seal  Purdue News



January 20, 2004


Purdue honors faculty inventor 

Bioengineer, 82, leads by example to improve lives, create jobs 

WEST LAFAYETTE, Ind. – Burn victims today heal with fewer scars, heart patients exercise with greater confidence, athletes and aging baby boomers can have their ligaments and tendons restored almost like new, thanks, in large part, to an 82-year-old bioengineer who isn't about to retire.

Leslie Geddes
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Leslie Geddes, Purdue University's Showalter Distinguished Professor Emeritus of Bioengineering, was honored for turning discoveries into medical miracles as well as jobs for Indiana. Geddes received the university's Outstanding Commercialization Award today (Tuesday, 1/20) to recognize his 30 patents, many now licensed by Indiana companies. Patents and technologies spawned in Geddes' lab have generated $15 million in royalties for Purdue.

"Thanks in part to Professor Geddes, Indiana is now a national leader in biomedical industries," said Purdue President Martin C. Jischke. "Quite simply, Les Geddes is one of the most prolific inventors in the history of Purdue University.

"He has developed and commercialized a truly exceptional array of technologies that have had an enormous impact on the health and welfare of people worldwide."

Don K. Gentry, vice provost for engagement, said the award is presented to Purdue faculty who are especially successful at translating ideas into commercial products.

"Among the many Purdue faculty who have used their research to make a direct impact on our everyday lives, Les Geddes is a legendary pioneer," Gentry said. "The world is a better place because of his vision and wisdom."

During the 3:30 p.m. award ceremony, Geddes delivered a lecture entitled "The Perfect Prosthesis?" The title refers to the fact that researchers have not come close to exhausting all of the possible uses for one of his research team's discoveries, a regenerative tissue graft made from a layer of a pig's intestines known as small intestinal submucosa, or SIS.

The title refers to the fact that researchers have not come close to exhausting all of the possible uses for one of his research team's discoveries, a regenerative tissue graft made from a layer of a pig's intestines known as small intestinal submucosa, or SIS.

"The question mark in the title is there because we don't know how many places it will be used in the body," Geddes said. "We don't know its limits yet."

Linda P. B. Katehi, the John A. Edwardson Dean of Engineering, said Geddes has been driven throughout his career to stick with an idea until it becomes a product.

"At the same time, he is greatly admired for his dedication to teaching," Katehi said. "He's a remarkable person."

Geddes officially retired in 1991, but he still comes to work every day around 5 a.m., teaches a course at 7:30 and has three ongoing research projects, one of which is funded by the National Institutes of Health.

"Doing research is like peeling an onion," said Geddes, who has written more than 700 scholarly articles and taught 2,000 biomedical engineers. "You are crying as you are tearing away the layers of ignorance. And you finally get down to the truth, the center of the onion, after all those layers of ignorance you've peeled away."

Geddes said he's never relished the idea of turning his inventions over to someone else for commercialization.

"I don't want to stop just after the principle has been discovered," he said. "Researchers tend to stop and hand it over to somebody else who then has to reinvent the wheel. They have to come up to speed and learn all about the things that I had done, and all the mistakes that I made they would have to make, so I like to avoid that."

He and his research team from Baylor University College of Medicine were recruited to Purdue in 1974 to help the university develop an organized biomedical engineering program and create new technologies in the field.

Geddes hasn't stopped producing since then.

"I think one of his key attributes is his ability to inspire people, including students, faculty and industrial collaborators," said George Wodicka, head of the Purdue Department of Biomedical Engineering and a professor of both electrical and computer engineering and biomedical engineering. "Everyone who works with him is energized by his curiosity and his willingness to test out new ideas in the laboratory.

"He provides a real spark, even at his current age, for the students, and he's an excellent role model for the younger faculty that we are bringing in to grow the biomedical engineering department."

Geddes' work has brought monetary benefits to Purdue as well. One-third of the $15 million in royalties goes into the university's venture fund, which supports other research to develop new technologies. Indiana-based companies that have licensed and commercialized Geddes' inventions are Cook Biotech Inc., DePuy Inc., Eli Lilly & Co., Hillenbrand Industries, Cook Inc., Technology Transfer Inc. and Theron Inc.

Among his team's many accomplishments are: an automated miniature defibrillator – a device that jolts the heart with electricity during a heart attack – that is small enough to implant inside a person; a pacemaker that automatically increases a person's heart rate during exercise; a portable electrocardiograph that patients use to monitor the electrical patterns of their own hearts; and a miniature cuff that fits over the pinky-size limbs of premature infants to measure blood pressure, heart and respiratory rate, and the amount of oxygen in the blood.

No single device currently exists to non-invasively and accurately collect the potentially life-saving data from the more than 300,000 premature babies born annually in the United States. The cuff isn't quite ready for market, but it is being perfected by engineers at Theron Technologies LLC, a joint venture of Barnard Life Sciences LLC and Theron Inc., based in Carmel, Ind. Clinical trials are expected in late summer.

