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cALAssociATioN JouRNAL
c AscITo [Nov. 1932
ORAL[o.13
READING WITH CLOSED EYES
By A. H. PIE, B.Sc., M.D.,
Montreal
THE title of this paper does not mean that brain receives the message reversed from what
it is possible to close one's eyes and read a is experienced by ordinary vision, and the im-
newspaper, but it means that a sentence can be pression is received that the object looked at is
read with the eyes closed when that sentence is reversed and turned from left to right.
properly presented to the eyes. It also means By arranging lead letters on a ribbon to form
that a picture can be seen with closed eyes when a sentence, that sentence can be read by passing
a properly prepared picture is presented to the the words one after the other in front of the
eyes. eye. A convenient way for doing this is shown
This is accomplished by making use of the in Fig. 3. The observer looks into an eyecup
x-rays to stimulate the retina. Everyone can fitted on a dental machine, and the ribbon is
have his retina stimulated by x-rays and so see passed in front of his eye. A picture built up
light. Over- 100 observers have been tested and of lead lines and not bigger than one centimetre
everyone has been able to read letters with closed square can be seen in like manner. A simple
eyes. figure of a face can easily be made for this
The method is extremely simple, The first purpose by pricking holes through treatment
essential is that the observer must remain in lead so as to form a face. The face is then seen
total darkness for ten minutes. By that time as a bright dotted face on a black background.
he is able to see light when x-rays strike his Fig. 4 shows the kind of dotted face used for
retina. He may not be able after ten minutes this purpose.
to see letters, but he will after fifteen minutes Stereoscopic vision can be had by pricking a
in the dark. After twenty minutes he can see stereoscopic pair of pictures in treatment lead,
and read the letters and see pictures. No lens as in Fig. 5, and presenting one picture to one
in the eye is necessary. A doctor whose lenses eye and the other to the other eye. By moving
had been removed saw and read the letters as them about till they fuse a stereoscopic effect
clearly as one with his lenses present. The is obtained. In similar manner one could see
doctor without his lenses tried to read the letters a solid body stereoscopically by having two
with his spectacles on and they fluoresced. All x-ray tubes and casting the shadow of the
spectacles fluoresce, and the application of this solid body formed by the left tube into the
interesting fact will be referred to later. right eye, and that of the right tube into the
In Fig. 1 the method is depicted. The x-ray left eye.
tube A sends the rays on to the retina and in
the path of the rays a lead letter T is placed PRACTICAL USES
as near to the retina as possible. When the eye 1. A metallic foreign body in the eye can
is shut it should be touching or almost touching be made to cast its shadow on the retina as in
the upper eyelid. The shadow of this T is Fig. 6. The foreign body A is cast on the
thrown on the retina at T2, and the retina lights retina at B, and the patient sees it as a black
up except where the shadow of the T protects spot in a light field. It is necessary to prepare
it from the rays. If small enough letters are the patient for this by keeping him in total
used, each one being about 1/8th of an inch, a darkness for twenty minutes. If the foreign
short word can be read. body has been already exactly localized the
Now refer to Fig. 2. When one sees an object patient will localize it in the same position,
by daylight that object is focused upside down but turned from right to left, and from above
on the retina and turned from left to right, as down. For instance, if the foreign body is
in Fig. 2; whereas when its shadow is cast on localized in the lower nasal quadrant the
the retina by x-rays it falls as in Fig. 1. The patient will see it in the upper temporal
Nov..
1932]
No.13].nE
Pnuz--. RFADING WITH CLosED EYES
EDNGWT LSDEE
489
8
quadrant. In order to make this localization retina at B and also at C and the patient sees
more exact a brass grid with a central cross two shadows of the single foreign body.
and two circles is placed in front of the eye. 2. Damage to the retina by a foreign body
Fig. 7 shows the construction of this grid. It can be recognized. The damaged part of the
is about one square centimetre in size. The retina will be recognized by the patient as a
patient then sees the foreign body as a black black spot, and its position can be ascertained
mark somewhere on the grid. Suppose the by using the grid. If the foreign body lies
point A represents the shadow of the foreign exactly over the blind spot the patient will not
be able to see it. It is difficult to see the blind
spot, as its presence is lost in the brilliant field
of illumination, just as one cannot see the stars
when the sun is overhead. By using weak
x-rays the blind spot may be recognized.
The field of vision can be mapped out easily
I
.
by using the grid, and the patient can show
!0 .
.
by a diagram on a drawing of the grid what
4 he has seen. This can be done in cases of
complete cataract or opacity of the cornea
when the ordinary method is not applicable.
This method should be of use in neurological
diagnoses, as in brain tumours.
5 A person whose retina is intact but who is
blind from opacity in front of the retina can
see letters and pictures by this method.
When a solid spinning-wheel provided with
a single hole is looked at by this method the
6 individual flashes of the x-ray tube can be seen,
but the impression is obtained that the wheel
is rotating in a direetion opposite to its real
RETIDIA motion.
