Lesson 1E (Part 2) Flashcards
Toxic nodular goitre
One or two nodules of a gland that is already affected by goitre become active and secrete excess T3and T4
What does toxic nodular goitre cause?
Effects of hyperthyroidism
Who is toxic nodular goitre more common in?
Women
- after middle age (older than graves disease)
What is more common in the older age group than toxic nodular goitre? (2)
- Arrhythmias
2. Cardiac failure
What is another name for autoimmune thyroiditis?
Hashimotos disease
What is the most common cause of acquired hypothyroidism?
Hashimotos disease
Who is hashimotos disease more common in?
Women
Autoimmune thyroiditis
Organ-specific autoimmune condition
- goiter sometimes present
What are the characteristic sonographic patterns of hashimotos thyroiditis? (4)
- Diffusely coarse echotexture
- Innumerable tiny hypoechoic nodules that may become confluent
- Interspersed with echogenic fibrous bands
- Vascularity
- increase, decreased or normal
Confluent
Run together
What are 2 other names for an adenoma?
- Colloid
2. Adenomatous nodule
Adenoma
Hyperplastic nodule
What is the most common lesion in the thyroid?
Adenoma
What is the sonographic appearance of an adenoma?
- Isoechoic
- but can also be hypoechoic - Commonly undergo cystic and hemorrhagic degeneration
- Larger solid masses may be entirely echogenic
- Degeneration of hyperplastic nodules
- dystrophic calcification = either coarse internal calcification or peripheral ‘‘eggshell’’ calcification
Goiter
Enlargement of the thyroid gland without signs of hyperthyroidism
What is goiter caused by?
A relative lack of T3and T4
What do low levels of T3 and T4 stimulate?
Secretion of TSH resulting
What does stimulating of TSH result in?
Hyperplasia of the thyroid gland
Hyperplasia
The enlargement of an organ or tissue caused my an increase in the reproduction rate of its cell
What develops when you have hyperplasia of the thyroid gland?
Hypothyroidism
What are causes of goiter? (3)
- Persistent iodine deficiency
- dietary iodine deficiency (endemic goitre) - Genetic abnormality affecting synthesis of T3and T4
- Iatrogenic
- e.g. antithyroid drugs, surgical removal of excess thyroid tissue
What can enlarged glands cause from goiter?
Pressure damage to adjacent tissues
What structures are most commonly effected from goiter? (3)
- Oesophagus
- dysphagia (hard to swallow) - Trachea
- dyspnoea (hard to breath) - Recurrent laryngeal nerve
- hoarseness of voice
What kind of nodules do you get from goiter?
Multinodular
- very common
- multiple hyperplastic nodules with varying degrees of colloid, necrosis, or hemorrhage
- multiple masses of varying size and echo texture***
What kind of echotexture does goiter have?
Heterogeneous
How common are malignant tumours of the thyroid gland?
They are rare
What is the only well established risk factor for differentiated thyroid cancer ?
External head and neck radiation
- especially during infancy
What is the most common thyroid malignant tumour?
Papillary cancer
- 75-80% of thyroid cancers
What are sonographic findings of papillary cancer? (4)
- Punctuate, non-shadowing echogenic foci
- microcalcifications - Solid **
- Hypoechoic **
- Intrinsic vascularity **
