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- Medicine: "Microsurgery: Sew Small" Uploaded: March 1, 1987
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- A 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 long
- hours of painstaking work in microsurgery. In the operating
- room , the surgeon doesn't stand, but sits in a chair that
- supports her body. Her arm is cradled by a pillow. Scalpels
- are present as are other standard surgical tools, but the
- suture threads are almost invisible, the needle thinner than
- a human hair. And all the surgical activity revolves around
- the most important instument, the microscope.
-
- The surgeon will spend the next few hours looking through
- the microscope at broken blood vessels and nerves and sewing
- them back together again. The needles are so thin that they
- have to be held with needlenosed jeweller's forceps and will
- sew together nerves that are as wide as the thickness of a
- penny. To make such a stitch, the surgeon's hands will move
- no more than the width of the folded side of a piece of
- paper seen end on!
-
- Imagine trying to sew two pieces of spaghetti together and
- you'll have some idea of what microsurgery involves.
-
- Twenty-five years ago, this man's thumb would have been
- lost. But in the 1960s, surgeon's began using microscopes
- to sew what previously had been almost invisible blood
- vessels and nerves in limbs. Their sewing technique had been
- developed on large blood vessels over a half century earlier
- but could not be used in microsurgery until the needles and
- sutures became small enough. The surgical technique, still
- widely used today, had taken the frustrating unreliability
- out of sewing slippery, round-ended blood vessels by
- ingeniously turning them into triangles. To do this, a cut
- end of a blood vessel was stitched at three equidistant
- points and pulled slightly apart to give an anchored,
- triangular shape. This now lent itself to easier, more
- dependable stitching and paved the way for microsurgery where
- as many as twenty stitches will have to be made in a blood
- vessel three millimetres thick. The needle used for this can
- be just 70 millimetres wide, only ten times the width of a
- human blood cell.
-
- All this technology is focused on getting body parts back
- together again successfully. The more blood vessels
- reattached, the better the survival chances for a toe or a
- finger. The finer the nerve resection, the better the
- feeling in a damaged part of the face, or control in a
- previously useless arm. But the wounded and severed body part
- must be treated carefully. If a small part of the body, such
- as a finger is cut off, instead of torn, wrapped in a clean
- covering, put on ice and then reattached within a few hours,
- the chance of success is over ninety percent, as long as one
- good 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 smashed
- beyond repair. But in the past 14 years, you would have been
- in luck, if your feet were intact. Every year in North
- America, hundreds of big toes are removed from feet and
- grafted onto hands. Sometimes tendons are shifted from less
- important neighbouring fingers to allow the thumb to work
- better in its unique role of opposing the other fingers and
- allowing us to grip.
-
- While we in North America can live without our big toes and
- never really miss them, people in Japan can't. They need
- their big toes to keep the common footwear, the clog, on
- their feet. So their second toe is taken instead.
-
- Farmers, labourers car accident victims and home handymen
- are the people most often helped by microsurgery replants.
- And because blood vessels are being reattached, burn victims
- can now benefit. Flaps of their healthy skin are laboriously
- reattached 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 have
- them reopened microsurgically. When a cancerous esophagus
- must be removed, it can be replaced using a section of the
- person's own bowel. These people can then lead a more normal
- life, using their mouth to eat with instead of inserting
- food though a feeding tube in their stomach.
-
- Doctors have been able to rebuild an entire lower face by
- sculpting the lower jaw from living hip bone and covering it
- with the skin from that piece of bone. In all, over seventy
- parts of your body can be used as donor backups and recycled
- into other damaged sites. And because your body won't reject
- your own tissue - a constant hazard in transplants - in this
- case, you are your own best friend.
-
- In everyday use, however, microsurgery is proving to be a
- miracle worker, large and small. We take for granted, for
- instance, all the complex nerve and muscle control that goes
- into a simple a gesture as smiling. But one young woman
- couldn't. An accident left her with a face that was damaged
- and unable to smile. Microsurgery reconnected severed nerves,
- giving muscle control back to her face, restoring her looks
- and giving her something to smile about.
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