Oldalképek
PDF
ePub

On the Morbid Sensibility of the Eye, commonly called Weakness of Sight. By Jous STEVENSON, Member of the Royal College of Surgeons, Sc. Syo, London, 1810. p. 108. Highley.

EVERY practitioner has heard more than he has seen of a disease of the eye, under the vague appellation weakness of sight." This complaint being often esteemed, in certain stages of its progress, rather an inconvenience than an actual disease, has, too generally, been treated with some domestic remedy, or with advertised nostrums. It is no question, but the profession, and society at large, are greatly indebted to those authors who elucidate what have been called minor complaints, with that degree of scientific clearness which makes them rationally understood. The dextrous operator, the describer of unusual occurrences, and the investigator of irremediable. calamities, have had, in great abundance, their historians and their culogists. Mr. Stevenson has sought, and we doubt not, will find reputation in a less brilliant career. In proportion to the frequency of the disease on which he treats, in proportion to the obscurity in which it has hitherto remained, and in ratio agreeing with the precision with which he describes its phenomena, and points out the mode of treatment, will be his claims on public gratitude.

THE Complaint which makes the subject of this pamphlet, Mr. Stevenson. considers as a " Morbid sensibility of the Eye," and that it has not hitherto been described by writers as a distinct disease, and only incidentally noticed: that its remote and proximate causes have been misunderstood, and its cure unfounded on a rational pathology. In endeavouring to give our readers a distinct view of this disease, its causes, and its treatment as stated in this pamphlet, we shall, in a degree, deviate from the arrangement of Mr. Stevenson. According to our idea of perspicuity it will be proper to give a description of the disease, with its usual symptoms; explain its predisponent, exciting, and proximate causes; and conclude with stating the method of cure.

[ocr errors]

1st. Description of the Disease.

By simply inspecting the eye, it is scarcely possible to recognize the existence of this complaint, as there is not the slightest external ophthalia; or unusual fullness in the vessels of the conjunctiva, any apparent affection of the biliary glands, nor the least visible organic derangement. The characteristic symptoms are, a morbid sensibility of the eye to light, and different kinds of external stimuli. According to the accurate observations of the late venerable Dr. Heberden, « Oculi K2 $131

[ocr errors]

si vel levissime sint imbecilles, quamvis nullam morbi notam præ se ferant, agre patiuntur ventum, ignem, pulverem, aut lectionem. Com ment. de morbis oculorum.) A strong glare of light is always painfully distressing to the patient; and hence, in aggravated cases of this dis ease, the effulgence of the Sun's rays when admitted to the Eye, excites in it a very acute sensation, which is accurately referred to the bottom of the orbit; around which there is at the same time, a sense of tension and oppressive uneasiness. For the same reason, the patient is miserably uncomfortable in a brilliantly illuminated apartment. In order therefore to exclude the strong and direct rays of light, he instinctively depresses his eyebrows, or applies his hand to his forehead, viewing objects with the palpebræ half closed, by which he is apt to acquire the habit of blinking. If he attempt to read, or look at small or bright objects, he is soon dazzled, and his vision becomes confused, which added to the pain the effort occasions, speedily compels him to desist. The iris acts with great energy on the admission of the rays of light to the retina, and in consequence, the pupil becomes contracted to a very small aperture; a striking feature of this disease. When the stimulus of light affects the Eye, there is sometimes, though very rarely, a manifestly deficient action of the lachrymal glands, but much oftener the secretion of tears is abundantly copious, which is indeed the principal cause of the confused vision occasionally attending this malady.

2d. Remote or predisposing Cause.

"General debility, however, induced, though not essential, seems greatly to predispose to this complaint. Hence, its most frequent occurrence to persons recovering from previous illness, and to those of a relaxed habit. Females are most obnoxious to its attacks, as the predisponent causes are most liable to arise in the low tone of their system. "Most of the instances of weakness of sight, occur under great con stitutional delicacy.

[ocr errors]

3d Exciting Cause.

Long or frequent exposure of the eye to a very vivid or reflected fight, or its excessive exertion in reading, or viewing minute and dazzling objects.

4th. Proximate Cause.

