Inhaled aerosol dose distribution between proximal bronchi and lung periphery

Area of Science:

• Pulmonary medicine
• Pharmacology
• Medical imaging

Background:

• Current inhaled drug delivery assessment relies on generic lung region estimations.
• Patient-specific bronchial topology influences aerosol deposition patterns.

Purpose of the Study:

• To directly measure aerosol dose distribution between proximal bronchi and distal lung.
• To establish a method for precise inhaled aerosol dose assessment.

Main Methods:

• Analysis of scintigraphic lung images from 12 asthma patients.
• Inhalation of 1.5-, 3-, and 6-µm particles at 30- and 60-L/min breathing flows.
• Utilized patient-specific bronchial 'hot-spots' for direct proximal deposition measurement.

Main Results:

• Central bronchial deposition varied significantly with particle size and flow rate (17-52% of lung deposition).
• Aerosols not deposited centrally reached up to 75% of the potential lung area.
• Patient-specific airway topology consistently localized deposition hot-spots.

Conclusions:

• Direct measurement of proximal and distal aerosol deposition is feasible using patient-specific imaging.
• This approach provides a robust platform for inhaled therapeutic aerosol drug development.
• Quantification of dose distribution supports optimized inhaled medicine design.