Radiosurgery of Spinal Lesions

Spinal vascular malformations and spinal tumors have been treated with the use of image-guided frameless stereotactic radiosurgery.^[62] Precise delivery of high-dose radiation limits the dose that would be delivered to normal adjacent tissue and improves morbidity.

Cervical vertebrae can be imaged clearly by x-ray cameras, and lesions are referenced to CT images. The thoracic and lumbar areas have denser bodies that are more difficult to image and provide poor contrast with surrounding tissue. To overcome this limitation, additional radiographic landmarks are implanted percutaneously. Implantation of fiducial markers can be done in the operating room under conscious sedation. These fiducial markers are placed percutaneously under fluoroscopic guidance. Three fiducial markers are required to define any point in three-dimensional space. A fourth is placed for redundancy in case one moves. These fiducial markers are fixed to bony landmark laminae or facets and have a fixed relationship with the bone in which they are implanted. They allow accurate localization for stereotactic radiosurgery.