The effect of CT and MRI with and without arthrography on the appearance of the feline carpal ligaments

BACKGROUND: The current diagnosis of feline carpal injuries is based on radiographic examination including stress views and computed tomography; however, these techniques do not allow for direct evaluation of the carpal ligaments. The purpose of this cadaveric study was to assess the ability of CT arthrography (CTA) and MR arthrography (MRA) to provide this information using a single contrast mixture. A protocol for intra-articular injection of the feline carpus was also described. A contrast solution containing gadolinium and iohexol with a 50% gadolinium solution (Magnevist—gadolinium 0.5 mmol/mL diluted to a 0.05 mmol/mL solution) and 50% of iodine (Iohexol—iodine 300mgI/mL) was injected into the antebrachiocarpal and middle carpal joints of feline carpi using fluoroscopic guidance. RESULTS: CTA allowed for identification of intra-articular ligaments and the silhouette of select extra-articular ligaments when there was adequate joint distension, however it was not considered to be superior to MRI. MRA allowed for improved identification of the dorsal radiocarpal, accessorioulnocarpal, accessorioquartile, short ulnar and short radial collateral ligaments. CONCLUSION: In this ex-vivo study, combined CTA and MRA enhanced the appearance of the feline carpal ligaments and may provide a foundation for future studies in the diagnosis of carpal injuries. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12917-022-03463-6.