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Medical
Technologies
Overview and a Brief History
Medical Technology is…
 One component of the broader field of Health
Technology which includes:
Health-care products, equipment, tools, and
medicines that are used to prevent, diagnose,
monitor, and treat various conditions or illnesses
 Engineers continuously strive to develop new
technological devices that:
Improve quality of health care
Provide a more accurate diagnosis
Detect problems earlier
Are non-invasive (no incision)
Decrease the recovery time/rehabilitation period
Health Technology
 In 1900: -average life expectancy for a human in
the United States was 47 years
 In 2000: -average life expectancy was nearing
77 years
 This increase of 30 years was a result of several
factors including:
 Creation of a safe water supply
 Wide assortment of medical advances in:
• diagnosis
• pharmaceuticals
• medical devices
• various other forms of treatment
A little bit of history…
 In the early beginnings of humankind, disease
was viewed with mystery
Caused by negative interaction between environmental
elements and body fluids
 Hippocrates (460-377 BC) and Claudius Galen
(131-201 AD) described the four humours
Measured deficiency or excess of body fluids with
respect to the changing seasons
**First documented Western physicians to actively engage
in the science of healing to increase the quality of life
for their patients**
A little bit of history…
Medical technology slowly evolved in
response to diseases with high mortality
rates (Black plague –Europe, 1348 and
1350)
Medicine and medical technology has become
the antidote for illness and disease that
formerly destroyed entire societies
The Evolution-Early Stages
 Patient descriptions of symptoms and personal
observations
 Rarely a physical examination of body
 Theoretical and philosophical approach
 Medical students discouraged from touching patient while
learning
 This started to change as physicians realized that
medical texts first published in 11th century and the
general practices of the time had many errors
 By the 18th century, manual techniques to diagnose
patients became more accepted as a medical practice
 Use of cadavers and physical touch (public was very reluctant)
The Evolution-Developing
 For the majority of the 19th century, general
practitioners provided in-home patient care
Decentralized and rural
 Most of the medical equipment that they used
fit easily into the doctor's “little black bag”
 In 1895, German physicist Wilhelm C.
Roentgen accidentally discovered a form of
electromagnetic radiation that could pass
through the body and leave an image of its
bones or organs on a photographic plate. The
birth of the X-ray sparked a revolution!
The Evolution-More Recent
 By the 19th century, physicians used machines
for diagnosis or therapeutics instead of instinct
Hutchison’s device for measuring vital capacity of the
lungs was one of the first technologies to numerically
measure an essential body function
Herisson’s sphygmomanometer for blood pressure
measurement was also an early device
 Slow change from the use of subjective evidence
provided by the patient, to objective evidence
obtained by mechanical and chemical technology
devices
The Evolution-Modern
 Diagnostic tools such as the electrocardiograph, CAT
scan, and MRI followed, as did the development of
artificial and transplanted organs and joints, as well
as other surgical devices and techniques designed to
keep the body functioning.
 These advancements and the discovery of antibiotics
and other life-saving drugs contributed to increasing
the life span of people throughout the developed
world—on average nearly 30 years longer than their
ancestors a century ago.
National Academy of Engineering, 2009
A Timeline…
1903
First Electrocardiograph Machine (ECG)
-After attaching electrodes to both arms and the
left leg of his patient, Dutch physician and
physiologist Willem Einthoven was able to record
the heart’s wave patterns on a
photographic plate or paper by
measuring small changes in electric
potential as the heart contracts
and relaxes
A Timeline…
1927
First Modern Practical Respirator
-Created using an iron box and two vacuum cleaners
-Dubbed the “iron lung”, the finished product—
nearly the length of a small car—encloses the
entire bodies of its first users: polio sufferers
with chest paralysis.
-Pumps raise and lower the pressure within the
respirator’s chamber, exerting a pull-push motion
on the patients’ chests. Only their heads
protrude from the huge cylindrical steel
drum.
National Academy of Engineering, 2009
A Timeline…
1930s
Artificial Pacemaker Invented
-Invented by Albert S. Hyman, a practitioner
cardiologist in New York City, to resuscitate
patients whose hearts have stopped
-Working with his brother he constructs a handcranked apparatus with a spring motor that turns a
magnet to supply an electrical impulse.
