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• TWITCHING OF THE EYELIDS
• CONGESTION OF THE EYELIDS
• Sympathetic Headaches

One eye is commonly attacked twenty four to thirty six hours before the other, and even if it is thought that the cause is a cinder, in case of one eye, it can hardly be possible to sustain this belief in the case of the involvement of both eyes. There is a feeling of discomfort about the eyes, and often a burning, and constant watering, the tears containing flakes of white discharge.

When the discharge is a copious, creamy pus or “matter,” associated with great swelling of the lids and pain on exposure to light, the cause is usually a germ of a special disease, and the eyesight will very probably be lost unless a skillful physician be immediately secured. Early treatment is, however, of great service, and, until a physician can be obtained, the treatment recommended below should be followed conscientiously; by this means the sight may be saved. This dangerous variety of inflammation of the eyes is not rare in the newborn, and infants having red eyes within a few days of birth should immediately receive proper attention, or blindness for life will be the issue. This is the usual source of that form of blindness with which babies are commonly said to have been born.

All forms of severe inflammation of the lids are contagious, especially the variety last considered, and can be conveyed, by means of the discharge, through the agency of towels, handkerchiefs, soap, wash basins, etc., and produce the same or sometimes different types of inflammation in healthy eyes. Therefore, if the severe form of conjunctivitis breaks out among any large number of people, as in schools, prisons, asylums, and almshouses, isolation of the patients should be enforced.

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• SORE EYES; CONJUNCTIVITIS
• PINK EYE
• TWITCHING OF THE EYELIDS

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Symptoms. The eyes feel weary and “as if there were sand in them.” There may be also smarting, burning, or itching of the lids, and there is disinclination for any prolonged use of the eyes. The lids, when examined, are found to be much deeper red than usual, and slightly swollen, but there is no discharge from the eye, and this fact serves to distinguish this mild type of inflammation from the more severe form.

Treatment. The use of dark glasses and a few drops of zinc sulphate solution (one grain to the ounce of water) in the eye, three times daily, will often cure the trouble. If this does not do so within a few days then an oculist should be consulted, and it will frequently be found that glasses are needed to secure freedom from irritation of the eyes. In using “eye drops” the head should be held back, and several drops be squeezed from a medicine dropper into the inner corner of the eye.

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• SORE EYES; CONJUNCTIVITIS
• Constant Headache
• PINK EYE

In order that vision be clear and perfect, it is essential that the rays of light entering the eye be bent so that they strike the retina as a single point. In the farsighted or hyperopic eye, the eyeball is usually too short for the rays to be properly focused on the sensitive nerve area in the back of the eye.

This defect in vision is, however, overcome by the act of “accommodation.” There is a beautiful transparent, double convex body, about one third of an inch thick, which looks very much like an ordinary glass lens, and is situated in the eye just back of the pupil. This is what is known as the crystalline lens, and the rays of light are bent in passing through it so as to be properly focused on the retina.

The foregoing statements have been made as though objects were always at a distance from the eye, so that the rays of light coming from them were almost parallel. Yet when one is looking at an object within a few inches of the eye the rays diverge or spread out, and these the normal eye (if rigid) could not focus on the retina much less the farsighted eye. But the eye is adaptable to change of focus through the action of a certain muscle, situated within the eyeball about the lens, which controls to a considerable extent the shape of the lens. When the muscle contracts it allows the lens to bulge forward by virtue of its elasticity, and, therefore, become more convex. This is what happens when one looks at near objects, the increased convexity of the lens bending the rays of light so that they will focus as a point on the retina.

Now in the farsighted eye this muscular control or “accommodative action” must be continually exercised even in looking at distant objects, and it is this constant attempt of nature to cure an optical defect of the eye which frequently leads to nervous exhaustion or eye strain. The nerve centers, which animate and control the nerves supplying the eye muscles to which we have just alluded, are in close proximity to other most important nerve centers in the brain, so irritation of the eye centers will produce sympathetic irritation of these other centers, leading to manifold and complex symptoms which we will describe under this head. But these symptoms do not necessarily develop in everyone having farsightedness or astigmatism, since both are often present at birth.

