No Subject

["Mike Bohan" <mike.bohan@yale.edu>]

Hi Laura,

My name is Mike Bohan and I'm a Medical Health Physicist/Radiation Safety
Officer at Yale-New Haven Hospital.  Wes Van Pelt posted your question on the
Radiation Safety Listserver and since these questions are usually referred to
me when they come up at Yale, I thought I'd give it a try.

The short answer to your question is don't worry about it.  Although children
are thought to be more sensitive to x-rays than adults, an x-ray for a preemie
requires very little radiation to acquire a good image.  Since these children
weigh only a few pounds, at best, and their bones are not yet fully formed,
the amount of radiation for an x-ray is typically less than 0.01 Rads per
image (Typical technique 2 mAs @ 50 kVp, SID 40"  SSD 35" ~4 mR/image).  At 30
to 40 images the dose is still less that 0.5 Rad total.  This is approximately
equivalent to 2 years of background radiation from natural sources.  It is
also well below any threshold scientifically shown to result in elevated
cancer risk.

The extremely small risk from the radiation exposure is completely overwhelmed
by the risk of NEC (Necrotizing EnteroColitis).  This is a serious condition
which could result in death if not diagnosed and quickly treated.  The use of
x-rays are essential for this diagnosis and to document that the administered
therapy is effective.  Consequently, I would not worry about the radiation at
this point.  

If your son has any chronic aftereffects from NEC or prematurity necessitating
continued x-rays, I suggest you keep a log of the x-rays as they occur and ask
the hospital to provide the anatomical site, technical factors: kVp, mAs, SID,
and exposure (they should be able to provide this).  This will allow you to
review his total dose and you could request periodic review of his radiation
history with his physicians. However, you should remember that without the use
of x-rays your son might not be here to worry about the radiation risks.

I hope this helps,

Mike Bohan

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Michael J. Bohan, RSO   |  e-mail: mike.bohan@yale.edu
Yale-New Haven Hospital |    Tele: (203) 785-2950
Radiological Physics    |     FAX: (203) 737-4252
20 York St. - WWW 204   |    As usual, everything I say may be plausibly
New Haven, CT    06504  |    denied at my employer's convenience ...
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