Overview

The thyroid gland produces hormones that regulate metabolic rate while parathyroid glands control calcium homeostasis via parathyroid hormone. Thyroid follicles synthesize thyroxine and triiodothyronine and parathyroids respond to serum calcium levels. Gland dysfunction affects multiple organ systems.

Thyroid Structure and Function

Thyroid follicles concentrate iodine and produce thyroid hormones that influence metabolism growth and thermogenesis. Nodules goiters and autoimmune thyroiditis alter function and structure. Ultrasound and nuclear imaging evaluate nodules and function.

Parathyroid Physiology

Parathyroid glands secrete PTH to increase serum calcium by acting on bone kidney and intestine. Hyperparathyroidism causes hypercalcemia and bone loss while hypoparathyroidism leads to hypocalcemia. Localization imaging guides surgical removal of adenomas.

Clinical Relevance

Thyroid and parathyroid disorders include hypothyroidism hyperthyroidism nodules and hyperparathyroidism. Imaging and biochemical testing guide diagnosis and surgical planning. Endocrine therapy and surgery address functional and structural disease.