[A software tool for analysis and quantification of regional pulmonary ventilation using dynamic...

Area of Science:

• Pulmonary medicine
• Medical imaging
• Quantitative analysis

Background:

• Hyperpolarized helium-3 MRI (3He-MRI) offers unparalleled temporal and spatial resolution for visualizing regional lung ventilation.
• Existing methods lack the ability to quantify dynamic ventilation parameters in absolute physical units.

Purpose of the Study:

• To develop novel software for the quantitative analysis of dynamic ventilation parameters derived from 3He-MRI.
• To present ventilation parameters in absolute physical units for objective assessment.

Main Methods:

• A 2D FLASH sequence acquired 168 coronal projection images during continuous breathing with a bolus of hyperpolarized 3He.
• Postprocessing software was developed to analyze 3He distribution, correcting for lung motion.
• Ventilation parameters including rise time, delay time, 3He amount, and peak flow were calculated and normalized to absolute physical units.

Main Results:

• The software successfully analyzed data from healthy volunteers and patients with lung transplantation and emphysema.
• Pixel-based analysis in healthy volunteers showed homogeneous ventilation parameter distribution.
• Patients with lung disease exhibited distinct regions of poor ventilation on parameter maps.

Conclusions:

• The developed software enables objective, quantitative assessment of regional lung ventilation in absolute physical units.
• The software shows potential for grading and monitoring pulmonary function and therapy effectiveness.
• Further clinical studies are needed to establish the clinical significance of the derived parameters.