Effect of Scan Plane and Arthrography on Visibility and Interobserver Agreement of the Equine Distal Sesamoidean Impar Ligament on Magnetic Resonance Images.

This study explores how different scanning techniques and arthrography, a type of medical imaging, affect the visibility and agreement between observers when looking at the distal sesamoidean impar ligament (DSIL) in horses using magnetic resonance imaging (MRI). It found that sagittal T2w Fast Spin Echo and Short Tau Inversion Recovery images provided the best view of the DSIL and that arthrography helped to improve the visualization.

Background of the Study

• The research stemmed from the fact that evaluation of the DSIL in horses using MRI can be challenging due to its heterogeneity and small thickness.
• Moreover, lameness in horses is often localized to their feet, and moderate to severe changes of the DSIL could only be found via MRI.

Aims and Methodology

• The study sought to identify the ideal sequence and optimal transverse perpendicular angle to best visualize the DSIL during an MRI scan. They also wanted to see how the introduction of arthrography would affect the visibility of the DSIL.
• They used 25 cadaver forelimbs for the experiment and tried multiple sequences: sagittal, frontal, and three different angled transverse planes, both before and after arthrography of the DIPJ.

Results and Findings

• The results showed that visualization of the DSIL was most successful when sagittal T2w FSE and STIR FSE images were used.
• When compared to sagittal sequences, all transverse planes were inferior in terms of DSIL visibility.
• Following arthrography of the DIPJ, the DSIL’s origin’s visibility improved in sagittal T2w FSE sequences, and the agreement between observers increased for the sagittal T2w FSE and STIR FSE images.
• Altering the angle of transverse sequences did not significantly improve the visualization of the DSIL, but the arthrography of the DIPJ did.
• It was also found that subjective influence between different observers existed, but this decreased with DIPJ arthrography.

Conclusion

• The DSIL is best visualized on sagittal T2w FSE and STIR FSE images in low-field MRI.
• Arthrography of the DIPJ aids in the improved visualization of the DSIL. Hence, this technique should be used in future studies relating to DSIL and MRI.