SINGAPORE - When Ms Sophia Chua heard her three-year-old son's liver was failing, she broke down and cried: "I just want to save his life."

The 31-year-old volunteered to donate part of her own liver using a pioneering technique.

Not only was the operation a success, but the less invasive approach meant she avoided being left with a long scar.

A small but growing number of donors in Singapore are being offered the keyhole method, which can seem less frightening.

At present, some potential donors back out after learning that the traditional open surgery technique will leave them with a scar of up to 20cm to 25cm.

It is hoped that the new, minimally invasive approach will save lives by increasing the number of Singaporeans who agree to donate part of their livers.

Ms Chua, a housewife, would have had the open surgery anyway to save her son, but thankfully she did not have to. With the keyhole transplant surgery, the cut made to allow for the extraction of the liver was just 5cm. She also recovered faster.

Her son Xavier, now four, was born with a rare condition known as biliary atresia, where the bile is trapped inside the liver, causing damage and scarring. His condition had deteriorated to the point where he needed a liver transplant.

The operation was performed in August last year, not long after the Government allowed the resumption of elective transplants, which were put on hold when Covid-19 cases were high.

Living donors like Ms Chua who have had this type of surgery leave the operating theatre with just a 5cm to 7cm scar that sits above the pubic region, much like a caesarean section scar.

Compared with open surgery, the keyhole method also leaves the patient with less post-operative pain and a shorter recovery time.

Associate Professor Alfred Kow, a senior consultant at the liver transplantation unit at the National University Centre for Organ Transplantation (Nucot), carried out the procedure on Ms Chua.

Prof Kow introduced the procedure at Nucot in November 2017 after learning the method, known as laparascopic donor hepatectomy, in South Korea. The country is a leader in this field, with more than 500 operations carried out.

Since then, he and the team at National University Hospital (NUH) have performed 15 such transplants, of which eight involved child recipients. Over at the SingHealth Duke-NUS Transplant Centre, the first laparoscopic donor hepatectomy for living donor liver transplant was performed in March 2019.

Prof Kow said the minimally invasive method is "technically demanding" and must be performed by highly proficient surgeons with experience in both the new and the usual technique. In a paediatric living donor transplant, where an adult donor is giving away a part of the organ to a child, surgeons will cut the left section of the liver. This provides a smaller portion of the liver than is needed for an adult transplant, which involves cutting the bigger right lobe.

Prof Kow is hopeful that the increased success with this method will encourage more people to step forward as donors.

As at June last year, there were 45 people on the waiting list for a liver, unchanged from the end of 2019. The average wait time for a liver from a deceased donor is nearly 20 months, and some people die while waiting. Patients who need living donors usually ask friends and family, though in recent years some have also turned to social media.

Since 2018, NUH has seen an average of 30 to 50 patients a year with either liver failure or liver cancer. Around 80 per cent require liver transplants.

Prof Kow said demand is likely to rise. "While we see many cases of patients with chronic liver disease due to hepatitis B, C and alcoholic liver disease, there is a significant increase in patients with non-alcoholic fatty liver disease who progress to liver failure needing transplantation," he added. "This is partly due to the high incidence of metabolic diseases such as hypertension, hyperlipidaemia and diabetes in our population."

The laparascopic liver transplant operation takes about four to five hours, and the living donor will typically need a three-to-four-day stay in hospital. Their liver will usually grow within a month of donation, and be back to the original size in about three months, said Prof Kow.

To play it safe for now, not everyone will be offered the minimally invasive method, where the surgeon will perform the division of the liver through small upper abdominal incisions ranging from 5mm to 10mm, he said.

Around 10 to 20 per cent of donors may be suitable to undergo this method. Donors whose liver graft is too large or who are overweight and have limited space in the upper abdomen will not be offered it.