A C-arm photon counting CT prototype with volumetric coverage using multi-sweep step-and-shoot acquisitions.

Area of Science:

• Medical Imaging
• Radiological Technology
• Photon Counting Detectors

Background:

• Current clinical C-arm interventional systems rely on flat panel detectors (FPDs) for cone-beam CT (CBCT) imaging.
• FPD-CBCT offers volumetric coverage but lacks sufficient low-contrast detectability for specific interventional needs.

Purpose of the Study:

• To develop and evaluate a C-arm photon counting detector (PCD) CT system using a step-and-shoot acquisition method.
• To enhance tomographic imaging performance for interventional procedures.

Main Methods:

• A cadmium telluride-based PCD was integrated into a biplane C-arm system alongside an FPD.
• A synchronized motorized patient table facilitated a step-and-shoot data acquisition strategy with multiple C-arm sweeps.
• Experiments utilized physical phantoms, a human cadaver head, and an in vivo swine subject, comparing results with FPD-CT under matched conditions.

Main Results:

• PCD-CT images demonstrated lower noise and superior visualization of low-contrast lesions compared to FPD-CT.
• Improved visibility of small iodinated blood vessels and finer structures was achieved with PCD-CT.
• No geometric distortion artifacts were observed in the multi-planar PCD-CT images.

Conclusions:

• This work presents the first successful demonstration of high-quality, multi-planar PCD-CT imaging using a rotating C-arm gantry.
• The developed system shows significant potential for improving diagnostic capabilities in interventional radiology.