-His invention never receives
acceptance from the medical
community
National Academy of Engineering, 2009
A Timeline…
1933
Kouwenhoven Electric Shock “Defibrillator”
-Working on rats and dogs, William B. Kouwenhoven
and Orthello Langworthy discover that while a lowvoltage shock can cause ventricular fibrillation, or
arrhythmia, a second surge of electricity, or
countershock, can restore the heart’s
normal rhythm and contraction
-Kouwenhoven’s research in electric shock
and his study of the effects of electricity
on the heart lead to the development of the
closed-chest electric defibrillator and the
technique of external cardiac massage
today known as cardiopulmonary
resuscitation, or CPR
National Academy of Engineering, 2009
A Timeline…
1945
First Kidney Dialysis Machine
-Willem J. Kolff successfully treats a dying patient
with an "artificial kidney"
-Made of wooden drums, cellophane tubing, and
laundry tubs and is able to draw the woman’s blood,
clean it of impurities, and pump it back into her
body
-Kolff’s invention is the product of many years’
work, and the patient was his first long-term
success after 15 failures. In the course of his work
with the artificial kidney, Kolff notices that blue,
oxygen-poor blood passing through the artificial
kidney becomes red, or oxygen-rich, leading to
later work on a membrane oxygenator
National Academy of Engineering, 2009
A Timeline…
1948
First “Corneal” Contact Lens Developed
-Kevin Touhy receives a patent for a plastic
contact lens designed to cover only the eye's
cornea (instead of across all of the visible ocular
surface, 1636)
-Two years later George Butterfield introduces a
lens that is molded to fit the cornea's contours
rather than lie flat atop it
National Academy of Engineering, 2009
A Timeline…
1950s
First Artificial Hip Replacement
-English surgeon John Charnley applies engineering
principles to orthopedics and develops the first
artificial hip replacement procedure, or
arthroplasty
-In 1962 he devises a low-friction, high-density
polythene suitable for artificial hip joints and
pioneers the use of methyl methacrylate cement
for holding the metal prosthesis, or implant, to the
shaft of the femur
-Charnley's principles are then adopted for other
joint replacements, including the knee and shoulder
National Academy of Engineering, 2009
A Timeline…
1951
Artificial Heart Valve Developed
-Charles Hufnagel develops an artificial heart valve
and performs the first artificial valve implantation
surgery in a human patient
-The valve--a methacrylate ball in a methacrylate
aortic-size tube does not replace the leaky valve,
but acts as an auxiliary
-Albert Starr, working with electrical engineer
Lowell Edwards, designs a silicone ball inside a cage.
The Starr-Edwards heart valve is born and is still
in use today.
National Academy of Engineering, 2009
A Timeline…
1952
First Successful Cardiac Pacemaker
-Paul M. Zoll develops the first successful cardiac
pacemaker
-The bulky device, worn externally on the patient’s
belt, plugs into an electric wall socket and
stimulates the heart through two metal electrodes
placed on the patient’s bare chest
National Academy of Engineering, 2009
A Timeline…
1953
First Successful Open-heart Bypass Surgery
-John H. Gibbon performs the first successful
open-heart bypass surgery on an 18-year-old whose
heart and lung functions are supported by a heartlung machine developed by Gibbon
-The device is the culmination of two decades of
research and experimentation and heralds a new
era in surgery and medicine
-Today coronary bypass surgery is one of the most
common operations performed
National Academy of Engineering, 2009
A Timeline…
1954
First Human Kidney Transplant
-Led by Joseph E. Murray, physicians remove a
healthy kidney from the donor and implant it in his
identical twin brother, who is dying of renal
disease
-Since the donor and recipient are perfectly
matched, the operation proves that in the absence
of the body’s rejection response, which is
stimulated by foreign tissue, human organ
transplants can succeed
National Academy of Engineering, 2009
A Timeline…
1960
First Totally Internal Pacemaker
-Buffalo, New York, electrical engineer Wilson
Greatbatch develops the first totally internal
pacemaker using two commercial silicon transistors
-Surgeon William Chardack
implants the device into 10 fatally
ill patients. The first lives
for 18 months, another for
30 years
A Timeline…
1963
Laser Treatments to Prevent Blindness
-Francis L’Esperance works with a ruby laser photocoagulator to treat diabetic retinopathy, a
complication of diabetes and a leading cause of
blindness in the United States
-In 1965 he begins working to design an argon laser
for eye surgery (the blue-green light of the argon
laser is more readily absorbed by blood vessels than
the red light of the ruby laser)
-In early 1968, after further refinements and
