Tivers MS, Mahoney PN, Baines EA, Corr SA. Department of Veterinary Clinical Sciences, Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield, Hertfordshire AL9 7TA, UK. JSAP 2009 Jul 50 7 324-32 OBJECTIVE: To assess the usefulness of computed tomography arthrography of the stifle in diagnosing meniscal tears in dogs with cranial cruciate ligament insufficiency. METHODS: A prospective clinical study was performed. Dogs were included if they had evidence of cranial cruciate ligament insufficiency or persistent or recurrent lameness following surgery for cranial cruciate ligament insufficiency. Dogs were sedated for a computed tomography scan of the affected stifle, orientated in the dorsal plane. A survey computed tomography scan was followed by a computed tomography arthrogram. A stifle arthrotomy was performed, and the surgical findings were recorded. The computed tomography scans were reviewed by three blinded reviewers, and the results were compared to the surgical findings. RESULTS: Twenty-one computed tomography arthrograms from 20 dogs were included. At surgery, damage to the medial meniscus was identified in 14 stifles. Initial interpretation of computed tomography arthrography images was 57 to 64 per cent sensitive and 71 to 100 per cent specific for diagnosing medial meniscal injuries. Interpretation of the images on retrospective analysis was 71 per cent sensitive and 100 per cent specific, with an accuracy of 0.857. CLINICAL SIGNIFICANCE: The accuracy of stifle computed tomography arthrography for the diagnosis of tears to the medial meniscus was found to be good. It is a minimally invasive and repeatable technique, which does not require general anaesthesia or specialist training to obtain the images. The ability to reliably diagnose meniscal injury without the need for surgery may be advantageous, particularly in dogs which had previously had surgery for cranial cruciate ligament insufficiency.