University of Otago medical graduate Dr Andrew Greensmith, now a Melbourne-based plastic surgeon and consultant at the Royal Melbourne Children's Hospital, played a leading role as part of the surgical team that recently separated the conjoined Bangladeshi twins, Krishna and Trishna. Reporter John Gibb talked to him about the challenges of the landmark operation, which was the culmination of two years of painstaking medical preparation.
The consequences could have been "catastrophic" if the initial separation of the conjoined Bangladeshi twins, Krishna and Trishna, had not gone to plan, Dr Andrew Greensmith, one of the key plastic surgeons involved in the landmark operation, says.
An Auckland-born New Zealander, Dr Greensmith completed an MB ChB at the University of Otago in 1993, studying initially in Dunedin and completing his Otago clinical studies in Christchurch.
He later completed postgraduate training in surgery in Christchurch and Auckland, becoming a Fellow of the Royal Australasian College of Surgeons in 2001.
He has also undertaken further surgical training and studies abroad, in Mexico, France and Britain.
Dr Greensmith, now based in Melbourne, Australia, made the first incision in the marathon 31-hour operation to separate the twins at Melbourne's Royal Children's Hospital, giving them the chance to lead separate lives.
And he was also closely involved when the twins were first separated surgically during the complex procedure.
"Yes, I was holding both heads at the moment of separation - a surreal experience and a mix of relief and elation but knowing that we then needed to immediately repair the massive defects.
"For the twins the difference is life and death - a life together would have been fatal within some months or years. They are now ready for a life as individuals with normal potential to contribute to society and normal life expectancy.
"It has definitely been the pinnacle of my career so far and an absolute privilege to be undertaking such a procedure and to be part of the team in the last two years."
The experience has also reaffirmed some important life lessons.
"My father, who is a dentist in Auckland, always taught me that in life much more is gained in terms of personal development from giving rather than receiving.
"This case is the perfect example - the support before and after the operation and the gratitude extended to us by the carers has been overwhelming and this experience will change us all."
Among the challenges faced by the surgical team was the poor health of the now 3-year-old children who had arrived in Australia from Bangladesh in a rather perilous state.
"They were moribund and dying because of how they were sharing their circulation through their blood vessels connecting their brains - one was pushing the other into heart failure."
Another huge challenge was the complexity of the way the twins were joined: "the sheer surface area, the size of a small dinner plate on each and the various types of tissue that make up that - brain, brain lining (dura), hard tissue (bone) and soft tissue (skin with scalp hair and fat and fascia of the scalp)".
"What we did to fix this had to work well the first time or else the result would have been catastrophic.
"As plastic surgeons when we face complex problems we often look back to the philosophies of Sir Harold Gillies, the father of modern plastic surgery and an Otago graduate who worked during both world wars in the UK.
"He stated you must always have a lifeboat for every operation, i.e. a plan B if plan A is not working.
"We had plan A, B, C, and D.
"Luckily plan A worked fabulously well - plan B would have been to add skin grafts to any areas we could not close, plan C to bring in some other [skin] flaps from locally in the neck or back to close other areas.
"Then plan D would have been to use more distant tissue and transfer it by microsurgery moving a sheet of muscle with its blood vessels and join it to blood vessels in the scalp, neck/face.
"We call this type of plan a reconstructive `ladder' with each `rung' being our plan A, B etc."
The operation went on longer than expected, with some Australian media outlets saying it was initially expected to run for only 16 hours.
But Dr Greensmith says he was not surprised by the extra time needed.
"In fact, I personally anticipated more like 24-30 hours and had cancelled two days of private practice to accommodate this.
"We are used to complex operations in plastic surgery and neurosurgery taking longer than expected."
He noted that he had done a year of neurosurgery training in Auckland and now regularly combined on cases with another New Zealander, neurosurgeon Allison Wray, with whom he had trained.
"My philosophy is that speed is not always of the essence.
"We are more goal-focused - extra time spent can make all the difference.
"This is the same attitude my surgical mentors in New Zealand, Mexico, France and Australia have taken - this `surgical stamina' is vitally important.
"If things in plastic surgery are not right at the end of the operation we think nothing of taking the stitches out and getting it right before we finish.
"Young trainees often find this difficult as they assist us in the operating theatre but it is one of the most important things they can learn.
"Physical fitness and emotional wellbeing is also important. I have a very supportive wife and two lovely children who were a major part of my support team during these two years.
"I apologised to my son who is 11 for missing two of his football training sessions this week as I had not missed one for three years."
Dr Greensmith says he misses life in the South Island "incredibly" and still keeps in touch with surgical colleagues in Christchurch.
During his early years in Auckland he attended King's School and then Westlake Boys' High School.
His father was an Otago University graduate in dentistry and he was proud to follow in that tradition.
"I believe that an Otago degree is a significant factor in helping me to face these sorts of challenges - the culture of the university seemed always one of striving for excellence."