Use of intra-articular carbon dioxide and air for MR arthrography: a feasibility study

Area of Science:

• Biomedical Imaging
• Radiology
• Medical Devices

Background:

• Direct magnetic resonance arthrography (MRAr) typically uses gadolinium-based contrast agents.
• Developing novel, safe, and effective contrast agents for MRAr is an ongoing area of research.
• Gaseous agents offer a potential alternative with different imaging characteristics.

Purpose of the Study:

• To evaluate carbon dioxide (CO2) and air as novel contrast agents for direct MRAr.
• To assess the image quality and artifact generation of gaseous agents in MRAr.
• To compare the efficacy of CO2 and air MRAr with phantom studies.

Main Methods:

• Animal experiments involving intra-articular injection of CO2 and air into pig knee joints.
• MR imaging was performed using various sequences.
• Phantom experiments comparing air, CO2, and nitrogen for signal void and artifact characteristics.

Main Results:

• CO2 and air injections resulted in a signal void, clearly delineating cartilage and adjacent structures.
• Only slight susceptibility artifacts were observed with CO2 and air, similar to nitrogen in phantom studies.
• CO2 MRAr demonstrated high contrast between cartilage, ligaments, and synovium.

Conclusions:

• CO2 and air are effective novel contrast agents for direct MRAr, providing excellent delineation.
• The gaseous agents show minimal artifact generation, making them potentially safe for clinical use.
• CO2 MRAr may serve as an investigational tool for cartilage surface lesions and an alternative clinical contrast agent.