Reliability of high- and low-field magnetic resonance imaging systems for detection of cartilage and bone lesions in the equine cadaver fetlock.

This study investigates the reliability of two different magnetic resonance imaging (MRI) systems in detecting cartilage and bone lesions in horse fetlocks. The research found that although both systems were highly sensitive, they also produced a significant number of false positives. Independently interpreting a range of pulse sequences may improve the detection rate of these lesions.

Understanding the research objectives

First and foremost, this investigation aimed to test the reliability of two different MRI systems – high and low field – in detecting cartilage and bone lesions in the fetlocks of horses. The underlying hypotheses were:

• Lesions in cartilage, subchondral and trabecular bone of the equine can be accurately detected via high-and low-field MR images with a low frequency of false results.
• Low-Field images are less reliable than high-field images when it comes to detecting cartilage lesions.
• Interpreting the results of different pulse sequences can would increase the detection of cartilage lesions.

Methodology

To conduct this study, the researchers performed high- and low-field MRI on 19 limbs of horses that had been identified with fetlock lameness before they were euthanized. The researchers then used a grading system to score the cartilage, subchondral, and trabecular bone on the MR images and on histopathology – which served as a gold standard or control.

Findings

High-field T2*W-GRE and low-field T2W-FSE images showcased high sensitivity but low specificity for detecting cartilage lesions. In layman’s terms, high sensitivity indicates that the MRI systems were good at correctly identifying the actual positives, though low specificity means that the systems may not be as efficient in you ruling out the negatives.
The researchers observed high sensitivity and moderate specificity for subchondral bone lesions detection. For detecting trabecular bone lesions, the sensitivity was moderate, and the specificity was moderate to high. The low-field T2*W-GRE images, however, had higher sensitivity and specificity than T2W-FSE images for trabecular bone lesion detection.

Conclusions

The study found that using either high- or low-field MRI to detect cartilage lesions could result in a large number of false positives. The subchondral bone lesions exhibited a somewhat high likelihood of false positives compared to histopathology. The researchers found that combining interpretations from different pulse sequences did not increase cartilage lesion detection. The detection of trabecular bone lesions was more reliable than that of cartilage or subchondral bone on both MRI systems.
Overall, the study suggests that the independent interpretation of a variety of pulse sequences may maximize detection of cartilage and bone lesions, but clinicians should remain aware of the potential for false positives and negatives.