REMOVAL BY SNARE
Indications. Operation with the snare is indicated in cases of simple mucous polypi, if only a few polypi are present, and no sinus suppuration is suspected. It is a suitable method for the removal of papilloma, fibroma, and bleeding polypus of the septum. The snare is also serviceable in the removal of enchondroma, osteoma, and growths, if of limited size, after they have been detached from their bases or broken up with a chisel or bone forceps.
Instruments. The surgeon will employ the pattern of snare to which he is accustomed. The simpler models, such as those of Krause, or some modification of Blake’s instrument, such as that of Badgerow, when threaded with No. 5 piano wire will be found sufficient in most cases (Fig. 312). For tougher growths, or those with a thicker pedicle, the snare of Lack can be recommended. It is threaded with heavier wire, and by a screw arranged in the handle the loop can be slowly and steadily contracted.
Operation. The nose is carefully prepared with cocaine and adrenalin (see [p. 573]), remembering that any growth or polypus is itself insensitive. The anterior part of the nasal cavity, and particularly the septum, should be thoroughly anæsthetized.
Under good illumination the snare is introduced with the loop vertical, and passed alongside the growth,—between it and the septum or to the outer side, as space permits. It is then swept round a half-circle, so as to bring any tumour within the loop, and by a to-and-fro movement the snare is worked upwards towards its base. The attachment of the ordinary mucous polypus is generally in the region of the middle meatus. The wire loop is thus threaded on to the growth or polypus. The loop is now steadily tightened until it is felt that the pedicle is grasped,—it is seldom visible. By a quick movement of avulsion the tumour is then torn from its attachment. This will bring away some of the œdematous tissue on the distal side of the loop, and there will be less tendency to recurrence than if the root were simply cut across. With the removal of a first polypus others come into view and they must be treated in the same manner. The number which can be removed at one sitting will depend on how well the patient is able to bear the manipulations and how much bleeding there is. If both nostrils be affected it is well to treat them on alternate weeks.
When the growth slips, or is pushed backwards, it can be brought forward into the field of operation by asking the patient to blow down the nose, with the opposite nostril closed. Or the presenting part of a polypus may be seized with a pair of toothed catch-forceps and the wire loop slipped over this.
If the growth be hanging backwards, and presents in the post-nasal space, as it often does when it originates from the mucosa of the maxillary antrum, it may be necessary for the surgeon to introduce his left forefinger behind the palate,—as described on [p. 590] (compare [Fig. 291]),—so as to steady the growth and at the same time slip the wire loop around it. If there be no space for the latter manipulation, the left forefinger is used to steady the mass while a pair of polypus forceps is guided along the floor of the nose until the growth can be seized between the blades so as to tear it from its attachment and pull it out through the anterior nares.
After-treatment. The bleeding will generally cease spontaneously, assisted by cold ablutions to the face, or pinching the end of the nose until a clot forms (see [p. 575]). If bleeding persists, a piece of gauze, moistened with peroxide of hydrogen, should be packed in lightly and removed as soon as the patient can lie down quietly. It is best to avoid the use of any plug. It was to plugging that Luc attributed the loss of a patient from meningitis consequent on the removal of polypus.[63]