• Completed medical studies and graduated from the Medical Faculty of Kaunas Medical Institute (currently Lithuanian University of health Sciences) in 1986
  • 1986–1987 – completed core speciality training of surgery in Klaipėda City Hospital (currently – Klaipėda University Hospital)
  • 1988 – surgeon qualification
  • 1991 – internship at Blekinge Hospital, Karlskrona, Sweden
  • 1993 – internship at Russian Surgery Centre, Moscow
  • 2003 – internship at Mahidol University Siriraj Hospital, Bangkok, Thailand
  • 2005 – internship at Copenhagen University HospitalHerlev, Denmark
  • 2005 – internship at Aarhus University Hospital, Aalborg, Denmark
  • 2006 – internship at Tata Memorial Cancer Center, Mumbai, India
  • 2006 – internship at Tehran University and Mehr Hospital in Tehran, Iran
  • 2006 – The International Federation of Obesity Surgery (member of IFSO) World Congress in Sydney, Australia
  • 2008 – IFSO World Congress in Buenos Aires, Argentina
  • 2010 – IFSO World Congress in Long Beach, California, USA
  • 2014 – World Congress of Endoscopic Surgery in Paris
  • 2015 – International Colorectal Surgery Congress in Seoul


  • Member of the International Federation of Obesity Surgery (member of IFSO)
  • Chairman of the Board of Lithuanian Bariatric (Obesity) Surgery Association since 2016
  • Member of the society of International Society of University Colon and Rectal Surgeons (ISUCRS)
  • Member of the Lithuanian Colorectal Surgery Association
  • Member of theLithuanian Association of Surgeons
  • Member of theboard of Klaipėda Association of Surgeons


Doctor Nerijus Kaselis is invited to participate in complex obesity operations.

  • 2007 – Denmark, Aalborg
  • 2016 – Kazakhstan, Astana


  • Laparoscopic duodenal laceration in 1994
  • Laparoscopic peritoneal adhesions removal surgery for bowel obstruction in 1994
  • Laparoscopic surgery to remove a varicocele in 1995
  • Laparoscopic stone removal from the common bile duct in 1995
  • Laparoscopic hemicolectomy of the right side in 1995
  • Transanal haemorrhoidal dearterialization (THD) in 2007
  • Fully laparoscopic pancreatoduodenectomy (Whipple surgical procedure) in 2007 (5th in the world and 2nd in Europe) (the most complicated abdominal surgery even when employing the classical method – through an incision in the abdomen)
  • Laparoscopic gall bladder removal surgery through a single incision (SILS cholecistektomy) in 2010
  • Laparoscopic obesity surgery through a single incision – sleeve gastrectomy (SILS Sleeve gastrectomy) in 2010 (first in the Eastern European countries)
  • Laparoscopic transverse colon removal surgery through the vagina (NOSE) in 2016 (first in the world)
  • Laparoscopic full stomach removal surgery through the vagina (NOSE) in 2016 (first in the world)
  • Laparoscopic of a gastric tumor removal surgery through the esophagus (NOSE) in 2016