THE HUMAN EYE

Evening Star, Issue 20024, 15 November 1928, Page 11

THE HUMAN EYE

RECENT ADVANCES IK THE STUDY Much of tho recent work in that part of medical science which deals witn the investigation and treatment of the eye is as yet of academic interest only (writes “ Keratome,” in the Melbourne ‘ Age ’). Theories of the nature ot light, the emission of light, just how it acts on the eye, and even the effect of gravity on light itself, at present o not come into the scope of any but the physicist and the psysiologist. But tie discovery of some of the results or tlio action of ultra-violet light l lvm S ISsue concerns us all. It should be borne in mind that ultra-violet light is quite a different thing from the “ violet ray, which came into vogue a few years ago, and which has no practical healing effect whatever. Ultra-violet light acts like very intense sunlight, and it is therefore a form of energy which needs very careful handling. The transparent tissues of the eye all absorb the harmful elements in this light in varying degree. Ultra-violet light is readily produced by passing a current through boiling mercury, _as in the mercury vapour lamp, which is used in treatment of certain skin diseases. In applying this light to the eye another method is employed, that of the electric arc lamp. This is being tried in certain superficial eye conditions, but it is too early to speak of results. Much research has been done in London on tho development of the eye. The importance of this work is very great when considering the numerous eye defects seen at birth or known to have been present from that time. Tho applying of the principles of the microscope to tho investigation of eye diseases nas found a practical outcome in the apapratus known as the ‘ slit iamp ” and corneal microscope, and tho Gullstrand ophalmoscope- With these instruments it is possible to examine many parts of the eye under a high power ot magnification. Such examination has made it necessary to revise some of the older theories, and has made it possible to detect inflammation in an eye very much earlier than formerly. Another new method is that ot using what is called “ red free ” light—i.'e.. light without the red rays of the spectrum. This light appears to he a bluish-green colour, and the interior of the eye shows itself as quite a different picture from that seen when white light is used. Tho dreaded disease glaucoma, ot which the causes are lor the most part unknown, is ever with us, but tho methods of investigating its beginnings are being made more accurate. Tho more obscure cases may advance almost to blindness before the patient is awaro of its presence. Those warning signs, the rainbows seen round lights, and the slow contraction of tho field of vision, may pass almost unnoticed at first, or they may bo absent altogether. A careful overhaul of the eyes in middle life is a sound procedure, for then a careful oculist will often detect other danger signs, and take the appropriate measures. Tho becoming opaque ot tho crystalline lens of the eye, or cataract, as it is called; is another condition which may begin about tho same period, and this degeneration can often bo checked by correcting some medical condition, but as yet no scientific evidence has been brought forward to prove that any method ot local treatment is able to “ dissolve ” cataract. However, with improved operating metuuds, particularly in regard to tho prevention of infection and better technique, it is now safe to remove cataracts much earlier than formerly.

With tho great public interest in blood pressure, which is not a disease of itself but only a sign of some other defect, it is of interest to remember that it is very often the occulist who first sees tho signs in the eye, and is then able to advise the patient to seek further advice before the underlying condition advances too iar. Tho same applies to early kidney disease, and in some measure to diabetes. Such cooperation between oculist and physician is one of the functions of preventive medicine in its widest sense.

With regard to squint or “ cross eye” in children, the day is not jot when even all medical men realise the importance of early ■ treatment, and here in the case of a little child the parents suffer from a multitude of advisers. and too often the result is the seeking of an occulist’s advice is delaved till the child is nine or ten years old. it cannot be too strongly emphasised that squinting children mast be attended to between the ages of uvo and sis, or seven, if the sight in each eye is to be preserved. After seven years the sight in one eye may oo found to bo sadly below normal, and to be incapable of being unproved. Opinions expressed so freely and so unwisely in such form as “ what a shame to put a little.child into glasses,” are luito at variance ith facts known about squint, though here the whole story is by no means yet pierced, together; but it is well established that what is known as sterioscopic vision is practically never acquired after seven years, of age, ft has been weil said that modern conditions of industry demand good vision, and this is what every child is entitled to. The art of spectacle making has advanced, and at last the prejudice against largo circular lenses has died, while the craze for pinco-nez glasses is passing. But it is in the actual glass making where advances of another type have taken place. The perfection of a glass which will filter out the harmful ultra violet rays and yet allow enough light to pass through without giving the wearer a sensation of looking through smoke was accomplished by that great English scientist. Sir William Crookes. Ho has had many imitators, but few have equalled his achievement, and now the 'glass makers are trying to make a glass which will allow all the beneficial ravs in sunlight to pass through. The otten-repeatea remark that glasses are worn much more than in one’s younger days is not a fact to be deplored, but a matter of rejoicing, for oy the aid of glasses a very largo proportion of defective eves are made as efficient as the normal eyes of the more fortunate, and so give a more equal chance in all walks of life. the fitter and turner and those similarly employed still seem to be quite regardless of the enormous risks they run trora injury by Hying particles of metal, and it is difficult to gam acceptance or the doa of protecting the eyes with goggles at such work—tlle Australian seems to scorn such measures as

being namby-pamby, as he does the using of leather gloves at rough work and dirty work. In tho United States the reverse holds, and no man will handle metal without gloves, nor work a lithe "or emery wheel without goggles. So great is tho demand; for goggles that at least two huge manufacturing houses make nothing else but protective goggles for all purposes. It is to be hoped that before long pur workers will demand similar protection; in fact, no sensible employer would refuse it were bo asked, for he is anxious to have his operatives at full efficiency, and surely the most thoughtless in the community would not wish to nave a damaged eye. The development of the workshop conscience in regard to self-protection_ is a matter of time, and only by repeating such warnings as these can such a state of affairs come about. A very pertinent question wnich may demand instant action by anyone is, What is tho best way to act in the case ot eye injury Y With regard to flying particles of dust, cinders, emery spaiks, and the liko, tho involuntary closing of the lids gives the clue —keep the lids closed till assistance is at hand. Probably the best and safest way to remove such foreign matter is to employ a little mop made of cotton wool wrapped firmly round the end of a match, and then dipped in clean water. Lime, cement, plaster, and such substances are better flushed out of an eye by cil or liquid paraffin, and not by water, as the latter will cause further slacking of tho lime and consequently further injury; in case of difficulty no time should bo lost in seeking export advice and treatment. There are fortunately few cases of penetration of an eye by external agents such as sticks, stones, scissor blades, bursting of bottles, and so on, and the first aid should be confined to the application of a clean dressing. Further interference must be left to others, at whose hands prompt measures may save the sufferer from the necessity of resorting to that triumph of the glass worker’s art, the artificial eye!