3. DEFINITION
An enlarged thyroid gland.
-Clinically palpable gland.
-Gland enlargement more than twice of the
normal size.
4. OVERVIEW
• Geography: Worldwide, the most common
cause of goiter is iodine deficiency.
Approximately 800million people subsist on
iodine-deficient diet.
In industrialized countries,goiter is more often
due to Hashimoto’s thyroiditis.
5. OVERVIEW
• Sex: The female-to-male ratio is 4:1.
Thyroid nodules are more likely to be
malignant in men
The frequency of goiters decreases with
advancing age. although the incidence of
thyroid nodules increases with advancing age.
• Race: No racial predilection exists.
10. BACKGROUND
• TRH:Produced by Hypothalamus. Release is
pulsatile,circadian. Downregulated only by T3.
Travels through portal venous system to
adenohypophysis. Stimulates TSH formation.
• TSH: Produced by Adenohypophysis Thyrotrophs.Up
regulated by TRH .Down regulated by T4, T3.
11. BACKGROUND
Travels through portal venous system to
cavernous sinus, then thyroid gland.
Stimulates several processes
Iodine uptake
Colloid endocytosis
Growth of thyroid gland.
• Thyroid Hormone: Majority of circulating
hormone is T4
98.5% T4
1.5% T3
12. BACKGROUND
Total Hormone load is influenced by serum
binding proteins
Albumin 15%
Thyroid Binding Globulin 70%
Transthyretin 10%
Regulation is based on the free component of
thyroid hormone
23. INVESTIGATIONS
• Imaging Studies:
Ultrasonography:Evaluate goiter
size, consistency, and nodularity. Localize
nodules for ultrasonographically guided
biopsy.
X Rays:Usually AP and Lateral with thoracic
inlet.Retrosternal goitre extension.Presence of
calcification.
24. INVESTIGATIONS
Computed tomography (CT) scanning:
Delineate the relationship of the thyroid gland
to nearby structures.CT-guided biopsies.
Radionuclide isotope scanning are used to
assess thyroid function and anatomy in
hyperthyroidism, as shown below.
26. INVESTIGATIONS
Spirometry: The flow-volume loop is useful in
determining the functional significance of
compressive goiters.
Histology:fine needle aspiration or core biopsy.
28. TREATMENT
• Observation
Small goiter
Euthyroid
Asymptomatic
• Medications:
Hypothyroidism: Thyroid hormone replacement with
levothyroxine.
Hyperthyroidism:May require medications to normalize
hormone levels for example
propylthiouacil,Methimazole
Inflamed thyroid gland, aspirin or a corticosteroid
29. TREATMENT
• Surgery: Removing all or part of the thyroid
gland-Thyroidectomy.
Large goiters with compression
Malignancy
When other forms of therapy are not practical
or ineffective
• Radioactive iodine: Treatment results in
diminished size of goiter, but eventually may
also cause a hypothyroid state.
30. TREATMENT
• Minimally-invasive modalities
Endoscopic subtotal thyroidectomy
Embolization of thyroid arteries
Plasmaphoresis
Percutaneous ethanol injection into toxic
nodule
L-Carnitine supplementation may improve
symptoms and may prevent bone loss
31. PROGNOSIS
• Complications of thyroidectomy:
• Thyrotoxic storm
• Bleeding
• Infection
• Hypoparathyroidism
• Injury to recurrent laryngeal nerve
• Injury to superior laryngeal nerve
• Hypothyroidism
32. PROGNOSIS
• A small percentage of multinodular goiters do
lead to hyperthyroidism.
• Benign goiters have a good
prognosis,furthermore,the risk of malignant
transformation is low.