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Show 01" THE ARTIFICIAL PUPIL. W J: OF THE ARTIFICIAL YUPIL. In deep inflammation of the eye, following the operation r . ,.-.¢..4-,.:...:.-A~/.-r«;.l of extraction or depression of the cataract, the pupil contracts and closes altogether ; for during the inflammation there being also great irritability of the eye, attended with contraction of the pupil, the iris fixes and adheres, so that there is an entire obstruction to the light. The contraction of the pupil is some- times more unaccountable, being gradual, and only accompa» or Inn ARTIFICIAL NHL. 69 tion, so that the aqueous humour becomes turbid, the pain is greater than in the depression of the cataract, and for these. reasons the motion of the needle should be decided and quick. Some time ago, before I had occasion to consider this subject of the contraction of the natural pupil, a patient applied to me who had an opacity of the cornea, covering the natural pupil. As the gentleman possessed the sight of the other eye, I did not advise an operation, which yet I thought practicable, if he had been blind altogether. Ithought of opening the iris opposite to the transparent part of the cornea. nied with a slight degree of unusual irritability in the eye. new mom t t . t it: .(a . lens, if it has not been extracted. These sketches of the eye will illustrate what I conceived it possible to do. In figure I. the opaque cornea at A, covers the pupil, the relative place of which is marked by a circular line of dots. In figure 2. I have represented a pupil formed by cutting the iris opposite the transparent part of the cornea. A, the opacity of the cornea covering the natural pupil. B, part of the iris seen. C, the artificial pupils. It is made to advance as far as the upper and internal part of the outer margin of the iris, viz. on the side next the nose. The point of the needle is then made to pierce the root of the iris, where it is attached to the ciliary ligament, and when the surgeon sees the point of the needle projecting through the outer margin of the iris, he draws the instrument towards him, so as to separate the iris from the sclerotic coat. Blood is ettused during the opera-v ' Ihave at present a gentleman under my care for stricture in the urethra. who has submitted to the operation of extraction of the cataract on one eye The operation has been very successful, but on the other eye the operator has been obliged to bring the point of the knife out at a wrong place, and now the scar of the incision begins at the margin of the cornea and turns in with a spiral line so as to cover the pupil. With this eye the gentleman cannot see but very obliquely, and imperfectly, although the pupil is quite clear ofcataract. In such a case as this, supposing that vision was not perfect in the other eye, the sight might be restored, by making an artificial pu- pil in the iris opposite to the transparent part ofthc cornea ‘ rdog-L-ynj- 53.3.33." fa-fik‘m "4...: . _. .. sq". ‘ . ~2-m- 7;":- w-'- 1-: i; The contraction of the pupil is, however, a rare complaint. One should naturally suppose that it would 'be an easy operation to introduce the couching needle, and cut the iris in the middle part, so as to enlarge the contracted pupil, or form a new one. But it is found, that when the pupil is made in the centre of the iris it quickly closes again. So it happens when the circle of the iris is divided from the circumference through its edge. Scarpa has substituted another operation, of which I should say little, not having performed it on the human eye, were I not certain of its practicability by trial on brutes, and did I not conceive that it is a means of restoring sight in a case not yet thought of.--Scarpa performs the operation in this way :Thc patient is seated as for the operation on the cataract. The surgeon uses a very small, straight couching needle. He perforates the sclerotic coat, as for the depression of the cata« ract, and about two lines from the margin of the cornea; the point of the needle is carried behind the iris, and before the |