The principal complications of the pro cedure are iritis and secondary glaucoma.
The first is supposed to be caused either by pressure or "chemical irritation" ex erted by the lens-matter on the iris. As a rule, it may be prevented by keeping the pupil well dilated with some power ful mydriatic or combination of mydri aties. If the second form of complica tion appears, the lens-matter should be immediately removed by extraction through a linear incision.
In traumatic cataract the patient should be placed in bed as early as pos sible. Ice-compresses should be applied either constantly or intermittently to the eye in order to reduce inflammatory reaction, and atropine should be in stilled at regular intervals to prevent the occurrence of iriclic inflammation. Or dinarily under such plan of treatment, the lens-substance will gradually absorb without any complicating disturbances. The danger of secondary- glaucoma with its accompanying symptoms should never be lost sight of, and intra-ocular tension should be repeatedly tested. If such symptoms should intervene, as much of the lens-matter as proper at the time should be removed without delay. This may be readily accomplished by a sim ple incision through the cornea into the anterior chamber and tbe soft ened lens-masses carefully and gently coaxed out along the groove of a Daviel spoon.
In operating upon shrunken or mem branous cataracts, it is not so essential to provoke absorption of the remaining cataractous material as it is to obtain a clear space in the toughened and opaque capsule through which vision can be gotten. The operation is ordinarily performed by means of two needles which are passed rather obliquely through the cornea, one near to the nasal and the other close to the temporal border of the membrane. This done, both are pushed backward into the chosen portion of the opacity, and the points of the instruments separated from one another in such a manner that no traction is exerted upon the iris and ciliary body, thus producing a clear hole in the membranous mass.
Complete atropinization of the eye be fore extraction of cataract is extremely favorable to the successful issue of the operation. Confirmed by a frial of the method in 170 eases. Out of these. pro lapsus of the iris occurred only in 7 eases,—i. e.. 4 per cent., while before the
use of atropine the percentage of pro lapsus was 15. Aluttermilch (Gazeta. Lekarska, No. 9, '90).
Simple linear extraction is applicable to the removal of both the soft and the membranous varieties of opacity. It is preferred by many operators to discis sion, and may be employed in any case where the lens-substance is sufficiently soft to flow through a small corneal wound.
The 'operation is performed as fol lows: After a speculum has been in serted, or the eyelids separated by an assistant, the globe is grasped by a fixa tion-forceps, and the point of a kera tome or the tip of a von Graefe knife is entered into the anterior chamber through the Cornea, usually about three or four millimetres from the limbus. If the former instrument is used, it is passed directly through the corneal raembrane, but, as soon as its tip enters the anterior chamber, the cutting-blade is laid upon a plane that is parallel to that of the iris. It is then pushed forward until the corneal wound has obtained a length of several millimetres. It is then slowly withdrawn, in order to prevent the aqueous humor from coming away too quickly, with the possibility of a prolapse of the iris. If a von Graefe knife is used, the movements given to the instrument must be very- carefully performed, in order to avoid wounding the iris-tissue. A cystotome is passed into the anterior chamber through the same corneal wound, care also being taken to avoid wounding the iris. Free incision in the anterior capsule of the lens is then made with it. After the incisions have been accomplished, the cystotome is withdrawn, and the loosened lens-matter is evacuated, as previously explained,by means of a Daviel spoon. If necessary, the operation may be done with the addition of an iridectomy. In this event, the corneal incision is ruade nearer the limbus and should be slightly longer. After the withdrawal of the knife, the tips of an iris-forceps are to be introduced into the anterior chamber and a fold of iris directly over the sphincter of the pupil grasped and gently drawn through the wound and cleanly snipped ofi with a pair of fine scis sors. Cystotomy and extraction of the lens-massings then follow, a just de tailed.