Background:
The role of stereotactic radiosurgery for treatment of intracranial lesions is well established.Its use for the treatment of spinal lesions has been limited by the availability of effective target-immobilizing devices. Conventional external beam radiotherapy lacks the precsion to allow delivery of large doses of radiation near radiosensitive structures such as spinal cord
Aim:
The Cyberknife is an image-guided frameless stereotactic radiosurgery system that allows for the radiosurgical treatment of spinal lesions. This study evaulted the feasibility and effectiveness of spinal lesions with Cyberknife.
Methods:
In this prospective cohort evaluation of a spine radiosurgery technique,24 spinal lesions in 21 consecutive patients were treated with radiosurgery technique ( 7 cervical,11 thoracic,4 lumber,and 2 sacral). There were 6 benign tumors and 18 malignant lesions. All does plans were calculated on the basis of computed tomographic images acquired from 1.25-mm slices with inverse treatment planning technique. Radiosurgical circular cones ranging in diameter from 5 to 40 mm were used.
Results:
Tumor dose was maintained at 12 to 39Gy to 80% isdose line (mean,24Gy) and 1 to 5 fractioned. Canal volume receiving more than 8 Gy ranged from 0.0~1.23 cm3 (mean,0.2cm3). No acute radiation toxicity or new neurological deficits occurred during the follow-up period ( range,3~6mo;mean,4.3 mo.).Axial and radical pain fully improved in 11 of 13 patient and 2 partial improved than before treatment.
Conclusions: The major potential benefits of radiosurgical ablation of spinal lesions are short treatment time in an outpatient setting with rapid recovery and symptomatic response. This technique offers a successful therapeutic modality for the treatment of a variety of spinal lesions as a primary treatment or for lesions not amenable to open surgical techniques, in medically inoperable patients,in lesions located in previously irradiated sites, or as an adjunct to surgery.