given for the examination of the eye: The eye, and to a certain extent
the mucous membrane lining the eyelids, may be exposed to view by gently
parting the eyelids with the thumb and forefinger pressed on the middle
of the respective lids. The pressure, it is true, causes the protrusion
of the haw over a portion of the lower and inner part of the eye, but by
gentleness and careful graduation of the pressure this may be kept
within bounds, and oftentimes even the interior of the eye can be seen.
As a rule it is best to use the right hand for the left eye, and the
left hand for the right, the finger in each case being pressed on the
upper lid while the thumb depresses the lower one. In cases in which it
is desirable to examine the inner side of the eyelid further than is
possible by the above means, the upper lid may be drawn down by the
eyelashes with the one hand and then everted over the tip of the
forefinger of the other hand, or over a probe laid flat against the
middle of the lid. When the interior of the eye must be examined it is
useless to make the attempt in the open sunshine or under a clear sky.
The worst cases, it is true, can be seen under such circumstances, but
for the slighter forms the horse should be taken indoors, where all
light from above will be shut off, and should be placed so that the
light may fall on the eye from the front and side. Then the observer,
placing himself in front of the animal, will receive the reflected rays
from the cornea, the front of the lens and the back, and can much more
easily detect any cloudiness, opacity, or lack of transparency. The
examination can be made much more satisfactory by placing the horse in a
dark chamber and illuminating the eye by a lamp placed forward and
outward from the eye which is to be examined. Any cloudiness is thus
easily detected, and any doubt may be resolved by moving the lamp so
that the image of the flame may be passed in succession over the whole
surface of the transparent cornea and of the crystalline lens. Three
images of the flame will be seen, the larger one upright, reflected from
the anterior surface of the eye; a smaller one upright, reflected from
the anterior surface of the lens; and a second small one inverted from
the back surface of the lens.
So long as these images are reflected from healthy surfaces they will be
clear and perfect in outline, but as soon as one strikes on an area of
opacity it will become diffused, cloudy, and indefinite. Thus, if the
large, upright image becomes hazy and imperfect over a particular spot
of the cornea, that will be found to be the seat of disease and opacity.
Should the large image remain clear, but the small upright one become
diffuse and indefinite over a given point, it indicates opacity on the
front of the capsule of the lens. If both upright images remain clear
while the inverted one becomes indistinct at a given point, then the
opacity is in the substance of the lens itself or in the posterior part
of its capsule.
If in a given case the pupil remains so closely contracted that the
deeper parts of the eye can not be seen, the eyelids may be rubbed with
extract of belladonna, and in a short time the pupil will be found
widely dilated.
DISEASES OF THE EYELIDS.
CONGENITAL DISORDERS.
Some faulty conditions of the eyelids are congenital, as division of an
eyelid in two, after the manner of harelip, abnormally small opening
between the lids, often connected with imperfect development of the eye,
and closure of the lids by adhesion. The first is to be remedied by
paring the edges of the division and then bringing them together, as in
torn lids. The last two, if remediable at all, require separation by the
knife, and subsequent treatment with a cooling astringent eyewash.
NERVOUS DISORDERS.
SPASM OF EYELIDS may be owing to constitutional susceptibility, or to
the presence of local irritants (insects, chemical irritants, sand,
etc.) in the eye, to wounds or inflammation of the mucous membrane, or
to disease of the brain. When due to local irritation it may be
temporarily overcome by instilling a few drops of a 4 per cent solution
of cocaine into the eye, when the true cause may be ascertained and
removed. The nervous or constitutional disease must be treated according
to its nature.
DROOPING EYELIDS, OR PTOSIS.--This is usually present in the upper lid,
or is at least little noticed in the lower. It is sometimes but a
symptom of paralysis of one-half of the face, in which case the ear,
lips, and nostrils on the same side will be found soft, drooping, and
inactive, and even the half of the tongue may partake of the palsy. If
the same condition exists on both sides, there is difficult, snuffling
breathing, from the air drawing in the flaps of the nostrils in
inspiration, and all feed is taken in by the teeth, as the lips are
useless. In both there is a free discharge of saliva from the mouth
during mastication. This paralysis is a frequent result of injury, by a
poke, to the seventh nerve, as it passes over the back of the lower jaw.
