Wellness Tools. A gamma probe is placed over the thyroid gland in the neck to measure the amount of radioactivity in the thyroid gland. On the First Day: You will be asked to swallow a small amount of radioactive iodine (or tracer) in capsule form. Scan - thyroid; Radioactive iodine uptake and scan test - thyroid; Nuclear scan - thyroid; Thyroid nodule - scan; Goiter - scan; Hyperthyroidism - scan . The first uptake is usually done 4 to 6 hours after you take the iodine pill. Radioactive iodine-123 (I-123) is the usual isotope used to take pictures and determine the activity of the intact thyroid gland (Thyroid Scan and Radioactive Iodine Uptake, RAIU), since it is harmless to thyroid cells. This will ensure absorption of the radioiodine administered orally in capsule form. How the test will feel: There is no discomfort. Allergy. The RAIU test often is done along with a thyroid scan, which shows if the tracer is evenly spread in the gland. A radioactive iodine uptake (RAIU) test uses a radioactive tracer and a special probe to measure how much tracer the thyroid gland absorbs from the blood. The atom is the smallest unit of an element. A similar test is the thyroid scan. One test is called a thyroid scan and radioactive iodine uptake test. On the Second Day: The test can show how much tracer is absorbed by the thyroid gland. Alternative Names: Iodine uptake test; RAIU. Special considerations: The radioactive iodine is excreted in the urine. Healthwise, Incorporated, disclaims any warranty or liability for your use of this information. For the scanning, you are asked to lie on a table while the scanner is placed over the neck. After a time (usually 6 and 24-hours later), a gamma probe is placed over the thyroid gland to measure the amount of radioiodine uptake in the thyroid gland. DefinitionRadioactive iodine uptake (RAIU) tests thyroid function. Steps to Prepare for the Radioactive Iodine Uptake Test You will be asked to fast for 8 hours before the iodine test. Alternative Names. Radioactive iodine uptake (RAIU) tests thyroid function. An RAIU test measures the amount of tracer taken up by the thyroid gland at certain times after the tracer is given. For both types of test, a small amount of a weakly radioactive substance, known as a radionuclide, is either injected into a vein or given to you as a pill . The study is acquired using a small amount of radioactive iodine (123 I) that has no side effects due to radiation exposure. March 31, 2020, Author: Healthwise Staff Medical Review: E. Gregory Thompson MD - Internal Medicine Kathleen Romito MD - Family Medicine Alan C. Dalkin MD - Endocrinology, Medical Review:E. Gregory Thompson MD - Internal Medicine & Kathleen Romito MD - Family Medicine & Alan C. Dalkin MD - Endocrinology. Definition: Radioactive Iodine Uptake, or RAIU, is a test of thyroid function. The RAIU test often is done along with a thyroid scan, which shows if the tracer is evenly spread in the gland. Radioactive iodine uptake (RAIU) tests thyroid function. If you will be treated with a therapeutic I131 dose after the uptake and scan, please review the radiation safety information. Drugs that increase results include barbiturates, estrogen, lithium, phenothiazines, and thyroid stimulating hormone. No special radiation precautions are necessary after a thyroid scan or RAIU. During an uptake test, a radioactive iodine tracer is given to show how well your thyroid works. RN COMPREHENSIVE PREDICTOR NURSING - STUDY GUIDE What can be delegated to Assistive personnel (AP)? The RAIU test often is done along with a thyroid scan, which shows if the tracer is evenly spread in the gland. During an uptake test, a radioactive iodine tracer is … Taking a look at the thyroid can help to diagnose hyperthyroidism and the possible cause (often Graves’ disease). Its uncertainty affects how much of a true change in RAIU can be detected as well as appropriateness of the therapy dosage upon which it is based. It shows how well your thyroid is functioning. A Word From Verywell Radioactive iodine treatment can be a very effective method of addressing thyroid disease. Menopause. The exam takes place in two parts: the first day, you will swallow a radioactive How the Test is Performed. When you first arrive to the nuclear medicine department the technologist will explain the exam and you will be asked to take two radioactive iodine capsules. This test takes about 10 minutes. Radioactive iodine uptake test is a type of nuclear test performed to evaluate thyroid function. The RAIU test is also used as a follow up to RAI therapy to verify that no thyroid cells survived, which could still be cancerous. Just before the test, you will remove your dentures (if you wear them) and all jewelry or metal objects from around your neck and upper body. How the test is performed: RAIU is a type of nuclear test that measures how much radioactive iodine is taken up by the thyroid gland in a given time period. This amount of radioactivity is compared with the original dose of radioactivity and reported as a percent of the original dose. Radioactive iodine uptake test. A radioactive iodine uptake test, or RAIU, is typically performed with a thyroid scan to help determine thyroid health and functioning. A similar test is the thyroid scan. How the Test is Performed . Another uptake is usually done 24 hours later. The second type, a radioactive iodine uptake test, is performed to see if your thyroid is functioning normally and to determine why thyroid hormone levels may be elevated. After swallowing it, you wait as the iodine collects in the thyroid. A similar test is the thyroid scan. A thyroid scan uses a radioactive iodine tracer to