Volume 1

A dictionary of practical surgery / [Samuel Cooper].

  • Samuel Cooper
Date:
1825
Catalogue details

Licence: Public Domain Mark

Credit: A dictionary of practical surgery / [Samuel Cooper]. Source: Wellcome Collection.

    29/1282 (page 17)
    smoke, (Beer, Lehre von den Augenkrankheiten, B. 2; p- 422-26.) o an eye affected with imperfect amaurosis; all objects frequently appear indistinct, but double. (Visus duplicatus ; Diplopia.) It is remarked by Schmucker, that, in the gutta serena, which comes on gradually, the patient sometimes sees double, with both eyes. He once cured a major of hussars, who saw the three lines of his squadron double ; and he attended another gentleman simi- larly afflicted. Such cases, he conceives, are brought on by a violent distention of the vessels of the choroides, where, he thinks, varices may easily arise, in consequence of the weak resistance of that membrane. In this manner, the filaments of the retina suffer pressure, and the. rays of light are broken. Under these circumstances, if prompt assistance be not afforded, total and frequently incurable blindness may be the consequence. Schmucker met with an irremediable amaurosis of this kind, in a young man, twenty-six years of age. When the patient made application for ad- vice, he had been blind a year. Before he lost his sight, he remarked, that, after any violent emotion, his sight at first grew. weak, and that ob- jects afterwards appeared double. When his cir- culation was at all hurried, he saw black spots _ before his eyes, and at length was quite blind, The vessels of the choroides were as large, as if they had been injected with wax, and every kind of surgical assistance proved ineffectual. (Ver- mischte, Chir. Schriften, B. 2, p- 12, &c. 8vo Berlin, 1786.) Insome cases, according to Beer, double vision only occurs, when the patient looks at objects with both eves, and it ceases as soon as he shuts either the diseased or the sound eye. In the last of these circumstances, double vision only originates from the deviation of the unsound eye from the axis of sight; but, in the first instance, it arises from the morbid state of the retina itself of the diseased eye. For the purpose of di- stinguishing both these examples of diplopia from every other species of symptomatic double vision, Beer applies to them the name of diplopia nervosa, _A degree of squinting, strabismus, therefore, is 4 very common symptom of incipient amaurosis, particularly when only one eye is affected : for, this always deviates more or less from the axis of vision. It is owing to this loss of correspondence, that persons, affected with an imperfect amaurosis of one eye, often mistake the relative distance of objects, and frequently see them reflected, ( T'ra- vers’s Synopsis, p.170.) It is less usual for im- perfect amaurosis to be accompanied with what Beer terms obliquity of the eye (Luscitas) ; either a paralysis, or a ceaseless, irregular action of one or more of the muscles of the organ, being evi- dently a condition of this symptomatic appear- ance. (See Beer's Lehre von den Augenkrank- heiten, B. 2, p. 427.) Beer has often met with patients labouring under imperfect amaurosis, who could plainly distinguish all objects which were not very small ; but saw them of a different colour from their real one ; for instance, yellow, green, purple, &c. (Visus coloratus ; crupsia,) He had under his care an amaurotic woman, who at mtidday could discern even the smallest objects in a strong light ; but they all appeared yellow, though no marks of jaundice were perceptible. Sometimes in the early stage of amaurosis, all 17 objects appear quite distorted, bent, shortened, and, in rarer instances, inverted. (Visus defi- guratus ; Metamorphosia.) ‘Thus the flame of a candle appears very long, but all awry. This is said by Beer to be constantly an unfavourable omen, as the cause of it lies in the brain itself. Imperfect amaurosis is sometimes attended with considerable shortsightedness (A/. yopia) ; and sometimes with the opposite affection (Pres- byopia) ; an infallible proof that essential changes have happened either in the transparent media or in the muscles of the eye. Many patients, when first attacked with amau- tosis, everywhere testify a partiality to a great quantity of light, employing several candles at night, and sitting in the day-time with their backs against a sunshiny window, in order to let what- ever they are reading have a very strong light upon it. This symptomatic appearance of inci- pient amaurosis is termed by Beer, Lichthunger. Amaurosis may either take place in an instant, even so as to be attended with entire blindness ; or it may come on quickly, that is, it may be complete in a few days or weeks ; or, lastly, what is most frequently the case, it may be produced gradually, and several years elapse before it attains its utmost degree ; circumstances of great mo- ment in the diagnosis and treatment. - ‘The type, which the disease assumes in its course and development, is also subject to great variety, and claims the utmost attention; for, amaurosis may either be permanent, or tem- porary. It is sometimes an intermittent disorder, making its appearance at regular or irregular in- tervals. In certain examples, it prevails at par- ticular times, commonly all day, till a certain hour; or from one day till the next; or at a stated time every month. The attacks sometimes take place at indeterminate periods. In parti- cular cases, another morbid affection is associated with the impairment of sight. Richter mentions a man, who became blind at twelve o’clock in the day, when the upper eye-lid used to hang down paralytic. The attack always lasted twenty-four hours. On the following day, at twelve o’clock, the sight used to return, and the patient then suddenly regained the power of raising the upper eye-lid. He would continue thus able to see for the next twenty-four hours. Whenever he took bark, the disease was regularly doubled; that is to say, the man then alternately remained blind forty-eight hours, and recovered the power of seeing for only twenty-four. In another pa- tient, cited by the same writer, the aqueous hu- mour, during the blindness, always became dis- coloured, whitish, and turbid ; but its transparency regularly returned on the cessation of the attack. According to Richter, the periodical amaurosis commonly depends upon irritation affecting the di- gestive organs, the stimulus of worms, or irre- gularity in the menstrual discharge. Sometimes, it is plainly a symptom of a confirmed ague, the patient being attacked with an ordinary intermit- tent, and blind during each paroxysm, but. always regaining his sight as soon as each fit is over. (Anfangsgr. der Wundarzn. B.3, Kap. 14.) Beer believes, that periodical amaurosis is chiefly observed in chlorotic, hemorrhoidal, hysterical, and hypochondriacal subjects. Dayblindness (Cecitas Diurna; Nyctalopia;) and nightblind- ness (Cacitas Crepuscularis ; Herman slon's 3)