Perfusion-ventilation CT via three-material differentiation in dual-layer CT: a feasibility study

Area of Science:

• Medical Imaging
• Radiology
• Computed Tomography

Background:

• Dual-Energy Computed Tomography (DECT) allows material differentiation and quantification.
• Current DECT typically differentiates two materials, like iodine and soft tissue.
• Ventilation-perfusion examinations often require two contrast agents, necessitating three-material differentiation.

Purpose of the Study:

• To develop and validate a method for three-material differentiation in DECT.
• To enable simultaneous visualization of xenon ventilation and gadolinium perfusion in a single CT scan.

Main Methods:

• A dual-layer CT scanner was used on a landrace pig.
• Three scans were performed: native, xenon ventilation only, and xenon ventilation with gadolinium perfusion.
• An in-house algorithm performed tissue segmentation and two-material decomposition for xenon/soft tissue and gadolinium/soft tissue.

Main Results:

• The method successfully differentiated xenon and gadolinium, generating density maps.
• Summation of density maps allowed for three-material differentiation (xenon/gadolinium/soft tissue).
• Phantom studies demonstrated highly accurate quantification of xenon and gadolinium (r > 0.999).

Conclusions:

• A novel approach enables three-material differentiation using DECT.
• This technique allows for simultaneous visualization of ventilation and perfusion in a single scan.
• The method shows high accuracy for material quantification, advancing clinical applications.