Originally Published MDDI April 2005
MDEA 2005
Prescription for Award-Winning Design: Go to the Doctor
An award-winning medical device is one that is easy to use and promotes
error-free operation, bringing together all of the components needed to do a
particular task. In the Medical Design Excellence Awards competition, the
judges look for attributes such as easily visible displays and controls. The
judges also look for usability, human factors, and technical competence.
Moreover, a device must be "safe in the clinic, not just in the conference
room," says juror William A. Hyman, professor and interim head of the
department of biomedical engineering at Texas A&M University (College
Station, TX).
"Devices must show a clear benefit, preferably to both the patient and the
clinician," says juror Matthew B. Weinger, MD, professor of anesthesiology,
biomedical informatics, and medical education at Vanderbilt University
School of Medicine (Nashville, TN). In some cases, the benefit to the
user—usually a clinician—is the most significant aspect of a device and what
makes it stand out above the rest. The
following devices fell into that special group.
RelyX Luting Plus Cement Dispenser
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| The RelyX Luting Plus, manufactured by 3M ESPE Dental Products, is a clicker dispenser of flouride-releasing dental cement. |
The RelyX Luting Plus dispenser, manufactured by 3M ESPE Dental Products (St. Paul, MN), is a clicker dispenser of fluoride-releasing dental cement
for permanently affixing crowns and bridges. The clicker ensures a precise
1:1 volume ratio of the two-part cement.
"The cement is provided in a ratio of 1:1. That's an advantage because it's
a specific delivered dose," says juror Eliot Lazar, MD, principal of ElCon
Medical (Buffalo, NY). "The delivery device has been designed so that the
two sides are different, one allowing oxygen and one not allowing oxygen,
which makes it a convenient storage and delivery device for the cement at a
particular point in
time. That makes it very easy for the dental assistant," he explains.
The jurors noted that the dispenser is fast and efficient for the dental
assistant. The dispenser and cement are designed to replace a more
complicated, less accurate powder-liquid combination. "It allows the dentist
or dental assistant to easily get the amount required," says juror Jay R.
Goldberg, who serves as director of healthcare technologies at Marquette
University (Milwaukee). "This is important because if the proportions are
not right, a patient's crown could fall out prematurely," he says.
"Before we developed the Relyx luting cement, the dental assistant was
required to scoop out powder, place it on a pad, and drop liquid out of a
vial," explains Bruce Broyles, senior product development specialist for 3M.
"That is a fairly inaccurate way of dispensing a cement that needs a fairly
consistent viscosity when all is said and done," notes Broyles. "The
powder-liquid systems would provide such a wide range of viscosities that
the cement was either too thick or too thin. When applying it to a crown,
the dentist would often ask the dental assistant to remix it because it was
too far from a reasonable viscosity."
Achieving a consistent viscosity easily and accurately became the goal of
the design team. If the viscosity is too high, says Broyles, the dentist
can't force the crown down on the stump because the material won't flow out.
When it is curing, the crown will be sitting too high, and when the patient
bites down, the crown will hit the opposing teeth. A too-thin viscosity, he
says, results in too much resin, which can affect the mechanical and
physical properties of the material.
"We heard our customers, and we realized this was a problem," says Broyles.
"We came up with a paste-paste
version of this liquid-powder cement that we could dispense from an accurate
dispensing system." Broyles says the design team developed the clicker
dispenser system so that it would ensure an accurate ratio each time and be
easy for dental assistants to use.
The users had input in the design early on. Broyles says that each quarter,
3M brings in a large group of dental assistants and, twice a year, the
company brings in local dentists for their feedback. "We had a lot of input
on the design of the dispensing system from the dental assistants and the
dentists to help ensure that the cement is easy to use and fairly easy to
clean up," he says. "You get the 1:1 ratio each time, so that the physical
properties of the material are always right."
The company chose formulations that allow the two pastes to sit on the shelf
for up to two years without polymerizing. "Some thought was definitely given
to this aspect of the product, and it is clear that the necessary testing
was done to give it a sufficient shelf life. The designers clearly
appreciated that the shelf life was another important feature," says
Goldberg.