In some cases the paralysis is confined to the lid, the injury having
been sustained by the muscles which raise it, or by the supraorbital
nerve, which emerges from the bone just above the eye. Such injury to
the nerve may have resulted from fracture of the orbital process of the
frontal bone above the eyeball.
The condition may, however, be due to spasm of the sphincter muscle,
which closes the lids, or to inflammation of the upper lid, usually a
result of blows on the orbit. In the latter case it may run a slow
course with chronic thickening of the lid.
The paralysis due to the poke may be often remedied, first, by the
removal of any remaining inflammation by a wet sponge worn beneath the
ear and kept in place by a bandage; secondly, when all inflammation has
passed, by a blister on the same region, or by rubbing it daily with a
mixture of olive oil and strong aqua ammonia in equal proportions.
Improvement is usually slow, and it may be months before complete
recovery ensues.
In paralysis from blows above the eyes the same treatment may be applied
to that part.
Thickening of the lid may be treated by painting with tincture of iodin,
and that failing, by cutting out an elliptical strip of the skin from
the middle of the upper lid and stitching the edges together.
INFLAMMATION OF THE EYELIDS.
The eyelids suffer more or less in all severe inflammations of the eye,
whether external or internal, but inasmuch as the disease sometimes
starts in the lids and at other times is exclusively confined to them,
it deserves independent mention.
Among the causes may be named: Exposure to drafts of cold air, or to
cold rain or snow storms; the bites or stings of mosquitoes, flies, or
other insects; snake bites, pricks with thorns, blows of whip or club;
accidental bruises against the stall or ground, especially during the
violent struggles of colic, enteritis, phrenitis (staggers), and when
thrown for operations. It is also a result of infecting inoculations, as
of erysipelas, anthrax, boil, etc., and is noted by Leblanc as
especially prevalent among horses kept on low, marshy pastures. Finally,
the introduction of sand, dust, chaff, beards of barley and seeds of the
finest grasses, and the contact with irritant, chemical powders,
liquids, and gases (ammonia from manure or factory, chlorin, strong
sulphur fumes, smoke, and other products of combustion, etc.) may start
the inflammation. The eyelids often undergo extreme inflammatory and
dropsical swelling in urticaria (nettlerash, surfeit) and in the general
inflammatory dropsy known as purpura hemorrhagica.
The affection will, therefore, readily divide itself into (1)
inflammations due to constitutional causes; (2) those due to direct
injury, mechanical or chemical; and (3) such as are due to inoculation
with infecting material.
(1) Inflammations due to constitutional causes are distinguished by the
absence of any local wound, and the history of a low, damp pasture,
exposure, indigestion from unwholesome feed, or the presence elsewhere
on the limbs or body of the general, doughy swellings of purpura
hemorrhagica. The lids are swollen and thickened; it may be slightly or
it may be so extremely that the eyeball can not be seen. If the lid can
be everted to show its mucous membrane, that is seen to be of a deep-red
color, especially along the branching lines of the blood vessels. The
part is hot and painful, and a profuse flow of tears and mucus escapes
on the side of the face, causing irritation and loss of the hair. If
improvement follows, this discharge becomes more tenacious, and tends to
cause adhesion to the edges of the upper and lower lids and to mat
together the eyelashes in bundles. This gradually decreases to the
natural amount, and the redness and congested appearance of the eye
disappears, but swelling, thickening, and stiffness of the lids may
continue for a time. There may be more or less fever according to the
violence of the inflammation, but so long as there is no serious disease
of the interior of the eye or of other vital organ, it is usually
moderate.
The local treatment consists in astringent, soothing lotions (sugar of
lead 30 grains, laudanum 2 teaspoonfuls, rain water--boiled and
cooled--1 pint), applied with a soft cloth kept wet with the lotion, and
hung over the eye by tying it to the headstall of the bridle on the two
sides. If the mucous membrane lining of the lids is the seat of little
red granular elevations, a drop of solution of 2 grains of nitrate of
silver in an ounce of distilled water should be applied with the soft
end of a clean feather to the inside of the lid twice a day. The patient
should be removed from all such conditions (pasture, faulty feed,
exposure, etc.) as may have caused or aggravated the disease, and from
dust and irritant fumes and gases. He should be fed from a manger high
enough to favor the return of blood from the head, and should be kept
from work, especially in a tight collar which would prevent the descent
of blood by the jugular veins. The diet should be laxative and
nonstimulating (grass, bran mashes, carrots, turnips, beets, potatoes,
or steamed hay), and any costiveness should be corrected by a mild dose
of raw linseed oil (1 to 1-1/2 pints). In cold weather warm blanketing
may be needful, and even loose flannel bandages to the limbs, but heat
should never be sought at the expense of pure air.
