Реферат: Microsurgery Essay Research Paper Microsurgery Sew SmallA
Название: Microsurgery Essay Research Paper Microsurgery Sew SmallA Раздел: Топики по английскому языку Тип: реферат |
Microsurgery Essay, Research Paper Microsurgery: Sew SmallA man came into the emergency ward at one o’clock.His thumb came in an hour later.The surgeon’s job: get them back together. The successful re-attaching of fingers to hand requires longhours of painstaking work in microsurgery. In the operatingroom , the surgeon doesn’t stand, but sits in a chair thatsupports her body. Her arm is cradled by a pillow. Scalpelsare present as are other standard surgical tools, but thesuture threads are almost invisible, the needle thinner thana human hair. And all the surgical activity revolves aroundthe most important instument, the microscope. The surgeon will spend the next few hours looking throughthe microscope at broken blood vessels and nerves and sewingthem back together again. The needles are so thin that theyhave to be held with needlenosed jeweller’s forceps and willsew together nerves that are as wide as the thickness of apenny. To make such a stitch, the surgeon’s hands will moveno more than the width of the folded side of a piece ofpaper seen end on!Imagine trying to sew two pieces of spaghetti together andyou’ll have some idea of what microsurgery involves.Twenty-five years ago, this man’s thumb would have beenlost. But in the 1960s, surgeon’s began using microscopesto sew what previously had been almost invisible bloodvessels and nerves in limbs. Their sewing technique had beendeveloped on large blood vessels over a half century earlierbut could not be used in microsurgery until the needles andsutures became small enough. The surgical technique, stillwidely used today, had taken the frustrating unreliabilityout of sewing slippery, round-ended blood vessels byingeniously turning them into triangles. To do this, a cutend of a blood vessel was stitched at three equidistantpoints and pulled slightly apart to give an anchored,triangular shape. This now lent itself to easier, moredependable stitching and paved the way for microsurgery whereas many as twenty stitches will have to be made in a bloodvessel three millimetres thick. The needle used for this canbe just 70 millimetres wide, only ten times the width of ahuman blood cell. All this technology is focused on getting body parts backtogether again successfully. The more blood vesselsreattached, the better the survival chances for a toe or afinger. The finer the nerve resection, the better thefeeling in a damaged part of the face, or control in apreviously useless arm. But the wounded and severed body part must be treated carefully. If a small part of the body, suchas a finger is cut off, instead of torn, wrapped in a cleancovering, put on ice and then reattached within a few hours,the chance of success is over ninety percent, as long as onegood artery and one good vein can be reattached. Not only is micro surgery allowing body parts to be reattached,it’s also allowing them to be reshuffled. Before 1969,nothing could be done for you if you’d had your thumb smashedbeyond repair. But in the past 14 years, you would have beenin luck, if your feet were intact. Every year in NorthAmerica, hundreds of big toes are removed from feet andgrafted onto hands. Sometimes tendons are shifted from lessimportant neighbouring fingers to allow the thumb to workbetter in its unique role of opposing the other fingers andallowing us to grip.While we in North America can live without our big toes andnever really miss them, people in Japan can’t. They needtheir big toes to keep the common footwear, the clog, ontheir feet. So their second toe is taken instead. Farmers, labourers car accident victims and home handymenare the people most often helped by microsurgery replants.And because blood vessels are being reattached, burn victimscan now benefit. Flaps of their healthy skin are laboriouslyreattached more successfully, blood vessel by blood vessel,to increase chances that the graft will take. Some women,whose diseased Fallopian tubes have become blocked, can havethem reopened microsurgically. When a cancerous esophagusmust be removed, it can be replaced using a section of theperson’s own bowel. These people can then lead a more normallife, using their mouth to eat with instead of insertingfood though a feeding tube in their stomach. Doctors have been able to rebuild an entire lower face bysculpting the lower jaw from living hip bone and covering itwith the skin from that piece of bone. In all, over seventyparts of your body can be used as donor backups and recycledinto other damaged sites. And because your body won’t rejectyour own tissue – a constant hazard in transplants – in thiscase, you are your own best friend. In everyday use, however, microsurgery is proving to be amiracle worker, large and small. We take for granted, forinstance, all the complex nerve and muscle control that goesinto a simple a gesture as smiling. But one young womancouldn’t. An accident left her with a face that was damagedand unable to smile. Microsurgery reconnected severed nerves,giving muscle control back to her face, restoring her looksand giving her something to smile about. 320 |