Our community mourns the loss of an extraordinary colleague and friend, Dr. Harrison H. Barrett, Regents Professor Emeritus of Optical Sciences and Radiology and Imaging Sciences at the University of Arizona, who passed on November 22, in Tucson. Known to many as Harry, he was recognized worldwide as a pioneer in imaging science, combining profound expertise in the physics and mathematics of biomedical imaging with a rare devotion to teaching and mentorship.
Harry’s career at the University of Arizona spanned decades, with appointments in the Wyant College of Optical Sciences and in our Department of Radiology and Imaging Sciences. Even after his formal retirement, he remained an active and valued member of our community, contributing to NIH-funded projects and continuing to engage deeply in scientific problem-solving.
His work fundamentally reshaped how imaging systems are understood and designed. He developed a rigorous framework for assessing image quality, advanced computational methods that still guide imaging performance evaluation, and made landmark contributions to single-photon emission computed tomography (SPECT). In 1998, he co-founded the Center for Gamma-Ray Imaging at the University of Arizona, a focal point for innovation and collaboration in medical imaging.
Harry’s impact extended far beyond his own laboratory. He held numerous patents, influenced both clinical practice and basic science, and earned many honors, including election to the National Academy of Engineering and the establishment of the SPIE Harrison H. Barrett Award in Medical Imaging. Yet his greatest legacy lives on in the students, trainees, and colleagues he inspired.
This loss feels especially profound following the recent passing of his wife, Catherine “Cathy” Barrett. Together, Harry and Cathy shared a life devoted to advancing science and education. Their establishment of the Harrison H. and Catherine C. Barrett Endowed Chair in Optical Sciences for Cancer Imaging, currently held by Professor Lars Furenlid, ensures that their shared commitment to using science in the service of patients and society will endure.
Those who knew Harry will remember not only his intellect and accomplishments, but also his kindness, humility, and unwavering dedication to mentorship. His absence leaves a deep void, yet his example and his work will continue to guide our department and the global imaging community.
Our thoughts are with Dr. Barrett’s family, friends, and all who knew and loved him. Information regarding memorial events will be shared as they are made available.