Docs get help from virtual hearts

3D computer models based on patient data will help surgeons in decision-making

Nanyang Technological University Associate Professor Cai Yiyu holds a plastic model of a heart as he explains the technology behind the 3D virtual heart his team developed.
Nanyang Technological University Associate Professor Cai Yiyu holds a plastic model of a heart as he explains the technology behind the 3D virtual heart his team developed. PHOTO: NANYANG TECHNOLOGICAL UNIVERSITY

In roughly a year's time, patients at the National Heart Centre Singapore (NHCS) could have scans of their hearts turned into 3D models on a computer screen.

These virtual reality representations of their hearts will be true to life and will also beat as theirs do.

This will let cardiac surgeons make better pre-surgery plans, especially for non-invasive procedures in which the chest is not opened up and doctors perform surgery through inserting a catheter in the patient's leg and navigating it up to the heart.

The 3D models, created from real patient data, can also be used as a teaching tool for young doctors.

To this end, the heart centre is working with researchers from Nanyang Technological Univ- ersity's (NTU) Institute of Media Innovation, which will set up a virtual reality lab at NHCS for surgical planning and doctor training using the virtual hearts.

This comes even as KK Women's and Children's Hospital was reported earlier this month to be using physical 3D-printed models of children's hearts to improve pre-surgical planning for complex congenital heart conditions.

The hospital started doing so about a year ago.

Similarly, Dr Zhong Liang, a principal investigator at NHCS, said that the virtual hearts can improve pre-treatment planning.

"It gives surgeons better visuals for decision-making and also shortens the diagnosis process," he said.

While scanning technology currently can give surgeons images of the heart, the images are in 2D.

Dr Zhong said this means that while surgeons can see problematic areas of the heart, it is hard to perceive depth.

Currently, doctors practise on cadavers or animals, but there are problems with this.

Cadavers do not have blood flow, their muscular structures are damaged and the hearts do not beat.

Surgery on live animals, such as monkeys or pigs, presents another issue - it is expensive and can cost up to $10,000 each.

Another issue is that when surgeons need to "see" where their catheters are going during surgery, they perform fluoroscopy on the patients.

This process uses X-ray dyes and exposes patients to radiation - which is not ideal.

At the same time, it also does not give surgeons a sense of depth.

But Dr Zhong hopes to bring the virtual hearts into the operating theatres to help address these problems and, hopefully, eliminate the need for fluoroscopy.

The collaboration between NTU and NHCS is part of a memorandum of understanding signed in January between the university and SingHealth for a five-year tie-up that pumps up to $300,000 in six joint research projects.

NHCS and NTU are now applying for more funding to set up the virtual reality laboratory and to conduct more research around the project.

The biggest potential for the technology is in children, said researchers, because their peripheral arteries are smaller and the virtual hearts can let surgeons plan a more accurate path for non-invasive operations.

The researchers are looking to run two clinical trials.

A version of this article appeared in the print edition of The Sunday Times on September 25, 2016, with the headline 'Docs get help from virtual hearts'. Print Edition | Subscribe