Roland (1 of 2) (IMAGE) UT Southwestern Medical Center Caption The DUET Electric-Acoustic System, or EAS, is worn behind the ear and implanted by special surgical techniques to preserve natural hearing. Credit UT Southwestern Medical Center Usage Restrictions Please use credit line. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.