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What Everyone Should Know About Eyes
322
BOOK NOTICES
Functional vascular changes, in the form of narrowing of the lumen of the retinal vessels, are the visible expression and sequels of abnormal conditions of the vascular muscles and occur either as spastic-tetanic or as tonic contractions. The author emphasizes the necessity for clear definitions. "Spasm" involves the conception of transitory change, as there is no constant spasm of smooth muscular fibers. It means muscular contraction during which mechanical work, heat, and electricity are generated, demanding a steady afflux of energy and stimulation. Very strong, or summation of weak, stimulations may elicit a tetanic condition of greater or less duration, with subsequent signs of exhaustion that appear as fluctuations of contraction and finally must lead to relaxation and return to a physiological basis. These conditions may occur on circumscribed or longer sections of the retinal vessels. Constancy of contraction of smooth muscular fibers without constant intrinsic work and consequently without symptoms of exhaustion is classed under variations of tonus, manifested by anemia and hyperemia. Functional vascular changes may frequently be the starting point of organic disorders. They are, according to the latest researches, widely subject to the influence of the nervous system. The vasculomotor centers determining vascular tonus are cerebral, spinal in the medulla oblongata and in the segments of the spinal cord, and peripheral as histologically proved between adventitia and muscularis, which, although normally interdependent, may become automatic under pathological conditions. Further discussion includes the anatomical peculiarities of the retinal vascular system, with results of the author's own investigations in some doubtful points; vascular changes in eclampsia, illustrated by eight detailed clinical histories ; in polycythemia, with case histories; in migrain, Raynaud's disease, lead poisoning and other diseases; and finally hypertony of the
retinal vessels, with thirty-five photographs of the fundus. This valuable monograph will be read ■ with great interest and benefit. C. Zimmermann. What everyone should know about eyes. By F. Park Lewis. The National Health Series, edited by the National Health Council. 70 pages. 18mo flexible fabrikoid, price thirty cents. 1928. Funk and Wagnalls Company, New York and London. The National Health Council, of which the National Society for the Prevention of Blindness is an active member, has undertaken the publication of a "National Health Series" the object of which is to provide the general public with authoritative books on health at low cost. Dr. F. Park Lewis, vice-president of the National Society for the Prevention of Blindness, has evidently undertaken this little work on the eye as a labor of love, and he displays in it all his characteristic ability to write charmingly on medical topics for the layman. The first part deals with the mechanism of sight, the second with "when the mechanism gets out of order," the third with the eye in middle life and beyond, and the fourth with eye inheritances. It seems usually impossible for the technical writer to place himself completely on the level of his lay audience in the use of words and forms of explanation, but Dr. Lewis' qualifications in this respect are almost ideal, and only occasionally does he allow himself to employ a word with regard to whose meaning most educated laymen would feel uncertainty. Quite naturally, in a work of this kind it is necessary to state dogmatically some matters of disputed theory; for example with regard to the cause of myopia or strabismus. A useful statement is included as to the mode of testing visual acuity, and the "play" method of investigating visual acuity before the reading age,
BOOK N O T I C E S
recently popularized by the National Society for the Prevention of Blindness, is illustrated with a number of photographs. These and two facsimiles of Snellen's test cards are unfortunately the only illustrations; although a layman would surely derive much more substantial advantage from the explanations of anatomy and physiology if these were accompanied by at least a few diagrams. It would probably have avoided occasional misunderstanding if mention had been made of the fact that the test type had been reduced for reproduction in this book. In a subsequent edition correction should be made of an error on page seven, where it is stated that many of those who have better than nominally normal vision are able to read the "20-foot line at IS feet". The pocket size, excellent printing, and flexible covers of these little volumes make them very attractive for Popular reading. W. H. Crisp. Your eyes and their care. By Edgar S. Thomson. Octavo, 175 pages. Cloth bound, $1.50. D. Appleton and Company, New York and London, 1929. The general purpose of this book is similar to that of Lewis' smaller volume, mentioned above. It is more ambitious in form, and much larger, although on account of differences in printing it actually contains only about twice as much text as the smaller volume. Its mode of statement is on the whole simple and direct, although at times perhaps a trifle too formal. It gives one the impres-
323
sion of being rather in the nature of a textbook on the eye for the layman than an attempt to charm and interest him in the subject. It has the advantage of containing a few anatomical drawings and some diagrams to illustrate the processes of refraction. As stated in the preface, practical probkms have been stressed, and the question which the author has kept before him is "What information will be of advantage to the individual to enable him to cooperate understandi n g ^ in case of need?" The volume might very well serve as a textbook for nurses, except that it has not a sufficient abundance of illustrations. It is divided into the following chapters: 1, anatomy and physiology; 2, the developmental period; 3, adult life; 4, advanced age; 5, injuries. The book, which is one of a seemingly excellent series from the same publisher on a great variety of health subjects, should serve a very useful purpose among those who take the pains to acquire information concerning the bodies and senses of themselves or of their families, or it may be of those who are institutionally or industrially under their care. W. H. Crisp. Selbstheilung hoffnungsloser Krankheiten (Spontaneous cure of hopeless diseases). Dr. Carl Hamburger, Berlin. 41 pages with 4 curves in the text. Paper covers, price 2.50 marks. Jena, Verlag von Gustav Fischer. 1928. (See editorial, page 319 of this issue.)
