[1] Cleveland Clin Fdn, Dept Gastroenterol & Hepatol, Ctr Swallowing & Esophageal Disorders, Cleveland, OH 44195 USA
[2] Cleveland Clin Fdn, Dept Quantitat Hlth Sci, Ctr Swallowing & Esophageal Disorders, Cleveland, OH 44195 USA
[3] Cleveland Clin Fdn, Div Radiol, Dept Thorac & Cardiovasc Surg, Cleveland, OH 44195 USA