An image taken of a patient’s thyroid gland after the patient swallows radioactive iodine or technetium. The image shows the thyroid gland in action as it accumulates radioactive material. Thyroid scanning is used to determine how active thyroid tissue is in manufacturing thyroid hormone. This can help a physician determine whether inflammation of the thyroid gland (thyroiditis) is present. It can also show the presence and degree of overactivity of the gland (hyperthyroidism). Thyroid scanning is especially helpful in evaluating thyroid nodules, particularly after a fine-needle aspiration biopsy has failed to provide a diagnosis. A scan can reveal whether a thyroid nodule is functioning. A functioning nodule actively takes up iodine to produce thyroid hormone, and so it produces a localized ‘hot’ area on the image. A nonfunctioning nodule does not take up iodine, and it produces a localized ‘cold’ area. Most nodules, particularly if they are functioning, are not malignant.
- Thyroid stimulating hormone
A hormone produced by the pituitary gland at the base of the brain in response to signals from the hypothalamus gland in the brain. Thyroid stimulating hormone (TSH) promotes the growth of the thyroid gland in the neck and stimulates it to produce more thyroid hormones. When there is an excessive amount of thyroid hormones, […]
- Thyroid stimulating immunoglobulin (TSI)
A form of immunoglobulin G (IgG) that can bind to thyrotropin (TSH) receptors on the thyroid gland. TSIs mimic the action of TSH, causing excess secretion of thyroxine and triiodothyronine. The TSI level is abnormally high in persons with hyperthyroidism due to Graves’ disease.
- Thyroid storm
Thyroid storm is a severe, life-threatening condition caused by an excess of thyroid hormone. A number of factors can be involved in causing thyroid storm, including over-replacement of thyroid hormones or discontinuing medications taken to treat hyperthyroidism. Symptoms of thyroid storm can include fever (potentially as high as 105-106 degrees F), racing pulse, nausea,vomiting, diarrhea, […]
Surgery to remove part or all of the thyroid gland. Thyroidectomy might be done to remove a tumor or to treat hyperthyroidism or goiter (enlarged thyroid gland). Complications of the surgery can include vocal cord paralysis and accidental removal of the parathyroid glands, which are located behind the thyroid gland. Because the parathyroid glands regulate […]
The inflamed thyroid gland can release an excess of thyroid hormones into the blood stream, resulting in a temporary hyperthyroid state. Once the thyroid gland is depleted of thyroid hormones, the patient commonly goes through a hypothyroid (low thyroid) phase. This phase can last 3-6 months until the thyroid gland fully recovers. Thyroiditis can be […]