FIGURE 3.

Elements of a computational fluid dynamics–based complete‐airway stochastic individual pathway model for comparison of regional MDI and DPI drug delivery including (a) computational models of the inhaler flow pathways and conducting airways, (b) prescribed SD and QD inhalation profiles, (c) experimentally measured particle size distributions at different tested flow rates, and (d) deposition fractions in specific airway regions as a percentage of aerosolized drug. DPI, dry powder inhaler; MDI, metered dose inhaler; MMAD, mass median aerodynamic diameter; MT, mouth–throat; Q, flow rate; QD, quick and deep; SD, slow and deep; TB, tracheobronchial. Reprinted by permission from Springer Nature: Springer Nature, Pharmaceutical Research, Comparing MDI and DPI aerosol deposition using in vitro experiments and a new stochastic individual path (SIP) model of the conducting airways Longest et al. ⁴³