St
and hand for bone development studies): studies
of aging criteria; speerat examinations of the skin
with color photography of selected lesions: oph-
thalmological studies including slit-lamp observations, visual acuity, and accommodation; audiometric examinations: cardiovascular survey: and
X-rav ewaminations as deemed necessarv.
In 1959, 96 exposed people, including their
childref, and 166 unexposed people were examined on Rongelap.
Cardiovascular Survey.
[In viewofthe possible
association oflate effects of radiation with cardiovascular disease. the following cardiovascular survey was Carried out.
l. Clintcai Aistortes recorded present and past
health and illnesses, especially cadiac and pulmonarysymptoms.
2. Physical examinations included the usual observations in the cardiovascular system in regard to
the rhychm and rate of the heart; the nature of the
heart sounds and murmurs, if present; the size and
shape of the heart by clinical indications; changes
in the arterial walls as observed byinspection of
the retinal arteries and bypalpation of the radial,
brachial, and dorsalis pedis arteries; and the appearanceotthe veins.
3. Instrumental procedures: Systolic and diastolic
blood pressures were obtained with the cuff-tvpe
aeronoid sphygmomanometer. Oscillometry readings were obtained from both legs at calf level by
the Collins type of oscillometer. The highest of the
readings obtained at different pressure levels was
used as a single reading for each subject. Electro-
cardiograms were taken on people 20 years of age
and over (84 unexposed and 38 exposed indi-
viduals), The electrocardiograms were taken by a
Sanborn Direct Writing apparatus which had
been specially shock mounted for field use.* In almost all subjects the electrocardiograms were
taken with 12 leads, to include three standard bi-
polar limb leads, three augmented unipolar limb
leads, and six unipolar or Vchest leads in accord
with the standard 1 2-lead procedure recommended
by the American Heart Association. The tech-
nical qualityof the electrocardiogram was in most
instances relatively good, but there were two
handicaps. The electric power for the instruments
was obtained from a generator on the LST by running a cable ashore to outlets in the various build"We are most grateful to the Medical Equipment Research
Department, US. Army, Fort Totten, N.Y., for use of this instrument on a permanent loan basis.
11855959
ings used for the medical examinations. Induction
currents often caused interference, and grounding
of the instruments at times was difficult. There
were aiso technical variations because of variable
line voltage and amperage. .\-rayfilms of the chest
were taken on selected subjects when indicated.
The number taken was kept to a minimum to
avoid additional radiation of the exposed people,
even though the dose involved was extremely
small. The films were used chieflyfor the studyof
the lungs and, to some extent, for measurement of
heart size and shape. Chest films were obtained on
Ll subjects in the unexposed group and 7 tn the
exposed group.
[t should be pointed out that there was no
standardized basal or adjusted level of physical
activity, such as resting for one hour before taking
the tests. The patients were seen in the course of
the usual examination, as might occur in the out-
patient department ofa hospital.
Arthritis Survey.
During the course of other
studies on the Rongelap population, it was pos;
sible to obtain information on the prevalence of
arthritis and allied phenomena. Since little #
known of the prevalence of these diseases in tropical populations, any such data would be a contribution to the “geographic pathology” of the
arthritides’ besides being of interest in connection
with the possible adverse influence of radiation exposure on degenerative diseases.
X-rays of the hands and wrists were graded for
osteoarthritis on a scale of 1+ to 4+ by the
method of Kellgren and Laurence? as modified by
Blumberg et al.” The same x-rays were used to
detect anv cases of rheumatoid arthritis, other
arthritides, or bony abnormalities.* A small aliquot of serum (0,3 to 0.5 ml) was used to deter-
mine the presence of “rheumatoid factor” bythe
bentonite flocculation test of Bozicevich et al.'° In
this test, a titer of 42 or greater is considered positive, 45 doubtful, and any titer below !16 negative.* A joint examination on each of the Ronge-
lapese was performed by the medical examiners,
and anv individual with significant joint findings
was re-examined by one of the physicians experienced in the diagnosis ofjoint disease. Treatment
of the joint disease was undertaken where indicated.
*We are indebted to the following personnel of the National
Institutes of Health: Drs. R.L. Black, J.J. Bunim, and E.G.L.
Bywaters for reviewing the x-rays, and Dr. K. Bloch for pertorming the bentonite flocculation test.