Spectral photon-counting CT: Image quality evaluation using a metal-containing bovine bone specimen

Area of Science:

• Medical Imaging
• Radiology
• Computed Tomography

Background:

• Metal artefacts significantly degrade image quality in computed tomography (CT).
• Photon-counting detector CT (PCD-CT) offers potential advantages over traditional energy-integrating detector CT (EID-CT).

Purpose of the Study:

• To determine optimal imaging parameters for PCD-CT.
• To compare PCD-CT with EID-CT regarding image quality and metal artefact severity.
• To evaluate imaging of a metal-containing bovine knee specimen.

Main Methods:

• A bovine knee with metallic implants was scanned using PCD-CT (120 kV, 140 kV) and EID-CT (Sn150 kV, 80/Sn150 kV).
• PCD-CT images at virtual monoenergetic 72 keV and 150 keV were analyzed.
• Radiologists assessed bony structure visualization and metal artefact severity; statistical analysis was performed.

Main Results:

• PCD-CT 140 kV 150 keV images achieved the highest image quality scores, outperforming EID-CT Sn150 kV.
• PCD-CT 72 keV images showed lower quality and increased HU value variation.
• Artefact severity analysis revealed no significant difference between scanners.

Conclusions:

• PCD-CT 140 kV 150 keV provides superior image quality for metal-containing specimens.
• PCD-CT performance was comparable or better than EID-CT, even without advanced algorithms.
• PCD-CT is a promising technology for mitigating metal artefacts in CT imaging.