It is with a heavy heart that I share with you the passing of our friend and colleague on January 17, 2022. For those who did not know Demetrius (fig. 1), he was truly rare in all ways. He exemplified the complete academician: tenacious and meticulous researcher, innovator, mentor, advocate and exceptional teacher. Those of us who were his residents and fellows recall his keen wit, often curt, direct assessment of our technique in the operating theater, as well as his genuine concerns for our academic and personal lives. A giant in the development and application of upper urinary tract endoscopy, he was soft spoken and humble outside of medicine. An omnipotent educator, he tirelessly advanced ureteroscopy to the current state-of-the-art, expanding the skills of urologists worldwide through innumerable workshops, lectures and visiting mentorships (fig 2.).

A few weeks before his passing, I asked Demetrius what inspired his interest in upper urinary tract endoscopy. Without hesitation he recalled the sentinel case performed by his colleague, Ed Lyon, at the University of Chicago where the first distal ureteral tumor was treated ureteroscopically.¹ It was this collaboration with Ed Lyon and Jeff Huffman that lay the foundation for his future academic life.

When he arrived in Philadelphia in 1983 I was a medical student in the adjacent basic science laboratory in the department of urology at Thomas Jefferson School of Medicine. As was his nature, he promptly recruited and inspired me to follow in his footsteps. Over the next 39 years our relationship evolved from student to resident, to colleague and collaborator, and finally to lifelong friends. Teaching colleagues was integral to his academic mission. In January 1989 he led a team from Jefferson to Asyût, Egypt (fig. 3), where over 3 weeks we completed over 90 procedures with Mohammed Shalaby and Magdy El-Akkad, which included the first laser lithotripsy cases performed with the French pulsed dye laser. In December 2021 I returned to Egypt as an AUA diplomat and through the magic of Facetime, Demetrius was able to rekindle those friendships with local faculty.

Demetrius’ extended family was all of us. Visiting faculty from far and wide routinely were hosted by the Bagleys over the years. On any given summer day you could find my spouse and children on the Bagley’s shore porch with Demetrius and Jackie, and Ilana and Robert Weiss. He cherished his relationships with his alma mater, Yale, and with Jefferson faculties. Each fall Demetrius hosted an annual ritual, a weekend of academic exploration and camaraderie for faculty, nurses and administrative staff, as well as alumni and colleagues, at the seashore in Avalon, New Jersey.

Of his 60 or so residents and fellows, Jeff Huffman and I represent the early years. I tracked Jeff down in Bakersfield, California, where he now practices. We both clearly recalled Demetrius’ meticulous attention to detail and his impeccable grammar and syntax, both having spent many nights refining manuscripts to ultimately meet his standard. This is underscored by his over 400 original papers and textbook chapters. Interestingly, he also was accomplished in veterinary medicine, publishing in their journals and commonly performing ureteroscopy on a variety of animals. I can recall when he performed ureteroscopy, for gross painless hematuria, on a lion at the Philadelphia Zoo, the case ending promptly when the animal awoke during the procedure and wrapped its paw around him.

Demetrius chaired the AUA Ureteroscopy course from 1990 to 2006, and thereafter as chair of this and many other programs I had the honor of hosting my mentor as faculty. He last participated in the fall of 2021, virtually; truth be told, he struggled with his home computer; my fellow was essential in assisting him remotely. As instruments improved and techniques evolved, these and many other courses both nationally and throughout the globe (fig. 4) fulfilled 2 of his missions: raise skills and develop a collaborative spirit—the essence of an AUA diplomat.

Figure 1. Jackie and Demetrius Bagley at the San Francisco AUA (2010).

Figure 2. Demetrius Bagley at the Kyoto World Congress with Richard Babayan (1989).

Figure 3. Demetrius Bagley with Amy Goodman and Michael Grasso in Asyût, Egypt (1989).

Figure 4. Demetrius Bagley with residents at St. Vincent’s Hospital, Melbourne, Australia (1995).

Figure 5. Michael Erhard, Demetrius Bagley and Michael Grasso at the Annual Avalon Urology Symposium (2018).

On a more somber note, 10 years ago he called me after palpating an enlarged axillary node. This led to chemotherapy and a bone marrow transplant. He survived this and returned to teaching. Five years later a new primary led to radical surgery, radiation, chemotherapy and much healing. He survived this second test and hosted the annual Avalon meeting for the next 2 years (fig. 5). Two years ago I examined him; it was something new, aggressive and rare, as rare as he was, with no proven treatment. He was convinced the cumulative ionizing radiation exposure in the operating theater over the years was the culprit and encouraged us all to take heed. In truth, only those of the strongest stock could have survived these personal tests for this long. Throughout these difficult times, a day did not go by where he did not call to inspire a past resident, fellow or colleague. His son Jacques facilitated a phone call from Demetrius the night before he passed. As always, he gave me direct instructions, asking me as his friend to complete a few tasks—basically to keep teaching and carry the baton. We will surely do that and more.

Many thanks to Scott Hubosky, Jeff Huffman and Robert Weiss who helped in my research for this tribute.