Mr Nassar has developed an interest in laparoscopic surgery since 1990.
His research topics included; safety and prevention of complications in laparoscopic surgery, optimisation of instrumentation and dissection techniques, one session management of patients with suspected bile duct stones, management of biliary emergencies, training and audit.
Mr Nassar has developed new techniques for laparoscopic treatment of impalpable testes, second look laparoscopy, buried bumper syndrome and optimal operative cholangiography. He organises European and international courses aimed at developing and popularising laparoscopic bile duct exploration, including a mentoring programme for a large number of consultants from the UK and overseas who visit Monklands Hospital for this purpose.
Mr Nassar also supervised postgraduate degrees submitted by surgeons interested in advanced biliary surgery.