Medical equipment design
engineers are constantly challenged to develop leading-edge electronic devices that
help improve patient care. Over the last decade or so, we have seen remarkable
advances in the medical equipment marketplace, ranging from easy-to-use home
monitoring devices for blood pressure and blood sugar levels to complex
diagnostic imaging machines, sophisticated robotics and laser surgery equipment
used in hospital operating rooms.
One significant trend is the
medical industry's growing adoption of the same electronic design strategies
and components that have propelled the rapid growth of the consumer electronics
and telecommunications industries in recent years. New design strategies have
been built around increased demand for miniaturization, mobility and
portability - as evidenced by the proliferation of next-generation smart phones
and other handheld devices, as well as notebook and tablet computers.
It is easy to understand why
these same market forces - the demand for increased miniaturization, mobility,
portability and ease of use - are similarly driving convergence of electronics
and medical devices. With rising healthcare costs has come increased reliance
on patient-administered home monitoring and therapeutic devices. On the healthcare
provider side, there is greater demand for more innovative and affordable
electronic equipment for use in diagnostic labs, hospitals and clinics.
Key Technology Trends
As much as the following trends
are impacting the creations of medical device design engineers, they are also
affecting the key elements required by engineers to design unique and
solutions-based medical products.
Mobility. Telemedicine is the delivery of healthcare services
and information via wireless telecommunication technology. Two types of
telemedicine are directing associated device development: The transmission of diagnostic
images and test results between and among medical professionals via broadband
networks; and establishing direct connections between physicians and patients
Fiber-Optic and Laser Technology. In digital imaging and diagnostic applications,
optical fiber cables are increasingly replacing copper-based cables. Fiber-optic
connectivity provides higher speeds for faster downloads and ensures more
reliable, distortion-free electrical signal transmission, thereby improving the
image quality. Optical cables can eliminate ground loops and EMI/RFI, which
provides better clarity on video displays of MRI and X-Ray imaging.
Optical fiber is also being
used in sophisticated laser surgical devices, which are becoming more common as
a preferred tool for performing a multitude of minimally invasive therapeutic
procedures. In laser surgery, the laser's light is transmitted using flexible
optical fiber smaller than half a millimeter in diameter.
Miniaturization and Portability. The demand for smaller and more portable form factors
for medical devices is driving the miniaturization of embedded electronic
components and interconnects to unprecedented micro sizes. Microminiature
connectors, for example, designed for use in mobile phones and handheld
devices, have now evolved into viable medical device solutions.
In selecting micro
connectors, product designers need to carefully assess and compare marketplace
offerings to ensure that all performance and reliability requirements will be
met. One popular connector available in the marketplace today has an extremely
small (0.40 mm) pitch, a low-profile height of 0.70 mm, and comes in several
configurations to accommodate a variety of device designs.
User Interface Keypads and Switches. Ease of use and aesthetics are key factors in
designing user interface pads and touch-point switches for home monitoring
medical devices. Adapted from the white goods industry, membrane switches not
only provide an excellent value-to-performance ratio, they are also rugged,
easy to clean and intuitive to use. Design elements may include such additions
as embedded LEDs, dome arrays, silicone rubber keypad assemblies and
Critical Design Factors
Major factors medical device
designers must consider to ensure each product's safety, performance and
reliability include: the product's operating environment (e.g., hospital, diagnostic lab or home), interconnect sealing
requirements, bio-compatibility, intuitive operation, resistance to
sterilization and cycle life durability.
Once these factors have been
considered, designers may find it necessary to tweak or modify COTS (commercial
off-the-shelf) components to meet specific application requirements. In many
cases, taking a MOTS (modified off-the-shelf) approach can be a practical
alternative that allows for some level of customization without the cost
burdens of custom tooling.
Anthony J. Kalaijakis is
strategic medical marketing manager for Molex Inc.
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