Medical questions & health advice by board certified doctors

"Is it harmful to do a medical study that takes a CT scan of my head?"

ZocdocAnswersIs it harmful to do a medical study that takes a CT scan of my head?


I am a 24 year old male. I am short on money and signed up to do a medical study. They will take a CT scan of my head. Is this dangerous? I do not need one.


Let me first start out by saying that this sounds like a question that you have to discuss with the physician that has signed you up for this study - especially since I don't know for sure exactly what the medical study is trying to look at. Pending what they are studying, they may have different scanning protocols, etc. However, speaking in general terms and not directly to the study protocol (since I don't know the protocol, nor exactly what imaging modalities they are studying) I can give you some general information about different imaging modalities and their different risks. First of all a CT scan stands for "computed tomography". This is an X-ray that is taken and used to compute a 3D image from a series of 2D X-rays taken circumferentially around a single axis. In this case, the patient lies flat on a table (the axis), and the table is passed through the machine that takes circumferential X-rays. An x-ray is a form of ionizing radiation, meaning that by definition there is always a risk of inducing damage to the patients DNA (even if the risk is low), whick can put the patient at higher risk of cancer formation. CT scans can be done with or without IV contrast which some patients have an allergy to (something else to keep in mind). Just as a general reference for radiation exposure of a CT scan; the typical effective dose of a personal scanner (like airport security) is around 0.00025mSv. A regular chest X-ray is 0.1mSv, a CT head is 1.5mSv, and a CT Chest/Abdomen/Pelvis is 9.9mSv. Again I would recommend discussing your concerns with the physician performing the study. Hope this helps.

Zocdoc Answers is for general informational purposes only and is not a substitute for professional medical advice. If you think you may have a medical emergency, call your doctor (in the United States) 911 immediately. Always seek the advice of your doctor before starting or changing treatment. Medical professionals who provide responses to health-related questions are intended third party beneficiaries with certain rights under Zocdoc’s Terms of Service.