GEN. I. SPEC. IX. Paropsis without the crystalline capsule, between its anterior hemisphere and the iris, and consequently constitutes a Catarracta. distinct disease, embracing several modifications of paropsis Glaucosis. Cataract. Cataracts differ in colour and Cataracts are of different colours and of different degrees 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 *. The consist ency not to from the colour: cataract. 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. From the colour of the cataract no conclusion, in the be gathered opinion of that acute observer Mr. Pott, can be drawn in regard to its consistence; but he thinks that when the 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 Wenzel, Traité de la Cataracte avec des Observations. Paris, 1786. Guthrie's Lectures, &c. on the Eye, p. 208. per GEN. I. SPEC. IX. soft cata racts of slow growth? and firm of rapid growth? Minute but accurate Beer. question, whether cataracts, which have been found fectly soft, have not in general grown opake by slow Paropsis degrees? and whether those which have been discovered Catarracta. to be firm have not become opake hastily, and been pre- Whether Cataract. 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 so much attention to this subject as Professor Beer; and though his divisions are perhaps a little too minute, yet 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 verifishape, 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 of the shades shadow thrown back upon the surface of the cataract by 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. cation of a cataract. cast at times by the iris. produced from here We have already observed that a cataract is occasion- Sometimes ally the result of an hereditary taint; in other instances it originates spontaneously, or from causes we cannot trace. It has, however, often followed upon convulsions, chronic Occasional Chirurgical Observations relative to the Cataract, &c. 8vo. 1775. London. VOL. IV. ditary taint. causes. GEN. I. SPEC. IX. Paropsis Catarracta. Cataract. Siliquose cataract, cause and character. Has been cured spontaneously, ceased suddenly, and carried off by a fever. Hence me head-ache, syphilis, rheumatism, suppressed perspiration, and in a few instances TRICHOSIS Plica, or matted hair *. It has also appeared as an effect of inflammation, produced by a thunder storm†. The siliquose or bean-shaped cataract is usually the result of a wound or rupture of the capsule, through which 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. 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. Like PAROPSIS Glaucosis or humoral opacity, it has sometimes ceased spontaneously, or without any manifest cause §; and Helwig gives an instance in which the cessation was not only spontaneous but sudden ||. It has also, at times, been carried off by a fever¶¶. 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 or internal applications. But no such remedy has hitherto been descried, or at least none that can be in any degree but no general or specific re medy has curative process hitherto pursued. * De la Fontaine, Chirug. Med. + Richter, Chir. Bibl. Band. vi. 158. + Beer, ut suprà. § Haggendorn, Observ. Med. Cent. 1. Obs. 50. Franc. 1698, 8vo. Ludolf, Miscell. Berol. Tom. iv. 258. Walker, On the Theory and Cure of a Cataract. Observ. Physico-Med. 23, Aug. Vind. 1680, 4to. Velschius, Episagm. 20. GEN. I. Paropsis This to be lamented, because of the ill-suomany operations, cess of even when dexterously Causes of relied upon, excepting in those cases of supposed but miscalled cataracts, which have consisted in a deposition of SPEC. IX, lymph from an inflammation of the iris and ciliary processes: Catarracta. for recourse has been had to mercurial preparations both Cataract. 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 more to be lamented, because whatever surgical operation may be determined upon as most adviseable, there is no guarding, on all occasions, against the mischievous effects which may result, I do not mean from the complication or severity of the operation, for this, under every modifica tion, is simpler and less formidable than the uninitiated performed. can readily imagine; but from the tendency which is ill-success. 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 shee trial made on one eye only at a time, and that the worst, 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 operations had recourse to with caution. Beytrage zur Chirurgie und Augenheilkunst. Von Franz Reisinger, &c. Göttingen, 1814. GEN. I. SPEC. IX. Paropsis Catarracta. Cataract. Usual modes of operating. Couching; or depression. the Greeks itself in either, the other would be sure to associate in the morbid action. The usual modes of operating for the cure of a cataract are three; that of couching or depression: that of extraction and that of, what is called, absorption*. The first was well known to the practitioners of Greece and Rome; and is ably described by Celsus, who advises, in cases 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 known to remark, we have some reason for believing that even thè third of the above methods, that of absorption, was also known at the same time; as it is probable, indeed, that the second, or the operation by extraction, was likewise; absorption: since we find Pliny recommending the process of simple removal or depression in preference to that of extraction or drawing it forth; "squammam in oculis emovendam potius quàm extrahendam "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." and Romans: Probably and ex traction. Depression and extraction known immemorially in the East. Willburg's reclination. In the East, however, both these plans appear to have been pursued through a much longer period. Both are noticed by the Arabian writers in general, and especially by Avicenna and Rhazes; and both seem to have been 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. Upon the ordinary operation of depression M. Willoperation of burg seems to have made a considerable improvement, by 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. 1823. + Nat. Hist. Lib. XXIX. Cap. 1. |