Comparison of cone beam CT and low‐field MRI of the distal limb of 85 horses

Summary Background Cone beam computed tomography (CBCT) and magnetic resonance imaging (MRI) of the equine distal limb under standing sedation are increasingly available, yet there is little published information to guide veterinarians on how both modalities compare to optimise horse management. Objective To describe dual modality CBCT and MRI findings in the equine distal limb of images acquired in the standing sedated horse for clinical purposes. Study design Retrospective descriptive study. Methods Clinical records, CBCT and MRI DICOM images of patients that underwent advanced imaging of the distal limb with both modalities on the same day (April 2024 to April 2025) were reviewed. Key imaging findings were categorised to allow comparison of CBCT and MRI findings. Results Imaging studies of 85 horses met the inclusion criteria, resulting in imaging of 120 foot and 38 pastern regions. Twenty‐four of 85 horses had a primary soft tissue injury that was detected on MRI only. Forty‐four horses had increased STIR signal intensity on MRI within the phalanges or navicular bone. CBCT identified a small sequestration of the distal phalanx that was identified on MRI retrospectively, subsequent to CBCT evaluation. CBCT allowed clearer evaluation of cortical bone, specifically at the margins of the flexor cortex of the navicular bone and the articular surfaces of the phalanges. Main limitations Imaging findings were not verified by a gold standard and are subjective and descriptive. Categorical representation of primary diagnosis was difficult for some horses. The horses evaluated are limited to a mixed referral population of horses in Scotland. Conclusions The primary diagnosis was based on MRI in more horses than on CBCT due to the ability of MRI to identify soft‐tissue injury. Combined MRI and CBCT imaging of the foot can provide additional information in horses with solar penetration or when careful evaluation of the cortical bone is needed.