Answer to Question #13046 Submitted to "Ask the Experts"

Category: Nuclear Medicine Issues — Diagnostic Nuclear Medicine

The following question was answered by an expert in the appropriate field:

Q

My fiancé is getting a procedure done called NM myocardial perfusion single photon emission computed tomography (SPECT). I learned the radiotracer being used is technetium-99m (99mTc) Myoview. We will have a newborn baby (less than one month old) at that time. If we want to be extremely cautious, for how long do you recommend my fiancé avoid being around the baby or me since I am breast-feeding? I love your organization and appreciate your guidance.

A

Congratulations on your new baby.

The risk to you and your baby from your fiancé's procedure is very low. There is no special precaution or radiation safety instruction required by regulatory agencies for 99mTc myocardial perfusion study given the very low risk presented to family members from daily interactions with the patient. If the study would be provided to a breast-feeding mother, the mother would only need to stop breast-feeding for 24 hours after the study and could resume breast-feeding after the 24-hour interruption. This short length of this break puts the risk into perspective and tells us how low the risk is.  

To be extremely cautious, here are some suggestions. Time and distance are the most important elements of reducing radiation exposure. The shorter the time spent near your fiancé, and the larger the distance away, the less your and your infant's dose would be. That said, the simplest precaution to take would be for your fiancé to remain a meter or more away for the first 24 hours (one day) after the injection, and for him to not hold the baby for the first 48 hours (two days) after the injection.

Also, your fiancé will excrete most of the radioactivity through feces and urine, with some very, very small fraction being excreted through sweat and saliva. After about 30 hours, there will only be 1% of the original radioactivity still remaining in your fiancé's body. Regular hand washing and showering can significantly reduce any risk of contamination of your surroundings, but the consequences of contamination are very low, and will not contribute significantly to your or your baby's dose. Since you are breast-feeding, and want to be extremely cautious, you may also want to avoid kissing your fiancé for the first 48 hours.

Barbara Hamrick, CHP, JD
 

Ask the Experts is posting answers using only SI (the International System of Units) in accordance with international practice. To convert these to traditional units we have prepared a conversion table. You can also view a diagram to help put the radiation information presented in this question and answer in perspective. Explanations of radiation terms can be found here.
Answer posted on 18 September 2019. The information posted on this web page is intended as general reference information only. Specific facts and circumstances may affect the applicability of concepts, materials, and information described herein. The information provided is not a substitute for professional advice and should not be relied upon in the absence of such professional advice. To the best of our knowledge, answers are correct at the time they are posted. Be advised that over time, requirements could change, new data could be made available, and Internet links could change, affecting the correctness of the answers. Answers are the professional opinions of the expert responding to each question; they do not necessarily represent the position of the Health Physics Society.