Joanna and her husband came from Tennessee and then Iowa where Joanna was the first female radiology faculty member, arriving in Arkansas on July 4, 1976 to help develop a Children’s Hospital for this state. She was the first director of radiology at Arkansas Children’s Hospital (ACH) that was a trained full time pediatric radiologist. When the department of Pediatrics moved to Children’s Hospital from UAMS under the leadership of Dr. Bob Fiser, who actually recruited Joanna to Arkansas, she helped developed a department of pediatric radiology at ACH which grew from herself to its soon to be present number of sixteen. Her areas of interest as a pediatric radiologist were neonatology, ultrasound and Sickle Cell Disease. She helped develop an ultrasound test to determine whether a child with Sickle Cell was at risk to develop a stroke, the most life-threatening complication of their disease. She also was part of an international study evaluating improving health of premature babies that could be less at risk by studying several methods of treatment to the mother before delivery. She was a primary author of one of the most popular books on pediatric radiology, Pediatric Radiology Casebase, now in its second edition. She has written and contributed to several other radiology and pediatric textbooks and written over 100 peer review articles.

Joanna was named one of three "women of distinction" in Arkansas in 1992 and has been named one of the top 100 women in Arkansas by Arkansas Business for several years as well as being on the list of outstanding doctors in the country for many years.  She is a former president and chairman of the board of the Society for Pediatric Radiology.  Arkansas Children’s Hospital annually gives an award to the physician at the hospital who embodies teamwork in his or her practice. The award is named the Robert and Joanna Seibert award. This year in 2017 she has been named to the Arkansas Women’s Hall of Fame.