Simultaneous high-pitch multi-energy CT pulmonary angiography using a dual-source photon-counting-detector CT: A...

Area of Science:

• Medical Imaging
• Radiology
• Photon-Counting Detector Technology

Background:

• Dual-source CT systems offer high-pitch helical mode (66 ms temporal resolution) to reduce motion artifacts in CT pulmonary angiography (CTPA).
• Multi-energy (ME) mode provides iodine maps crucial for pulmonary embolism (PE) evaluation.
• Current energy-integrating detector (EID) CT cannot perform simultaneous ME and high-pitch acquisition.

Purpose of the Study:

• To evaluate the capability of photon-counting-detector (PCD) CT for simultaneous high-pitch and ME imaging in CTPA.
• To assess the impact of motion on image quality and diagnostic accuracy.

Main Methods:

• A motion phantom simulating respiratory motion was employed.
• Tubes with iodine and simulated thrombus were scanned using separate high-pitch/ME EID-CT and simultaneous high-pitch ME PCD-CT.
• Virtual monoenergetic images and iodine maps were reconstructed; percent thrombus occlusion was measured.

Main Results:

• EID-CT ME scans exhibited significant motion artifacts.
• PCD-CT high-pitch ME demonstrated more stable iodine concentration measurements under motion, with lower standard deviation compared to EID-CT ME.
• PCD-CT high-pitch ME showed good agreement in thrombus occlusion measurements between static and moving conditions, unlike EID-CT.

Conclusions:

• PCD-CT in combined ME and high-pitch mode allows for simultaneous accurate iodine quantification.
• This technique facilitates reliable assessment of intravascular occlusion in CTPA, even with patient motion.