The techniques of microsurgery are revolutionizing the operating theatre.
The surgeon uses a microscope to view the inside of the body and can perform
operations on tiny structures like nerves and blood vessels.
Microsurgery is a special technique used for any operation that involves
minute, delicate or difficult to get at parts of the body. The ability to
stitch together blood vessels with a diameter of just 2mm (0.04in) has
revolutionized surgery and the techniques are used in a whole range of
different operations. These include transplant surgery, plastic and
reconstructive surgery for victims of severe accidents and burns, and eye
surgery to implant a new lens or cornea.
Surgeons can unblock the
Fallopian tubes in women who are infertile, reverse vasectomy, move sections
of skin and muscle from one part of the body to another to fill defects left
by injuries or burns, replace diseased bones in the middle ear, or treat
deafness, restore severed fingers, toes, hands, even penises.
The very first microsurgical techniques were described as long ago as the
16th century by early surgeons operating on arteries, but they didn't become
commonplace until as late as this century with the breakthrough development
of the operating microscope.
In 1903, a vetinary surgeon named Hoephner described limb replantation in
dogs. With the purification of the anticoagulant drug heparin, used to
prevent blood clotting, the way was open for surgeons to rejoin blood
vessels without the risk of dangerous clotting. At first, however, surgeons
could only operate on large blood vessels, because fine stitching materials
and delicate instruments had not been developed.
The introduction of the operating microscope to hospitals in the 1920s
revolutionized every type of surgery, and the first microsurgical operations
were performed on the middle ear. By the 1950s, surgeons were experimenting
with the same technique in eye surgery.
In 1958, surgeons performed the first operation to replant a leg, that of
a Japanese girl, which had been amputated when she was run over by a train.
The following year, another surgeon performed the first operation to unblock
an infertile woman's Fallopian tubes using microsurgical techniques.
By the late 1960s, surgeons were regularly replanting severed limbs, and
digits, and were working on rejoining nerves as well as blood vessels. In
the 1970s, new organ transplants, such as those for heart and lungs, were
Another breakthrough came when surgeons learned to perform a living bone
graft, succeeding in tranplanting bones complete with their blood vessels.
Urologists also started using microsurgery for operations on babies and
children with abnormalities of the urinary system, and vasectomy reversals
began to be performed. The same techniques enabled surgeons to reconstruct
the breasts of women who had had mastectomies due to breast cancer.
Today, the techniques of microsurgery are fully developed, and surgeons are
developing even more sophisticated techniques of organ transplantation. As
the problem of the body rejecting foreign tissue is solved with the
development of ever more safe and effective drugs to suppress the immune
system, microsurgery will have an even more brilliant future in the field of
composite tissue and organ transplantations.
The needles, scissors and scalpels that are used to perform microsurgery
are small and delicate as are the forceps used to grasp them. The stitches
used are as fine as a human hair. The small instruments and the delicate
nature of the operations involved means that microsurgical operations have
to be performed painstakingly slowly with the aid of an operating microscope
to enable the surgeon to view the organs he is operating on. This microscope
is fixed on a stand, which is moved up and down by means of foot pedals,
leaving both the surgeon's hands free to perform the operation.
Not everyone is suitable for
microsurgery. Age, occupation and the degree of injury has to be assessed.
In children and young people, there is a greater degree of success. The most
suitable type of injury for a rejoin operation is where there has been a
clean cut or mild crushing injury.
In cases where there has been severe crushing, there is usually too much
damage to nerves and blood vessels over a wide area and the risk of clotting
is greater. Thumb replantation is one of the most successful operations,
especially in children over five.
Afterwards, patients sometimes report extreme sensitivity to cold, though
this usually improves slightly with time. Naturally, the limb or digit is
not usually as strong as it was before. Secondary surgery on tendons and
joints is sometimes needed to ease any stiffness and help improve function.
For the best chance of success,
replantation has to take place within as short a period of time after
amputation as possible. For fingers, six hours is usually the maximum,
though if they are cooled, they can be kept for longer. After a day,
however, there will be irreversible damage to the blood vessels.
In the case of whole limbs, the time they can be kept is much shorter as
there are large amounts of muscle which become damaged through lack of
Other types of surgery that have been made possible by new microsurgery
techniques include thick skin or muscle grafts, arteriole bypass operations
within the brain, bringing down undescended testicles, grafting nerves to
restore normal appearance of cases of facial palsy (paralysis), grafting
toes onto the hand to replace lost fingers and thumb, and operating on the
lymph vessels for the relief of lymphoedema -- the abnormal accumulation of
lymph which causes swelling of limbs, often as a result of cancer.
Microsurgical techniques have also transformed the treatment of skin
defects, especially where the bone is exposed. In a conventional skin graft,
a thin layer of skin is taken from one part of the body and transferred to
the affected area. However, this technique is not suitable for all types of
NEW SKIN GRAFTS
In the past, skin with underlying
tissue was moved by a complex series of operations to ensure it was never
without a blood supply. The skin flap technique of microsurgery enables a
segment of skin to be isolated, together with its artery, vein and nerve,
and the whole segment can be stitched to a new supply at the site of the
These techniques have brought some amazing successes, such as the surgeon
who lost all four fingers of his hand when it was crushed in the 1985 Mexico
City earthquake. After having two toes plus a flap of skin from his arm
transplanted to his palm, he complete his training and is now a plastic
Microsurgery can also enable surgeons to bypass blocked arteries in the
brain after an attack of thrombosis by moving a neighbouring artery over and
joining it to an artery beyond the one that is blocked.
Before an operation, a
transfusion is given to correct any blood loss if necessary, after which the
patient is given antibiotics, and X-rays are taken to assess the amount of
damage. The amputated part is taken to the operating theatre where it is
cleaned and key structures, such as arteries, veins, nerves and tendons are
identified under the microscope. The amputated part is then rejoined, little
by little, in a slow process.
After the operation, anticoagulant drugs are given to prevent blood
clots, which may form due to slight narrowing of the artery and loss of the
smooth lining at the join as a result of scar tissue. It will be obvious
within a couple of weeks whether the re-attached part is going to survive.
MAKING A RECOVERY
It is usually several months
before the full success of the operation can be gauged in terms of
restoration of normal function. Some patients regain movement and sensation
and are able to return to work in a matter of months.
Others have to endure months or years of swelling, stiffness and pain.
About half of all patients need more surgery to help them achieve the best
possible function. However, future refinements in a technique may make this