It is not possible by means of a crystal to see
RETINA 8 the diffraction of x-rays by this method, as the
diffracted rays are too weak to be seen.
body. Then the patient describes the foreign It is probable that a patient suffering from
body as lying on the cross wire AB on the night blindness will not be able to use this
outer circle in the upper area. This locates it method. This has not yet been tested.
to the middle line- below the horizontal. The The fact that glass fluoresces under x-ray
depth of the foreign body could be located by bombardment should be used by the ophthalmo-
triangulation by moving the source of the logist for seeing a piece of glass in, the eye. If
x-rays a known distance and having the source
the ophthalmologist is prepared by remaining
of the x-rays at a known distance. The re- twenty minutes in total darkness, and a power-
lative movement of the foreign body in relation ful beam of x-rays is passed into the eye he
to the movement of the grid would determine should be able to see the fluorescing piece of
the depth of the foreign body. glass in the eye. A small piece of glass might
When a foreign body lies inside the eye it cause so little shadow on a photographic film
can cast only one shadow and the patient sees that it could not be recognized and yet it might
it as single. When it lies outside the eye it fluoresce sufficiently under -x-rays for the
also may cast only one shadow, but if it is seen ophthalmologist to see it. To see glass fluoresc-
as double it is proof that it is outside the eye. ing one must be in the dark for twenty minutes,
This is shown in Fig. 8. for its fluorescence is not strong. Different
The foreign body A casts its shadow on the qualities of glass vary in fluorescence.
490
49
THE GAN-ADIAN
TH CAADA MEIA
T, k&40(IATION JOURNAL
ASOITO Joa [Nov. 1932
No.13
SUTMMARY 5. The field of vision can be mapped out even
1. Reading with closed eyes is described. in cases of complete cataract and opaque cornea.
2. A picture can be seen with closed eyes. 6. Neurological cases should benefit by this
3. A foreign body in the eye can be seen and
located by patient. method.
4. A foreign body outside the eye may be 7. Stereoscopic vision with closed eyes is
seen double. described.
A SEROLOGICAL AND CLINICAL INVESTIGATION OF INDIVIDUALS
EXPOSED TO BR. ABORTUS
By E. P. JOHNS, M.D.,
Chief, Division of Pathology, Faculty of Public Health, University of Western Ontario,
F. J. H. CAMPBELL, M.D., M.R.C.P.,
Associate Professor of Medicine, University of Western Ontario,
AND
C. S. TENNANT, M.D.,
Superintendent, Ontario Hospital,
Woodstock
DURING the last ten years the attention of vincial institution for the care and treatment
physicians has been directed to the problem of epilepsy. This institution obtains its milk
presented by the discovery of an apparently supply from its own cattle, maintained on the
new disease, namely undulant fever, due to in- grounds of the institution, and there is a his-
fection by Brucella abortus. This organism was tory of continuous contagious abortion present
isolated first by Bang,' in 1897, who established in the herd for a long period of time. Agglutin-
its etiological relationship to contagious abor- ation tests on the blood serum and milk whey
tion in cattle. However it was not until Evans,2 of these animals showed the herd to be grossly
in 1918, established the true relationship be- infected. Of 29 cows on the milk line, none of
tween M. melitensis of Bruce, the cause of the blood serums gave an absolutely negative
Mediterranean or Malta fever, and B. abortus of agglutination reaction, and 7 of the specimens
Bang that the possible pathogenicity of this gave an agglutinating titre of 1 - 100 or over.
organism for man was given adequate consider- Samples of milk from 5 of these animals gave
ation. Following this discovery several ob- an agglutinating titre in the milk whey of 1 - 100
servers reported cases of human infection or over.
thought to be due to the abortus (cattle) or suis Carpenter3 was able to isolate Br. abortus
(hog) variety of Br. melitensis, and a new in- from milk in 66 per cent of a group of cows
terest was aroused, resulting in the recognition that either had aborted or had retained the
of the disease as a widely spread pathological placenta at least once during three previous
entity. Although rapid progress has been made gestations. Schroeder and Cotton4 found Br.
in our knowledge of the disease, at the present abortus in the milk of 83.5 per cent of cows
time there is considerable doubt as to the true whose blood serum showed specific agglutinins
incidenee of the condition and the relative path- for the organism. Samples of the pooled milk
ogenicity of the various strains. It was there- used in the institution were examined for iBr.
fore felt that a study of a group of patients abortus by culture and guinea-pig inoculation
known to have been exposed to infection with and the organism was isolated on three occa-
Br. abortus over a period of years would be of sions. When this investigation was commenced
value. the milk used in the institution was not pasteur-
A group of suitable- patients was discovered ized, and as all of the patients were using milk
at the Ontario Hospital at Woodstock, a pro- in some form it was felt that, although there