Volume 2

The American encyclopedia and dictionary of ophthalmology / edited by Casey A. Wood, assisted by a large staff of collaborators.

Date:
1913-1921
Catalogue details

Licence: In copyright

Credit: The American encyclopedia and dictionary of ophthalmology / edited by Casey A. Wood, assisted by a large staff of collaborators. Source: Wellcome Collection.

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    entails the least risk is the one that should be chosen in all cases. Pog. sibly an experienced surgeon, who has his patient under full control in a thoroughly equipped eye hospital, with trained assistants, nurses etc., may take chances and do an extensive laceration of the capsule but the inexperienced surgeon will be wise if he proceeds more cau- tiously. In any case, it is not proper to do too much and thereby court disaster, an event which sooner or later is bound to happen even to the most experienced operator. The instruments required for a discission. The instruments required are an eye speculum, a fixation forceps and a Bowman’s needle. The eye speculum and forceps should be put into boiling water for five minutes, the Bowman’s needle for a few seconds; then all the instruments should be placed in a shallow tray containing absolute alcohol. Prior to use, they should be washed off in a four per cent, solution of boric acid. Position of the patient for discission. The patient should be reclin- ing upon an operating table. The surgeon when sitting behind the patient has much better control of the eye below, than in any other position, both as to seeing and operating. Local anesthesia is sufficient except in the very young or unruly, where general anesthesia may be necessary. The pupil of the eye to be operated on should be previously dilated ad maximum; the eyelids and eye brows should be made as sterile as possible. Then insert the eye speculum and flush the field of operation freely with a four per cent, boric acid solution. If ordi- nary daylight is not enough to give a clear view of the cornea, iris and lens, some form of artificial light with a condenser should be used. The surgeon then seizes the globe of the eye below, near the limbus, the eye is rotated downwards and the globe pierced with a Bowman’s needle. The point of entrance should be in the upper-inner (left), or upper-outer (right) quadrant of the eye, 2 mm. from the limbus, and in sclero-corneal tissue. The flat of the needle is held parallel to the plane of the iris, the point inserted under the conjunctiva, pushed through the sclera into the anterior chamber, the flat of the blade still carried parallel to the plane of the iris to the lower periphery of the capsule. Then the handle of the needle is raised and the cutting edge turned and brought in contact Avith the capsule, which should be cut by an upward pull of the needle to about 3 ram., penetrating into the lens fibers about 1 nim. (See the figure.) The needle is then Avithdrawn in the same manner that it entered the globe. If tlie shank of the needle is properly made, the point of entrance is so completely filled that no aqueous escapes. Care is to be exercised that the point of the needle does not become entangled in the