Hot out of his lab is a new device that tells medical personnel whether they are properly administering cardiopulmonary resuscitation, in which force is applied to the patient's chest to get the heart pumping. The device is placed on the patient's forehead and produces a high-pitched whistling sound that indicates whether the proper amount of force is being applied to the chest.

Geddes said, however, that his biggest achievement by far was leading the team that discovered SIS. The researchers were surprised to discover during the early 1980s that grafts of this material acted as scaffolds that enabled the body to regenerate tissue damaged by injury or disease. The scaffold-like grafts disappeared and were replaced by the body's own tissue.

Surgeons have used the material to treat more than 175,000 patients so far.

Geddes said SIS was discovered by accident. The researchers originally were looking for a way to avoid lung transplants by using tissue from the small intestine to deliver oxygen to the blood. When the small intestine proved impractical for that purpose, researchers studied whether tubes made from the small intestine could be used to replace damaged arteries. But enzymes in the intestine digested the sutures when the tubes were sewn in place.

"Then one of our team members scraped off the lining, which has the digestive enzymes in it, and he stripped off the smooth muscle layer so it was a tube of collagen," Geddes said.

Research revealed that this stripped-down version of the small intestine enabled animals to regenerate a new artery in place of the graft.

"That was a stunner," Geddes said.

A series of subsequent experiments showed the same results for various parts of the body, including tendons, the urinary bladder, the heart muscle and a covering of the brain called the dura, which is damaged in head injuries.

The discovery changed how the medical community viewed prosthetic replacements.

"Prior to SIS, prosthetic materials were only manmade things," Geddes said. "You put them in and they stay the same for the life of the subject. SIS undergoes a series of changes and becomes host tissue. So this required a complete rethinking of the meaning of the word prosthesis."

Two Indiana companies, Cook Biotech, created at the Purdue Research Park as a result of SIS's discovery, and DePuy Orthopaedics in Warsaw, Ind., have used the material for a wide variety of surgical applications over the past decade. Cook, with 70 employees, is expanding and adding a 55,000-square-foot facility to accommodate growth. DePuy is a subsidiary of Johnson & Johnson and is the oldest manufacturer of orthopedic implants in the United States. The company designs and manufactures orthopedic devices and supplies including hip, knee, ankle, shoulder, wrist, elbow and finger replacements. DePuy has created a new group, DePuy Biologics, which has more than 20 employees and uses SIS in its Restore Orthobiologic Soft Tissue Implant.

"This product has rapidly become the gold standard in orthopedic surgery for the repair or reconstruction of rotator cuff injuries," said Dick Tarr, vice president of research in emerging technologies at DePuy.

DePuy's Restore implant has been used to treat more than 15,000 patients since it received U.S. Food and Drug Administration approval for limited uses in 1998. DePuy recently received FDA clearance to expand the use of the implant for all of the tendons of the shoulder's rotator cuff. Nearly 300,000 rotator cuff surgeries are performed in the nation every year, and sales of the implant are expected to increase as a result of the expanded approval.

Cook uses SIS for non-orthopedic applications, including the treatment of hernias, chronic wounds and burns, repairing the brain's dura covering, and creating a "sling" that repositions a woman's bladder to treat incontinence.

"A gal lost part of her nose in an accident and was so disfigured she wouldn't go outside," Geddes said. "They reconstructed her nose with SIS and you can't tell that she had an injury.

"A kid in Bloomington had a gunshot wound to his foot. They patched the wound with SIS and you can hardly tell the difference now."

A key factor in Geddes' success has been his diverse education — bachelor's and master's degrees in electrical engineering and a doctoral degree in physiology – said longtime colleague Robert Hannemann, a pediatrician and chemical engineer who was a member of the search committee that brought Geddes to Purdue.

"His electrical engineering background has enabled him to become an expert on electrical phenomena within the body, and obviously the place where that's most important is in the heart because the heart has its own electrical system," said Hannemann, who is a visiting professor of biomedical and chemical engineering and child psychology. "But he's such a multifaceted person.

"One reason he's such an excellent teacher is that he is able to translate what are sometimes fairly complex physiologic principles, like blood pressure, into very understandable terms. In fact, he still gives lectures to my students.

"He's not condescending in any way. He is very eager for the students to understand what he's saying, and if they don't, he's going to explain it to them until they do understand."

Wodicka said he doesn't think retirement will be an option for Geddes in the near future.

"This work is what he loves to do," he said. "What I try to do and what the department tries to do is to provide an environment in which he can excel."

Writer: Emil Venere, (765) 494-4709,

Sources: Martin C. Jischke, (765) 494-9708

Leslie Geddes, (765) 494-2995,

George Wodicka, (765) 494-2998,

Linda P.B. Katehi, (765) 494-5346,

Robert Hannemann, (765) 494-4079,

Madia Milks (Cook Biotech), 888-299-4224,

Monika Gibson (DePuy), (574) 372-7362,

Purdue News Service: (765) 494-2096;

Leslie Geddes, Purdue's Showalter Distinguished Professor Emeritus of Bioengineering, and doctoral candidate Rebecca Roeder, test a device they invented that uses optical techniques to measure the vital signs of premature infants. (Purdue file photo/Vincent Walter)

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