COLUMBIA — Imagine going to the doctor for cancer treatment and being able to leave, cancer-free, that same day.

According to MU research, ultrafast lasers could make that a reality.

Robert Tzou, chairman of the MU department of mechanical and aerospace engineering, and his colleagues started looking at the ultrafast femtosecond laser as a way to provide minimally invasive and less painful medical procedures.

A femtosecond is a quadrillionth, or one billionth of a millionth, of a second.

With the click of a pen-like laser, dentists could remove cavities; surgeons could make clean cuts for knee replacements; and cancerous cells could be eliminated without harming the healthy surrounding cells. The laser would also be able to track how a drug has delivered into a human body, provide pain relief and replace psychologically or physically damaging medical treatments, such as chemotherapy.

All these medical breakthroughs, however, could not happen without a research team or donors, who helped the department fund its research and buy a femtosecond laser.

The MU group is not the only one to work with lasers. Several groups around the U.S. are also looking at femtosecond laser applications. A team at the University of Michigan has reported that it has produced the most intense laser beam yet with a femtosecond laser. The Mazur group at Harvard University has published research on femtosecond laser dissection within cells.
Tzou said he and his colleagues were the first group in the world to come up with engineering models that described the ways ultrafast lasers interact with certain materials. At first, they analyzed responses between femtosecond lasers and metals. After digging deeper, they also started using silicons.

In 2003, James Thompson, the dean of MU’s College of Engineering, gathered 18 people from the different departments in the college, along with Tzou and some members from the department of computer science, to create a team of faculty that would look more in depth at femtosecond laser application. In 2005, the team added J.K. Chen, who was doing laser research at Kirtland Air Force Base in New Mexico.

“We have to constantly ask ourselves, ‘what is it that we can do that other people can’t?’” Tzou said.

Because MU does extensive research in life sciences, the team members asked themselves if they could use ultrafast lasers to process biological or medical samples. The idea was to capitalize not only on the strengths within the engineering school, but strengths of MU as a whole.

“In order to tackle applications of ultrafast lasers and life sciences, we needed medical people,” Tzou said. “We further introduced six surgeons into the team, so now we have 25.”

By late 2005 and early 2006, the team completely turned its efforts into researching how the femtosecond laser could benefit the life sciences.

The laser can produce pulses that last one-quadrillionth of a second, providing an intensity that could potentially remove any known material. Because the pulses are so fast, energy from the pulses does not have time to transfer to the area outside the laser’s target, and the surrounding area remains unscathed.

The problem, at that point, was obtaining a femtosecond laser. The team had been using models, but in order to advance its efforts, it needed to be able to test ideas on a real laser. To help raise money for the laser, the Dean’s Engineering Advisory Council and Engineering Development Office looked to the college’s alumni.
Al Eberhard, executive director of advancement in the development office, found engineering alumnus William Thompson, who was interested in the femtosecond laser research. Thompson and his wife, Nancy, met with James Thompson and Tzou in St. Louis.

“We presented our vision, existing success, our team and our plans for ultrafast lasers,” Tzou said. “Toward the end of the meeting, he said, ‘OK, I’ll let you know shortly.’”

Although James Thompson and Tzou felt good about their presentation, they were not sure if the Thompsons would be willing to give them $500,000 for the laser research because they had just donated $8.5 million to found an autism center at MU.

Within two weeks, however, the Thompsons contacted Eberhard to say they would donate the money.
The femtosecond laser was $220,000. They also bought an optical table, which helps stabilize the laser, microscope and other peripherals, bringing the total to around $500,000.

Femtosecond lasers usually cost $100,000. However, most of them have fixed parameters, so the wavelengths always stay the same.

“The laser we bought has a unique feature,” Tzou said. “It has adjustable wavelengths from the infrared to the ultraviolet range.”

The team already had another femtosecond laser in its lab, but it has a fixed wavelength, which makes it not as effective for research. This one has a wavelength of 750 nanometers, which cannot be adjusted. Lasers with fixed parameters, according to Tzou, are perfect for use in dentistry.

A group of dentists from the University of Missouri–Kansas City visited Tzou and his colleagues to explore the use of a femtosecond laser for cavities. For gum disease and teeth cleaning, the dentist would simply shine the laser on the tooth and be finished. Before the laser can be used, however, the team needs research funding to elaborate on the uses of the technology. Tzou said the group would try to get funding from the National Institutes of Health.

“Technically, it’s ready,” said Tzou of the laser. “But for medical applications, we’re looking for support from NIH to tie all the nuts and bolts.”

The NIH are part of the U.S. Department of Health and Human Services. In order to receive a grant from the NIH, Tzou and his team need to provide preliminary data, which will be collected this summer from 20 specimens of teeth shipped from UMKC. A grant from NIH lasts three years, and the team plans to have the proposal for research out by early September 2008.
Funding would help the team find ways to make application of the laser user-friendly.

“After we generate the laser pulse, we need to move the pulse into optical fibers, like in a pen,” said Tzou.
A pen format would allow a doctor to use the laser with little to no training and would make it more portable. The team hopes that the pen will be able to find a place in operating rooms and doctors’ offices around the world to help minimize the length of time a patient spends in recovery. Ideally, the doctor would be able to pinpoint cancerous cells, shine the laser on them and cut them out of the body without damaging surrounding cells.

The laser is also an ideal candidate for knee replacement surgery, said Tzou. However, the laser would have to be used for a longer period in the operating room, so overheating would be an issue. If the laser gets too hot, it may not be able to repeat the same results effectively. For the team, repeatability, stability and efficiency must be ensured before the laser can be used for medical purposes.

In addition, the team is still looking for ways to refine potential problems with the laser’s use. For example, if a doctor removes some cancerous cells, there needs to be sort of “retrieval system” to collect the cancer.

“You can’t leave debris in humans,” Tzou said.

Tzou’s vision for engineers is to focus on creating technologies, like the femtosecond laser, that can benefit people. Research on the laser can help bring people closer to treatments without damage or side effects.

“Before I retire, if I can push a tenth of it, I will be happy,” he said.