Dr Sein Lwin completed his neurosurgical residency and fellowship training at Queen Hospital, London, UK. He completed his undergraduate studies at The University of Medicine, Yangon, Myanmar in 1994, and received a Masters of Medicine (General Surgery) from the same University in 1999. He worked as a consultant general surgeon and neurosurgeon in Myanmar before he joined National University Hospital, Singapore. He also completed the Masters of Medical Science (Surgery) at the National University of Singapore in 2006.

He completed his fellowship training in endoscopic endonasal pituitary and open skull base surgery at the University of Pittsburgh, USA. His research was focused on minimally invasive surgery and endoscopic surgery for skull base tumours and evaluating patient outcomes in functional recovery following these surgeries and more recently on functional outcome improvement in minimally invasive spine surgery for spinal cord tumours.

Dr Sein Lwin set up the first centre of endonasal endoscopic skull base surgery with ENT colleagues at the National University Hospital in 2012 and operated on over 300 complex skull base tumours and pituitary tumour cases from Singapore and other regional countries for more than 10 years.