(2) In inflammations due to local irritants of a noninfective kind a
careful examination will usually reveal their presence, and the first
step must be their removal with a pair of blunt forceps or the point of
a lead pencil. Subsequent treatment will be in the main the local
treatment advised above.
(3) In case of infective inflammation there will often be found a prick
or tear by which the septic matter has entered, and in such case the
inflammation will for a time be concentrated at that point. A round or
conical swelling around an insect bite is especially characteristic. A
snake bite is marked by the double prick made by the two teeth and by
the violent and rapidly spreading inflammation. Erysipelas is attended
with much swelling, extending beyond the lids and causing the mucous
membrane to protrude beyond the edge of the eyelid (chemosis). This is
characterized by a bright, uniform, rosy red, disappearing on pressure,
or later by a dark, livid hue, but with less branching redness than in
noninfecting inflammation and less of the dark, dusky, brownish or
yellowish tint of anthrax. Little vesicles may appear on the skin, and
pus may be found without any distinct limiting membrane, as in abscess.
It is early attended with high fever and marked general weakness and
inappetence. Anthrax of the lids is marked by a firm swelling,
surmounted by a blister, with bloody serous contents, which tends to
burst and dry up into a slough, while the surrounding parts become
involved in the same way. Or it may show as a diffuse, dropsical
swelling, with less of the hard, central sloughing nodule, but, like
that, tending to spread quickly. In both cases alike the mucous membrane
and the skin, if white, assumes a dusky-brown or yellowish-brown hue,
which is largely characteristic. This may pass into a black color by
reason of extravasation of blood. Great constitutional disturbance
appears early, with much prostration and weakness and generalized
anthrax symptoms.
_Treatment._--The treatment will vary according to the severity. Insect
bites may be touched with a solution of equal parts of glycerin and aqua
ammonia, or a 10 per cent solution of carbolic acid in water. Snake
bites may be bathed with aqua ammonia, and the same agent given in doses
of 2 teaspoonfuls in a quart of water, or alcohol may be given in pint
or quart doses, according to the size of the animal. In erysipelas the
skin may be painted with tincture of chlorid of iron, or with a solution
of 20 grains of iodin in an ounce of carbolic acid, and one-half an
ounce of tincture of chlorid of iron may be given thrice daily in a
bottle of water. In anthrax the swelling should be painted with tincture
of iodin, or of the mixture of iodin and carbolic acid, and if very
threatening it may have the tincture of iodin injected into the swelling
with a hypodermic syringe, or the hard mass may be freely incised to its
depth with a sharp lancet and the lotion applied to the exposed tissues.
Internally, iodid of potassium may be given in doses of 2 drams thrice a
day, or tincture of the chlorid of iron every four hours.
STY, OR FURUNCLE (BOIL) OF THE EYELID.
This is an inflammation of limited extent, advancing to the formation of
matter and the sloughing out of a small mass of the natural tissue of
the eyelid. It forms a firm, rounded swelling, usually near the margin
of the lid, which suppurates and bursts in four or five days. Its course
may be hastened by a poultice of camomile flowers, to which have been
added a few drops of carbolic acid, the whole applied in a very thin
muslin bag. If the swelling is slow to open after having become
yellowish white, it may be opened by a lancet, the incision being made
at right angles to the margin of the lid.
ENTROPION AND ECTROPION, OR INVERSION AND EVERSION OF THE EYELID.
These are respectively caused by wounds, sloughs, ulcers, or other
causes of loss of substance of the mucous membrane on the inside of the
lid and of the skin on the outside; also of tumors, skin diseases, or
paralysis which leads to displacement of the margin of the eyelid. As a
rule, they require a surgical operation, with removal of an elliptical
portion of the mucous membrane or skin, as the case may be, but which
requires the skilled and delicate hand of the surgeon.
