Detection of Pulmonary Embolism Using a Novel Dynamic Flat-Panel Detector System in Monkeys

Area of Science:

• Medical Imaging
• Pulmonary Physiology
• Cardiovascular Imaging

Background:

• Dynamic chest radiography (DCR) is a novel technique utilizing flat-panel detectors (FPDs) for pulmonary function assessment.
• FPD-based DCR enables evaluation of pulmonary artery blood flow without the need for contrast agents.
• This study explores the utility of FPD-based DCR in detecting physiological blood flow changes and pulmonary embolism (PE).

Purpose of the Study:

• To investigate the capability of FPD-based DCR in measuring physiological pulmonary blood flow variations.
• To assess the efficacy of FPD-based DCR in detecting pulmonary embolism (PE) in a preclinical model.
• To evaluate the impact of postural changes on pulmonary blood flow using DCR.

Main Methods:

• Dynamic chest radiography (DCR) was performed on 5 monkeys using a flat-panel detector (FPD).
• Regions of interest (ROIs) in lung fields measured maximum pixel value changes per cardiac cycle.
• A pulmonary embolism (PE) model was induced, and lung pixel values were compared in supine and standing positions.

Main Results:

• Lung pixel value changes (∆pixel value) exhibited a cyclical pattern synchronized with the electrocardiogram.
• ∆pixel values in the upper lung fields decreased in the standing position compared to the supine position.
• In the PE model, occluded lung areas showed reduced ∆pixel values, while contralateral lung areas showed increased ∆pixel values.

Conclusions:

• A flat-panel detector (FPD) can detect postural alterations in pulmonary blood flow.
• FPD-based DCR successfully identified reduced pulmonary blood flow caused by pulmonary artery occlusion in a monkey model.
• This technique shows promise for non-invasive detection of pulmonary blood flow abnormalities.