Imagine pushing a button at the first substernal burning twinge to activate your implanted esophageal acid-sensing RFID tag and wirelessly transmitting the data to your cellphone for review at your next doctor’s appointment. Sound crazy? Well, doctors at UT Southwestern Medical Center are working on just such a device.
The new system involves pinning a small, flexible RFID chip to the esophagus, where it remains until removed by a physician. The chip, about two square centimeters, or a little bigger than a dime, tests for electrical impulses that signal acidic or nonacidic liquids moving through the esophagus. It then transmits data to a wireless sensor worn around the neck.
The device, presented May 23 at the Digestive Disease Week conference in Washington D.C., is still in the test phase. But researchers believe it will be a welcome replacement for current standard procedures, which require placing a flexible catheter tube through the nose and down into the esophagus.
“The procedure is very uncomfortable and because of the catheter, you can’t eat or drink the way you normally would. The test results can be biased because you change the way you eat,” explained Dr. Tang.
No catheter is required with the RFID system, so doctors are hopeful that the system makes it easier to follow normal eating, drinking and activity patterns that may play a part in the acid reflux. Researchers say patients shouldn’t feel anything in their throat when the device is inserted thanks to a special plastic material used.
Researchers have already successfully tested the new RFID device to see that it properly identifies simulated stomach acids in a test tube and that the transmitter can send the results through human tissue. The sensor is designed to detect stomach acid, gas and water so doctors can determine whether the presence of those substances coincides with feelings of heartburn, the start of eating or other activities. The next step will involve testing in animal models before the system eventually is tested in humans.
UT Southwestern’s Dr. Tang and Dr. Fred Tibbals, director of the Bioinstrumentation Resources Center, have been working with Dr. Jung-chih Chiao, associate professor of electrical engineering at UTA, for two years to develop the wireless system. Engineers had to develop the specialized radio frequency implant, which detects and sends the data, as well as the receiver. The receiver will include a button the patient can push when they begin eating. Eventually, engineers hope to design a devise similar to a personal digital assistant to store the results. That PDA-like device could then be taken into a doctor’s office and downloaded into a computer to analyze the results.