The Eye in its Relation to Health
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By Chalmer Prentice, M.D.
Chicago, A.C. McClurg & Company, 1895
Transcription (c) A. Wik, 2004

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        | Chapter V |  pages 58-67
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WE step upon a rough pebble.  It hurts.
The fact is, that when the nerves of any
part of the body come in contact with any sub-
stance with sufficient force, that contact produces
an impulse or current which traverses the nerves
to the brain or central nervous system.  This cur-
rent sent from the outside or periphery to the
central nervous system, is called an afferent cur-
rent.  The nerve-center receives this afferent
impulse, and responds by generating and sending
back to the parts and their surroundings that
were originally interfered with, a current or
impulse which is called an efferent current; it is
also called reflex, being sent back as an image of
an object is sent back from a mirror.  In medical
practice we meet with many serious disturbances
arising from what we call reflex causes.
  Frequently has it occurred in the experience of
the dentist, that in removing a diseased tooth, he
has also removed the immediate cause of a
serious neuralgia, some form of headache or other
nervous disorder; the gyn‘cologist records many
instances where displaced organs have been the
cause of reflex diseases in other parts of the body;

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the catarrh specialist has found enlarged or
hypertrophied turbinated bones to have been the
cause of serious reflex diseases; the rectal
specialist has recorded many important cures of
various diseases in other parts by the relief of
some local disease.  Pathology records similar
reflex diseases to an extensive degree and also
relief by a correction of the local disturbance;
and the latter has sometimes been regards as
the primary cause of the reflex disease, but this
conclusion is in all cases erroneous.  For
example, let use suppose that ovaritis gives rise to
some reflex disease; the fact that the ovaritis is
itself the result of some prior cause shows that,
as a causative agent, it cannot be primary.  So
numerous have been such cases and their relief
through each separate branch of orificial surgery,
that some in each department have become so
enthusiastic as to believe that nearly all diseases
find their origin through the disturbances found
in their particular line of work.  Any and all of
these views, taken at first sight and considered
separately, have apparently much evidence in
their favor; but that they are all erroneous is
evident from the fact that while these reflex
troubles had resulted from the special diseases
which were treated, these special diseases them-
selves must each have had a cause which must
still be accounted for.  Consequently, any theory

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which relies on some diseased condition as the
fundamental factor in the origin of disease, must
necessarily be wrong, from the fact that the pri-
mary disease is itself still unaccounted for.
  I wish to be distinctly understood as advo-
cating the importance of correcting all such
disturbances locally, as well as removing the
cause of their origin.  The relief that is af-
forded by giving them attention, is in many cases
truly wonderful.  What I wish to point out par-
ticularly is the origin of the LOCAL disturbance,
for it may be a secondary or tertiary cause of
reflex; and if we do not dip still further into the
mystery of our trouble, that which was the pro-
moter of the primary local disturbance will turn
in some other direction and continue its devasta-
tion of the nerve-centers, and the patient, although
from time to time relieved of various local diffi-
culties, will be forever a sufferer.  This is fairly
substantiated by the cases of a large number of
nervous women who have submitted to a removal
of the ovaries for the relief of nothing more than
chronic ovaritis.  If the patient recovers from
the operation, it is usually recorded as a success-
ful one.  True, the local disturbances have been
relieved, as rheumatism in the leg would be by
amputating the limb; but the central irritation
that gave rise to it generally continues and
expends its fury in some other direction.  At

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least, this has been my observation in no less
than eighty-four cases.  This unsexing of women
because of no other disorder than chronic
ovaritis, will in a great majority of cases be
abandoned; for a more perfect general relief from
these troubles will be found in less stringent
measures.  Clinical experience has repeatedly
demonstrated the truth of this statement.
  Every local disturbance, to whatever specialty
it belongs, has some cause back of it, some ab-
normal nerve-impulse that gives birth to the
unnatural conditions.  In rectal disease a consti-
pated habit exists which in itself is simply a
lack of impulse to perform the functions of the
bowels.
  Habitual constipation is always an evidence of
nerve-center derangement, a condition in which
there is a failure of the dynamic-center to send to
the bowels a sufficient amount of motive-force to
perform the function of absorption, secretion and
muscular action, necessary to carry on the daily
offices of health in these parts.  The derangement
is in the nerve-centers, and any relief that is
obtained from this condition must always be
obtained by regulating the action of the nerve-
centers that govern the bowels.  A pill or any
cathartic is taken into the mouth, and passes on
through the stomach into the intestines.  Its
presence there acts as an irritant which sends an

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afferent impulse to the nerve-centers; from
thence is reflected an efferent impulse that car-
ries to the bowels a working motive-force that
sets their various functions in motion and an
action ensues.  Often has the medical practitioner
met with a case of constipation existing in con-
nection with some serious disease that has
resisted the action of the strongest purgatives;
locally, these remedies have reached the bowels;
but the low, disturbed state of the nerve-centers
has been such that they have not been awakened
to respond to the irritant impulse, which was sent.
Sometimes constipation will be the only promi-
nent local defect in general nervous derangement.
In many cases, we find constipation coexistent
with general nervous debility and various forms
of local derangement; but it may always be con-
sidered a nerve-center derangement and the
opposite of chronic diarrhoea, which is due to an
excess of motive-force to the bowels from irritant
causes.  When the motive-forces or impulses
proceed from healthy nerve-centers and pass
along the nerves that carry them to the entire
digestive apparatus, there is perfect secretion,
perfect digestion, perfect absorption and perfect
daily movement constituting health in these parts.
It is the lack of such innervation in some part or
parts which gives rise to the various distur-
bances.

