Sky,

  

. a UNIVERSITY OF SASKATCHEWAN
MESS UNIVERSITY HOSPITAL

 

DEPARTMENT OF DIAGNOSTIC RADIOLOGY SASKATOON, SASK.
H.P. KENT. M.8.

Cc.S. HOUSTON. M.D.

S.P.K. TCHANG. M.D.

G.P. GENEREUX. MLO.

S.P. PASTERSHANK, M.D.

Ss. YIP M.D.

K. CHOW. M.D. Sept. 22, 1975

Dr. Joshua Lederberg

Dept. of Genetics

Stanford University School of Medicine
PALA ALTO, California 94304

Dear Dr. Lederberg:

Perhaps my letter of July 22 failed to reach you due to summer absence,
or has been put aside due to more pressing matters. In case it is the

former, may I state my Case o-fain .

As a Professor Of Diagnostic Radiology, I am concerned by the unwise
use of diagnostic radiation, particularly in children and women of the
childbearing age. It is a sad commentary on medical thinking, or perhaps
merely another example of the apocryphal Murphy's Law, that the young
woman with the most vague, atypical and often insignificant symptoms,
receives the largest number of radiographic examinations. The less they
are indicated, the more she receives.

I teach our medical students that the following are not sufficient
indications for radiographs of the pelvic area of women under 45 years: —
the patient expects it; the doctor wishes to appear thorough and not take
a remote risk of making a mistake; for reassurance of the patient; for
the curiosity of the doctor; for supposed medico-legal reasons; as a
substitute for the doctor thinking; for something to do. I am convinced
there is a slight risk to all radiation and that there must be an expected
benefit to be balanced against the possible risk.

Doctors in general and even radiologists, frequently come to me with
questions. The topics of inquiry are most often the maximum acceptable
dose for diagnostic procedures (there isn't any); the problems involved with
the ten-day rule; what to do when there is an inadvertent exposure to the
pregnant woman and is abortion ever indicated; and guidelines for use of
diagnostic radiation in the woman known to be pregnant.

I thought the BEIR report was excellent and feel that the findings
in it should be more widely disseminated to the medical profession to help
them deal with problems such as mentioned above. In this regard I was very
much intrigued by their extrapolations from your interesting calculations,
Dr. Lederberg -2- sept. 22, 1975

which you published as the Foreword to The Mutangenicity of Pesticides,
Concepts and Evaluation (MIT Press, Cambridge, Mass. 1971) and as "Squaring
an Infinite Circle, Radiobiology and the Value of Life" (Bulletin of the
Atomic Scientists 27: 43-45, Sept. 1971).

I have made a further paraphrase and extrapolation of the extrapolation
and would like to use it in the article I now have ready for submission to
the Canadian Medical Association Journal. I would gladly send you the entire
article if you would Tike to see it.

If you could spare the time, I would very much appreciate a phone call
to correct any fallacies in my understanding or calculations. I did not
think it was necessary to divide by the 30 year generation and then multiply
by the same 30 years, and although perfectly correct, thought this could
be left,out of the calculations. It is entirely possible that I have not
fully cmprehended every facet of your argument and that I have in my ignorance
misled“my potential readers.

I would be most appreciative if you would phone me collect at my
office 1-306-343-3041 or at my residence 1-306-244-0742 crrlicirn avd Comunonle

of rw in p . )
Thanking you in anticipation.

Yours sincerely,

OPEGAE

C. Stuart Houston, M.D.,F.R.C.P. (C), F.A.C.R.
CSH/ jm ,

Bnck -