X-Rays, CTA Scans Risk Question

[AngieBaby77]

Hello everyone. I need some advice and some input. Here's my story and question. It may not sound cancer related at first but it is:

In March I had an MRI and CT scan. The MRI detected a questionable 2mm cerebral aneurysm. The neurosurgeon who reviewed the films could not make a diagnosis either way but said if it was an aneurysm it was too small to mess with and to come back in five years for a followup. I would have gotten a second opinion but he is known as the best of the best in my state.

Recently I applied for health insurance (I am self-employed) and was denied due to 'aneurysm without surgical correction.'

I called the neurosurgeon and he has ordered a CTA scan which is a CT scan with dye I think. The goal is to get a definitive diagnosis so that if in fact there is no aneurysm I can get insured, and if there is we will know to keep an eye on it.

This whole process has been so scary and stressful. Other than the brain issue, I am worried about the effects of too much radiation. I am so scared that all this radiation will cause cancer. I don't know whether to go for this CTA because of this. This year alone I've had:

MRI
Head CT
Two chest X-rays
Sinus X-rays

In the past five years I've had:

Multiple dental, chest and back X-rays
Chest CT scan (it took 30 minutes!)

I had some medical problems in early childhood and know I had a CT scan (at least one) when I was a very young child. I was a preemie and there were brain growth concerns and I know at least one but probably more CTs were done. Luckily the concerns resolved and I grew up healthy (I am 30 years old now)

I wonder if more radiation from a CTA scan will raise my risk of cancer. How risky is it? How much radiation is too much? Should I cancel this? Should I not worry?

Also, are there any supplements I can take to reduce the effects of this radiation or remove it from my body before it damages my cells?

I'm a nervous wreck. In case you didn't notice I also have a severe anxiety disorder and all these medical worries have kicked it into overdrive. I just want to stop catastrophizing this situation but I need some input.

Thanks!
Angela

[Enoch Choi, MD]

Good luck AngieBaby77...  hope the results turn out well for you..

[AngieBaby77]

Thank you so much bigluke, I feel so much better. I had a CT that showed a calcified node years ago and never did get another one as it was deemed benign. This upcoming one is a cerebral CTA and I am still nervous but not so much now.

I talked to the radiology department and they helped reassure me. I am nervous about the results and stuff, but now I am less scared about the radiation/cancer thing.

I really appreciate your input!

Angie

[Enoch Choi, MD]

Hey, bigluke, thanks for encouraging AngieBaby77 to get the kind of reassurance you got.  Great idea!

[bigluke]

I share your concerns (see my post of 10/24).  I spoke with my radiologist about my 5 Chest CT scans over the past 2 years to follow 2 lung nodes, and he was reassuring to me.  Said it was protocol.  Plus, Dr. Choi's excerpt was reassuring to me and should be to you (thank you, Dr).  I wouldn't sweat the amount of time of your CT scan (30 minutes)....my radiologist told me that the first several minutes of mine was a "topogram" to set the scanner, and delivered only a small fraction of radiation.  As long as your doctor knows about your previous tests, it's probably the best for you and you shouldn't worry about it.  Easy for me to say....
If you want to discuss further, reply here or email me at ***@****
bigluke

[Enoch Choi, MD]

An MRI does not expose you to any radiation, it only measures the magnetic resonance of the water in your body.

You can compare the specifics from your CT scans to the following information (i can't tell you how much radiation you recieved, you have to find out from your radiologist since different scans use different levels of radiation)

this is from the CDC site on this page:
http://www.fda.gov/cdrh/ct/risks.html

Risk Estimates

In the field of radiation protection, it is commonly assumed that the risk for adverse health effects from cancer is proportional to the amount of radiation dose absorbed and the amount of dose depends on the type of x-ray examination. A CT examination with an effective dose of 10 millisieverts (abbreviated mSv; 1 mSv = 1 mGy in the case of x rays.) may be associated with an increase in the possibility of fatal cancer of approximately 1 chance in 2000. This increase in the possibility of a fatal cancer from radiation can be compared to the natural incidence of fatal cancer in the U.S. population, about 1 chance in 5. In other words, for any one person the risk of radiation-induced cancer is much smaller than the natural risk of cancer. Nevertheless, this small increase in radiation-associated cancer risk for an individual can become a public health concern if large numbers of the population undergo increased numbers of CT screening procedures of uncertain benefit.

It must be noted that there is uncertainty regarding the risk estimates for low levels of radiation exposure as commonly experienced in diagnostic radiology procedures. There are some that question whether there is adequate evidence for a risk of cancer induction at low doses. However, this position has not been adopted by most authoritative bodies in the radiation protection and medical arenas.

Diagnostic Procedure: Chest x ray (PA film)

Typical Effective Dose (mSv): 0.02 (Effective dose in millisieverts (mSv)

Time Period for Equivalent Effective Dose from Natural Background Radiation : 2.4 days  (Based on the assumption of an average "effective dose" from natural background radiation of 3 mSv per year in the United States.)


Diagnostic Procedure: CT head

Typical Effective Dose (mSv): 2.0 (Effective dose in millisieverts (mSv)

Number of Chest X rays (PA film) for Equivalent Effective Dose : 100 (Based on the assumption of an average "effective dose" from chest x ray (PA film) of 0.02 mSv)

Time Period for Equivalent Effective Dose from Natural Background Radiation : 243 days  (Based on the assumption of an average "effective dose" from natural background radiation of 3 mSv per year in the United States.)



Dr. Enoch Choi, MD
Palo Alto, CA