Eye Care Blog

Secondly, such rays (peripheral vision) may be scattered by such scarring and cause unusual sensitivity to bright light. The cuts may also damage the very sensitive deeper layers of the cornea creating problems in later life, although the operation is too new to know whether and to what extent this is the case. The effects of cuts cannot easily be measured, while the ability of the tissue to heal totally may prejudice even the short-term benefits. The presence of a small degree of short sight may seem a great inconvenience to a young person, and he or she is often willing to take a long-term risk for the sake of an immediate improvement. However, it is well to remember that a small degree of short sight when you are young can be a great blessing when you are older, because with age the eye naturally tends towards long sight; so that if you insist on an operation when you are young you may well miss out on being able to read without the aid of spectacles when you are fifty. Ifyou are mildly short-sighted you should decide which you want, normal sight in youth or normal near sight in middle and old age. Given the average life span of seventy years, the average age of first myopic development at ten years, and the onset of near-vision problems at forty, it is a question of the first thirty years against the last thirty. In making the choice, the agility of youth as opposed to the relative immobility of age must be taken into consideration, whether it gives greater pleasure and happiness to have normal vision during adolescence and young adulthood, or good vision later on in life. Each age group tends to make its own different assessment, and even the age of the qualified adviser may have to be regarded as a factor in the decision whether or not to operate. Senior practitioners will tend to advise against surgery, and thus does the tyranny of age triumph over the tyranny of youth.

There are other surgical techniques for flattening the curve of the cornea, all involving removal of tissue, but all more serious in their complications than Radial Keratotomy. They are used only in correcting more substantial degrees of myopia, say from six to sixteen dioptres.

However, the cornea may be artificially flattened without recourse to surgery by using small, hard contact lenses. Unlike ordinary contact lenses they are purposely designed to bring sustained pressure on the cornea; but at best they can only correct up to two dioptres of vision, and in many cases the correction is only temporary, so that after a while it again becomes necessary to wear the lenses. There is also the risk of creating irregular curves on the cornea, which will cause visual distortions.

Other mechanical techniques of flattening the cornea have been attempted. Various ways of relaxing the outside eye muscles (which help to make the eyes `bulge’), including acupuncture and electrolysis, have had their advocates, though the results have been far from conclusive. There also exist techniques that combine the mechanical with the psychological. Of these the ‘Bates Method’ is the best known. Certainly it is the one for which the most exaggerated claims have been made.

William H. Bates was a New York ophthalmologist who practised at the beginning of this century. The title of his famous book speaks for itself: Better Eyesight without Glasses. In it he recommends the treatment of short-sightedness by non-medical and non-optical methods. (Glasses, wrote one of his disciples, are to be regarded as ‘eye crutches’.) Aldous Huxley, who was almost blind, is reputed to have gained relief by doing the exercises that Bates advises. The very short-sighted, Bates suggests, should be taught to make the best use of object outlines as a method of recognition. For those with a smaller degree of short-sightedness various eye relaxation and eye-muscle exercises are recommended, along with ‘palming’ (a way of applying pressure to the eyes using the hands), and ’swinging’, a callisthenic exercise that massages the eyeballs by rhythmically alternating the body’s centre of gravity. While, individually, none of these practices is likely to cause harm, and may even help (`palming’ certainly helps, if only because it means the patient is unlikely to read too excessively), in their collective presentation they amount to an attempt to make the patient think his way out of trouble. Other similar programmes involve homoeopathic medicine, stimulation to the neck muscles, even hypnosis. Together they constitute a field of practice where the suggestive personality is most likely to find help. None of the techniques is scientifically proven, but they gain adherents among sufferers who have failed to find succour from orthodox practitioners. However, although a mildly short-sighted person will almost certainly improve his or her sight without recourse to glasses or spectacles by learning how to relax the eyes and avoid all close work, little succour is offered to the busy city executive or eager student.

So much, then, for the cornea. We come briefly to the crystalline lens. It has been stated that if the inner lens could be made to flatten its curves, this too would reduce the total eye power and therefore bring the image back into place on the retina. Very simply, this can be done by looking in the distance and avoiding all close work. Not realizing the mechanics of this, it is surprising how often a patient will tell his doctor that he has been seeing better during a trip to the mountains. Eye-drops containing drugs which act upon the eye’s internal muscles of accommodation (the ciliary muscle), thus releasing tension in the ligaments that keep the crystal lens in position, can be very effective. But such drugs dilate the pupil and cause excessive sensitivity to light, and so are only useful when short sight is sudden in onset and related to a spasm induced by near-sight tasks. It is not possible to move the inner lens forwards or backwards by mechanical (surgical) means. The crystal lens can be removed, and this will correct very high powers of short sight (say —18 dioptres), but such removal is a procedure that is liable to weaken the eye in other ways.

The mechanical methods of correcting short sight are still limited, therefore, and it is still the case that, in nearly every instance, the preferred solution is to use optical aids, i.e. spectacles and contact lenses.

Possibly related posts: (automatically generated)
Short-sightedness and the Environment part 3

• Short-sightedness and the Environment part 1
• Your Eyes and their Care, the Media of the Eye, and Glaucoma part 2
• Short-sightedness and the Environment part 2
• Uncomfortable Eye, Computers and Eyestrain
• Eyeglasses / Spectacle Wearers, Eye Make-up Tips
• Eye Sight, Short- and Long-Sightedness
• Eye-Strain, might need Vision Test
• Eye Sight, Short- and Long-Sightedness continued
• The Appearance of Contact Lenses part 1
• Exercising Eye Visual Memory and Vivid Imagination