at 2 cm, there is a high probability that they will not change in sizeo If unsuccessful or signs of malignancy appear, surgery is required

[Cores]

10-15% are hot

The scan is 89-93% sensitive but only 5% specific.

Indications:

1.

Identification of functional solitary nodules when baseline serum thyrotropin is reduced

2. If FNAB results indicate a "follicular" or "suspicious" tumor

results, finding a "hot" nodule may reduce the risk

malice

3.

Detection of metastases in the neck

ULTRASOUND

Ultrasound - sound is reflected back

The test is easily available, which is why it is often used to develop cervical mass.

Can detect small nodules (

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o Non-diagnostic fine needle aspiration (as an addition to repeat

BANCO)

UTZ

cystic solid

FNAB

Malicious Mild Suspect

FINE NEEDLE ASPIRATION BIOPSY (FNAB)

The most useful test to determine your solitary nature

nodule (benign or malignant? what type of cancer?)

o A 20-25 gauge needle with a local anesthetic (MASir

personally uses a 23 gauge needle without local anesthesia) 10 cc from a 23 gauge needle - the mass is punctured and aspirated at approximately 4-

pressure 5mm [2013B]

o4-5 separate skin punctures for the nodule to obtain

a suitable specimen

oMust have an experienced cytopathologist

o Extremely safe and inexpensive

oLarge core needle biopsy (size 18,19,21)[2013B]

Increased complication, size limitation and additional information compared to FNAB

Not Used by Doctor: He says they tend to use large diameter needles

aspirate blood (blood tap)

Accuracy rates range from 50 to 90% with a low false positive rate (90%

4 CATEGORIES RECOGNIZED FOR FNAB

1.

Mean

2.

Light

3. Suspicion

4.

Insufficient

RESULTS GUARANTEE A SUSPENSION LABEL

1.

Hurtle cell neoplasm

2.

Follicular variant of papillary carcinoma

3. Low-grade papillary carcinoma

4. Choroba Hashimoto

FNAB RESULTS MANAGEMENT ALGORITHM

LIGHT

It is unpredictable and therefore requires careful observation

o Repeat FNAB after 6-24 months

oBenefits of thyroid suppression in five separate studies reported in

doses in the range of 100-200 μg were considered insignificant

shrunken nodules, especially those > 2 cm in size [2013B]

MEAN

o It is simpler with a predictive value for a positive value

PAAF is close to 100% and specificity is 100%

the guaranteed functioning

SUSPECT

o Includes follicular carcinoma and Hurthle cells

the limiting factor BACC

oThe rate of malignancy is only 10-20%

oSurgical management is indicated. oLook for poor clinical indicators if poor indicators are present

is more likely to be malicious [2013B] and guarantees ifmalignantAge(60) operation

male)

previous radiation

family history

Dor

Compressive or invasive features

Metastases to the cervix

Size (>4cm)

Rapid growth

INSUFFICIENT

o Requires USG-guided FNAB replay

THYROID SUPPRESSION

1.

Administer levothyroxine 2. Maintain TSH levels at a level

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Orphan Annie's Sign: Prominent testicles

Peak incidence - 3rd decade of life

Female to male ratio 3:1

Propensity to spread to lymph nodes in 30-50% of patients

o Lymph node metastasis has no impact on survival

o Presence of lymph nodes may indicate papillary carcinoma

Late metastases in the lungs and bones

Multicentric seen in 30-60% of patients (higher incidence seen in

irradiated patients) – don't just remove one lobe, remove another lobe [2013B]

favorable prognosis

5-year survival rate: 90-95%

Occult, incidental CA of the thyroid gland (50 years)

Death from verrucous CA depends on:

Age > 50 years

oSize and grade of the tumor

o The initial extent of the disease

NECK SIDE METAL PATTERNS IN APPROX.

Level 1 14%

Level II 52%

Level III 57%

4th level 41%

Poziom V 21%

Most metastases are found in the deep cervical lymph nodes

Levels II-V are most often involved, so selectively

dissection (SND) II, III, IV and V is the treatment of choice

Location of positive nodes Number of cases

medium neck 85

Lower neck 67

top neck 50

Posterior neck 22

superior mediastinum 7

Submandibular 4

CD Haagensen on. 1972

FILLER CANCER

They occur in older patients, usually aged between 40 and 60 years.

