Functionality and Thyroid Hormone Imbalance
The role of the thyroid gland is to produce, store and circulate thyroid hormones in the entire body.
Thyroid hormones regulate breathing, heart rate, blood pressure, metabolism, menstrual cycles and mood. As such, an imbalance in thyroid hormone levels can negatively affect our vital body functions and mood. Thyroid hormone levels can be checked using blood tests. Blood tests can tell if the thyroid is hyperactive (hyperthyroidism) or underactive (hypothyroidism). Overt hyperthyroidism may be treated with antithyroid medication, radioactive iodine or surgery whereas overt hypothyroidism is usually treated with thyroid hormone medications.
On the more serious end of the spectrum, recent reports have shown that there is an increase in the number of cases of thyroid cancer globally in the past 3 decades. This is due to multiple risk factors, 1 of which is radiation exposure. Radiation exposure can be from medical treatment, radiation fallout from nuclear reactor accidents and from nuclear weapons. For unclear reasons, thyroid cancer occurs about 3 times more often in women than in men and can occur at any age but peaks in the 40s or 50s. Interestingly, there is also risk of thyroid cancer in people who are overweight or obese. Swelling, lumps or enlarged lymph nodes found in the neck are common symptoms of thyroid cancer.
Thyroid cancer manifests first as a thyroid nodule before enlarging into a mass if not treated. A nodule is growth of abnormal tissue which can be felt as a lump. Most thyroid nodules however, are non-cancerous with approximately 5% being cancerous. The commonest type of cancer is papillary thyroid cancer followed by follicular thyroid cancer being the 2nd most common.
Ultrasound in Thyroid Imaging
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