BOOK NOTICES
Functional vascular changes, in the form of narrowing of the lumen of the retinal vessels, are the visible expression and sequels of abnormal conditions of the vascular muscles and occur either as spastic-tetanic or as tonic contractions. The author emphasizes the necessity for clear definitions. "Spasm" involves the conception of transitory change, as there is no constant spasm of smooth muscular fibers. It means muscular contraction during which mechanical work, heat, and electricity are generated, demanding a steady afflux of energy and stimulation. Very strong, or summation of weak, stimulations may elicit a tetanic condition of greater or less duration, with subsequent signs of exhaustion that appear as fluctuations of contraction and finally must lead to relaxation and return to a physiological basis. These conditions may occur on circumscribed or longer sections of the retinal vessels. Constancy of contraction of smooth muscular fibers without constant intrinsic work and consequently without symptoms of exhaustion is classed under variations of tonus, manifested by anemia and hyperemia. Functional vascular changes may frequently be the starting point of organic disorders. They are, according to the latest researches, widely subject to the influence of the nervous system. The vasculomotor centers determining vascular tonus are cerebral, spinal in the medulla oblongata and in the segments of the spinal cord, and peripheral as histologically proved between adventitia and muscularis, which, although normally interdependent, may become automatic under pathological conditions. Further discussion includes the anatomical peculiarities of the retinal vascular system, with results of the author's own investigations in some doubtful points; vascular changes in eclampsia, illustrated by eight detailed clinical histories ; in polycythemia, with case histories; in migrain, Raynaud's disease, lead poisoning and other diseases; and finally hypertony of the
retinal vessels, with thirty-five photographs of the fundus. This valuable monograph will be read ■ with great interest and benefit. C. Zimmermann. What everyone should know about eyes. By F. Park Lewis. The National Health Series, edited by the National Health Council. 70 pages. 18mo flexible fabrikoid, price thirty cents. 1928. Funk and Wagnalls Company, New York and London. The National Health Council, of which the National Society for the Prevention of Blindness is an active member, has undertaken the publication of a "National Health Series" the object of which is to provide the general public with authoritative books on health at low cost. Dr. F. Park Lewis, vice-president of the National Society for the Prevention of Blindness, has evidently undertaken this little work on the eye as a labor of love, and he displays in it all his characteristic ability to write charmingly on medical topics for the layman. The first part deals with the mechanism of sight, the second with "when the mechanism gets out of order," the third with the eye in middle life and beyond, and the fourth with eye inheritances. It seems usually impossible for the technical writer to place himself completely on the level of his lay audience in the use of words and forms of explanation, but Dr. Lewis' qualifications in this respect are almost ideal, and only occasionally does he allow himself to employ a word with regard to whose meaning most educated laymen would feel uncertainty. Quite naturally, in a work of this kind it is necessary to state dogmatically some matters of disputed theory; for example with regard to the cause of myopia or strabismus. A useful statement is included as to the mode of testing visual acuity, and the "play" method of investigating visual acuity before the reading age,
BOOK N O T I C E S
recently popularized by the National Society for the Prevention of Blindness, is illustrated with a number of photographs. These and two facsimiles of Snellen's test cards are unfortunately the only illustrations; although a layman would surely derive much more substantial advantage from the explanations of anatomy and physiology if these were accompanied by at least a few diagrams. It would probably have avoided occasional misunderstanding if mention had been made of the fact that the test type had been reduced for reproduction in this book. In a subsequent edition correction should be made of an error on page seven, where it is stated that many of those who have better than nominally normal vision are able to read the "20-foot line at IS feet". The pocket size, excellent printing, and flexible covers of these little volumes make them very attractive for Popular reading. W. H. Crisp. Your eyes and their care. By Edgar S. Thomson. Octavo, 175 pages. Cloth bound, $1.50. D. Appleton and Company, New York and London, 1929. The general purpose of this book is similar to that of Lewis' smaller volume, mentioned above. It is more ambitious in form, and much larger, although on account of differences in printing it actually contains only about twice as much text as the smaller volume. Its mode of statement is on the whole simple and direct, although at times perhaps a trifle too formal. It gives one the impres-
323
sion of being rather in the nature of a textbook on the eye for the layman than an attempt to charm and interest him in the subject. It has the advantage of containing a few anatomical drawings and some diagrams to illustrate the processes of refraction. As stated in the preface, practical probkms have been stressed, and the question which the author has kept before him is "What information will be of advantage to the individual to enable him to cooperate understandi n g ^ in case of need?" The volume might very well serve as a textbook for nurses, except that it has not a sufficient abundance of illustrations. It is divided into the following chapters: 1, anatomy and physiology; 2, the developmental period; 3, adult life; 4, advanced age; 5, injuries. The book, which is one of a seemingly excellent series from the same publisher on a great variety of health subjects, should serve a very useful purpose among those who take the pains to acquire information concerning the bodies and senses of themselves or of their families, or it may be of those who are institutionally or industrially under their care. W. H. Crisp. Selbstheilung hoffnungsloser Krankheiten (Spontaneous cure of hopeless diseases). Dr. Carl Hamburger, Berlin. 41 pages with 4 curves in the text. Paper covers, price 2.50 marks. Jena, Verlag von Gustav Fischer. 1928. (See editorial, page 319 of this issue.)