Assessing lung function using contrast-enhanced dual-energy computed tomography for potential applications in...

Area of Science:

• Medical Imaging
• Radiation Oncology
• Pulmonary Physiology

Background:

• Increasing interest in lung function imaging for radiation therapy.
• Goal to reduce post-radiation toxicities.
• Need for reliable functional data from imaging.

Purpose of the Study:

• Retrieve reliable functional information from contrast-enhanced dual-energy CT (DECT).
• Apply DECT-derived functional data in radiation therapy planning.
• Compare DECT functional data with single-energy CT (SECT) and SPECT/CT.

Main Methods:

• Retrospective analysis of 5 lung cancer patients.
• Acquired contrast-enhanced DECT and SPECT/CT scans.
• Processed DECT into iodine concentration maps to determine perfused blood volume.
• Computed differential lung function per lobe for DECT, SECT, and SPECT/CT.

Main Results:

• Strong correlation (r=0.91) between DECT and SPECT/CT for differential lung function per lobe.
• Moderate correlation (r=0.46) between DECT and SECT.
• DECT showed a 7% mean difference compared to SPECT/CT for left lung function.
• Identified nonfunctional lung areas via iodine concentration drops.

Conclusions:

• Successfully extracted iodine concentration maps from DECT for lung subvolume function calculation.
• DECT shows good agreement with SPECT/CT for functional lung assessment.
• Integrating DECT functional data into radiation therapy planning can optimize dose and spare healthy lung tissue.