Goiter refers to enlargement of the thyroid gland. It can occur from multiple conditions.
The definition of a goiter depends on age and sex; below are the upper limits of normal for thyroid gland volume 1:
- adult males: 25 mL
- adult females: 18 mL
- 13-14 years: 8-10 mL
- 3-4 years: 3 mL
- neonate: 0.8-1.5 mL
The prevalence of goiter varies widely depending on the level of iodine deficiency. In severely iodine-deficient areas the prevalence may be as a high as 80%. Goiter is more common in women (M:F = 1:4) and incidence declines with age 5.
The thyroid gland may become so enlarged that it becomes a substernal goiter.
The cause of goiter is diverse 2,3:
- non-toxic simple goiter (e.g. from iodine deficiency)
- Graves' disease
- multinodular goiter
- Hashimoto thyroiditis
- thyroid cancer
- drugs: lithium, amiodarone, etc
- diet: cabbage, sprouts, etc
- depositional disease, e.g. amyloidosis
Thyroid volume can be estimated by measuring each lobe and applying the following correction factor for an ellipsoid formula 6:
- height (cm) x width (cm) x depth (cm) x 0.529*
* various correction factors have between 0.494-0.554 have also been proposed 6
History and etymology
Goiter derives from the old French "goitron" meaning gullet. Goitron comes from the Latin "guttur" meaning throat.
See main article: midline neck mass