Dr. Katherine Crothall – 2023 Kumar Patel Prize Recipient

2023 Kumar Patel Prize Recipient for pioneering contributions to CO2 laser surgical technology

Katherine Crothall, PhD

I am extremely honored and humbled to be the recipient of the 2023 Kumar Patel Prize for contributions to advancing surgical CO2 laser technology.

My interest in lasers started as a young engineer at Hughes Aircraft in 1971 when I was assigned to the group developing lasers for a variety of military applications. Hughes, at that time, had an interesting program in which I could work and simultaneously go through graduate school- all the way through to a PhD- on Hughes’ nickel! I chose the University of Southern California because it had some of the best minds in quantum electronics on the faculty. Hughes also had an incredible group of laser engineers and physicists- some of who migrated to Lawrence Livermore to head up the laser fusion program.

About the time I was starting my research for my PhD dissertation in 1973, the first CO2 waveguide laser was invented. I immediately became fascinated with waveguide lasers due to their possibility of maintaining a highly focused output beam without having to sacrifice output power or having to constantly readjust the optics. CO2 lasers, whether waveguide or conventional, at that time were excited with high-voltage direct current and required gas tanks and pumps- adding bulk, cost, and complexity. As I delved into some of the technical issues associated with CO2 lasers, I became interested in RF excitation as I saw the ability to create low-voltage, compact, rugged, sealed off CO2 lasers with RF excitation. With a skunk-works project within Hughes, I proved the ability to maintain a stable transverse gaseous discharge by applying an RF voltage across a 2 mm square channel, comprised of two glass plates separated by two 2 mm aluminum plates. With this, I received funding to build the first RF-excited waveguide CO2 laser- and shortly afterward proved the concept.

Although I enjoyed my work at Hughes and the talented people with whom I worked, I was also interested in using this RF waveguide laser technology for non-military applications- which Hughes had little interest in. So, I took the plunge in 1978 and in the garage of my home, started my first company, called Laakmann Electro-Optics. My then-husband, Peter Laakmann, who was an excellent and very creative engineer, helped me out on nights and weekends and joined the Company full-time about a year later. (Unfortunately, he passed away from lung cancer in 1997.) Shortly after we built our first prototype, we placed an ad in Laser Focus, a trade magazine. Literally, a day after the magazine was published, we received a call on our “office phone” at 7:30 AM PDT from Western Electric, asking for the order department. Thinking quickly, I said “Just a moment, please”; I put the phone on hold and answered in a disguised voice, a few seconds later, with “Order Department, how can I help you?”. Quickly scribbling down the details of the order, we were off to the races. This was one of many orders received in the first several months!

Now, the hard part started. Although our prototypes could run continuously for hundreds of hours at a time, we unfortunately, found that the shelf life of our lasers was not up to what we advertised- particularly the lasers we shipped to Japan. We discovered that shelf life was adversely impacted by water vapor and ultimately, we solved the water vapor issue by making some modifications in the processing and design of our laser. This was just the first of the issues we stumbled upon. Neither my husband, nor I had any experience in manufacturing or many other of the aspects of running a business. We stumbled along and bit by bit solved the various issues facing us. In 1980, the first medical laser using our RF waveguide laser was built. Unlike other medical CO2 lasers at that time, our laser did not require gas tanks and vacuum pumps and hence was substantially more compact and rugged. Johnson & Johnson came across our laser at a medical meeting, contacted us, and bought the Company in June 1981.

I agreed to stay on and run Laakmann Electro-Optics for 5 years post-acquisition. During this time, we designed and built a 50W surgical laser called the XA-50 which was used for gynecological and neurosurgical applications and a relatively compact laser 20 W laser called the Ambulase which was sold to medical offices to dermatologists, podiatrists, otolaryngologists, and oral surgeons. (One of the first dentists we met who showed interest in laser oral surgery was Dr. Robert Pick!) Both the Ambulase and the XA-50 had an articulating arm, which was bulky and difficult to focus. (I’ve come across a few dermatologists in the last several years who are still using the Ambulase- albeit a diminished power!) Neither of these lasers could be shipped by FedEx or UPS and had to be crated and shipped by truck and later uncrated and set up by a trained technician. Hoping to improve upon this technology, with the help of physicist Mike Levy, we developed the first hollow waveguide fiber as an alternative to the articulating arm delivery system. In 1986, we introduced the XAP, the first CO2 surgical system with a hollow fiber.

I was ready to move away from J&J in 1986 and try my hand again as an entrepreneur. After extricating myself from non-competes, non-hires, and the like, I convinced Mike Levy, Paul Diaz, and Steve Wojcik, three highly talented and creative physicists/ engineers from Laakmann Electro-Optics, to move up to Seattle and join me in starting Luxar in 1988. Our goal was to develop a 20 W surgical laser which had a truly flexible hollow fiber, with a small footprint, and was shippable by air by FedEx or UPS- and one that did not require the uncrating and set-up by a skilled technician. These goals required the development of an improved hollow fiber than what I invented at Laakmann Electro-Optics, one that was more flexible and more manufacturable. Thanks to the inventiveness of Mike Levy, we succeeded in this development and introduced the LX-20 to the market in 1989. We sold this laser for multiple applications in dentistry, oral surgery, dermatology, otolaryngology, podiatry, and veterinary medicine.

I am thrilled to see the progress that LightScalpel has made to CO2 surgical lasers since the LX-20. I should note that in addition to the invaluable contributions made by Peter Laakmann, Mike Levy, Paul Diaz, and Steve Wojcik, there were countless contributions made by other individuals who remain unnamed. A successful medical technology company requires a truly multifaceted team with expertise not only in technology and engineering, but regulatory, sales/ marketing, finance, legal, customer service, manufacturing- and most importantly the physicians, dentists, and veterinarians who use our products. Without the contributions of the named and unnamed individuals, there would have been none of the technology or products mentioned. As for myself, I went on to found and run two other medical technology companies (recruiting some of the talent from my Luxar days): Animas Corporation, a manufacturer of insulin pumps and Aspire Bariatrics, a manufacturer of an alternative product to Bariatric Surgery.