Abstract
Background: A good seal is regarded as critical factor of face-masks for efficient inhaled drug delivery. Dead space, contour, flexibility and acceptance are also important.
Objectives: Evaluate anthropometric data and CAD-simulation to optimise face-masks for inhalation.
Methods: Basic anthropometric data of faces and heads from 32 children (age 1,1-3,5 yrs) were determined with measuring tape and calliper. Data were compared to existing literature data. Frontal and profile photos were taken with and without a mask prototype. Photogrammetry was used to generate a 3-D CAD-database comprising the anthropometric and mask related information. The complex interactions between face and mask were then simulated and geometric data for optimised mask design determined. In a subsample (n=8) of the study population, fit of the optimised masks was visually controlled.
Results: Basic anthropometric data of the sample population agreed well with literature values, proving the study population to be representative. CAD-simulation identified the 2D-tightness geometry as inappropriate and was changed to a 3D-shape with soft lip seals. Dead space could be minimised yet leaving enough space for the nose to keep the mask comfortable. Design according to the CAD-simulation led to an optimised fit of the face mask. Dimensions went very well with the children's face structures. Enclosure of mouth and nose were both collision-free and space-saving.
Conclusions: Complex interactions between face and mask could be successfully simulated with a CAD-database. This helped to design face masks (PARI SmartTouch) which now allow for less leakage, more comfortable fit and minimised dead space - supporting efficient aerosol delivery.
- © 2011 ERS
