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Cataract.

Cataracts differ in

Gen. I. without the crystalline capsule, between its anterior Parocais. hemisphere and the iris, and consequently constitutes a Catarracta. distinct disease, embracing several modifications of par

• opsis Glaucosis.

. Cataracts are of different colours and of different decolour and grees of consistency from circumstances influencing the consistency. morbid action with which we are but little acquainted ;

and as little with the occasional causes of such action, though old age seems to be a common predisposing cause. They are, therefore, black, white, leaden-hued, ferruginous, green, amber; as they are also fluid or milky, soft, firm, hard, horny, and even bony, for they have been sometimes found of this last texture *. They are not unfrequently the result of an hereditary taint, adhering to generation after generation, and appearing either congenitally, or by a very general predisposition

afterwards. The consist. From the colour of the cataract no conclusion, in the be gathered opinion of that acute observer Mr. Pott, can be drawn in from the regard to its consistence; but he thinks that when the colour soft cataract,

opake crystalline is perfectly dissolved so as to form a what ; hard soft cataract, it is somewhat enlarged; and that when

such dissolution does not take place, and a hard cataract is produced, the crystalline is in some degree lessened. The hard cataract has also been distinguished by the name of ripe, as the soft by that of unripe. “But if we would think and speak of this matter”, observes Mr. Pott, “ as it really is, we should say that a dissolution or softening of the crystalline lens is by much the most common effect; and that seven times out of nine, when it becomes opake, and tends to form a cataract, it is more or less softened: the softening sometimes extending through the whole range of the lens and sometimes through only a part of it; while, however, the part that remains undissolved is rarely, if ever so firm as the centre of the sound crystalline.” Mr. Pott proposes it as a

cataract.

. Wenzel, Traité de la Cataracte avec des Observations. Paris, 1786. Guthrie's Lectures, &c. on the Eye, p. 208.

soft cataracts of slow

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Beer.

cataract.

question, whether cataracts, which have been found per- Gen. I.

Spec. IX. fectly soft, have not in general grown opake by slow

Paropsis degrees ? and whether those which have been discovered Catarracta.

Cataract. to be firm have not become opake hastily, and been pre

Whether ceded by, or accompanied with, severe and deep-seated pain in the head, particularly in the back part of it?* There is no ophthalmologist, however, who has paid

and firm of so much attention to this subject as Professor Beer; and rapid though his divisions are perhaps a little too minute, yet growth?

Minute but the microscopical accuracy with which he has followed up all the modifications of the cataract are entitled to our remarks of most serious attention. He agrees with Mr. Pott that a hard cataract is always comparatively small, though he adds that every small cataract is not necessarily hard, He is peculiarly minute in examining all the qualities which the disease may exhibit of position, colour, shadow, The verifi

cation of a shape, range ; together with the mobility and degree of prominence of the iris; and till all these characters have been accurately weighed, he hesitates to determine as to the variety of the cataract; or, in effect whether it be a cataract at all. The shadow cast by the iris constitutes his leading clue. If the lens in an opake state maintain Character the size it possest when transparent, there is a manifest shadow thrown back upon the surface of the cataract by by the iris. the iris. If the cataract be less than the natural lens, this shadow is broader than usual. If the opake lens be swollen no shadow is present, as the capsule is pushed forward into contact with the iris, and the posterior chamber is abolished. And by carefully comparing all the signs that lie before him, he is able to indicate with certainty, in every instance, the seat, the size, and the consistence of the cataract.

We have already observed that a cataract is occasion. Sometimes ally the result of an hereditary taint; in other instances it per originates spontaneously, or from causes we cannot trace. ditary taint. It has, however, often followed upon convulsions, chronic Occasional

of the shades cast at times Cataract.

roduced

here

causes.

• Chirurgical Observations relative to the Cataract, &c. 8vo. 1775. London.

VOL. IV.

cataract, cause and

Gen. I. head-ache, syphilis, rheumatism, suppressed perspiration, • SEC. IX.

and in a few instances trichosis Plica, or matted hair*. Paropsis Catarracta. It has also appeared as an effect of inflammation, produc

ed by a thunder stormt. Siliquose The siliquose or bean-shaped cataract is usually the

result of a wound or rupture of the capsule, through which character. the aqueous humour is admitted to the lens. In children

this mischief is occasionally produced by those fits of convulsion to which they are subject as soon as born, and during which the muscles of the eye-ball are affected with violent spasms 1. At this age the opacity is a light gray, and evidently has its seat in the anterior capsule, which is shrivelled and wrinkled. In adults the opacity is chalky, when the capsule has been wounded ; otherwise it is dusky or yellowish ; and the kernel of the lens usually remains, while its surface and circumference are dissolved. The opacity is flat; and the shadow of the iris broad. From its occurring occasionally in infants soon after birth,

it is often confounded with a genuine congenital cataract. Has been Like PAROPSIS Glaucosis or humoral opacity, it has cured spontaneously, sometimes ceased spontaneously, or without any manifest ceased sud- cause &; and Helwig gives an instance in which the cessadenly, and carried off' tion was not only spontaneous but sudden ||. It has also, by a fever. at times, been carried off by a fever T. Hence me. There is hence, specious ground for conceiving that dicine might some medicine might be discovered capable, by some genebe supposed serviceable: ral or specific action, of producing a like change, and

proving a remedy for the disease ; and the more so as we find ganglions and other accidental deformities frequently

removed from the extreme parts of the system by external but no ge- or internal applications. But no such remedy has hitherto neral or specific re

been descried, or at least none that can be in any degree medy has been discovered

* De la Fontaine, Chirug. Med. in the curative + Richter, Chir. Bibl. Band. vi. 158.

