Natural Sciences and Engineering Research Council of Canada
Symbol of the Government of Canada

Common menu bar links

Past Winner
2008 Innovation Challenge Award

Darren Kraemer

Surgery with Mid-IR Picosecond Lasers

University of Toronto


Research conducted by Darren Kraemer at the University of Toronto is paving the way for a new generation of laser-based medical tools that can do their job with unprecedented precision. His work earned him the $10,000 first prize in NSERC's 2008 Innovation Challenge.

Dr. Kraemer's work originally set out to generate a better understanding of some of the behaviour of water molecules, discovering new interactions that have changed traditional thinking in this area. In order to conduct his research, he used a mid-infrared laser that delivers ultra-short pulses of light to excite water molecules. Since human bodies are made mostly of water, this technology turned out to have tremendous potential for use in surgery and other medical procedures.

Laser-based scalpels have been envisioned since the invention of the laser, but their usefulness to date has been plagued by the fact that a beam powerful enough to cut tissue also does damage adjacent to its path and delays healing. Dr. Kraemer and his colleagues found that a laser that is tuned to the mid-infrared and delivers light in pulses measured in picoseconds (millionths of a millionth of a second) solves this problem. The wavelength of the laser interacts with the vibrational frequency of water or other constituent molecules and is efficiently transferred to mechanical energy that removes tissue. The process occurs so quickly that there is no time for the beam to damage surrounding areas.

Until now, lasers capable of producing these pulses at the necessary power levels have been large machines found only in major research facilities. Drawing on his engineering background, Dr. Kraemer solved numerous technical problems in order to come up with a small, simple and affordable device that can be scaled for the needs of various medical procedures.

The result is laser technology that, for the first time, rivals the precision and limited invasiveness of a mechanical scalpel. Dr. Kraemer and his colleagues have taken out patents and formed a company, Attodyne Inc., to further refine and test the technology with the hope of applying it for dentistry, oncology, plastic surgery and other medical needs. He also expects his discoveries to lead to applications in areas such as precision machining, manufacturing and imaging.