examine the structure and function of the thyroid gland. This test is also not recommended for breastfeeding women or young children. That's the case even with the low-level radioactive tracer used for this test. Increased (greater than 35% at 24 hours is considered elevated): Additional conditions under which the test may be performed: What the risks are: The risk is minimal. It measures how much radioactive iodine is taken up by your thyroid gland in a certain time period. The test is done in this way: You are given a pill that contains a tiny amount of radioactive iodine. Your provider could use a few tests to look at your thyroid. The thyroid gland absorbs iodine and will absorb the radioactive tracer. After a time (usually 4 and 24-hours later), a gamma probe is placed over the thyroid gland to measure the amount of radioiodine uptake in the thyroid gland. The RAIU test often is done along with a thyroid scan, which shows if the tracer is evenly spread in the gland. The test can show how much tracer is absorbed by the thyroid gland. © 1995-2021 Healthwise, Incorporated. Radioactive iodine uptake test is a type of nuclear test performed to evaluate thyroid function. Image. This test is not done for pregnant women because of the chance of exposing the baby (fetus) to radiation. For example, you may have uptake measurements at … This helps your doctor know if the thyroid gland is working properly. Radioactive iodine uptake test is a type of nuclear test performed to evaluate thyroid function. This test is done in 2 parts on 2 separate days. You will be given radioactive iodine (I-123 or I-131) in liquid or capsule form to swallow. 6 hours: 3 to 16% 24 hours: 8 to 25% Note: Some laboratories only measure at 24 hours. How long does the test take? Anytime you're exposed to radiation, there's a small chance of damage to cells or tissue. A history of iodine (contrast dye) allergy does not necessarily contraindicate testing, although history of allergy to dietary iodine (or shellfish) may contraindicate this test. The radioactive iodine uptake test is a type of scan used in the diagnosis of thyroid problems, particularly hyperthyroidism.It is entirely different from radioactive iodine therapy (RAI therapy), which uses much higher doses to destroy cancerous cells. It measures how much radioactive iodine is taken up by your thyroid gland in a certain time period. Find the cause of an overactive thyroid gland (hyperthyroidism). Radioactive Iodine Testing Depending on the dose, radioactive iodine can kill a portion, or all, of your thyroid. Alternative names: Thyroid uptake; Iodine uptake test; RAIU A radioactive iodine uptake (RAIU) test uses a radioactive tracer and a special probe to measure how much tracer the thyroid gland absorbs from the blood. The 2 tests are commonly performed together, but they can be done separately. How the Test is Performed. Thyroid uptake; Iodine uptake test; RAIU. The dosage of RAI determines the length of isolation required. Iodine, in the form of iodide, is made into two radioactive forms of iodine that are commonly used in patients with thyroid diseases: I-123 (harmless to thyroid cells) and I-131 (destroys thyroid cells). The amount of radioactivity is very small and there have been no documented side effects. The test shows either more or less uptake of tracer than normal in the thyroid gland. The test is done in this way: You are given a pill that contains a tiny amount of radioactive iodine. The test can show how much tracer is absorbed by the thyroid gland. Radioactive Iodine Ablation Treatment for Differentiated Thyroid Cancer. For medical advice relating to your personal condition, please consult your doctor. If hyperthyroidism is present, abnormal test results may mean certain conditions are present. The radioactive tracer commonly used in this test is iodine. Cells which are most active in the target tissue or organ will take up more of the radionuclide. The test helps your health care provider see how much radioactive iodine your thyroid has absorbed over a certain time period, usually 6 or 24 hours after taking radioactive iodine. Another scan may be done in 24 hours. Iodine scans are now only used for specific situations in cases of proven thyroid cancer. Thyroid scans can help your doctor determine if your thyroid is working properly. Radioactive iodine uptake (RAIU) tests thyroid function. How to prepare for the test: Fast for 8 hours before the test. The values are then compared. After a time (usually 6 and 24-hours later), a gamma probe is placed over the thyroid gland to … Thyroid uptake; Iodine uptake test; RAIU. • After the uptake and scan, it will take about 1 hour for your therapy dose to arrive. See also "thyroid scan. The amount of radioactive tracer in the thyroid gland is normal. The first uptake is usually done 4 to 6 hours after you take the iodine pill. The patient ingests radioactive iodine (I-123 or I-131) capsules or liquid. Work and Life Balance. There are no special preparation instructions for this scan. In this study, a method of estimating the reproducibility and least significant change (LSC) values for … No special radiation precautions are necessary after a thyroid scan or RAIU. The dosage of RAI is given in millicuries. So be sure to flush the toilet right after you use it, and wash your hands well with soap and water. However, as with any radiation exposure, this test is not recommended for women who are pregnant or breastfeeding. Alternative Names. To test your thyroid gland, radioactive iodine is used. It measures how much radioactive iodine is taken up by your thyroid gland in a certain time period.A similar test is the thyroid scan.