The power of accommodation is sufficient to overcome the optical defect of the eye, providing that the general health is good and the eye is not used much for near work. If, on the other hand, excessive use of the eyes in reading, writing, figuring, sewing, or other fine work is required, and especially if the health becomes impaired, it happens that the constant drain on the eye center in the brain will result in a group of symptoms which we will consider later. Failure of accommodation comes on at about forty, and gradually increases until all accommodation is lost at the age of seventy five.

For this reason it is necessary for persons over forty five years of age, having normal or farsighted eyes, to wear convex glasses in reading or doing near work, and these should be changed for stronger ones every year or two. These convex glasses save the eyes in their attempt to make the lens more convex when looking at near objects in farsightedness, and also prove serviceable in the same manner when accommodation begins to fail in the case of what is called “old sight.” The neglect to provide proper glasses for reading any time after the age of forty five, and the failure to replace them by stronger lenses when required, distinctly favor the occurrence of cataract in later life.

In the act of accommodation, in addition to the muscular action by which the lens is made more convex, there is the tendency for the action of another group of muscles outside the eyeball, which turn the eyes inward when they are directed toward a near object. Here then is another source of trouble resulting from farsightedness, i. e., the not infrequent occurrence of inward “squint” occasioned by the constant use of the muscles pulling the eyes inward during accommodation for near objects. Again, inflammation of the eyelids, and sometimes of deeper parts of the eyeball, follows untreated hyperopia. Early distaste for reading is often acquired by farsighted persons, owing to the strain on the accommodative apparatus. The convex lens is that used to correct farsightedness.

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• Symptoms of Eye strain
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Eye strain in this optical defect is brought on by constant use of the eye muscles (attached to the outside of the eyeball) in directing both eyes inward so that they will both center on near objects; the only ones which can be seen. Outward squint frequently results, because the muscular efforts required to direct both eyes equally inward to see near objects are so great that the use of both eyes together is given up, and the poorer eye is not used and squints outward, while the better eye is turned inward in the endeavor to see. Nearsighted persons are apt to stoop, owing to the habitual necessity for coming close to the object looked at. Their facial expression is also likely to be rather vacant, since they do not distinctly see, and do not respond to the facial movements of others.

Nearsightedness, or myopia, is not a congenital defect, but is usually acquired owing to excessive near work which requires that the eye muscles constantly direct both eyes inward to see near objects. In so acting the muscles compress the sides of the eyeballs and tend to increase their length, interfere with their nutrition, and aggravate the condition when it is once begun. Concave lenses are used to correct myopia, and they must be worn all the time.

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• ASTIGMATISM

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The immediate treatment, which may cut short the trouble, consists in bathing the eyelid for fifteen minutes at a time, every hour, with a hot solution of boric acid (half a teaspoonful to the cup of water). Then at night the swelling should be painted with collodion, several coats, being careful not to get it in the eye, as it would cause much smarting. If the stye persists in progressing, bathing it in hot water will cause it to discharge pus and terminate much sooner.

Treatment. In the milder attacks of conjunctivitis the treatment should be that recommended above for congestion of the lids. The swelling and inflammation, in the severer types, are greatly relieved by the application of the cold water compresses, advised under the section on “black eye,” for an hour at a time, thrice daily. Confinement in a dark room, or the use of dark glasses, and drops of zinc sulphate (one grain in an ounce of water) three times a day, with hourly dropping of boric acid (ten grains to the ounce of water) constitute the ordinary treatment.