Beer, ut suprà. process

§ Haggendorn, Observ. Med. Cent. 1. Obs. 50. Franc. 1698, 8vo. Ludolf, hitherto Miscell. Berol. Tom. iv. 258. Walker, On the Theory and Cure of a Cataract. pursued.

|| Observ. Physico-Med. 23, Aug. Vind. 1680, 4to.

Velschius, Episagm. 20.

Cataract.

rations,

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relied upon, excepting in those cases of supposed but mis- Gex. I.

Spec. IX. called cataracts, which have consisted in a deposition of

Paropsis lymph from an inflammation of the iris and ciliary processes: Catarracta. for recourse has been had to mercurial preparations both external and internal, as well as almost every other metallic salt, aconite, the pasque-flower, or pulsatilla, to protracted vomiting, electricity, and puncturing the tunics of the eyes, but without any certain advantage*. This is the This to be

lamented, more to be lamented, because whatever surgical operation because of may be determined upon as most adviseable, there is no the ill-sus

cess of guarding, on all occasions, against the mischievous effects many opewhich may result, I do not mean from the complication or rat

even when severity of the operation, for this, under every modifica dexterously tion, is simpler and less formidable than the uninitiated performed. can readily imagine; but from the tendency which is illasu sometimes met with, from idiosyncrasy, habit, some peculiar acrimony, or other irritable principle, to run rapidly into a state of ulcerative inflammation, and in a single night, or even a few hours, in spite of the wisest precautions that can be adopted, to endanger a total and permanent loss of vision. I speak from personal knowledge, Illustrated. and have, in one or two instances, seen such an effect follow, after the operation had been performed with the utmost dexterity, and with every promise of success; and where a total blindness has taken place in both eyes, the operation having been performed on both ; neither of them being quite opake antecedently, and one of them in nothing more than an incipient state of the disease, and the patient capable of writing and reading with it. And Hence all hence it is far better, in the author's opinion, to have a

should be trial made on one eye only at a time, and that the worst, had recourse

to with where both are affected and one is still useful, than to subject both to the same risk; for the sympathy between them is so considerable, that if an inflammatory process from any constitutional or accidental cause should show

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caution,

• Beytrage zur Chirurgie und Augenheilkunst. Von Franz Reisinger, &c. Göttingen, 1814.

modes of

known to

and Romans:

al

Gen. I. itself in either, the other would be sure to associate in the Spec. IX. morbid action. Paropsis Catarracta. The usual modes of operating for the cure of a cataract Cataract.

are three; that of couching or depression : that of extracUsual

tion: and that of, what is called, absorption* The first operating. was well known to the practitioners of Greece and Rome; Couching ;

; and is ably described by Celsus, who advises, in cases or depression. where the lens cannot be kept down, to cut it into pieces Extraction. with the sharp-edged acus or needle, by which mean it Absorption. will be the more readily absorbed. And, from this last Couching

remark, we have some reason for believing that even the the Greeks third of the above methods, that of absorption, was also

known at the same time; as it is probable, indeed, that Probably the second, or the operation by extraction, was likewise ;

since we find Pliny recommending the process of simple and extraction. removal or depression in preference to that of extraction

or drawing it forth ; “ squammam in oculis emovendam potius quàm extrahcndam "t, which Holland has thus honestly, though paraphrastically translated “ a cataract or pearl in the eye is to be couched rather, and driven

down by the needle, than quite to be plucked forth." Depression in the East, however, both these plans appear to have and ex been pursued through a much longer period. Both are traction known im- noticed by the Arabian writers in general, and especially memorially by Avicenna and Rhazes; and both seem to have been in the East.

practised from time immemorial in India, and, according to the account of the cabirajas, with wonderful success. Dr. Scot was informed by one of the travelling operators, who, however, spoke without a register, that in the operation of depression this success was in the proportion of a hundred who were benefited to five who obtained no

advantage whatever. Willburg's Upon the ordinary operation of depression M. Willoperation of burg seems to have made a considerable improvement, by reclination.

pressing the cataract backwards and downwards into a particular position where it is less likely to ascend or touch

* Guthrie, Lect, on the Operative Surgery of the Eye, p. 184, 8vo. 1923. + Nat. Hist. Lib. xxix. Cap. I.

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