Let us see how many millicuries we will in future be able to turn
out in the week in our new Dublin Radium Institute.[1] We shall
have about 130 milligrammes of radium. In 3.8 days we get 65
millicuries from this—_i.e._ half the equilibrium amount of 130
millicuries. Hence in the week, we shall have about 130
millicuries.
This is not much. Many experts consider this little enough for
one tube. But here in Dublin we have been using the emanation in
a more economical and effective manner than is the usage
elsewhere; according to a method which has been worked out and
developed in our own Radium Institute. The economy is obtained by
the very simple expedient of minutely subdividing the' dose. The
system in vogue, generally, is to treat the tumour by inserting
into it one or two very active
[1] Then recently established by the Royal Dublin Society.
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tubes, containing, perhaps, up to 200 millicuries, or even more,
per tube. Now these very heavily charged tubes give a radiation
so intense at points close to the tube, due to the greater
density of the rays near the tube, and, also, to the action of
the softer and more easily absorbable rays, that it has been
found necessary to stop these softer rays—both the y and ß—by
wrapping lead or platinum round the tube. In this lead or
platinum some thirty per cent. or more of the rays is absorbed
and, of course, wasted. But in the absence of the screen there is
extensive necrosis of the tissues near the tubes.
If, however, in place of one or two such tubes we use ten or
twenty, each containing one-tenth or one-twentieth of the dose,
we can avail ourselves of the softer rays around each tube with
benefit. Thus a wasteful loss is avoided. Moreover a more uniform
"illumination" of the tissues results, just as we can illuminate
a hall more uniformly by the use of many lesser centres of light
than by the use of one intense centre of radiation. Also we get
what is called "cross-radiation,"which is found to be beneficial.
The surgeon knows far better what he is doing by this method.
Thus it may be arranged for the effects to go on with approximate
uniformity throughout the tumour instead of varying rapidly
around a central point or—and this may be very important— the
effects may be readily concentrated locally.
Finally, not the least of the benefit arises in the easy
technique of this new method. The quantities of
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emanation employed can fit in the finest capillary glass tubing
and the hairlike tubes can in turn be placed in fine exploring
needles. There is comparatively little inconvenience to the
patient in inserting these needles, and there is the most perfect
control of the dosage in the number and strength of these tubes
and the duration of exposure.[1]
The first Radium Institute in Ireland has already done good work
for the relief of human suffering. It will have, I hope, a great
future before it, for I venture, with diffidence, to hold the
opinion, that with increased study the applications and claims of
radioactive treatment will increase.