Quantification of pulmonary perfusion abnormalities using DCE-MRI in COPD: comparison with quantitative CT and...

Area of Science:

• Pulmonary imaging and diagnostics
• Cardiovascular and respiratory system research

Background:

• Pulmonary perfusion abnormalities are common in COPD patients and may be reversible.
• These perfusion defects are linked to emphysema development, highlighting the need for accurate quantification.

Purpose of the Study:

• To evaluate the clinical meaningfulness of quantitative perfusion defects (QDP) derived from dynamic contrast-enhanced MRI (DCE-MRI).
• To compare QDP with established markers of COPD severity, including CT-based indices and pulmonary function tests.

Main Methods:

• DCE-MRI scans, CT scans, and pulmonary function tests (PFT) from 83 COPD patients were analyzed.
• Quantitative perfusion defects (QDP) were computed using four methods on DCE-MRI: Otsu's method, k-means clustering, texture analysis, and 80th percentile threshold.
• QDP was compared against visual MRI scoring, CT parametric response mapping (PRM) for emphysema (PRM_Emph) and small airway disease (PRM_fSAD), and FEV1/FVC from PFT.

Main Results:

• All QDP methods strongly correlated with visual MRI perfusion scores (r=0.67-0.72) and CT PRM indices (p<0.001), especially PRM_Emph (r=0.70-0.75).
• QDP closely matched the combined extent of PRM_Emph and PRM_fSAD.
• Moderate correlations were found between QDP and FEV1/FVC (r=-0.54 to -0.41).

Conclusions:

• Quantitative perfusion defects (QDP) from DCE-MRI are clinically meaningful and associated with COPD severity.
• The extent of QDP correlates with the combined CT-derived measures of emphysema and small airway disease.
• QDP quantification using Otsu's method on DCE-MRI is recommended for future COPD clinical studies.