Description:
In equine medicine, experience regarding MRI of chronic tendon lesions is limited, andevidence on the suitability of different sequences in 3 T high-field MRI is scarce. Therefore, macroscopicallyhealthy and altered tendons were examined by histology and in 0.27 T low- and 3 Thigh-field MRI, focusing on T1-weighted (T1w) sequences to visualize chronic lesions. In high-fieldMRI, tendons were positioned parallel (horizontal) and perpendicular (vertical) to the magnetic field,acknowledging the possible impact of the magic angle effect. The images were evaluated qualitativelyand signal intensities were measured for quantitative analysis. Qualitative evaluation was consistentwith the quantitative results, yet there were differences in lesion detection between the sequences.The low-field T1w GRE sequence and high-field T1w FLASH sequence with vertically positionedtendons displayed all tendon lesions. However, the horizontally scanned high-field T1w SE sequencefailed to detect chronic tendon lesions. The agreement regarding tendon signal intensities was higherbetween high-field sequences scanned in the same orientation (horizontal or vertical) than betweenthe same types of sequence (SE or FLASH), demonstrating the impact of tendon positioning. Verticalscanning was superior for diagnosis of the tendon lesions, suggesting that the magic angle effectplays a major role in detecting chronic tendon disease.