Does iodine-123 emit gamma rays?

The isotope’s half-life is 13.22 hours; the decay by electron capture to tellurium-123 emits gamma radiation with a predominant energy of 159 keV (this is the gamma primarily used for imaging).

What is the purpose of iodine-123?

Iodide I-123 is a radiopharmaceutical diagnostic agent used for the evaluation of the thyroid function and/or morphology. Iodide I-123 (as sodium Iodide I-123) is a radioactive isotope of iodine used in nuclear medicine for the diagnostic study of thyroid disease.

What is the decay constant for I-123?

Sodium Iodide I 123 decays by electron capture with a physical half-life of 13.2 hours. The photon that is useful for detection and imaging studies is listed in Table 1. lKocher, David C., Radioactive Decay Data Tables, DOEITIC-11026, 122, (1981) The specific gamma ray constant for I 123 is 1.6R1hr-mCi at 1 em.

What is a normal thyroid uptake percentage?

The normal values of thyroid uptake of radiotracer are 3 to 16% at 6 hours and 8 to 25% at 24 hours. These values may change according to laboratory standard techniques or patient dietary habits. The thyroid gland can uptake more or less than normal.

Why is iodine-123 used for thyroid imaging?

The gamma emission of 123I allows excellent imaging (≈80% efficiency for a -inch-thick crystal) with low background activity. It provides considerably lower doses of radiation to the thyroid with comparable activity than does 131I. Iodine-123 is the iodide of choice for thyroid imaging.

What is I-123 uptake and scan?

A thyroid uptake and scan is a test that shows how well your thyroid gland is working. By using a small amount of radioactive iodine (I-123) tracer, the physician can see how your thyroid gland absorbs iodine. This test can determine if you have an underactive, normal or overactive thyroid.

Why is iodine 123 used for thyroid imaging?

When can I go back to work after radioactive iodine treatment?

The radiation safety physicist will tell you when you can go back to work. This is usually 1 to 2 days after your treatment depending on what kind of work you do, and how close you’ll be to other people.

What is I 123 uptake and scan?

What is a normal thyroid scan?

A thyroid scan uses a radioactive iodine tracer to examine the structure and function of the thyroid gland. This test is often done together with a radioactive iodine uptake test. This image shows the enlargement of the thyroid gland and extension down behind the breastbone (retrosternal space).

What is a 123 scan?

123Scan is an easy-to-use, PC-based software tool that enables the quick and easy set-up of Zebra scanners. With over 600,000 users worldwide, this is the single utility you will need to setup your Zebra scanner.

What are the dangers of iodine-123?

Large doses of Iodine-123 maybe toxic to the thyroid gland and surrounding tissues. Iodine-123 may cause hypothyroidism and other thyroid disfunctions, including thyroid cancers.

What should your TSH level be with no thyroid?

TSH normal values are 0.5 to 5.0 mIU/L. Pregnancy, a history of thyroid cancer, history of pituitary gland disease, and older age are some situations when TSH is optimally maintained in different range as guided by an endocrinologist. FT4 normal values are 0.7 to 1.9ng/dL.

What are the side effects of iodine-123?

Common side effects of ioflupane I-123 may include:

• pain, swelling, burning, or irritation around the IV needle;
• headache;
• dizziness, spinning sensation;
• dry mouth; or.
• nausea.

Can I eat before a thyroid uptake scan?

Please be sure not to eat or drink anything 2 hours prior to your first appointment (you will also need to refrain from eating or drinking for 2 hours following your appointment—see below for further exam preparation details). You will then return to the department at the same time on the following day for imaging.

How does xenon-124 decay into xenon 123?

Xenon-124 absorbs a proton and immediately loses a neutron and proton to form xenon-123, or else loses two neutrons to form caesium-123, which decays to xenon-123.

How do you make 123xe iodine?

Another method is to bombard iodine-127 (127I) to produce 123Xe and let this decay to 123I. Contamination with 124I may increase the radiation dose; because 124I is long lived, its proportion in an 123I preparation increases with time.

Is radioiodine 123 I safe to use for CT scan?

The dose of radioiodine 123 I is typically tolerated by individuals who cannot tolerate contrast mediums containing larger concentration of stable iodine such as used in CT scan, intravenous pyelogram (IVP) and similar imaging diagnostic procedures. Iodine is not an allergen.

What is the difference between iodine 123 and 131 I?

The gamma emission of 123 I allows excellent imaging (≈80% efficiency for a ½-inch-thick crystal) with low background activity. It provides considerably lower doses of radiation to the thyroid with comparable activity than does 131 I. Iodine-123 is the iodine of choice for thyroid imaging ( Fig. 4-1 ).