The ratio of women to men is probably about equal

Tendency to angioinvasion and hematogenous spread

Metastases to lymph nodes are not a feature and occur only

po angioinwazji

Distant metastases to lungs and bones seen in 50-65% of patients,

and are detected and treated with radioactive iodine I-131 as follows

total thyroidectomy

Category:

A. Low quality: encapsulated, well differentiated

B. High Grade: Angioinvasive and Hurthle Cell CA

10-year survival rate 30-85%, depending on tumor stage and

BUT NOT by tumor size (Average = 70%)

Distinguish follicular adenoma based on capsular, vascular or

stromal invasion. Differentiation is difficult through the frozen section and

impossible by FNAB

These tumors concentrate I-131 very well, but may lose this resource in older patients, resulting in a worse prognosis.

TREATMENT OF DIFFERENTIAL THYROID CANCER

Controversy concerns the extent of required thyroid resection and

degree of lymph node dissection

o Papillary CA – total thyroidectomy + LN resection

o Follicular CA – total thyroidectomy

Some data suggest similar survival with total thyroidectomy.

Ipsilateral thyroid lobectomy and cismectomy

Treat all patients with exogenous papillary or follicular AC

thyroid hormone or TSH suppression throughout life. TSH serum concentration

should be nearly undetectable, but toxicity should be avoided

TOTAL THYROIDECTOMY

Treatment of multicentric disease (30-80%)

Probably lower recurrence rate Postoperative use of I-131 iodine and thyroglobulin

Low incidence of recurrent nerve paresis/hypoparathyroidism

THYROID LOBECTOMY

Avoid hypoparathyroidism and bilateral recurrent nerve damage

Based on similar survival data

Difficult, if not impossible, to use I-131 after surgery

treat local and/or distant metastases after I-iodine ablation

131

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RADIOACTIVE IODINE THERAPY

It relies on the affinity of thyroid tissue to address iodine uptake

residual or metastatic disease

It can give a big dose of I-131 iodine and save the environment.

thyroid tissue before injury

The PRIMARY application is in patients after total thyroidectomy

Indicated in ALL patients with LN or distant metastases

Can be used selectively in patients with limited thyroid CA

thyroid gland after total removal of the thyroid gland

Withhold all exogenous thyroid hormones for 3-4 weeks and

confirmation of preparation by elevated serum TSH

EXTERNAL RADIATION

Appears to be useful only in selected locally invasive thyroid CAs (usually

aggressive follicular tumors) and anaplastic AC

CHEMOTHERAPY

There is currently no use

THYROID CANCER (RTC)

Originally described by Hazard and colleagues in 1959

Solid histological pattern with stromal amyloid and calcification

view

In 1967, MTC discovered a link with calcitonin secretion

Perifolicular C cells of neural crest origin (ultimobranchial body) in

thyroid

Elevated serum calcitonin levels are usually present in CMTs and

form a reliable marker for the presence of occult origin of MTC

cases and recurrent CMT in previously treated patients

Metastases to the LN detected in 50% of patients have an adverse effect

for survival and are treated with a modified radical neck resection. Systemic metastases do not respond to radiation and CMT does not

Iodine Concentrate I-131. Usefulness of chemotherapy

(adriamycin and cisplatin) is limited

Diarrhea, increased intestinal motility, and elevated calcitonin may occur.

be the first symptom of recurrent CMT

ANAPLASTIC CANCER

Unusual thyroid cancer in elderly patients

May result from well-differentiated thyroid CA

80% of patients have a history of sudden-onset prolonged goiter

rapid growth, hoarseness, dysphagia, and respiratory failure

Tracheal invasion and/or recurrent bilateral nerve palsy may occur.

to be seen

Poor prognosis, usually results in 100% death when diagnosed, z

life expectancy 6-9 months

Death occurs as a result of local invasion of vital structures of the cervix and

airway compression

Surgical excision is rarely possible without sacrificing an essential element

structures of the cervix, but tissue diagnosis is necessary to differentiate

it's lymphoma. They usually don't work anymore

Both tracheostomy and total thyroidectomy are extremely difficult

External radiation can temporarily control local effects

malice

Limited effect of systemic chemotherapy (adriamycin);

No known hormonal manipulations

Bibliography:

2013B Trans, Recording, Lecture, Probst, Boies