A Simplified Geometric Model to Predict Nasal Spray Deposition in Children and Adults.

A mathematical approach was developed to estimate spray deposition patterns in the nasal cavity based on the geometric relationships between the emitted spray plume and the anatomical dimensions of the nasal valve region of the nasal cavity. Spray plumes were assumed to be spherical cones and the nasal valve region was approximated as an ellipse. The effect of spray plume angle (15-85°) on the fraction of the spray able to pass through the nasal valve (deposition fraction) was tested for a variety of nasal valve (ellipse) shapes and cross-sectional areas based on measured dimensions from pediatric and adult nasal cavities.

In Vitro Assessment of Spray Deposition Patterns in a Pediatric (12 Year-Old) Nasal Cavity Model.

Purpose: Nasal sprays available for the treatment of cold and allergy symptoms currently use identical formulations and devices for adults as well as for children. Due to the obvious differences between the nasal airway dimensions of a child and those of an adult, the performance of nasal sprays in children was evaluated.

Methods: Deposition patterns of nasal sprays administered to children were tested using a nasal cast based on MRI images obtained from a 12 year old child's nasal cavity.