University of Texas Southwestern Medical Center physicians and University of Texas-Arlington engineers created the monitoring system that combines the use of radio frequency identification, or RFID impulses, with impedance monitoring.

"We always want to come up with something that improves what we do on a daily basis," said Dr. Shou Jiang Tang, an assistant professor of internal medicine who specializes in therapeutic endoscopic innovations.

Approximately 19 million people suffer from gastroesophageal reflux disease, which is caused by stomach content moving from the stomach into the esophagus.

The new system involves pinning a small, flexible RFID chip to the esophagus, where it remains until removed by a physician. The chip, about the size of a dime, tests for electrical impulses that signal acidic or non-acidic liquids moving through the esophagus. It transmits data to a wireless sensor worn around the patient's neck.

The device -- part of a growing effort to develop less invasive technologies for gastrointestinal diseases -- was presented last week in Washington during a Digestive Disease Week conference.