A toddler from Antrim, Northern Ireland is first in the world to receive an organ transplant using 3D technology.

When Lucy Boucher was born, she suffered from heart failure, causing her kidneys to significantly lack oxygen and shut down. Lucy was then faced with a lifetime of dialysis treatments.

Her parents brought her to Guy's and St Thomas' and Great Ormond Street Hospital, where doctors recommended her to undergo a kidney transplant. Her dad, Chris, was a perfect match for donation, but there was one problem. How could a big, adult kidney fit into Lucy's small abdomen?

That's when 3D printing technology came into the picture. Doctors produced models of Chris' kidney and Lucy's abdomen to determine how the organs would fit together. The intervention would greatly help doctors plan out the very complicated procedure and reduce risks.

"When I first saw the models I was taken aback by the level of detail that's in them," said Chris. He added that it really helped him create an idea of what is going to happen during the operation.

Chris was surprised at how big his kidney was and wondered how it could possibly fit into his daughter.

Despite the initial shock, he was relieved that the doctors could perform such detailed planning prior to the surgery. He said it eased his concerns and "was hugely reassuring."

To carry out the 3D print procedure, both Chris and Lucy underwent CT and MRI scans to get the precise measurements of their organs. The 3D printer then produced a liquid plastic model to mimic the size and density of the body parts.

With the organ models at hand, the surgeons were able to assess the possible outcomes of the procedure and rehearse each step of the surgery.

On Nov. 24, 2015, the doctors finally transplanted Chris' kidney to Lucy. The operation lasted for four hours.

Now, Lucy is doing great and both she and Chris are recovering well. In fact, Lucy may be attending nursery school late this year.

"The transplant is life-changing for Lucy," says her mother, Ciara, a teacher.

Lucy's operation is the first in the world to use 3D printing technology to transplant an adult kidney to a child recipient.

Pankaj Chandak, a transplant registrar at the hospital, says the most important advantage of using 3D printing is patient safety. The technology paves the way for informative and hands-on planning, providing doctors the most critical details they need to know prior to the operation.