COMPARISON OF RADIOGRAPHY, MYELOGRAPHY AND COMPUTED TOMOGRAPHY FOR THE EVALUATION OF CANINE VERTEBRAL AND SPINAL CORD TUMORS IN SIXTEEN DOGS

Radiographic, myelographic and computed tomographic (CT) studies from sixteen dogs with histologically diagnosed vertebral or spinal cord neoplasia (seventeen lesions) were retrospectively evaluated. Radiographs were compared with CT images to evaluate vertebral bony changes (bone production, lysis or both). Myelographic and CT images were evaluated to separate lesions into one of three categories, extradural, intradural/extramedullary, or intramedullary. These findings were compared to histologic tumor type from surgical or necropsy samples. Histologically, seven lesions were vertebral tumors and were classified as extradural lesions; ten lesions were spinal cord tumors of which eight were classified as intradural/extramedullary and two as intramedullary. Using CT, the amount of bony change associated with extradural lesions was greater than or equal to the amount of bony change visualized using radiographs. Myelography more correctly differentiated between intradural/ extramedullary and intramedullary lesions than did CT, although three open diagnoses detracted from the CT results. This study suggests that when evaluating extradural lesions, the amount of bony change was better visualized using CT than survey radiographs. Myelography was better when compared to CT for classifying spinal cord lesions, however, standardization of the CT imaging protocol may help determine the specific clinical indications for using CT in dogs with suspected vertebral or spinal cord tumors.