careful experiments, the argon-ion laser is used to
treat patients with diabetic retinopathy
National Academy of Engineering, 2009
A Timeline…
1970s
Arthroscope Introduced
-Advances in fiber-optics technology give surgeons a
view into joints and other surgical sites through an
arthroscope, an instrument the diameter of a pencil,
containing a small lens and light system, with a video
camera at the outer end
-Used initially as a diagnostic tool prior to open
surgery, arthroscopic surgery, with its minimal
incisions and generally shorter recovery time, is
soon widely used to treat a variety of joint problems
National Academy of Engineering, 2009
A Timeline…
1971
First Soft Contact Lens
-Bausch & Lomb licenses Softlens, the first soft
contact lens approved by the FDA
-The new product is the result of years of research
by Czech scientists Otto Wichterle and Drahoslav
Lim and is based on their earlier invention of a
"hydrophilic" gel, a polymer material that is
compatible with living tissue and therefore suitable
for eye implants
-Soft contacts allow more oxygen to reach the
eye’s cornea than do hard plastic lenses
National Academy of Engineering, 2009
A Timeline…
1972
CAT or CT scan is introduced
-Computerized axial tomography, popularly known as
CAT or CT scan, is introduced as the most important
development in medical filming since the X ray some
75 years earlier
-With the help of a computer, the device combines
many x-ray images to generate cross-sectional views
as well as three-dimensional images of internal
organs and structures
-Used to guide the placement of instruments or
treatments, CAT eventually becomes the primary
tool for diagnosing brain and spinal disorders
National Academy of Engineering, 2009
A Timeline…
1978
First Cochlear Implant Surgery
-Graeme Clarke in Australia carries out the first
cochlear implant surgery
-Advances in integrated circuit technology enable
him to design a multiple electrode receiverstimulator unit about the size of a quarter
A Timeline…
1980s
Controlled Drug Delivery Technology Developed
-Robert Langer develops the foundation of today’s
controlled drug delivery technology
-Using pellets of degradable and non-degradable
polymers he fashions a porous structure that allows
slow diffusion of large molecules
-Such structures are turned into dime-size
chemotherapy wafers to treat brain cancer after
surgery. When placed at the site where a tumor has
been removed, the wafer slowly releases powerful
drugs to kill any remaining cancer cells. By confining
the drug to the tumor site, the wafer minimizes toxic
effects on other organs
National Academy of Engineering, 2009
A Timeline…
1981
MRI (magnetic resonance imaging) Scanner
Introduced
-The first commercial MRI (magnetic resonance
imaging) scanner arrives on the medical market
-Using high-speed computers, magnetic resonance
imaging (MRI) is adapted for medical purposes,
offering better discrimination of soft tissue than xray CAT and is now widely used for noninvasive
imaging throughout the body
National Academy of Engineering, 2009
A Timeline…
1982
First Permanent Artificial Heart Implant
-The first permanent artificial heart, a silicone and
rubber device is received by a Seattle dentist
-The dentist survives for 112
days with his pneumatically
driven heart (operated with
compressed air)
National Academy of Engineering, 2009
A Timeline…
1985
Implantable Cardioverter Defibrillator (ICD)
Approved
-The FDA approves Michel Mirowski’s implantable
cardioverter defibrillator (ICD), an electronic
device to monitor and correct abnormal heart
rhythms, and specifies that patients must have
survived two cardiac arrests to qualify for ICD
implantation
-It weighs 9 ounces and is roughly the size of a deck
of cards
National Academy of Engineering, 2009
A Timeline…
1987
Deep-brain Electrical Stimulation System
-France’s Alim-Louis Benabid a neurosurgeon
implants a deep-brain electrical stimulation system
into a patient with advanced Parkinson’s disease
-The experimental treatment is also
used for dystonia, a debilitating
disorder that causes involuntary and
painful muscle contractions and
spasms, and is given when oral
medications fail
National Academy of Engineering, 2009
A Timeline…
1987
First Laser Surgery on a Human Cornea
-New York City ophthalmologist Steven Trokel
performs the first laser surgery on a human cornea,
after perfecting his technique on a cow’s eye
-Nine years later the first computerized laser—
Lasik—designed to correct the refractive error
myopia, is approved for use in the United States
A Timeline…
1990
Human Genome Project
-Researchers begin the Human Genome Project, with
the goal of identifying all of the approximately
30,000 genes in human DNA and determining the
sequences of the three billion chemical base pairs
that make up human DNA
-The project catalyzes the multibillion-dollar U.S.
