Vacuum phenomena on spinal CT scans and its association with intervertebral disc disease in dogs

Vacuum phenomenon (VP) refers to the presence of gas in joint spaces, including those in the spinal column. The phenomenon is associated with progressive and chronic diseases, such as intervertebral disc disease (IVDD). We reviewed 55 canine spinal CT images for the presence of VP, and studied its association with IVDD to determine the association between the VP and the clinical signs exhibited by the patients at the time of exam. All images were obtained between January 2016 and July 2018, at the Diagnostic Imaging Service of a Veterinary Hospital. Image consistent with VP was observed in 7 (12.7%) of the 55 cases. Of these 7 animals, pain and paresis was reported in 3, pain with plegia in 1, and plegia without pain in 3 dogs. One dog did not have a confirmed diagnosis of IVDD. Further studies with larger samples are still needed to confirm the relevance of this phenomenon in the diagnosis of IVDD in dogs.