ON THE RADIO-THERAPEUTICS OF RINGWORM. SABOURAUD. (_Ann. de Derm. et
de Syph._, July, 1904, p. 577.)
In a previous paper (published in January, 1904, in the _Annales de
l’Institut Pasteur_) Sabouraud had proposed a method of treating
ringworm with X-rays, which he sums up as follows: “The application in
one sitting upon a given point of the scalp of a quantity of X-rays
equal to 4-1/2-5 H-units of Holzknecht is made; fifteen days later a
complete epilation will occur on the region treated, healthy as well as
diseased hairs being shed. New and healthy hair will commence to grow
ten weeks after the treatment, and will be completely restored within
ten weeks. The infectivity of the disease will cease with the fall of
the last diseased hair, within twenty-five days at latest of the
treatment.” This formula, Sabouraud maintains, has been amply proved to
be true by his experience of the six months which have intervened since
his paper of January, 1904. Some very striking results are quoted. Thus
while in six months before this treatment was adopted 57 patients were
discharged as cured, in the past six months 134 such patients were
discharged; moreover, a very large number of patients were treated
without admission and also cured. An entire section of the hospital,
consisting of one hundred beds set apart for favus cases, has been
closed and will be converted to the uses of general medicine, as being
no longer required for its former purpose.
Certain additional knowledge has been afforded by the experience of the
past six months, which may be stated in the following practical rules:
The penetration of X-rays is proportional to their number; the more
penetrating they are, the more numerous they are. The danger of X-rays
is proportional to their penetration; it is thus more dangerous to
handle X-rays of 8°-11° (on Benoist’s radio-chromometer) than rays of
3°-5°. Now tubes change progressively with use and these changes are
marked by colour changes in the glass. At first, after about ten hours’
use, the tubes take a violet coloration; with this there is no
impairment of function. But with further use, after about thirty hours,
a brown tint becomes marked, and the tube is said to be “smoked.” With
this change it becomes increasingly difficult to obtain rays of a low
degree of penetration. For epilation rays of all degrees of penetration
serve equally well; rays of 3° are as effective as rays of 11°, but the
treatment must be for a longer time. Thus a tube working at 3° caused an
epilation in twenty-five minutes. The same epilation would result in
eleven minutes from a tube at 8°-11°; and if one used the latter tube
for twenty-five minutes, a dermatitis would result. This is entirely
unnecessary for epilation and is attended by mischievous consequences,
even when quite slight, and must be avoided. All forms of dermatitis,
except that of transient erythema, produce permanent baldness. Permanent
alopecia may also result without dermatitis in cases where the amount of
X-rays given has been insufficient to cause epilation, and a second
_séance_ has been necessary. In this case certain hairs will have
received a dose beyond the maximum for safety, and these will be
permanently destroyed. For safe working, it is necessary to have a
measure of the rays coming from the tube at any given time; and the
measure must be constant for every variety of tube. This is obtained by
certain colour changes taking place in specially prepared substances,
these changes being proportional to the amount of X-rays derived from
the tube. The pastilles of Holzknecht have been used for this purpose,
but they are a secret preparation, expensive, and not everywhere
procurable. Sabouraud has devised small discs made of paper which is the
same as that used for screens and is coated with a preparation of
platino-cyanide of barium. These discs change in colour in a fixed
manner, comparable from time to time with test-colours, and their use
makes it impossible, with care, to overstep the limits of safety.