RMI Nuclear Justice Documents

Results

Radiation Effects of Theraneutic Doses of 131 I in the
Thyroid in Clinical Subiects with Hyperthyroidis m

Serial observations have been carried out on selected patients whom we treated
with therapeutic doses of

13

ly for hyperthyroidism.

and studied for many years thereafter.
a minimal dose of i

31

The patients

The important question

I which will bring a hyperthyroid patient to

without ultimately developing hypothyroidism.

The other question

ve been followed
whether there is
euthyroid state
s whether an

inadequate dose of 131; is more inclined to lead to neoplasm forma ion.
Extensive pretreatment data was collected-on each patient sel

special study.

ted for this

The uptake of 131 I by the thyroid, its disappearan e day by day from

the gland, and the amount and the changing chemical form of radioa tivity in the circulation for several weeks, as well as the loss of isotope through the urine for 3
days, have been followed after the treatment dose.

The results ob fained were ul-

timately related to the changes that took place in the clinical pi tture and the degre
of recovery from hyperthyroidism.

These observations provided inf brmation from which

the actual rad dose delivered to the thyroid could be determined.
The therapeutic objective in the use of 1
a euthyroid state and no lower.

31

I was to bring the patient down to

However, some patients developed hypothyroidism

very rapidly in spite of the fact that the dose of 1

31

I per esti

was thought to be appropriate to bring the patient slowly to the

Other patients were relatively unaffected by what was calculated
tive dose.

ed gram of gland
thyroid state.

fo be a fully effec:

The observer accuracy of the estimated weight of the glands was constant.

checked by the same observer who was operating Similar surgical ci ses and saw the
glands.

Multiple doses were required in approximately one-fourth of these patients.

In such cases, the serial studies following a subsequent treatmen | were Tepeated
to see how the behavior of the 131, the second time commared with the first.

When