16 August 2021

Seal of approval for mask innovation

Children needing the help of a machine to keep their airways open when they go to bed could soon be looking forward to a better night’s sleep thanks to an innovative WA Health collaboration.

Royal Perth Hospital-based engineers and a Perth Children’s Hospital (PCH) surgeon have teamed up to create a customised facial mask cushion that fits CPAP and BiPAP machines.

These machines prevent a user’s windpipe from collapsing during sleep by delivering air – via a tube – into a mask that fits over the user’s nose and mouth. The masks supplied by the machines’ manufacturers, however, may fail to provide a good seal, causing air which should be flowing into the child’s airway, to escape.

Leakage from the masks, not only deprives the child of oxygen but can also cause painful pressure sores and dry eye.

PCH ear, nose and throat surgeon Jenn Ha reveals that the mask can become so uncomfortable that the child will simply refuse to wear it, increasing their risk of long-term harm.

In what is believed to be an Australian-first, bioengineers from the Royal Perth Hospital-based Centre for Implant Technology and Retrieval Analysis (CITRA) have teamed up with Dr Ha to pilot the use of 3-D printing technology to create a mask cushion that is tailored to the face of the individual wearer.

CITRA bioengineer David Morrison says the process begins with a scan of the child’s face which can be done in less than five minutes and performed on a hospital ward or during an outpatient appointment.

The CTIRA team then uses the scan to create a digital 3-D replica of the child’s face. This digital replica is used to create a mould for the silicone mask.

Dr Morrison says the reason for creating the mould (rather than 3D printing in silicone directly) is because it is not yet possible to 3D print the softer silicone material.

Dr Ha said that having to sleep attached to a machine could be traumatic enough for a young child, even without the complication of an ill-fitting mask.

“So, to be able to offer the child a mask that is designed especially for them and that will enable them to sleep safely and more comfortably through the night is a huge breakthrough,” she said.

As a result of this pilot project, a bigger trial is now planned that will help fine-tune the mask production process and assess its value across a larger patient population.

It took about a week and cost around $300 to produce the mask during the pilot but Dr Morrison is hopeful that with refinement, that timeframe could get down to as little as two or three days, with costs similarly expected to go down.

At any one time, around 200 children in the public hospital system are currently on CPAP therapy and about 25 per cent of these patients have problems with ill-fitting masks.

Dr Ha approached CITRA with the proposal of producing a custom-fitted mask because she knew of their capability from working with them on previous projects.

Watch a Channel 7 News report (external site) about the project.