Intelect Advanced and Mobile Electrotherapy Range
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| The Intelect Advanced and Mobile Electrotherapy range, manufactured by Chattanooga Group, is used to administer physiotherapy treatments. |
The Intelect Advanced and Mobile Electrotherapy range, manufactured by
Chattanooga Group (Hixson, TN) is a fully integrated suite of clinical
electrotherapy equipment used to administer a wide selection of
physiotherapy treatments.
For clinical electrotherapy, all devices—such as ultrasound, vacuum
stimulator, and patient data system—come in a single unit for the therapist.
The jurors noted that the innovation of the device is its nice workstation
and applied state-of-the-art industrial design. "With multiple modalities in
one workstation, it creates task flow," says juror Goldberg.
Task flow, as it is known, was a critical element in the design," says Ed
Dunlay, vice president of marketing for the Chattanooga Group. "Our vision
of the product was of a modular design to allow clinicians to select the
modalities they use clinically from a single operating screen. At present,
we have six modalities that can be selected from one screen, and we are
working on additional modalities as well," he says.
"What stands out is that it has the devices all in one place," notes
Goldberg. "It has several modalities, whereas
before, the physiotherapist had to use six different pieces of equipment."
Dunlay says the company conducted extensive global surveys of clinicians in
the world of rehabilitation as to the value and benefit of integrating
multiple clinical modalities into one unit. "Those outcomes determined our
direction," he says.
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| The F.A.S.T., by Genesis Medical Interventional Inc., employs a funnel catheter and suction to remove blood clots from the access grafts of dialysis patients. |
The F.A.S.T. (facilitated aspiration/suction thrombectomy) device,
manufactured by Genesis Medical Interventional Inc. (Redwood City, CA),
employs a funnel catheter and suction to remove blood clots from the access
grafts of dialysis patients, reducing the possibility that clots might move
elsewhere in the body where they could cause death.
"The device brings together unique components literally in a kit so that you
have a consistent and logical methodology," says juror Hyman. "It is
presented as a whole, as opposed to standard methods that require the
surgeon to assemble the parts needed for the procedure," he says. "But to
determine what pieces are needed to effect the technique safely is as
critical as finding the pieces. The product also represents a technique, and
addresses both of those uses."
Hyman says it's the broad principles that contributed to the successful
design of the system. "It is not particularly easy to use because it's a
challenging technique," says Hyman. "In this case, the user benefit that was
created certainly leads to patient benefit."
"Developing the device was all about the team. It was their love of the
technology and their desire to increase patient safety," says William
Dubrul, CEO of Genesis.
The real clinician benefit, he says, is that the doctor is now "pulling the
clot out instead of sending it elsewhere in the body." Dubrul explains that
most physicians use lytic drugs, which can be dangerous for high-risk
dialysis patients. These patients are six times more likely than nondialysis
patients to have a pulmonary embolism, he says.
"Our device does not get rid of the clot faster. We are just allowing the
doctors to remove the clot instead of sending it downstream," says Dubrul.
The initial target for the device will be those physicians who are currently
using mechanical thrombectomy. The doctors who use lytic drugs are more
skeptical, he says. They want proof that the drugs do cause problems.
Genesis is planning side-by-side trials over the next couple of years to
address this issue.
"We are still addressing some ease-of-use issues as
well. The procedure is different, so training is going to take some time.
Physicians do love the idea of removing the clot," he says.
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| Axxess neurostimulation leads, manufactured by Advanced Neuromodulation Systems (ANS), are designed to provide surgeons with more options. |
Axxess neurostimulation leads, manufactured by Advanced Neuromodulation
Systems (ANS, Plano, TX), are designed to provide surgeons with better
control and more placement options, resulting in less-invasive insertion.
Used for pain electrostimulation (e.g., epilepsy), the leads are the
smallest-diameter electrodes available for surgery that is guided under
fluoroscopy (0.8 mm). The leads, which have a 1:1 torque ratio, have inner
guidewire bipolar leads that go through the tissue.
