Patients, Physicians Unaware of CT Radiation Exposure ?

["Howard Long" <hflong@pacbell.net>]

"theoretically one photon can result in a cancer, period. " (below)

True, but to not add the benefit of stimulating biologic defenses, would be

like a businessman counting only costs, not receipts!



Note also, "[Melanoma] cases tended to have LOWER exposures to UV during

ages 20 to 24 than controls;-" (Moore et al, LLNL '94)



And, "Iraqi killed - 5,000/yr '03, '04"  (but 50,000/yr '92-'02!)



I had dental film all over my X-ray room because patients and physicians

should know. However, I abandoned a study design for detecting hormesis in

smokers, after realizing that the power to detect significant differences

would be low because all would have any good effect from the 1 rem from a CT

( about the yearly dose benefiting most Americans, I believe).



Howard Long MD MPH



----- Original Message ----- 

From: <osuleiman@comcast.net>

To: "John Jacobus" <crispy_bird@YAHOO.COM>

Cc: "Franta, Jaroslav" <frantaj@AECL.CA>; "radsafe"

<radsafe@list.vanderbilt.edu>

Sent: Saturday, May 08, 2004 1:32 AM

Subject: RE: News Article: Patients, Physicians Unaware of CT Radiation

Exposure





> The fundamental problem is that ALARA is not practiced, i.e. how can one

give a patient as low as reasonably achievable when many do not even know

the radiation dose.

>

> Most medical exams can be justified on an individual basis, even a 10 mSv

effective dose, which is on the high end, but when one uses the risk

estimates for cancer, applied to millions of patients, the numbers can be

perceived as high.

>

> The debate over LNT is a waste of precious energy, theoretically one

photon can result in a cancer, period.  Are there modifying factors, yes,

it's also called biological variability, radical scavengers, immune

response, genetic predispoistion, dose rate, soft epidemiological data upon

which risk estimates are based, the list is endless, but theoretially one

photon could result in a cancer.

>

> I think it is long overdue, but there really should be a coordinated

demand for everyone to actually know the radiation dose individuals receive

from a specific exam, be it nuclear medicine or x-ray.  The science exists.

>

> Radiation in Medicine is a valuable tool, and so is the scalpel, both are

also hazardous.

> > The statement should be that there are no demonstrated

> > effects below 10 rem, which does not mean there are

> > none.  In certain subpopulations, like children, there

> > may be greater risks.  CTs are producing the greatest

> > exposures in radiology.  Its use had been doubling,

> > and imaging is replacing some medical procedure.

> > Consider that surgical laparotomy exams are no longer

> > done for suspected appendicitis.  CT exams with a dose

> > of 10 mSv are providing the evaluations.

> >

> > "While the number of visits (to the Emergency Room)

> > remained stable throughout the reporting period, the

> > use of head CT increased from 23.9% to 46% between

> > 1992 and 2000 (p=0.001). In addition, head CT was used

> > more frequently in the older age groups: Children 0-4

> > years of age had 15.9% of the scans, children 5-10

> > years of age had 37.7% of the scans, and patients

> > 11-18 years of age had 45.9% of the scans, he said."

> >

> > The fuss is that 1 rem plus 2 rem plus . . . add up to

> > significant doses in some patients.

> >

>

> > I would also suggest you invest in companies that make

> > CT and PET scanners.

> >

> > --- "Franta, Jaroslav" <frantaj@AECL.CA> wrote:

> > > It would not be uncommon for a patient to get more

> > > than 50 mSv (5 rem).

> > > <SNIP>

> > >

> > > I thought that the current thinking was that no

> > > detrimental effects can be

> > > supported scientifically for any dose less than

> > > about 10 rem.

> > > If that's the case, than why all the fuss about 1

> > > rem CT doses ?



> > > As far as I know, there is no debate about DECREASED

> > > risk of cancer in the medical profession.  It only

> > > appears on this list server.



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