"The proximate cause of weakness of sight, instead of being a local debility, consists in an exquisite irritability and sensibility of the

I am assured by an intelligent and learned traveller, that the inhabitants who reside at the foot of the Glaciers in Switzerland, acquire this habit in a remarkable degree, in consequence probably of the vivid light that is reflected from the accumulated fields of ice and snow, to which they are perpetually exposed

+ Many people amongst the Ethiopians, Africans, &c. who have an extreme degree of tenderness of sight, owing to the great brilliancy of the Sun's Jays, suffer exceedingly, according to Haller, (Tom. v. p. 490.) from violent Epiphora, or watery eye, which in fact renders them nearly blind during the day.

retina

retina, the effect of great turgescency of the vessels, or a chronic inflammation of that membrane, or the choroid."

5th, The Cure. ·

The remote causes of this disease, or what have been understood to be its remote causes; as well as an obvious reasoning upon its exciting causes, led to an erroneous conclusion, and to a fundamental mistake in the treatment.

A morbid sensibility of the retina, the effect of exhausted nervous energy, was deemed to constitute the very essence of this complaint. On this hypothesis, the symptoms were com bated by the external application of sedative and tonic, and by the internal exhibition of corroborant and nervous remedies.

The compleat failure of this method led Mr. Stevenson to adopt an antiphlogistic and evacuating plan. His observations brought him to conclude,

"That the exquisite sensibility of the Eye might with more proba bility result from a chronic inflammation, or at least a highly turged condition of the blood-vessels of the retina or choroid."

"Agreeably to this supposition, the indications of cure must consist, not in giving additional tone by the use of cold astringent applications, and interual strengthening medicines, but in lessening the plethoric state of the vessels of the posterior membranes of the eye, and in obviating, at the same time, the exquisite sensibility of the retina."

On this principle, leeches were applied* to, generally, the

*The application of leeches so immediately in the vicinity of the eye, has been pointedly reprobated by a celebrated author on ocular complaints, because, says he, they have sometimes been found to occasion a considerable swelling of the lids, and have also, for a time, increased, instead of lessened the irritation of the eye. In order to prevent which mischief, he adds, it will be proper to apply the leeches to the hollow of the temple. In a very large number of cases in which I have known them applied to the lower eye-lid, under the direction of the late Mr. Saunders, as well as under my own, I have indeed very rarely witnessed the effects above alluded to; and where any inconvenience of the kind has occurred, it has been in highly irritable habits greatly disposed to erisypelas, in which cases the same consequences are apt to supervene even from the application of a blister. But I am convinced, from the fullest observation and experience, that the benefit they afford the patient when placed as near as possible to the inflamed eye, infinitely exceeds what the same number are capable of yielding, by being laid on the temples, and more than compensates for the greater degree of ecchymosis, which I admit is more prone to take place by the extravasation of blood into their loose reticular texture, than into the denser cellular membrane of the temples, and which temporary inconvenience constitutes

under eye-lid; cathartics were employed, and managed in a way which Mr. Stevenson explicitly describes: Fomenta

the principal, if not the only real objection against their application to the lower eyelid.”

Having ourselves observed the inconvenience here stated, and also a troublesome ulceration when leeches have fixed on the upper eye-lid, we are gratified in stating the opinion of a gentleman of much practical knowledge, on a point often important in private practice, in more than one view. When an ecchymosis does take place, Mr. Stevenson recommends aq. ammon. reduced with water, or the juice of Solomon'e real, for removing it. We have often had an opportunity of observing the advantages that arise from attending to emporistic medicines. The Solomon's seal (Convallaria multiflora Linn.) affords an instance of an indigenous plant that deserves investigation. It is so common as to be found in the woods of many, if not all the English counties; is perennial, flowers in May and June; and has been long known, as a popular remedy for removing ecchymosis very speedily. The proTessors and pupils of the pugilistic schools are well acquainted with this fact. It may be worthy of enquiry whether the reputed effect of Convallaria multiflora in hernia, has any actual foundation. Applied to the protruded part, and given internally in powder and infusion, it was once thought to be useful. If mixed with its congenors the Convallaria matalis, C. verticillata, and C. polygonatum, would its properties be improved?

