Word: cannula
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Called cryosurgery, from the Greek kryos (cold or frost), the new method actually involves neither ice nor scalpel. The surgeon inserts a thin cannula (tube) that kills offending tissue with liquid nitrogen's intense cold (- 196° C., or 321° below zero F.). Usually no tissue is actually removed, and the body's natural clean-up system removes the debris. Virtually bloodless and almost painless, cryosurgery can be done on patients who remain fully conscious or only lightly anesthetized. In some cases cryosurgery is used only to relieve symptoms, but in others it achieves actual cures. Among...
...U.C.L.A. go in through the nasal passages and the sphenoid bone that lies behind them. First, the patient's head is clamped in a stereotactic device that enables the surgeons to take bearings in three dimensions. Then the surgeons saw through the intervening bone and insert the ultracold cannula. Dr. Rand found that temperatures as low as -70° C. maintained for as long as 17 minutes had no appreciable effect on the stubbornly resistant pituitary. So he dropped the temperature inside the gland to between -170° C. and -190° C. With a probe-or sometimes with...
...UTERUS. In many cases of excessive bleeding from the endometrium (lining of the uterus) caused by tumors, application of ultracold through a larger cannula for two to ten minutes will usually destroy the tumors and thus make a hysterectomy unnecessary, reports Dr. Cahan. He also suggests using cryosurgery instead of "tying off the tubes" to sterilize women who, for medical reasons, must have no more children. The procedure takes two minutes...
...carefully calculated spot on his head. Dr. Cooper then makes an incision and bores a hole in the patient's skull. He places a bow-shaped instrument of his own design around the patient's head, and using the instrument as a guide, carefully threads a long cannula (tube) toward the thalamus at the center of the brain...
...rays help Dr. Cooper in locating the spot that he wants to freeze in the thalamus. But to make sure that his cannula is on target, he conducts a simple test. A small amount of liquid nitrogen is pumped to the cannula tip to cool the thalamus. Dr. Cooper asks the patient to raise his hand. If the hand stops shaking, Dr. Cooper is assured that his cannula is properly placed; more liquid nitrogen is pumped through the cannula to destroy permanently a larger area in the thalamus. Thus far, Dr. Cooper has used his technique on 1,000 patients...