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."1There are also people who regain their near vision after having lost it for ten,fifteen, or more years; and there are people who, while presbyopic for someobjects, have perfect sight for others.Many dressmakers, for instance, canthread a needle with the naked eye, and with the retinoscope it can bedemonstrated that they accurately focus their eyes upon such objects; and yetthey cannot read or write without glasses.So far as I am aware no one but myself has ever observed the last-mentionedclass of cases, but the others are known to every ophthalmologist of anyexperience.One hears of them at the meetings of ophthalmological societies;they are even reported in the medical journals; but such is the force of authoritythat when it comes to writing books they are either ignored or explained away,and every new treatise that comes from the press repeats the old superstitionthat presbyopia is "a normal result of growing old." We have beaten Germany;but the dead hand of German science still oppresses our intellects and preventsus from crediting the plainest evidence of our senses.Some of us are so filledwith repugnance for1Everyman's Library, 1908, pp.166-167. 214 Presbyopia: Its Cause And Curethe Hun that we can no longer endure the music of Bach, or the language ofGoethe and Schiller; but German ophthalmology is still sacred, and no facts areallowed to cast discredit upon it.Fortunately for those who feel called upon to defend the old theories, myopiapostpones the advent of presbyopia.and a decrease in the size of the pupil,which often takes place in old age, has some effect in facilitating vision at thenear-point.Reported cases of persons reading without glasses when over fifty orfifty-five years of age, therefore, can be easily disposed of by assuming that thesubjects must be myopic, or that their pupils are unusually small.If the casecomes under actual observation, the matter may not be so simple, because itmay be found that the patient, so far from being myopic, is hypermetropic, oremmetropic, and that the pupil is of normal size.There is nothing to da with thesecases but to ignore them.Abnormal changes in the form of the lens have alsobeen held responsible for the retention of near vision beyond the prescribed age,or for its restoration after it has been lost, the swelling of the lens in incipientcataract affording a very convenient and plausible explanation for the latter classof cases.In cases of premature presbyopia "accelerated sclerosis" 1 Of the lensand weakness of the ciliary muscle have been assumed; and if such cases asthe dressmakers who can thread their needles when they can no longer read thenewspapers had been observed, no doubt some explanation consistent with theGerman viewpoint would have been found for them.The truth about presbyopia is that it is not "a normal result of growing old,"being both preventable and cuI Fuchs: Text-book of Ophthalmology, p.S05. A Form Of Hypermetropia 215rable.It is not caused by hardening of the lens, but by a strain to see at the near-point.It has no necessary connection with age, since it occurs, in some cases, asearly as ten years, while in others it never occurs at all, although the subject maylive far into the so-called presbyopic age.It is true that the lens does harden withadvancing years, just as the bones harden and the structure of the skin changes;but since the lens is not a factor in accommodation, this fact is immaterial, andwhile in some cases the lens may become flatter, or lose some of its refractivepower with advancing years, it has been observed to remain perfectly clear andunchanged in shape up to the age of ninety.Since the ciliary muscle is also not afactor in accommodation, its weakness or atrophy can contribute nothing to thedecline of accommodative power.Presbyopia is, in fact, simply a form ofhypermetropia in which the vision for the near-point is chiefly affected, althoughthe vision for the distance, contrary to what is generally believed, is alwayslowered also.The difference between the two conditions is not always clear.Aperson with hypermetropia may or may not read fine print, and a person at thepresbyopic age may read it without apparent inconvenience and yet haveimperfect sight for the distance.In both conditions the sight at both points islowered, although the patient may not be aware of it.It has been shown that when the eyes strain to see at the near-point the focusis always pushed farther away than it was before, in one or all meridians; and bymeans of simultaneous retinoscopy it can always be demonstrated that when aperson with presbyopia tries to read fine print and fails, the focus is alwayspushed farther away than it was before the attempt was made, indicat 216 Presbyopia: Its Cause And Cureing that the failure was caused by strain.Even the thought of making such aneffort will produce strain, so that the refraction may be changed, and pain,discomfort and fatigue produced, before the fine print is regarded.Furthermore,when a personwith presbyopia rests the eyes by closing them, or palming, he always becomesable, for a few moments at least, to read fine print at six inches, again indicatingthat his previous failure was due, not to any fault of the eyes, but to a strain tosee.When the strain is permanently relieved the presbyopia is permanentlycured, and this has happened, not in a few cases, but in many, and at all ages,up to sixty, seventy and eighty.The first patient that I cured of presbyopia was myself.Having demonstratedby means of experiments on the eyes of animals that the lens is not a factor inaccommodation, I knew that presbyopia must be curable, and I realized that Icould not look for any very general acceptance of the revolutionary conclusions Ihad reached so long as I wore glasses myself for a condition supposed to be dueto the loss of the accommodative power of the lens.I was then suffering from themaximum degree of presbyopia [ Pobierz całość w formacie PDF ]
