Major Advances in Bioengineering
 Artificial
Joints
 In
1994, a National Institutes of Health Consensus Panel declared that
total hip replacement is one of the most successful surgical procedures,
providing immediate and substantial improvement in a patient's pain,
mobility, and quality of life. More than 168,000 total hip replacements
are performed each year in the United States, according to the American
Academy of Orthopaedic Surgeons. THR involves removing diseased or
damaged bone in the upper end of the thigh bone (femur) and the section
of the lower pelvis into which the femur fits. The bone is then replaced
with a prosthesis, usually made of a metal alloy or polyethelene
(plastic) components. Successful replacement of deteriorated, arthritic,
and severely injured hips has contributed to enhanced mobility and
comfortable, independent living for many people who would otherwise be
substantially disabled.
Magnetic
Resonance Imaging (MRI)
 In
1952, the Nobel Prize in Physics was awarded for the discovery of
nuclear magnetic resonance, which laid the groundwork for one of the
most unique and important inventions in medical imaging since the
discovery of the X-ray. Magnetic resonance imaging (MRI) is a method of
looking inside the body without using surgery, harmful dyes or
radiation. The method uses magnetism and radio waves to produce clear
pictures of the human anatomy. Although MRI is used for medical
diagnosis, it uses a physics phenomenon discovered in the 1930s in which
magnetic fields and radio waves, both harmless to humans, cause atoms to
give off tiny radio signals. It wasn't until 1970, however, that Raymond
Damadian, a medical doctor and research scientist, discovered the basis
for using magnetic resonance as a tool for medical diagnosis when he
found that different kinds of animal tissue emit response signals of
differing length. He also discovered differences in response signals
between cancerous and non-cancerous tissue, and among the response times
of other kinds of diseased tissue.
Heart
Pacemaker
 The
invention and development of the heart pacemaker illustrates the merging
of medicine and engineering. The device is a result of the collective
efforts and collaboration of people and organizations from both
engineering and medicine, and both public and private institutions. The
pacemaker was the first electronic device ever surgically implanted
inside a human. First developed in the 1960s, pacemaker typically refers
to a small, battery-powered device that helps the heart beat in a
regular rhythm. Small electrical charges travel to one or multiple
electrodes placed next to the heart muscle. Originally pacemakers sent
one steady beat to the heart through a single electrode. Today's
pacemakers can sense when a heart needs help and delivers just the right
amount and duration of impulse---sometimes through multiple
electrodes---that maintain steady heart rate, even during physical
activity. While most pacemakers today are permanent implants, some are
used as temporary therapy for recovering heart patients.
Arthroscopy
 Arthroscopy is a
surgical procedure orthopedic surgeons use to visualize, diagnose and
treat problems inside a joint.
The
word arthroscopy comes from two Greek words, "arthro" (joint) and "skopein"
(look), and literally means "to look within the joint." In an
arthroscopic examination, an orthopedic surgeon makes a small incision
in the patient's skin and then inserts pencil-sized instruments that
contain a small lens and lighting system to magnify and illuminate the
structures inside the joint. Light is transmitted through fiber optics
to the end of the arthroscope that is inserted into the joint. By
attaching the arthroscope to a miniature television camera, the surgeon
is able to see the interior of the joint through this very small
incision. The camera attached to the arthroscope displays the image of
the joint on a television screen, allowing the surgeon to look, for
example, throughout the knee -- at cartilage and ligaments, and under
the kneecap. The surgeon can determine the amount or type of injury, and
then repair or correct the problem, if necessary.
Angioplasty
In 1977 in Zurich,
Switzerland, a young German physician named Andreas Gruentzig inserted a
catheter into a patient's coronary artery and inflated a tiny balloon,
opening a blockage and restoring blood flow to a human heart. Today more
than 1 million coronary angioplasties are performed each year worldwide,
making it the most common medical intervention in the world. Although
this procedure was first envisioned as simply an alternative to open
heart bypass surgery in only a handful of patients, today angioplasty
accounts for more than half of the treatments for coronary artery
disease. Biomedical engineering and advances in technology have not only
optimized basic balloon angioplasty, but also added the use of stents,
lasers and other interventional devices that restore normal blood flow
while minimizing damage to the heart muscle.
Bioengineered
Skin
 The
burgeoning field of tissue engineering promises to be one of the most
significant biomedical areas of the new century. The hope is that,
eventually, whole organs could be manufactured to replace those that are
injured or diseased. The field's first contribution to health care took
a big step toward fulfilling these promises by producing artificial
version of the body's largest organ, skin. Skin is a difficult organ to
transplant because of its inherently strong immune defense system.
Nevertheless, it has a relatively simple structure, making it a good
testing ground for the talents of tissue engineers. Patients can have
skin made to order that combines collagen as a binder with living human
cells. This is placed onto a wound, usually a chronic ulcer or a burn,
and its cells become activated and gradually integrate with those of the
patient.
Kidney
Dialysis
 In
the United States, one in 16 people, or about 17 million, are at risk
for kidney disease. More than 300,000 Americans currently live with
chronic kidney failure resulting from disease, birth defect or injury.
Virtually all these patients would die if not for the aid of ongoing
kidney dialysis. Kidney dialysis artificially filters and removes waste
products and excess water from blood, a process normally performed by
the kidneys. Although often referred to as an artificial kidney, kidney
dialysis is not a cure. The procedure can, however, give damaged kidneys
a rest and a chance to recover normal function, or be used until the
patient receives a transplant. For many patients, kidney dialysis is a
way of life. Kidney dialysis was first developed by a Dutch physician,
Willem Kolff, M.D., Ph.D. In the early 1940s, he began searching for a
way to use dialysis, the process by which particles pass through a
membrane, to treat patients with kidney failure. A sever shortage of
materials due to the war forced Kolff to improvise, especially when it
came to a suitable membrane, the key component to the filtering process.
Now, as the number of dialysis patients continues to grow at a rate of
about 7 percent annually, and because costs for dialysis care are
already more than $11 billion in the United States alone, research to
find more efficient, low-cost methods of treatment remains a priority
for biomedical engineers. Current efforts include not only improving the
components of dialysis, such as better dialysates and membranes, but
also developing alternatives to dialysis, such as a true artificial
kidney, xenotransplantation, and replacement kidneys through tissue
engineering.
Heart-lung
Machine
 One
of the truly revolutionary pieces of medical equipment has been the
invention and development of the heart-lung machine. Before its
introduction to medicine in the 1950s, heart surgery was unheard of;
there was no way to keep a patient alive while working on the heart.
Today, about 750,000 open-heart procedures are performed each year.
During an open-heart surgery, such as bypass surgery, the heart-lung
machine takes over the functions of the heart and lungs and allows a
surgeon to carefully stop the heart while the rest of the patient's body
continues to receive oxygen-rich blood. The surgeon can then perform
delicate work on the heart without interference from bleeding or the
heart's pumping motion. Once the procedure is over, the surgeon restarts
the heart and disconnects the heart-lung machine.
Note: Some resources in this section are provided by the US Department
of Labor, Bureau of Labor Statistics
and the Whitaker Foundation.
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