Researcher(s)
- Joaquina Somma, Chemical Engineering, University of Delaware
Faculty Mentor(s)
- Catherine Fromen, Chemical & Biomolecular Engineering, University of Delaware
Abstract
The anatomy of upper-airways varies throughout childhood, which drives different deposition patterns within the upper-airway regions (Kolewe et al. AAPS PHarmSciTech 2023). Since tonsillitis is one common disease in childhood and causes temporary swelling of the tonsils, it is relevant to study how the size of the tonsils affects the deposition of aerosolized medicine. In order to satisfy this need, this work develops an experimental platform using 3D printing to correlate the tonsil size to the deposition of aerosolized therapeutics in upper-airway pediatric models. Tonsil size is categorized by the Brodsky scale, which compares the distance between tonsils against that of the walls of the airway without tonsils. Each category in this scale is referred to as a grade, where a model with less than 25% difference in distance is referred to as grade 1, 26-50% is a grade 2, 51%-75% is a grade 3, and is a grade 4. In this work, CT scans from pediatric models with various tonsil grades were used to create 3D printable models that were split into three different sections according to their placement with respect to the tonsils: top (above tonsils), middle (tonsil area), bottom (below tonsils). After models were split, locking mechanisms were added to ensure easy reassembly, and parts were printed. Nebulized doses of a fluorescent tracer (Rhodamine-B) were administered through the model under a fixed flow rate (~30 L/min); deposition in the different areas, and particle size were studied. Preliminary results show that for a grade 1 model, around 50% of the nebulized dose is deposited on the top part of the upper-airway, 31% deposited on the tonsil area of the model, and 5% deposited on the bottom part. Future studies will continue these experimental evaluations to build a correlation between local deposition and tonsil grade.