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 The sharp-pointed knife is introduced into the anterior chamber and then rapidly withdrawn so as not to lose the aqueous.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
Indications. Sclerotomy is an operation undertaken for the relief of increased intra-ocular tension. It is performed—
(i) Usually as a secondary operation when iridectomy has failed.
(ii) As a primary operation for the division of anterior synechiæ causing tension.