Karen A. Diefenbach, MD, is the director for Minimally Invasive Surgery at Nationwide Children's Hospital and associate professor in the Division of Pediatric Surgery at The Ohio State University College of Medicine. Dr. Diefenbach comes to Nationwide Children's from Yale University School of Medicine and Yale New Haven Children's Hospital, where she was an attending surgeon and an assistant professor in the Department of Surgery.

Dr. Diefenbach completed her residency in general surgery at the University of Illinois, OSF St. Francis Medical Center. She completed her training in Pediatric Surgery at Yale University School of Medicine. Her clinical interests include minimally invasive surgical approaches to the correction of neonatal congenital anomalies such as tracheoesophageal fistulas and esophageal atresias, diaphragmatic hernias, intestinal atresias, and congenital lung lesions. She has a strong commitment to surgical education and has developed the first neonatal training devices for neonatal laparoscopy and thoracoscopy, which are used in minimally invasive surgery courses here in the United States, as well as internationally. She is also the associate director of Surgical Education at Nationwide Children's Hospital.