Polyurethane Sponge (image) Johns Hopkins Medicine Share Print E-Mail Caption A 2-centimeter polyurethane sponge attached to a string emerges from the capsule and is pulled through the patient's esophagus to collect genetic material that determines risk for cancer of that organ. Credit Stephen Meltzer, M.D. Usage Restrictions None Share Print E-Mail 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.