CT scan radiation

[NK346f2849X127d8bca260]

My son is 16 and after seeing paediatrician he is having investigations to see if he has CF.
His chest X-ray showed markings and paediatrician wants a CT scan of his chest for further detail.
DS is worried about the radiation exposure, paediatrician said it was equal to 10 chest X-rays, but I thought it was far more than that. He has had a CT scan of his head when he was 5 as well.
I feel that it is important for him to have it, as obviously if it is CF he needs to be on correct treatment...DH is no help as he mentioned the radiation dose to DS

The doctor would not recommend the scan if they didn't think it necessary. I'm sure the risk of having undiagnosed CF is much greater than the risk of a single chest CT.

The radiation dose from a chest CT is equivalent to 3.6 years background radiation.

Why are they suggesting a ct scan to test for cf? The standard test is a sweat test which is totally non invasive. From that blood tests can be carried to check for faulty genes

There's a useful table here which shows typical effective doses from different X-ray examinations. It's a bit old, and the doses for everything are probably a bit lower now, but it's a reasonable ball-park.

CT chest is about 8mSv, which is about the same amount of radiation as the average person in the UK is exposed to from background radiation in about 3.6 years. It's relatively high for a medical scan, but in the grand scheme of things, I'd be much more concerned about the health problems that are behind this referral.

(An ordinary chest X-ray is about 0.02mSv, so you are right that it is a lot more than ten times.)

The medical staff (paediatrician and a radiologist - an expert in medical imaging who understands radiation risk) will weigh up the risks from the radiation and the benefit that your DS would expect to get from the CT.

The risk from this CT scan is independent of the head CT he has already had. The decision over whether that was justified (in terms of risk and benefit) is completely separate from this decision.

Hope that helps - do ask if you want me to clarify.

mintyneb
The CT scan is because of streaking on chest X-ray, she wants to see if it is CF related.
He is a known carrier of a rare mutation but has had a lot of problems with stomach/bowels over the last two years, also a lot of colds. Paediatrician has sent bloods to Manchester seven weeks ago for extended mapping as she is wondering if there is another mutation out there!
His two sweat tests have come back at 59, so top end of intermediate.

Thank you spin for the info...I agree with paediatrician and feel that the CT is necessary, I am worried about lung damage and want him on the appropriate treatment to prevent any more.

Ah ok. The implication there then is that cf scarring is identifiable in a particular way?

My 10yo DD has cf but she was diagnosed as a baby so we've been fortunate to have her treated correctly from the start.

I'm sure you've explored all this already but have you had any contact with a team at one of the specialist cf centres? I've heard that sometimes folks with 'borderline cf' are on their books and treated as if they have the condition even if its not 100% certain they do.

She said the streaking was CF related but can be seen in severe asthma....he has extremely mild asthma! The CT can apparently tell if it is one or the other because of more detail.
We are seeing paediatrician in June to discuss what her plans for him are, I do hope bloods will come back by then.
He has also got extremely low vitamin D levels, she said that was also a CF flag..he has been prescribed supplements.

If you haven't had any contact with a cf centre yet, I would definitely recommend one. My DD has recently had her annual review which included:

Chest x-ray; lung function; LCI test; bone density scan; blood tests including all the usual tests plus vitamins and immunity tests; glucose monitoring test; liver ultrasound

It's full on but obviously very thorough which means her care can be tailored to exactly what she needs. Would be awful if you DS missed out on something he might need