Mark Tso

Mark On Man Tso was born to the Rev. Canon Paul S.F. Tso, an Anglican minister, and Mrs. Amy Hoh Tso, principal of the True Light Elementary School, in Hong Kong, on October 19, 1936. His childhood was marked by the advent of World War II, during which his family fled to Guilin, China, to stay ahead of the Japanese forces. He subsequently graduated high school from St. Paul’s Coeducational College and entered the medical school of the University of Hong Kong. He met Petrina Chan during the summer of 1957 at a college fellowship summer retreat and began dating her. They corresponded frequently while she studied Chinese Literature at National Taiwan University over the next four years. Mark graduated medical school in 1961 and completed an internship at Queen Mary Hospital, Hong Kong, before moving to the United States at the same time as Petrina, in 1963. Upon arriving in the United States, Mark began his surgical internship at the University Hospital, Boston University, while Petrina completed an intensive master’s degree in library science at Emory University. They were married in Baltimore in December 1964, with the assistance of Mark’s brother, Paul, who was on the faculty of Johns Hopkins University. They then moved together to Boston where Mark completed a residency in ophthalmology at Boston University. Mark’s academic career began in 1967 at the Armed Forces Institute of Pathology, Walter Reed Hospital, then in Washington, D.C., under the mentorship of Dr. Lorenz E. Zimmerman, chair of the ophthalmic pathology department. Dr. Zimmerman once asserted that Mark was the very best in experimental ophthalmic pathology during his 30-year tenure. Because of his original experimental work, Mark was recognized as one of the top ophthalmic pathologists in the world. Over his academic career he published over 300 articles and had over 14,000 citations. His unequaled contribution to the understanding of the retina was universally recognized. Mark stated that Dr. Zimmerman’s investment in him and his career was crucial to his success and development as an ophthalmic pathologist. During this period, the Tso’s son (Michael) and daughter (Veleda) came into the world. In 1976, Mark and Petrina made the decision to move to Chicago, where he became a Full Professor of Medicine at the University of Illinois Eye and Ear Infirmary under the leadership of Dr. Morton Goldberg. The collaboration with Dr. Goldberg and the faculty at the Infirmary was critical to Mark’s development as a researcher, leader, administrator, and teacher. His growth in each of these roles was foundational to what God had planned for him later in his life. As a researcher, he was highly successful at attaining NIH grants and recruited first-rate fellows from around the world to work and learn in his laboratory. He was given ample opportunities to lead under Dr. Goldberg’s tutelage, and since his research laboratory became expansive while he also directed the Macula Clinic and the Lions of Illinois Eye Bank, he learned to effectively administer both human and financial resources. But all along, his passion was clearly teaching. Dr. Goldberg shared a story where he walked into Mark’s lab and observed him using a teaching microscope that had eight to nine stations(!)—each with a fellow that spoke a different primary language—all learning from Professor Tso in a synergistic, collaborative manner. These fellows went on to be leaders, professors, and researchers in their home countries after their training with Professor Tso. Then, a door opened for Mark to begin something entirely new, leveraging the national and international recognition that he had earned as a researcher and educator. He was asked to become the Founding Chair of the first academic department of ophthalmology in the country of Hong Kong—uniting academic institutions (The Chinese University of Hong Kong and the University of Hong Kong) and eye care at hospitals and clinics throughout Hong Kong. Therefore, in 1994, Mark and Petrina moved to Hong Kong to live and work for the next five years. This bold and courageous decision to leave the comfort and stability of Chicago led to opportunities they had never imagined. Mark often said that this move began the most productive season of his life as he started to build programs and institutions—as well as developing people and ophthalmology—around the world. Developing an academic department in an entire country with many different entities was a monumental task, and it taught Mark a tremendous amount about leadership, administration, and politics. During his time in Hong Kong, Mark became Vice President and subsequently Director of Education of the International Council of Ophthalmology. These positions opened the door to influence the development of ophthalmology all over Asia, Australia, South America, and Africa, as well as throughout the traditional powerhouses of North America and Europe. Michael remembers his dad beaming with joy and pride as he shared the ophthalmology training curriculum that he had formed, in collaboration with colleagues from every continent, designed to upgrade the skills and knowledge of trainees, no matter their country of origin. Working in Hong Kong also deepened his vision for and ties to China. “Professor Cao” (as he was called in China) was the primary fundraiser, designer, and collaborator for the Peking University Eye Center at Beijing Medical University—the first of its kind in China. Officially, he was the Founding Director and Professor of Ophthalmology from 2001–2011. Two programs