"When using neurostimulation to treat chronic pain, the primary goal is to
position leads (and ultimately, platinum conductors) over specific regions
of the epidural space in order to achieve effective coverage of the
patients' pain," explains Brad Maruca, marketing director for ANS. "However,
lead placement can be difficult because a large portion of patients have
scar tissue and adhesions, often as a result of prior surgery, which create
an impediment for physicians. While navigating leads into position around
such impediments, the technical challenge for physicians is to control the
distal tip of the lead through manipulation of the proximal end, which can
be 3060 cm away," he says. Maruca says that with its small size and 1:1
torque transfer, Axxess allows physicians to move the lead in precise, fine
movements, helping them place it into proper position even when patients
have restrictive anatomical structures. "We believe this feature will have
advantages as the locations and the indications treated through
neurostimulation evolve," he says.
"This is the equivalent of Œwhat you see is what you get' in visual
user-interface design, or perhaps Œwhat you feel is what you get,'" says
juror Weinger. "These leads allow for more rapid and more effective
positioning."
According to ANS, the lead's small size and steerability facilitate
placement into restricted spaces, which results in a less-invasive
procedure. "The unibody design is the result of a process whereas the lead
strands became incorporated into the inner wall of the lead," says Maruca.
"Essentially, the lead feels like Œone-piece' to the physician. The clinical
result is better rotational control of the lead. The more responsive the
lead, the better equipped the physician to maneuver the lead into confined
anatomical spaces," Maruca explains.
Cassi Rotational Core Biopsy Device
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| The Cassi rotational core biopsy device, manufactured by Sanarus Medical, is an automated large-core biopsy device for use in a physician’s office. |
The Cassi rotational core biopsy device, manufactured by Sanarus Medical (Pleasanton, CA), is an automated large-core biopsy device used in the
diagnosis of breast disease. Cassi's patented Stick-Freeze technology is
used to immobilize the target tissue, making it unnecessary to purchase
costly capital equipment.
The beauty of this device is that it enables a breast biopsy to be done in
the doctor's office. "It is a disposable, self-contained device that
provides a large-core biopsy. It is an office-based procedure that requires
no capital equipment," says juror Michael Wiklund, a human-factors
engineering consultant based in Concord, MA.
"Breast surgeons tend to work in small practices where cash flow is a big
concern. They get very worried about spending money to buy new technology
when they aren't sure how often they will use the equipment," says Russ
DeLonzor, vice president of research and development for Sanarus. "We knew
that we'd have a huge hit on our hands if we could deliver the same reliable
cores with no worries about amortizing the cost of the equipment over a lot
of procedures."
"We really like the engineering design, including the use of the CO2 to
freeze (or hold in place) the tissue to be
biopsied," says juror Weinger. The CO2 unit also drives the
biopsy mechanism pneumatically, pushing the core piston forward and then
retracting it later to extract the obtained specimen. "It doesn't require a
huge up-front capital expense, so it is easy for a small clinic or
individual clinician to purchase and use," he says.
DeLonzor says the company's goal was to deliver a product at the same cost
per use that other companies were charging for their disposable components,
but with no capital equipment. "Delivering the sophistication of an
automated biopsy device at the lowest possible cost was a tough goal," he
says. "To hit it, we knew we would have to borrow from the high-volume
consumer world for some of
our basic building blocks. From the gearmotors used in ATMs to the safety
mechanisms used in paint-ball guns, to general-purpose programmable
integrated circuits used in about everything, we designed using
off-the-shelf solutions wherever possible."
By taking advantage of these economies of scale, DeLonzor says, the company
was able to produce a highly sophisticated, completely disposable device.
"This device will make the clinical advantage of large-core biopsy devices
accessible to many more physicians," he says.