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."1There are also people who regain their near vision after having lost it for ten,fifteen, or more years; and there are people who, while presbyopic for someobjects, have perfect sight for others.Many dressmakers, for instance, canthread a needle with the naked eye, and with the retinoscope it can bedemonstrated that they accurately focus their eyes upon such objects; and yetthey cannot read or write without glasses.So far as I am aware no one but myself has ever observed the last-mentionedclass of cases, but the others are known to every ophthalmologist of anyexperience.One hears of them at the meetings of ophthalmological societies;they are even reported in the medical journals; but such is the force of authoritythat when it comes to writing books they are either ignored or explained away,and every new treatise that comes from the press repeats the old superstitionthat presbyopia is "a normal result of growing old." We have beaten Germany;but the dead hand of German science still oppresses our intellects and preventsus from crediting the plainest evidence of our senses.Some of us are so filledwith repugnance for1Everyman's Library, 1908, pp.166-167. 214 Presbyopia: Its Cause And Curethe Hun that we can no longer endure the music of Bach, or the language ofGoethe and Schiller; but German ophthalmology is still sacred, and no facts areallowed to cast discredit upon it.Fortunately for those who feel called upon to defend the old theories, myopiapostpones the advent of presbyopia.and a decrease in the size of the pupil,which often takes place in old age, has some effect in facilitating vision at thenear-point.Reported cases of persons reading without glasses when over fifty orfifty-five years of age, therefore, can be easily disposed of by assuming that thesubjects must be myopic, or that their pupils are unusually small.If the casecomes under actual observation, the matter may not be so simple, because itmay be found that the patient, so far from being myopic, is hypermetropic, oremmetropic, and that the pupil is of normal size.There is nothing to da with thesecases but to ignore them.Abnormal changes in the form of the lens have alsobeen held responsible for the retention of near vision beyond the prescribed age,or for its restoration after it has been lost, the swelling of the lens in incipientcataract affording a very convenient and plausible explanation for the latter classof cases.In cases of premature presbyopia "accelerated sclerosis" 1 Of the lensand weakness of the ciliary muscle have been assumed; and if such cases asthe dressmakers who can thread their needles when they can no longer read thenewspapers had been observed, no doubt some explanation consistent with theGerman viewpoint would have been found for them.The truth about presbyopia is that it is not "a normal result of growing old,"being both preventable and cuI Fuchs: Text-book of Ophthalmology, p.S05. A Form Of Hypermetropia 215rable.It is not caused by hardening of the lens, but by a strain to see at the near-point.It has no necessary connection with age, since it occurs, in some cases, asearly as ten years, while in others it never occurs at all, although the subject maylive far into the so-called presbyopic age.It is true that the lens does harden withadvancing years, just as the bones harden and the structure of the skin changes;but since the lens is not a factor in accommodation, this fact is immaterial, andwhile in some cases the lens may become flatter, or lose some of its refractivepower with advancing years, it has been observed to remain perfectly clear andunchanged in shape up to the age of ninety.Since the ciliary muscle is also not afactor in accommodation, its weakness or atrophy can contribute nothing to thedecline of accommodative power.Presbyopia is, in fact, simply a form ofhypermetropia in which the vision for the near-point is chiefly affected, althoughthe vision for the distance, contrary to what is generally believed, is alwayslowered also.The difference between the two conditions is not always clear.Aperson with hypermetropia may or may not read fine print, and a person at thepresbyopic age may read it without apparent inconvenience and yet haveimperfect sight for the distance.In both conditions the sight at both points islowered, although the patient may not be aware of it.It has been shown that when the eyes strain to see at the near-point the focusis always pushed farther away than it was before, in one or all meridians; and bymeans of simultaneous retinoscopy it can always be demonstrated that when aperson with presbyopia tries to read fine print and fails, the focus is alwayspushed farther away than it was before the attempt was made, indicat 216 Presbyopia: Its Cause And Cureing that the failure was caused by strain.Even the thought of making such aneffort will produce strain, so that the refraction may be changed, and pain,discomfort and fatigue produced, before the fine print is regarded.Furthermore,when a personwith presbyopia rests the eyes by closing them, or palming, he always becomesable, for a few moments at least, to read fine print at six inches, again indicatingthat his previous failure was due, not to any fault of the eyes, but to a strain tosee.When the strain is permanently relieved the presbyopia is permanentlycured, and this has happened, not in a few cases, but in many, and at all ages,up to sixty, seventy and eighty.The first patient that I cured of presbyopia was myself.Having demonstratedby means of experiments on the eyes of animals that the lens is not a factor inaccommodation, I knew that presbyopia must be curable, and I realized that Icould not look for any very general acceptance of the revolutionary conclusions Ihad reached so long as I wore glasses myself for a condition supposed to be dueto the loss of the accommodative power of the lens.I was then suffering from themaximum degree of presbyopia [ Pobierz całość w formacie PDF ]