Deck 17: Endocrine System

Question 1

On a scan, within the thyroid, thyroid carcinoma is often seen as

A)a hyperactive ("hot") area.
B)a hypoactive ("cold") area.
C)diffuse areas of increased activity.
D)total suppression of gland activity.

Answer 1

a hypoactive ("cold") area.

Question 2

A patient is scheduled for adrenal medullary imaging.The preferred radiopharmaceutical for this study is

A)(¹²³)I-MIBG.
B)(¹¹¹)In-DTPA pentetreotide.
C)(¹³¹)I NP-59.
D)(^99m)Tc-MIBI.

Answer 2

(¹²³)I-MIBG.

Question 3

Thyroid hormone synthesis depends on the

A)trapping and secretion of iodine.
B)regulation and secretion of iodine.
C)organification and regulation of iodine.
D)trapping and organification of iodine.

Answer 3

trapping and organification of iodine.

Question 4

One of the three basic approaches to selecting the dose of ¹³¹I to be administered as therapy for hyperthyroidism is

A)a relatively fixed dose in which the patient receives 50 to 100 mCi of ¹³¹I.
B)a dose based on millicuries delivered per kilogram of thyroid tissue.
C)a dose based on selecting a radiation absorbed dose to the thyroid.
D)a dose based on selecting the organification rate of the thyroid.

Question 5

A patient has a possible pheochromocytoma.The technologist should prepare to image the

A)parathyroid glands.
B)pituitary gland.
C)kidneys.
D)adrenal glands.

Question 6

When performing thyroid imaging, using an electronic zoom

A)is preferred over using a pinhole collimator.
B)can only be used when using ^99mTc-pertechnetate.
C)is NOT preferred over using a pinhole collimator.
D)is best for evaluating thyroid nodules of about 1 cm.

Question 7

When performing a thyroid scan, in addition to an anterior view, oblique views should be taken

A)to provide better information on the localization of the gland.
B)to provide better information on the thickness of the gland.
C)to better define nodules that may be on the anterior or posterior surface.
D)to demonstrate nodules, if any, in more than one plane.

Question 8

A patient receives a thyroid ablation dose of 75 mCi of ¹³¹I.In the United States, according Nuclear Regulatory Commission (NRC) regulations, the patient

A)must remain isolated in the hospital until the calculated dose is less than 30 mCi.
B)can be released from the hospital.
C)can be released only if he or she lives alone and therefore will not expose others to radiation.
D)must remain in the hospital for observation until the calculated dose is less than 30 mCi but does not have to be isolated.

Question 9

A patient's thyroid gland is known to have developed but not to have migrated into the usual location.On the thyroid scan, the technologist would most likely see the patient's thyroid

A)in a substernal position.
B)at the base of the tongue.
C)astride the thyroid cartilage.
D)condensed in the isthmus.

Question 10

When using a ^99mTc-MIBI double-phase study for imaging the parathyroid gland, after the early phase, the technologist should repeat images

A)20 to 30 minutes after injection.
B)40 to 60 minutes after injection.
C)90 to 120 minutes after injection.
D)24 hours after injection.

Question 11

When looking at the blood test results in a chart of a patient with hyperparathyroidism, a technologist will most likely see evidence of

A)excessive catecholamine.
B)elevated serum calcium.
C)an excess of glucosteroids.
D)elevated cortisol levels.

Question 12

After a total thyroidectomy, a patient is referred to the nuclear medicine department for imaging.For effective evaluation and identification of residual thyroid tissue or tumor, the technologist should review the patient's recent history to determine if the patient has taken steps to raise the plasma

A)TSH level.
B)TRH level.
C)TBG level.
D)T₃ level.

Question 13

The radionuclide therapy used for the treatment of either hyperthyroidism or thyroid carcinoma is

A)(^{123S1S1)P0I.
B)(125S1S1)P0I.
C)(131S1S1)P0I.
D)(123S1S1)P0I-MIBG.}

Question 14

Secondary hypothyroidism is the result of a deficiency of

A)T₃.
B)TBG.
C)TSH.
D)TRH.

Question 15

The overall function of the thyroid gland is regulated by the hypothalamus-pituitary axis via

A)T₄ and T_3.
B)TRH.
C)TBG.
D)TSH.

Question 16

When the thyroid gland is the source of excessive thyroid hormone, is diffusely large, and is homogenously active, it is characteristic of

A)Graves' disease.
B)Plummer's disease.
C)multinodular goiter.
D)thyroid cancer.

Question 17

When a patient is administered ^99mTc-pertechnetate for a thyroid scan, the technologist should take the static images

A)immediately upon injection.
B)5 to 10 minutes after injection.
C)15 to 20 minutes after injection.
D)30 minutes after injection.