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  The secretion or manufacture of the various
constituent parts of the digestive fluids, such as
pepsin, diastase, lactic acid, hydrochloric acid,
bile, in short of all organic products, is the direct
outcome of the peculiar nature of the nerve-im-
pulses to the various organs, and is largely char-
acterized by the peculiar form and structure of
the parts that do the work.  These are the little
engines, and any alteration in their nerve-impulses
causes a derangement in the products of their
work.  It is easy to conceive of such an abnormal
alteration in the motive-impulses as to produce
uric acid and other abnormal products which are
found in various diseases.  The presence of uric
acid is said to be the cause of certain diseases,
whereas the truth is, that which is the cause of
the uric acid is the primary case of these diseases;
AN ABNORMAL IMPULSE BRINGS FORTH AN ABNORMAL
PRODUCT.
  The results of nerve transplantation are posi-
tive evidence that the function is not characterized
by the peculiarity of the nerve, for we can trans-
plant efferent nerve fibre to the place where
afferent has been without altering the character
or nature of the function.
  But, is there really more than one kind of
nerve-force?  Although we speak of impulses as
motive and sensory, or those that perform functions
of motion and feeling, besides these we also have

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nerve-impulses that are performing the functions
of assimilation, and again those that are perform-
ing more complex organic functions.  Instead of
these varied functions being due to different kinds
of nerve-force, is it not possible that the anatomi-
cal or histological structure of the various parts
in connection with an adequate supply of nerve-
force, is that which dominates the nature of the
function?  If so, only quantity need be consid-
ered in all changes.
  We do not inherit disease, but we inherit those
conditions which give rise to disease, such as
imperfect anatomical structure of parts which,
for the performance of their functions, require
excessive nerve-force; also imperfectly developed
nerve-centers, which are predisposed to localized
irritation.  Thus by heredity we may be liable to
a particular train of diseases, such as consump-
tion, alcoholism, diabetes, Bright's disease, vari-
ous forms of catarrh, with a tendency to that
weak condition which especially renders one a
victim to malarious and contagious diseases.
  "Tubercular consumption is not a local but a
constitutional disease, and calls for general treat-
ment.  Tubercle bacilli do not and cannot cause
consumption in a perfectly healthy individual,
They induce disease only in persons with lowered
vitality, who thus become susceptible to their
influence."

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  The most prominent pathological change in
motor-ataxy or tabes dorsalis is located in the
spinal cord.  Tabes dorsalis is not, as has been
carelessly affirmed, the cause, but it is one of the
results of disease; and the changes in the spinal
column are due to causes anterior to them, affect-
ing the nutrition of these parts, and the sclerosis
follows.  I speak particularly of this, because we
are frequently prone to select some predominant
pathological condition of a disease and attribute
the disease to that as its cause, whereas it is only
one of its results, concomitant conditions, or prom-
inent lesions.  But these pathological conditions
may act as causes for the establishment of still fur-
ther reflex diseases, producing localized disturb-
ances that act as secondary reflexes, the influence
going further and further until we have reflex
causes quite a number of removes from the pri-
mary.
  The fact that great relief has followed the cor-
rection of local disturbances of the rectum, female
organs, nasal passages and local irritation of other
parts of the body, all of which are abnormal
innervations, ought to lead us to expect even
greater relief from the correction of an abnor-
mal innervation through the visual centers, for
they are much more acute than any of those
nerve-centers that preside over and govern the
action of other parts of the body.

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  In determining the cause of a disease, it is
very important to discriminate between exciting
and predisposing causes, for we commit an error
in resting our judgment on some exciting cause
as being the sole element of the disturbance.
This can always be laid down as a wrong conclu-
sion where the same or a similar exciting cause
fails to bring about universally similar results.
If the same exciting causes are brought to bear
on two persons and one is affected by them and
the other not, there is somewhere a difference in
the two individuals.  There is a predisposition in
one which causes him to yield to the exciting
causes.  In the other the predisposition does not
exist.  Whatever may be the disease arising from
an exciting cause, this reasoning will hold good.
  Exciting causes may be a draught of air, wet
feet, exposure to cold, the monthly physiological
processes in women, pregnancy, over-exhaustion,
poisonous gases, malarial and infectious germs,
injuries, excitement, grief, poisonous drugs of
various kinds, opium, cocaine, bromides, mercury,
lead, alcohol, tobacco, and quite an extended list
might be made.  The action of any of these
is emphasized by predisposing causes; for a large
class of individuals in a general sense have
immunity from the effect of some of the above
causes especially the after effects of narcotics and
poisons.  Any investigation of a disease is remiss if

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it stops at exciting causes.  Acting in conjunction
with predisposing causes there may be several
exciting causes that give rise to a disease and its
continuance.  A general neurasthenic condition
will be a predisposing cause; and tobacco, alcohol,
malaria, over-work, change of life and exposure
to cold may all be exciting causes in bringing on
a disease.  Because we have found one prominent
cause for a disease, we should not relax our search
for others.





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        | End of Chapter V |  pages 58-67
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