In inflammations with copious discharge of creamy pus, and great swelling of the lids, the eyes should be washed out with the boric acid solution every half hour, and a solution of silver nitrate (two grains to the ounce of water) dropped into the eye, once daily, followed immediately by a weak solution of common salt in water to neutralize the nitrate of silver, after its action has been secured. The constant use of ice cloths, already mentioned, forms a necessary adjunct to treatment. The sound eye must be protected from the chance of contagion, arising from a possible infection from the pus discharging from its mate. This may be secured by bandaging the well eye, or, better, by covering it with a watch crystal kept in place by surgeon’s plaster.

In treating sore eyes with discharge, in babies, the infant should be held in the lap with its head backward and inclined toward the side of the sore eye, so that in washing the eye no discharge will flow into the sound eye. The boric acid may then be dropped from a medicine dropper, or applied upon a little wad of absorbent cotton, to the inner corner of the eye, while the eyelids are held apart.

Hemorrhages occurring under the conjunctiva (or membrane lining the inner surface of the lids and covering the front surface of the eyeball) may be caused by blows or other injury to the eye, by violent coughing, by straining, etc. Dark red spots may appear in the white of the eyeball, slightly raised above the surface, which are little blood clots under the conjunctival membrane. No special trouble results and there is nothing to be done except to wait till the blood is absorbed, which will happen in time. If the eyes water, solution of zinc sulphate (one grain to the ounce of water) may be dropped into the eye, twice daily. Hot applications are beneficial here to promote absorption of the clot.

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• WARTS

Rays of light in passing through the different meridians of the astigmatic eye are differently bent, so that in one of the principal meridians rays may focus perfectly on the retina, while in the other the rays may focus on a point behind the retinal field. In this case the eye is made farsighted or hyperopic in one meridian, and is normal in the other. Or again, the rays may be focused in front of the retina in one meridian, and directly on the retina in the other; this would be an example of nearsighted or myopic astigmatism. Farsightedness and nearsightedness are then both caused by astigmatism, although in this case not by the length of the eyeball, but by inequality in the curvature of the front part (cornea) of the eyeball. For example, in simple astigmatism one of the principal meridians is hyperopic (turning the rays so that they focus behind the retina) or myopic (bending the rays so that they focus in front of the retina), while the other meridian is normal. In mixed astigmatism, one of the principal meridians is myopic, the other hyperopic; in compound astigmatism the principal meridians are both myopic, or both hyperopic, but differ in degree; while in irregular astigmatism, rays of light passing through different parts of the outer surface of the eyeball are turned in so many various directions that they can never be brought to a perfect focus by glasses.

It is not by any means possible for a layman to be able always to inform himself that he is astigmatic, unless the defect is considerable. If a card, on which are heavy black lines of equal size and radiating from a common center like the spokes of a wheel, be placed on a wall in good light, it will appear to the astigmatic eye as if certain lines (which are in the faulty meridian of the eyeball) are much blurred, while the lines at right angles to these are clear and distinct. Each eye should be tested separately, the other being closed. The chart should be viewed from a distance as great as any part of it can be seen distinctly. All the lines on the test card should look equally black and clear to the normal eye.

Astigmatism is corrected by a cylindrical lens, which is in fact a segment of a solid cylinder of glass. The axis of the cylindrical lens should be at right angles to the defective meridian of the eye, in order to correct the astigmatism. Eye strain is caused by astigmatism in the same manner that it is brought about in the simple farsighted eye, i. e., by constant strain on the ciliary muscle, which regulates the convexity of the crystalline lens. For it is possible for the inequalities of the front surface of the eyeball or of the lens to be offset or counterbalanced by change in the convexity of the lens produced by the action of this muscle, and it is conceivable that the axis of the lens may be tilted one way or another by the same agency, and for the same purpose. But, as we have already pointed out, this continual muscular action entails great strain on the nerve centers which animate the muscle, and if constant near work is requisite, or the health is impaired, the nervous exhaustion becomes apparent. The lesser degrees of astigmatism often give more trouble than the greater.

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• CONGESTION OF THE EYELIDS
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