hi, I have two questions. My first question Is by administering contrast when doing a CAT scan does that increase the amount of msv a person will receive or is the msv the same as without contrast and does the amount of radiation absorb by the organs increase ? For example if an abdominal /pelvic CT scan is 12 msv without contrast , using the same machine if contrast was then given would the total still be 12 msv but the amount of radiation absorbed by the organs be higher with the scan done with contrast as opposed to the one done without contrast ? I also wanted to ask when they say a hip x-ray is 0.6 msv does that mean for only one view or is that for two or even three views ? Thank you

The use of oral or intra-venous contrast material does not increase the radiation dose that the patient receives during a CT scan. If a scan protocol includes scans both without and with a contrast agent, then the radiation dose received will be the sum of the radiation from the two scans. Any contrast material present inside the body does not affect the radiation dose received during that scan. (For more information about contrast agents, see https://www.medicalradiationinfo.org/radiationandmedicine/medical-imaging/contrast-agent-needed/).

Publications that refer to the typical radiation dose for a certain diagnostic imaging exam should state clearly whether the estimate refers to a single picture or a complete examination that may include multiple pictures (otherwise known as "views"). If that information is not given, then the reader is left uncertain about the meaning of the dose estimate. X-rays of the hip typically involve 2-4 views of the hip depending on what the doctor requested.

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How can I find your guidelines for CT radiation limits? I am 60 years old, both my parents with cancer (mom died), and the insurer recommended me to do a hip CT even though the orthopedic doctor clearly wrote MRI in the referral. I understand the insurer’s preference to save money but given my radiation concern, exacerbated by age and family history and the fact that I already had 5 XRay imaging sessions in the past 12 months (three dental and 2 chest views) – I of course prefer to go for the MRI option. I tried to find in your site any official reference (because they said that “according to the AAPM there is zero risk for me”) – but failed. Can you please advise – considering my history, age, and previous xray sessions this year – what would you consider as an exposure to avoid? Is there really a zero risk? Shouldn’t I insist on the MRI – as recommended by the doctor? Basically I see the discrepancy between the clinical doctor and the administrational doctor. And I need to know that they don’t just use your establishment name in order to “disarm” me and save some dollars… Your insights will be highly appreciated. Especially if you would have advised to insist on the MRI (all considered)
Hello, in 2020 when my daughter was 4 1/2 years old she had an ear infection that would not go away with antibiotics, tubes and other treatments. The doctor presented an option of an “Xray” since no other diagnostic procedures were available to due Covid. He pushed to have us do the adenoidectomy but I chose the but when I got to the imaging center I found out it would be a CT of her temporal bone. I went ahead with it with little information from her doctor/the radiologist on radiation exposure. I called recently to get the dose and they said she received 55.75 mgy and the report shows DLP 420 with a note that says “pediatric reductions used.” On the phone, a radiologist from the facility she went to said “ooh, I usually turn it down” when reading the CTDI mgy which has caused me great distress the past year. My question is, should I be concerned about the amount of radiation for this one time exposure for my daughter and approximately how much MSV is this?