TRICHIASIS.
This consists in the turning in of the eyelashes so as to irritate the
front of the eye. If a single eyelash, it may be snipped off with
scissors close to the margin of the eyelid or pulled out by the root
with a pair of flat-bladed forceps. If the divergent lashes are more
numerous, the treatment may be as for entropion, by excising an
elliptical portion of skin opposite the offending lashes and stitching
the edges together, so as to draw outward the margin of the lid at that
point.
WARTS AND OTHER TUMORS OF THE EYELIDS.
The eyelids form a favorite site for tumors, and above all, warts, which
consist in a simple diseased overgrowth (hypertrophy) of the surface
layers of the skin. If small, they may be snipped off with scissors or
tied around the neck with a stout, waxed thread and left to drop off,
the destruction being completed, if necessary, by the daily application
of a piece of sulphate of copper (blue vitriol), until any unhealthy
material has been removed. If more widely spread, the wart may still be
clipped off with curved scissors or knife, and the caustic thoroughly
applied day by day.
A bleeding wart, or erectile tumor, is more liable to bleed, and is best
removed by constricting its neck with the waxed cord or rubber band, or
if too broad it may be transfixed through its base by a needle armed
with a double thread, which is then to be cut in two and tied around the
two portions of the neck of the tumor. If still broader, the armed
needle may be carried through the base of the tumor at regular
intervals, so that the whole may be tied in moderately sized sections.
In gray and in white horses black, pigmentary tumors (melanotic) are
common on the black portions of skin, such as the eyelids, and are to be
removed by scissors or knife, according to their size. In the horse they
do not usually tend to recur when thoroughly removed, but at times they
prove cancerous (as is the rule in man), and then they tend to reappear
in the same site or in internal organs with, it may be, fatal effect.
Encysted, honeylike (melicerous), sebaceous, and fibrous tumors of the
lids all require removal with the knife.
TORN EYELIDS OR WOUNDS OF EYELIDS.
The eyelids are torn by attacks with horns of cattle, or with the teeth,
or by getting caught on nails in stall, rack, or manger, on the point of
stumps, fences, or fence rails, on the barbs of wire fences, and on
other pointed bodies. The edges should be brought together as promptly
as possible, so as to effect union without the formation of matter,
puckering of the skin, and unsightly distortions. Great care is
necessary to bring the two edges together evenly without twisting or
puckering. The simplest mode of holding them together is by a series of
sharp pins passed through the lips of the wound at intervals of not more
than a third of an inch, and held together by a thread twisted around
each pin in the form of the figure 8, and carried obliquely from pin to
pin in two directions, so as to prevent gaping of the wound in the
intervals. The points of the pins may then be cut off with scissors, and
the wound may be wet twice a day with a weak solution of carbolic acid.
TUMOR OF THE HAW, OR CARIES OF THE CARTILAGE.
Though cruelly excised for alleged "hooks," when itself perfectly
healthy, in the various diseases which lead to retraction of the eye
into its socket, the haw may, like other bodily structures, be itself
the seat of actual disease. The pigmentary, black tumors of white horses
and soft (encephaloid) cancer may attack this part primarily or extend
to it from the eyeball or eyelids; hairs have been found growing from
its surface, and the mucous membrane covering it becomes inflamed in
common with that covering the front of the eye. These inflammations are
but a phase of the inflammation of the external structures of the eye,
and demand no particular notice nor special treatment. The tumors lead
to such irregular enlargement and distortion of the haw that the
condition is not to be confounded with the simple projection of the
healthy structure over the eye when the lids are pushed apart with the
finger and thumb, and the same remark applies to the ulceration, or
caries, of the cartilage. In the latter case, besides the swelling and
distortion of the haw, there is this peculiarity, that in the midst of
the red inflamed mass there appears a white line or mass formed by the
exposed edge of the ulcerating cartilage. The animal having been thrown
and properly fixed, an assistant holds the eyelids apart while the
operator seizes the haw with forceps or hook and carefully dissects it
out with blunt-pointed scissors. The eye is then covered with a cloth,
kept wet with an eyewash, as for external ophthalmia.
