HIROSHI TANAKA, MASANARI NAKAYAMA, KATSUAKI TAKASE.
Ultrasonography was performed during spinal surgery on two dogs that were suspected of having intramedullary lesions by myelography and magnetic resonance imaging. Ultrasonographically, the pathologic conditions of the spinal canal or cord were adequately imaged during surgery in both dogs. On the basis of ultrasonographic findings, a biopsy was obtained in Patient 1 and removal of the lesion was accomplished in Patient 2. Histopathologic diagnosis was myelomalacia in Patient 1 and spinal nephroblastoma in Patient 2. Intraoperative ultrasonography was demonstrated to be suitable for detecting intradural conditions, and, thus, is valuable for increasing the accuracy of biopsies or completeness of resections of intramedullary lesions.