A course of operative surgery / with plates drawn from nature by M. Léveillé and coloured by hand under his direction ; by Christopher Heath.

  • Heath, Christopher, 1835-1905.
Date:
1877
Catalogue details

Licence: Public Domain Mark

Credit: A course of operative surgery / with plates drawn from nature by M. Léveillé and coloured by hand under his direction ; by Christopher Heath. Source: Wellcome Collection.

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    sclerotic with a narrow knife, and the fear of injuring the iris has been replaced by a systematic removal of a piece of that curtain, with the best results. In the modern operation (Fig. 7) the stop-speculum is introduced as in the operation for strabismus, and the operator being behind the recumbent patient, seizes a fold of conjunctiva and subjacent tissue with the forceps, immediately below the centre of the cornea. The eye being thus steadied and drawn down, a narrow knife, held lightly between the thumb and the first and second fingers, is entered at the outer border of the cornea (or behind the cornea, as preferred by some), at the level of the junction of its upper and middle thirds; the knife being directed slightly from before backwards, until it has entered the anterior chamber, so as to avoid splitting up the substance of the cornea, and also obliquely downwards so as to divide the inner co-extensively with the outer surface of the cornea. The entry into the anterior chamber will be known by the loss of resistance, and in the living or recent eye the point can be clearly seen. The knife is then to be brought horizontal, and to be steadily pushed on, so that the point may emerge at the corresponding spot on the opposite side, and having done so, is to be made to cut a corneal (or corneo-sclerotic) flap with a steady sawing movement. The next step is to excise a portion of the iris (iridectomy, Fig. 8), and for this purpose the forceps steadying the eye should be transferred to the charge of an assistant. With one hand the operator then lays the open blades of a pair of delicate angular scissors on each side of the wound already made, and with the other introduces a fine pair of iris-forceps by which the upper border of the pupil is grasped and drawn out between the blades, by the closure of which its separation is effected. The third step is the laceration of the capsule of the lens, which is done with the “ pricker,” usually mounted on the same handle as the curette. In using this instrument, it should be especially noted that the point of it is always turned the reverse way to that of the curette, and it should be introduced and withdrawn so that the point may not become entangled in the section or iris. Held horizontally, the pricker is intro- duced through the wound with the back downwards; it is then rotated, so as to bring the point against the capsule, which it is made to tear both vertically and across; after which, by another half turn, the back will be brought upwards, and the instrument can be withdrawn. In lacerating the capsule, the operator has no sensation of resistance to guide him, and must be careful not to push the pricker too deeply, and so dislocate the lens with its capsule.