He is especially interested in bronchoscopy. Dr. Keller's hospital/clinic affiliations include Northwestern Medicine Central DuPage Hospital, Alexian Brothers Medical Center, and Suburban Lung Associates. He is an in-network provider for United Healthcare Plans, United Healthcare Choice, United Healthcare EPO, and more. His practice is open to new patients. Before completing his residency at McGaw Medical Center of Northwestern University, Dr. Keller attended medical school at the University of Iowa, Carver College of Medicine.