Extracellular Volume Quantification With Cardiac Late Enhancement Scanning Using Dual-Source Photon-Counting Detector...

Area of Science:

• Medical Imaging
• Cardiovascular Imaging
• Radiology

Background:

• Cardiac imaging plays a crucial role in assessing myocardial health.
• Extracellular volume (ECV) quantification provides valuable information about myocardial tissue characteristics.
• Dual-source photon-counting detector computed tomography (PCD-CT) is an emerging technology with potential for advanced cardiac imaging.

Purpose of the Study:

• To evaluate the feasibility and accuracy of cardiac late enhancement (LE) scanning for ECV quantification using PCD-CT.
• To compare ECV quantification methods based on dual-energy (DE) iodine ratios versus single-energy (SE) subtraction.
• To assess the radiation dose associated with the LE scan protocol.

Main Methods:

• 30 patients with severe aortic stenosis underwent a low-dose LE scan using PCD-CT after contrast administration.
• Virtual monoenergetic and DE iodine images were reconstructed from the LE scan.
• ECV was calculated using iodine ratios from the LE scan and by SE subtraction, with 3D analysis of whole-heart myocardial volume.

Main Results:

• ECV quantification was feasible in all patients, with a median LE scan dose length product of 84 mGy·cm.
• The median ECV value was 30.5%.
• DE- and SE-based ECV quantification showed good correlation (r = 0.87) with small mean errors (0.9%) and narrow limits of agreement (-3.3% to 5.0%).

Conclusions:

• Dual-source PCD-CT facilitates accurate ECV quantification via cardiac DE LE scans at low radiation doses.
• Calculating ECV from LE scan iodine ratios eliminates the need for a separate nonenhanced scan, avoiding misregistration issues.
• This technique offers a streamlined and reliable approach for ECV assessment in cardiac imaging.