After graduating from the Nippon Veterinary and Life Science University in 2001, Dr. Torisu spent a year as a resident physician at the university before advancing to graduate school at the same institution. Under the guidance of Professor Makoto Washizu, he conducted research on portal systemic shunts and obtained his doctoral degree in 2006. Until March 2009, Dr. Torisu established a liver disease outpatient clinic as a special graduate student at the Nippon Veterinary Medical Center, treating approximately 500 cases of liver disease and performing nearly 300 surgeries for PSS (portal systemic shunt). From May 2009, he has been serving as an associate professor at the Miyazaki University Faculty of Agriculture Affiliated Animal Hospital, providing surgical and medical treatment for gastrointestinal diseases on a daily basis and treating over 1,000 referral cases annually. Since October 2016, as a professor at the same affiliated animal hospital, Dr. Torisu has been dedicated to clinical practice, research, and education. Currently, he has performed over 1,000 surgeries for PSS, and recently, he has been performing laparoscopic surgeries for PSS. In April 2021, Dr. Torisu relocated to his current position at the Rakuno Gakuen University, where he serves as a professor in the Companion Animal Surgery Unit and head of the Oncology Department at the Affiliated Animal Medical Center. Since May 2022, he has been appointed as the director of the Affiliated Animal Medical Center.