at the Eye Center that were particularly significant were the Eli Lilly Diabetic Eye Disease Center and the Prevention of Blindness Program, targeting the visually handicapped in poor, rural areas. Throughout his life, Mark cared immensely for “the least of these,” and sought to bring high-quality eye care to those who couldn’t otherwise afford it. In 1999, Mark and Petrina returned to the United States, and Dr. Morton Goldberg generously invited Mark to join him at the Wilmer Eye Institute at Johns Hopkins University, which served as a hub of operations for all his international work, as well as a home base for teaching and collegial collaboration and support. Awards are a way to recognize the efforts of an individual, and sometimes they are a summative way to acknowledge a body of work in research and education. Just a few of Mark’s many awards that highlight his passions include: Faculty of the Year, College of Medicine, University of Illinois at Chicago, 1986; Honorary Professorship of Beijing Medical University, 1988; Friedenwald Award and Lecturer of the Association for Research in Vision and Ophthalmology, 1989; Siu Lien Ling Wong Visiting Fellow, The Chinese University of Hong Kong, 1990; Honorary Doctor of Science from University of Hong Kong, 1995; and the Friendship Award from the People’s Republic of China, 2009. Mark also delighted in giving awards, establishing in China both the Golden Apple Award for Teaching, and the Golden Key Award for Research in Ophthalmology. Recently, the International Council of Ophthalmology (ICO) established the Mark Tso Golden Apple Award for the Middle East/Africa Region. Although Mark’s professional achievements were formidable, anyone who knew him well quickly discovered that faith, family, and the future were integrally part of his daily life and purpose. Family: Mark was always consulting Petrina on every major decision, while at the same time enjoying her delicious ministrations of food and soup. (He loved soup!) He was always concerned for her well-being—physically, financially, and spiritually. He also provided generously for Michael and Veleda’s schooling and life milestones, but most importantly he always had perspective, advice, and counsel to offer for all of life’s endeavors. Mark and Petrina’s profound legacy includes supporting the higher education of all their grandchildren. Mark generously welcomed newcomers into the family with deep engagement and care. Lastly, for 40 years, he and Petrina invested in gathering the entire nuclear family for a weeklong reunion once a year to share, listen, recreate, and enjoy rich fellowship. Reflecting their deeply-held values, they provided these annual opportunities to build and grow family relationships over decades. Faith: Mark’s faith in Christ was deep and wide. He often spoke about needing God’s grace for difficult decisions and to accept physical disabilities toward the end of his life. He sought God’s wisdom through his reading of the Bible, as well as the writings of Henri Nouwen, Anthony DeMello, Thomas Merton, and many others; through listening to the robust teaching of the late Tim Keller; and finally through mentors and friends in his life. He also gave himself tirelessly to the work of the local church by helping to establish the North Shore Chinese Christian Church in Deerfield, IL—one of the first Chinese churches in the suburbs of Chicago—in 1977. He was a committed member of Chinese Community Church in Washington, D.C. (preaching on occasion), and St. Matthew Presbyterian Church in Silver Spring, MD, during different seasons of life. Perhaps most importantly, he sought to live out his values, faith, and integrity in everyday life in the way of St. Francis of Assisi: “Preach the Gospel [good news] at all times, use words as necessary.” Mark wanted everyone to experience hope amid the pain and sorrow of life, and he dedicated his life both practically and spiritually to that end. His son Michael Tso’s Chinese name means literally, “Tso gives hope.” Future: Mark was constantly planning, almost to a fault. As a family, we are deeply grateful that he was always preparing for the future; always thinking ahead for what might be next. As a result, with Mark and Petrina’s assistance, Michael, Veleda, and their children have established or begun their own journeys of vocation and faith. Mark spoke of his own eventual death countless times over the years, and because he was so well prepared, there weren’t any surprises upon his graduation to Glory. Even though consistently future-oriented, he understood in his soul that faith was required in order not to live in anxiety, which was a regular struggle for him. And yet, the words of St. Paul to Timothy were undoubtedly true of Mark: “I have fought the good fight, I have finished the race, I have kept the faith.” Professor Mark O.M. Tso is survived by his wife, Petrina; son, Michael Tso (wife Heidi); daughter, Veleda Tai (husband Michael); grandchildren Francesca Tso, Vivana Tso (fiancé Kyle Aspen), Dawson Tso, Garrison Tso, Ethan Tai, Alina Tai, Phoebe Tanacea, and Ian Tanacea. He is also survived by his brother, Timothy Tso, and sister-in-law, Muriel Tso. He was predeceased by his parents, his brother Paul Tso, and sister-in-law, Linda Tso. As we mourn Mark’s passing, celebrate his welcome into the arms of Jesus, and remember our relationships with him, our wish for you is that “the peace of God, which surpasses all understanding, will guard your hearts and your minds in Christ Jesus” (Philippians 4:7).

Mark Tso

October 19, 1936 - May 24, 2025