↑ «Purgative medicines as exhibited by practitioners in general, for the acute inflammation of the eye, whether external or internal, have been given much too sparingly, both in regard to their dose, and to the times of their repetition. If they be meant to produce any decidedly good effect, they must at first be administered in a full dose, so as to excite an immediately copious evacuation, and repeated afterward in such a way as to keep up a conssant determination to the bowels. Should the patient be of a robust habit of body, nothing is so effectual for that purpose as a full dose of calomel with autimonial powder, and in two hours afterward, a sufficient proportion of powdered jalap, and double the quantity of cream of tartar in mint water, or gruel; by the operation of which, a large discharge of serous fluids is solicited, and the vigor and activity of the general circulation sensibly diminished. Jo more delicate constitutions the calomel must be given sparingly, and in ien of the jalap, an adequate quantity of magnesia vitriolata in infusion of senna. 22

་་་

have repeatedly observed, Mr. Stevenson adds, that gentle apperients in these cases make no impression upon the disease; but, if the operation of the remedy be powerful, the most manifest advantage is certainly obtained. In the management of this class of remedies, it is customary to allow two or three days to intervene before they are again repeated, by which time the effects of the first dose have wholly subsided, and little comparative advantage is gained. On this account the cathartic should be employed in a full dose, and as frequently as the patient can

bear.

used warm, and composed of narcotic substances, in an aqueous decoction*. These were applied morning and ever

bear. The object is not only to lessen the actual quantity of circulating fluids, but also to prevent their immediate accumulation, and the consequent distention of the vessels upon which the inflammation depends. This purpose should be effected by the observance, at the same time, of a strictly antiphlogistic regimen, allowing only a small quantity of diluting liquids, and by interposing between the active purgation, small quantities of emetic tartar, combined with some mild saline aperient, repeated so as to keep up a constantly moderate diarrhoea." In every species of acute ophthalmia, and in every kind of inflammation, or fullness of the vessels of the eye, Mr. Stevenson found this method effectual; and often superseding the necessity of repeated topical bleedings. This practical fact, so fully confirmed by Mr. Stevenson's experience, was undoubtedly known to HIPPOCRATES, who asserts, Aphorism 17, section 6. Lippitudine laborantem alvi profluvio corriti, bonum ; and succeeding practitioners have availed themselves of it. Celsus says,

omnite dejectio lippiendi prodest. {Lib. 4, cap. 8, page 77, Svo Edit. Biponte, 1786,) and the annotators on Hippocrates subjoin, “Ratio est, quia fit revulsio a supernis deorsum materie sive humoris ophthalmiam fatientis. Debet ergo Medicus naturam imitari, cum illa morbum sanat. Cardan. p. 622, Conf. Duret. in Coac. p. 129. Enim vero optime caput ab humorum affluxu liberant laxantia, veletiam pro circumstantiarum ratione purgantia. Et Galenus gravis testis est, nonnullos, quibus oculi inflammati, sola purgatione per alvum una die sanatos. Hoffm. Med. Rat. T. 4, S. 1, p. 525. We believe, however, that the fact has never been so strongly put as by Mr. Stevenson.

*For the fotus Mr. Stevenson employed the capsule of the poppy, chamomile flowers, rosemary, and eyebright infused in hot water, but confesses he is unable to determine if any of these substances augmented the efficacy of the water. Are we to suppose the Euphrasia officinalis was employed because it was formerly in repute as a remedy for impaired vision, and even had the power to make old eyes again young. Tantum esse, ait, Euphrasie in imbellicate visus vim atque efficaciam, ut ejns usu septuagenari os quosdam, propter vigilias et studia plurima amissa visu, in decrepita isth etate, cum recuparasse observaverit. These are the tales of other times. We have more satisfaction in resting on the strong evidence of the efficacy of the long neglected digitalis. I cannot omit to state, says Mr. Stevenson, (p. 77) that I have used a warm decoction of digitalis (pupurea), with the effect of diminishing, materially, the exquisite sensibility of the eye; nor does its application produce any uneasiness, like the different preparations of opium. In violent inflammations of the eye, the decoction of this plant has been used with marked success by Dr. Haworth;-in the most severe attacks of the Egyptian ophthalmia it has alleviated the suffering-and it has been extensively employed, in strong infusion, to the inflamed eyes of horses, with similar results. Saffron in the form of a warm infusion tends also. Mr. Stevenson assures us, most powerfully to take off the morbid sensibility of the eye.

« ElőzőTovább »