Non-invasive ventilation (NIV) is assisted respiratory support delivered via facemask for people with chronic respiratory failure. Commercial NIV masks are available but masks that fit well are difficult to find for children who have small or asymmetrical facial features. Compromised ventilation can have significant health and quality of life impacts for patients and their families.

Previous development of 3D printed custom-made masks to improve comfort, fit and performance of NIV for children revealed that in 45% mask-fit was compromised by poorly-fitting headgear (Willox 2020).¹ Parents report that headgear is of ‘paramount’ importance for mask-fit.

Design concepts and materials for a custom-made modular headgear were refined using patient and parent/carer feedback until a final prototype was reached. The custom-made headgear was evaluated against a comparator mass manufactured stock headgear using adult volunteers using pre-set levels of headgear strap tension (100g, 200g and 300g). Air leak was demonstrated using leak data from a Nippy Junior Plus ventilator and pressure was measured using a Tekscan F-Socket 9811 pressure sensor array.

Air leak measurements at medium tension (200g) were 82 l/min for custom mask/custom headgear, 69 l/min for stock mask/custom headgear and 79 l/min for stock mask/stock headgear. Pressure readings at the nasal bridge at medium load (200g) were 86 g/cm2 for custom mask/custom headgear, 53g/cm2 for stock mask/custom headgear and 123 g/cm2 for stock mask/stock headgear.

At medium tension, a stock mask with customised headgear was the optimum combination. 3D printing of silicon is in its infancy therefore 3D custom-made mask technology is evolving; however implementation of custom-made headgear may result in significant patient benefit.

Reference

1. Willox M, Elphick HE, et al. Custom-made 3D printed masks for children using non-invasive ventilation: a feasibility study of production method and testing of outcomes in adult volunteers. J Med Eng Technol. 2020 Jul;44(5):213–223.