The reason automated large-core biopsy devices are worth the investment is
because they provide much more reliable tissue specimens than the
spring-loaded devices that are designed to essentially harpoon the target
lesion. "One of the downsides to previous large-core devices is the cost of
the capital equipment," DeLonzor explains. Another problem is that the
devices are fairly complicated and require the time of a trained technician
to set the equipment up before a procedure, then take it apart and clean it
after the procedure. "At the beginning of the project, physicians told us
what they really wanted was a device that worked as well as the current
automated biopsy devices, but in a single-patient-use form that doesn't
require setup or maintenance," he says.
"We've heard from several clinicians that we have met that goal and have
truly changed their practice of medicine," he says. He explains that, in the
past, if a woman came in for an appointment because she felt a lump in her
breast, the doctor would verify the lump under ultrasound, then schedule
another appointment for a day when they could set aside the time that it
takes to set up the automated biopsy device. "Because Cassi doesn't require
any setup, these clinicians are now doing the biopsy procedure during the
woman's first appointment."
There is another, subtler factor that he says drove the company to provide a
self-contained, disposable design. "The current equipment uses a large piece
of capital equipment sitting on a cart hooked up to a disposable handpiece
via a set of tubes and cords. The sheer size and weight of the equipment is
very intimidating, and many doctors prefer not to have the patient see the
device prior to use.
Our goal was to minimize the patient's anxiety by providing an
unintimidating, quiet-functioning device that requires no tubes or cords.
"Something we didn't think to write in our product specs up front, but
something we've heard from many of our physicians, is that Cassi's
presentation to the patient is far superior to the competitive
devices."
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| The ClozeX wound-closure device, manufactured by Clozex Medical LLC, closes a wound more cleanly and neatly than sutures, staples, or glues. |
The ClozeX wound-closure device, manufactured by Clozex Medical LLC (Wellesley, MA), is a coaptive wound-closure device that replaces sutures,
staples, and glues. The closure, which comes in many sizes, uses
adhesive films and mechanical action to draw a wound together in 710 days. The color-coded
device uses red, white, and blue to indicate the order in which to apply the device. "Suturing takes 1014 minutes. Using our product to close a
wound takes 2 minutes," says Ray Barbuto, vice president of manufacturing
for ClozeX. Glues take 34 minutes and require the hands of another
technician to align the tissues," he says.
Barbuto explains that it is difficult to get a straight line with sutures.
The physician must estimate what the wound will look like when it is done
swelling. If it begins to pucker, he says, the physician must cut it open
and start over,
resuturing or stapling it, which causes additional injury to the skin. The
idea behind the ClozeX device was to eliminate those issues. The device
brings the margins of the wound together and "lets the body do its job. Its
simplicity is why it works well," he says. It improves wound-closure speed,
and if a clinician makes a mistake, the ClozeX can be removed with no injury
to skin. "We see this device as a paradigm shift in the making," he says,
noting its appeal to physicians and patients.
"The ClozeX wound-closure device is the first device that approximates the edges very cleanly and neatly," says
juror Lazar. "It is very efficient for the physician."
The device was invented by ClozeX Medical's president, Michael Lebner. Just
two years ago, Lebner and Barbuto met with potential suppliers at MD&M East
in New York. "We had a wound-closure device concept. We just had to find the
right raw materials."
Key to the device's success in the marketplace is the significant time
savings, which offers great benefits to both the physician and patient. "For
doctors and institutions, time savings can improve patient satisfaction,
increase efficiencies and revenues, and reduce overall costs," says Barbuto.
"The local injection of anesthetics and the patient trauma associated with
needles can be avoided in many emergency department cases, enabling doctors
to more quickly treat patients," adds Barbuto. The ClozeX's topical design
"forgives errors" because the device can be easily removed without skin
damage. "The device is not secured until the alignment is satisfactory," he
says.
"A good design or new method of treatment should provide one of five
benefits," says juror Goldberg. "It should provide a less-invasive tool,
offer a safer alternative (or have less risk associated with it), reduce
pain and discomfort, make an existing procedure easier, or offer a time
savings," he says. "It's important to know that less time for a procedure
usually means that it is safer for the patient and that it can be done at a lower cost."
Copyright ©2005 Medical Device & Diagnostic Industry
