The role of intraoperative sonography in reducing invasiveness during surgery for spinal tumors.

The authors describe the ultrasound-guided surgical approach to 20 spinal tumors (13 extramedullary and 7 intramedullary). Intraoperative sonography (IOS) is important to reduce the extent of the laminectomy and dural opening, thus avoiding useless removal of bone structures. In cases of intramedullary tumors, IOS defines the extent of the posterior myelotomy, the presence of syringomyelic cavities caudal and/or cranial to the tumor and the deep extension of the tumor to the anterior cord surface. For these reasons, the routine use of IOS during surgery for spinal tumors reduces the surgical invasivity of this approach. The advantages and limits of the ultrasound-guided spinal surgery and the operative ultrasonographic findings of different spinal neoplasms are discussed.