While helping run the ultrasound division, Goldberg said, Mr. Darby "started the vascular laboratory at Jefferson, which was the first such accredited lab in the United States."
The lab "looks at blood vessels throughout the body by using sound waves," Goldberg said, "without the use of radiation."
And Mr. Darby, he said, "developed the first ultrasound training program for sonographers in Philadelphia, in the early '80s," referring to medical professionals who use sound to produce diagnostic images.
That program, he said, is now run by the College of Allied Health Professions at Jefferson.
Jefferson also houses the Collaborating Center for Ultrasound Education for the Developing World, recognized by the World Health Organization, Goldberg said.
"It is the only center for general ultrasound education for developing countries," Goldberg said, "a conduit for Joe and others to develop educational materials" for health professionals visiting Jefferson.
Mr. Darby visited developing nations, including Cyprus, and helped set up ultrasound education centers there, Goldberg said.
He "was a mentor to everyone he worked with," Goldberg said, "helping to bring out the best of their capabilities."
Born in Philadelphia, Mr. Darby graduated in 1965 from Cardinal Dougherty High School and was an Army military policeman in West Germany.
He earned a bachelor's degree in biomedical engineering technology at Temple University in 1974.
"Jefferson was his heart and soul, apart from his family," Mr. Darby's wife, Frances, said.
He was a member, among other organizations, of the American Registry of Diagnostic Medical Sonographers.
In addition to his wife of 39 years, Mr. Darby is survived by a son, Patrick; a daughter, Lauren Darby; two brothers; and a sister.
Visitation was set for 8:50 to 9:50 a.m. Friday, Sept. 14, at St. Helena Roman Catholic Church, 1489 DeKalb Pike, Blue Bell, before a 10 a.m. Funeral Mass there, with burial in St. Matthew Cemetery, Conshohocken.
Donations may be made to the Joseph J. Darby Memorial Scholarship Fund at the Jefferson Foundation, Suite 110, 925 Chestnut St., Philadelphia 19107.
Contact Walter F. Naedele at 215-854-5607 or wnaedele@phillynews.com.