_Second step._ The iris should be seized well in the periphery so as to avoid breaking up the growth; it is then withdrawn with the growth, and the latter removed. IRIDECTOMY FOR PROLAPSE OF THE IRIS This operation is usually performed for prolapse of the iris following a wound of the cornea or limbus, and may be attempted up to about the third day after the original injury. =Operation.= A general anæsthetic is usually desirable. The prolapsed iris should be seized with the forceps and withdrawn from the wound. A second pair of forceps is used to take a fresh hold on the iris, which can usually be drawn out further (Fig. 118). It is then divided as close to the corneal wound as possible. The iris usually flies back into the anterior chamber clear of the corneal wound by its own elasticity, but if it does not do so it should be freed with a spatula. The pupil should be kept subsequently under atropine. TRANSFIXION OF THE IRIS =Indications.= This operation is undertaken in cases of iris bombé when iritis is still present and when an iridectomy would subsequently lead to a drawn-up pupil. It is also of service to evacuate the contents of cysts of the iris (local iris bombé). [Illustration: FIG. 118. PROLAPSE OF THE IRIS THROUGH A PUNCTURED WOUND OF THE CORNEA. Method of withdrawing the iris by two pairs of iris forceps before removal.] =Instruments.= Speculum, fixation forceps, Graefe’s knife (narrow). =Operation.= The knife is entered at the limbus from the outer side directly opposite the occluded pupil. The apex of the iris bombé is transfixed and the point of the knife made to appear above the pupillary area; the iris bombé on the other side of the pupil is then transfixed and the knife is withdrawn. THE DIVISION OF ANTERIOR SYNECHIÆ =Indications.= Anterior synechiæ rarely require division unless they are likely to cause tension or the adherent iris is considered a source of danger to the eye on account of its liability to septic infection. If the synechiæ are causing tension, the method of division described under sclerotomy is probably the most satisfactory; otherwise the following method devised by Lang can be used. =Instruments.= Speculum, fixation forceps, Lang’s knives--one with a sharp point, and one blunt. =Operation.= Under cocaine. The incision is made at the limbus in a favourable situation for the division of the synechia. The sharp-pointed knife is introduced into the anterior chamber and then rapidly withdrawn so as not to lose the aqueous. The blunt knife is then inserted through the incision and, partly by cutting and partly by tearing, the synechia is divided in a direction from the periphery towards the pupil. The operation is not at all easy to perform, since the iris gives before the knife. Great care should be taken to avoid evacuating the aqueous, as the operation is thereby rendered much more difficult or even impossible. CHAPTER IV OPERATIONS UPON THE SCLEROTIC ANTERIOR SCLEROTOMY