biotechnology industry and fosters the development
of new medical applications, including finding genes
associated with genetic conditions such as familial
breast cancer and inherited colon cancer
-A working draft of the genome is announced in
June 2000
National Academy of Engineering, 2009
The Evolution
 Medical technology stimulated the growth of medical
specialists
 In 1930, only 1/4 practitioners was a medical specialist
 By 1980, more than 4/5 practitioners were specialists
 Specialization was a result of:
1. Patient populations concentrated in urban centers
2. Economic incentives for doctors to relocate
3. General practitioners (GP) wanted to escape irregular hours
4. Specialization seemed to hold more prestige
5. GPs could no longer keep up with the amount of knowledge
required to make accurate diagnostic and treatment
assessments (increases in technology)
6. Machinery and equipment used in medicine became complex and
required specialized technical expertise and support
The Evolution
 With more specialists, came a need for more cooperative
arrangements since no single physician possessed all of the
special knowledge required
 Increase in the number of physicians associated with private medical
groups
 Introduction of hospitals
 Medical services became cooperative practice arrangements
 Decreasing level of local medical services in many rural areas
 Medical technology and specialization increased the amount
of data required to diagnose and treat
 Development of the medical record to organize and store data
 Need for medical technicians and data specialists
 By 1969, 80% of those employed as medical professionals were nonphysicians
The Evolution
 The exponential growth in medical technology and data
created the need for more technicians of all kinds to test
and manage data
 Education was needed for medical technicians for increased
proficiency in the use of technology
 Patients also needed education to be better informed about
the confusing decisions regarding the tests and procedures
being performed for their health and well-being
Something to think about…
Most of us have encountered some kind of medical
technology in our lives. Even if we have not
experienced it ourselves,
someone we know probably has.
If you have ever broken a bone, you have probably had
an X-ray taken. If someone in your family has had
kidney problems, he or she might have had to go on
dialysis. Perhaps you know someone who has been
through organ transplant surgery, heart surgery, or
fertility treatment.
There are many kinds of technology that help medical
professionals diagnose and treat health problems.
Wait a minute…consider this!
“Medical technology has embedded itself in our culture
and has been a positive and powerful force in the
improvement of life for millions of people.
However, for every yin there is a yang, and with all
things that are positive, there is also a negative
component that must not be ignored.
Most Americans are familiar with the benefits of
technology, specifically medical technologies; the
media reports on these benefits every day. However,
it is not often that physicians and patients have the
opportunity to discuss what has been given up, lost or
sacrificed as a result of using these same
technologies.”
R. L. Sanders : Medical Technology: A Critical Perspective . The
Internet Journal of Medical Technology. 2004 Volume 2 Number 1
Think/Pair/Share
1.
Write a list of medical technologies that
you, or people you know, have experienced.
2. Describe each technology and what it does
in as much detail as possible. If possible,
describe how you or the person you know
felt during the procedure.
3. Did you/they have positive or negative
feelings about the technology?
Think/Pair/Share
1.
Share your list of medical technologies with a partner.
2.
Discuss your feelings about the technologies. Do any of
them have ethical implications?
3.
Have the technologies made a difference to human lifespan and quality of life? Explain.
4.
From your perspective, which are the top 5 most
significant technologies? Provide reasoning for your
choices.
Blogging Response #2: Due Friday, October 18th
What are the top 3 most significant technologies? Provide
reasoning for your choices.