Enlightened Innovation: Invention of the Dual-Balloon Barostat


Sam Jundler (ECE MASc 9T1), founder of G & J Electronics Inc., was working on his thesis project—the creation of a gastric pacemaker, supervised by Professor Berj Bardakjian—at Dr. N. E. Diamant’s Toronto Western Hospital lab in 1990 when inspiration struck.

Researchers at the lab were working with a device invented by the Mayo Clinic called the Barostat, used in research to help inflate a balloon, thereby regulating pressure, within a cavity. The device didn’t work; so Jundler, a then master’s student, was asked if he could lend a hand. Just happy to be of assistance, he had no idea that lending his engineering know-how to this small experimental device would be a life-defining move.


Jundler’s Dual Balloon Barostat

“I moved one wire over and it worked,” Jundler says now of his invention.

The original Mayo Clinic Barostat model was designed with respirator bellows, which made the inflation of the balloon distorted and stretchy–in short, impractical for the kinds of research being conducted with the tool. After noticing the ease by which Jundler had been able to make this research tool viable, the laboratory researchers asked him to design a new, more functional device—a challenge he welcomed.

By computerizing the Barostat and developing the software necessary to control the device, and adding a rigid cylinder and piston, Jundler was able to solve the problems associated with the original Mayo Clinic model.

The Isobar 3, a Single Balloon Barostat model, was developed in 1992, which Jundler followed with the Distender Series I in 1993 and the Distender Series II in 1994. This third model, a Dual-Balloon Barostat, can inflate and regulate two balloons at two separate pressures simultaneously.

In 2000, noting that the Barostat series was being used in laboratory research, Jundler designed a fourth model, The Distender Series IIR, specifically for use with research rats.

The Barostat works by keeping pressure in a balloon, attached to the tip of a catheter, constant, so that changes in organs are reflected in an indirect way. The Barostat has become known as an effective research tool for pain studies, and has been used in research on Irritable Bowel Syndrome, rectal dysfunctions, cancer, and even functional MRI’s, where the Barostat, controlled by the MRI software, is used to study how rates of inflation affect the brain.

Now Jundler’s Barostat—of which Sam Jundler’s company is the sole maker—is used all over the world, and from as far away as the Royal London Hospital, the Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand, University of Adelaide, Australia and the Mayo Clinic, which adopted Jundler’s models in lieu of their own.

“Over 20,000 experiments have used our Barostats,” Jundler says proudly of his invention. Between eight and 15 Barostats are delivered each year, while total revenues from the Barostat have topped several million.

Learn more about IBBME’s Neural, Sensory Systems & Rehabilitation research theme.