OBSTRUCTION OF THE LACRIMAL APPARATUS, OR WATERING EYE.
The escape of tears on the side of the cheek is a symptom of external
inflammation of the eye, but it may also occur from any disease of the
lacrimal apparatus which interferes with the normal progress of the
tears to the nose; hence, in all cases when this symptom is not attended
with special redness or swelling of the eyelids, it is well to examine
the lacrimal apparatus. In some instances the orifice of the lacrimal
duct on the floor of the nasal chamber and close to its anterior outlet
will be found blocked by a portion of dry mucopurulent matter, on the
removal of which tears may begin to escape. This implies an inflammation
of the canal, which may be helped by occasional sponging out of the nose
with warm water, and the application of the same on the face. Another
remedy is to feed warm mashes of wheat bran from a nosebag, so that the
relaxing effects of the water vapor may be secured.
The two lacrimal openings, situated at the inner angle of the eye, may
fail to admit the tears by reason of their deviation outward in
connection with the eversion of the lower lid or by reason of their
constriction in inflammation of the mucous membrane. The lacrimal sac,
into which the lacrimal ducts open, may fail to discharge its contents
by reason of constriction or closure of the duct leading to the nose,
and it then forms a rounded swelling beneath the inner angle of the eye.
The duct leading from the sac to the nose may be compressed or
obliterated by fractures of the bones of the face, and in disease of
these bones (osteosarcoma, so-called osteoporosis, diseased teeth,
glanders of the nasal sinuses, abscess of the same cavities).
The narrowed or obstructed ducts may be made pervious by a fine, silver
probe passed down to the lacrimal sac, and any existing inflammation of
the passages may be counteracted by the use of steaming mashes of wheat
bran, by fomentations or wet cloths over the face, and even by the use
of astringent eyewashes and the injection of similar liquids into the
lacrimal canal from its nasal opening. The ordinary eyewash may be used
for this purpose, or it may be injected after dilution to half its
strength. The fractures and diseases of the bones and teeth must be
treated according to their special demands when, if the canal is still
left pervious, it may be again rendered useful.
EXTERNAL OPHTHALMIA, OR CONJUNCTIVITIS.
In inflammation of the outer parts of the eyeball the exposed vascular
and sensitive mucous membrane (conjunctiva) which covers the ball, the
eyelids, the haw, and the lacrimal apparatus, is usually the most deeply
involved, yet adjacent parts are more or less implicated, and when
disease is concentrated on these contiguous parts it constitutes a
phase of external opththalmia which demands a special notice. These have
accordingly been already treated of.
_Causes._--The causes of external opththalmia are mainly those that act
locally--blows with whips, clubs, and twigs, the presence of foreign
bodies, like hayseed, chaff, dust, lime, sand, snuff, pollen of plants,
flies attracted by the brilliancy of the eye, wounds of the bridle, the
migration of the scabies (mange) insect into the eye, smoke, ammonia
arising from the excretions, irritant emanations from drying marshes,
etc. Road dust containing infecting microbes is a common factor. A very
dry air is alleged to act injuriously by drying the eye as well as by
favoring the production of irritant dust; the undue exposure to bright
sunshine through a window in front of the stall, or to the reflection
from snow or water, also is undoubtedly injurious. The unprotected
exposure of the eyes to sunshine through the use of a very short
overdraw check is to be condemned, and the keeping of the horse in a
very dark stall, from which it is habitually led into the glare of full
sunlight, intensified by reflection from snow or white limestone, must
be set down among the locally acting causes. Exposure to cold and wet,
to wet and snow storms, to cold drafts and wet lairs must also be
accepted as causes of conjunctivitis, the general disorder which they
produce affecting the eye, if that happens to be the weakest and most
susceptible organ of the body, or if it has been subjected to any
special local injury, like dust, irritant gases, or excess of light.
Again, external opththalmia is a constant concomitant of inflammation of
the contiguous and continuous mucous membranes, as those of the nose and
throat--hence the red, watery eyes that attend on nasal catarrh, sore
throat, influenza, strangles, nasal glanders, and the like. In such
cases, however, the affection of the eye is subsidiary and is manifestly
overshadowed by the primary and predominating disease.