Have you heard this One before?

Short Tales from a Life in Medical Device Technology

Experiences I had or that others shared that you may find enlightening, amusing, or maybe just scary...
New ones will be added over time. Stay tuned.

Do Something New and You'll Find Something New (or Obscure)

I was doing some contract work for a start-up developing an ultrasound device to speed up clot busting in strokes. An ultrasound transducer operating at 30 kHz would be affixed to patient's head while a clot-busting drug was administered. "Everyone knows" that sound at that frequency is not audible, so no worries there...

One afternoon after everyone else had left, I was wondering whether I would notice anything when I put one of those transducers on my head and turned it on. When I did, I suddenly heard this painfully loud beep in my ears, so I immediately turned it off again. Quick check - yes, it operated at the intended frequency and output level. So maybe where I put it on my head was too close to my ear?

Putting it on my forehead didn't change anything. Out of a whim I tried my chest - still could hear it, but less loudly. Held it to the palm of my hand and still there was a faint sound to be heard. Now that posed an unexpected problem. No patient would tolerate this treatment even for a minute.

Eventually we figured out what was going on. We even found one research paper that reported something similar in Navy divers exposed to ultrasound signals. (This was right around the beginning of the new millenium and not everything could be found on the internet...)
The human inability to hear frequencies above around 20 kHz is caused by the middle ear. It operates as a low pass filter (and as we get older, that cut-off frequency drops). Since the ultrasound transducer was sending sound directly into the body, it was conducted to the inner ear via the skull, going around the middle ear. But the inner ear is capable of processing very high frequencies. The cut-off appears to be somewhere around 250 kHz!

In a heroic effort the start-up within a few months completely redesigned their device to operate at 300kHz. During the following clinical trial, another discovery was made. But that's a story for another day.

Is Clinical Data Enough to Drive Market Adoption?

“You need to show clinical evidence that your medical device provides a benefit” is a common request that early medical device innovators hear after they gain regulatory clearance. It’s rational, especially for a profession that is deeply rooted in science.

But after this clinical evidence is captured and published, does it initiate customer purchasing and market traction? Unfortunately, the answer is typically “no.”

Together with Eric Sugalski I have written a short article on the realities of new device adoption. Solid science is required (even though some technologies are used without it), but there are many other factors that drive adoption. You can find the article here.

Eric is Founder and CEO of Archimedic, an ISO 13485 certified contract product development firm that is 100% focused on helping clients develop life-changing medical devices.

Challenges of Research with Home-Use Devices

While gathering clinical evidence with devices in a hospital setting is common and well understood, studying use and efficacy of devices at home poses some very different challenges. Patients may not use a device as intended, or may not use it at all. And they are unlikely to provide reliable documentation.

Finding that out at the end of a study can be an unpleasant surprise. However, there are a number of measures that can be put in place but they need to be part of device design.

In another collaboration with Eric Sugalski I have written a short article on how to make collection of clinical data at home more reliable. You can find the article here.

Eric is Founder and CEO of Archimedic, an ISO 13485 certified contract product development firm that is 100% focused on helping clients develop life-changing medical devices.

Can you win against a Gold Standard?

What is a diagnostic Gold Standard (sometimes also called reference standard)? It is the “best available test under reasonable conditions” meaning it is a test that is accepted by the medical community to be the best to identify a specific disease.


Now imagine you have found a better or cheaper way to test for a disease than the current gold standard. The medical community will be ecstatic and immediately switch over to this new and improved test, right? Well…


Keep on reading here for a discussion of what you will likely be facing.