Dr. Johnny Hong served as principal investigator and co-investigator in the National Institute of Health (N.I.H.)- funded and other peer-reviewed research studies related to liver diseases and transplantation. His clinical research led to various patient treatment guidelines for cholangiocarcinoma, immunosuppression, transplantation critical care, and transplantation of partial hepatic grafts from live- and deceased (in-situ split) donors. 

Dr. Hong's basic science research focuses on organ resuscitation to mitigate the adverse effects of liver ischemia and reperfusion injury. Through his work in the research laboratory, he invented Regulated Hepatic Reperfusion, which received a patent from the U.S. Patent and Trademark Office in 2020. This liver resuscitation therapy aims to convert marginal quality deceased donor livers to suitable organs for transplantation, reducing the number of patient deaths while on the transplant waitlist.

Dr. Johnny Hong is an expert on the entire spectrum of liver transplantation (including live-donor) and hepatobiliary surgery for adults and children. In addition, he has performed some of the "first" in hepatobiliary surgery, including an innovative liver surgery procedure in a 56-day-old infant.

Dr. Johnny Hong is board certified by the American Board of Surgery. In addition, he is an active member of numerous professional societies and organizations, including his election to Fellowships of the American College of Surgeons and the American Surgical Association.