Question

Richard Neis had symptoms of excessive secretion of PTH (high blood calcium levels), and his physicians were certain he had a parathyroid gland tumor. Yet when surgery was performed on his neck, the surgeon could not find the parathyroid glands at all. Where should the surgeon look next to find the tumorous parathyroid gland?

a) The surgeon should check Richard's spinal cavity.
b) The surgeon should check Richard's oral cavity.
c) The surgeon should check Richard's thoracic cavity.
d) The surgeon should check Richard's abdominal cavity.

Answer 1

If the parathyroid glands are not found in their usual location behind the thyroid, the surgeon should next check Richard's thoracic cavity for ectopic parathyroid tissue.

Step-by-step explanation:

If Richard Neis is experiencing symptoms of hyperparathyroidism due to excessive secretion of PTH (parathyroid hormone) and a tumor in the parathyroid gland is suspected, but the parathyroid glands are not found in their typical location behind the thyroid gland, the surgeon should look for ectopic parathyroid tissue. These can sometimes be found within the thyroid tissue itself, along the path of descent during embryonic development, or within the thoracic cavity, particularly in the mediastinum, the central compartment of the thoracic cavity.

The most common location to find ectopic or supernumerary parathyroid glands, in case they are not located in their usual position, would be the thoracic cavity. Since the parathyroid glands are derived from the third and fourth pharyngeal pouches, they may descend with the thymus into the thorax during embryonic development.

Therefore, if the initial surgery in the neck fails to locate all parathyroid tissue, the surgeon should generally proceed to explore the thoracic cavity for the ectopic parathyroid tissue that may be causing the hyperparathyroidism and accompanying high blood calcium levels.