Our Providers

Ellen Dy, MD

Dr. Ellen Dy, medical director of the Gastroenterology Center at Valley View, is a board-certified gastroenterologist with 24 years’ experience in practice. Dr. Dy earned her medical degree from Indiana University School of Medicine, with residency at Indiana University Medical Center. She completed her gastroenterology fellowship at University of Texas Medical Branch in Galveston, serving as Chief GI Fellow in 1994-1995.

She then completed an advanced therapeutic endoscopy fellowship at Allegheny General Hospital in Pittsburgh, with advanced training in procedures such as ERCP (Endoscopic Retrograde Cholangio-Pancreatography), palliative biliary drainage and enteral stenting. After fellowship, she practiced in Des Moines, Iowa at Mercy Medical Center for 21 years, serving as the GI Chair for two years before relocating to Colorado. Before joining Valley View in spring 2020, she worked at Alpine Gastroenterology at Glenwood Medical Associates.

Dr. Dy is a member of the American Gastroenterological Association, American College of Gastroenterology, and the American Society of Gastrointestinal Endoscopy.

Gerard Tomasso, MD

Dr. Tomasso is a board certified gastroenterologist who has practiced in the Glenwood Springs community for over 38 years. He joins the Valley View team part time, as he moves toward retirement. “When I was 15, I worked in a hospital and realized I wanted to be a doctor. I enjoyed working with people and I was good in science. I had a great teacher during my residency who interested me in gastroenterology. Today, I enjoy being on a first-name basis with my patients, and I get good feedback from them.”

Valley View Hospital | 1830 Blake Ave, Suite 202 | Glenwood Springs, CO 81601 | 970.384.7510