Thyroid Uptake and Scan Information and Instructions
Redwood Regional Medical Group’s imaging facility is located at 121 Sotoyome Street in Santa Rosa. When arriving, please check in at Room 107 in the main hallway. If you must cancel or reschedule, please notify us at least 24 hours prior to your exam, at (707) 5254040.
General Information: The thyroid uptake and scan will be administered in three appointments over a two day period. It will evaluate the function and appearance of your thyroid gland based on the uptake of a small amount of radioactive iodine. If there is a possibility that you might be pregnant or are currently breastfeeding, please inform the scheduling department or your referring physician before the examination. Wear loose, comfortable clothing, avoiding jewelry around the neck during the imaging appointments.
Prior to your test: Please observe the following in preparation for this test:
Avoid multivitamins containing iodine. (Vicon Forter is okay.) Avoid any products with red, orange, or brown food dyes. Many of these contain iodine. Most foods labels do not specify which red dye is used. Red dye FD&C #40 is okay. Avoid food items with carrageen, agar, algin, and alginates. Avoid restaurants and fast foods, as there is no way to determine which restaurants use iodized salt. Check with your physician before making any changes in medications.
Also, there are several substances that may affect the iodine uptake values of your scan. They are listed here. With your doctor’s approval, it is suggested you discontinue any use of these substances or procedures for the time listed to the right of each category.
Adrenocorticosteroids
Perchlorate
1 week
Bromides
Propythiouracil (PTU)
1 week
Cordarone
Methimazole
1 week
Mercurials
Tapazole
1 week
Nitrates
Thiocyanate
1 week
Iodine solution (Lugol’s)
Liotrix
2 weeks
Liothyroinine Sodium
Pima
2 weeks
Supersaturated potassium iodide (SSKI)
Triostat
2 weeks
Thiiodothyronine (Cytomel)
2 weeks
Amiodarone
Unithroid
4 weeks
Amour
Levothyroxine
4 weeks
Levothroid
Levoxyl
4 weeks
Thyroid extract (Synthroid, Proloid)
Intravenous x-ray contrast agents (IVP, CT, Venogram)
2 months
Oral cholecystographic agents
2 months
Oil based contrast used for Bronchograms and Lymphangiograms has a long-term influence on iodine uptake values. Please contact our radiologist if you have had one of these exams within the last few years. Please follow a low iodine diet for one week prior to the exam. This will help deplete the body of its natural stores of iodine and make the radioactive testing or treatment more effective. (Please see the meal-planning suggestions and avoidances at the end of these instructions.) The first day of your test: On your first visit you will be asked to swallow a capsule that contains a small amount of iodine. Please do not eat any foods four (4) hours prior to your appointment time. You may drink water or a small amount of clear juice if necessary. You will be asked to withhold food for an additional hour after taking the capsule to allow time for digestion. You will be released and may go about your normal routine but will need to return about six (6) hours later. Your second visit will take about 20 minutes to collect images and measurements. The second day: You will return the following morning for more imaging and measurements that will take about 10 minutes.
LOW IODINE DIET Here are some suggestions to assist you with meal-planning:
Milk and Dairy Products
Food Allowed (No Salts)
Foods to Avoid (Salts)
Non-dairy creamer
Cheese, Cottage Cheese Custard Egg, Egg substitute Eggnog Ice Cream, Yogurt Milk, Evaporated milk Pudding Sour Cream
Meat and Meat Substitutes
Fresh beef, chicken, lamb, pork, turkey, veal
Bacon
Unsalted peanut butter
Corn beef Hot Dogs, Luncheon meats Regular peanut butter Sausage
Fish
Fresh fish allowed
Canned tuna Kelp Sardines Seaweed Shellfish
Diet Cont.
Food Allowed (No Salts)
Foods to Avoid (Salts)
Starch
Bread (