1:The Modeling Experiment Of Spinal Tumor Afterloading Radiotherapy 2:The Elementary Research Of Etiology Of Fibrous Dysplasia Of Bone

The modeling experiment of spinal tumorafterloading radiotherapyAbstractBecause of vertebral venous system's distribution, the metastatic tumor of skeletal system always distribute centripetally, which result in the vertebral metastases occupy more than 60% in malignant neoplasms of spine. Spinal tumor is one of thorny problem in the orthopaedics. Therapeutics of this disease adopts colligation treatment, which depend mainly on operation. Because of the complicated anatomical structure of spine, it's difficult to resect tumor completely.In spinal tumor treatment, radiotherapy is not only a very effective way of relieving pain, but also preventing progressive neurologic dysfunction, retarding tumor growth, and preventing local recurrence. Document reports show that radiation therapy reduces pain in 70% to 90% of patients, improve motor function in 45% to 60%, and reverses paraplegia in as many as 11% to 16%. The effect of radiation therapy on recovering neurologie function has no significant difference comparable to surgery, so radiotherapy is an effective approach to spinal tumor. But the spinal tumor's radiation treatment scheme is restricted by spinal cord tolerance limit, and because spinal cord belongs to late response tissue, clinic treatment use conventional fractionation, even hyperfractionation to increase dose limitation and improve therapeutic ratio.This experiment is to investigate a radiotherapy method—remote afterloading brachytherapy system, engaging in measuring the spinal cord irradiation dose when this system applied to spinal tumor, so as to appraise the feasibility of this method applied to spinal tumor.The results show that the theoretic outcomes of afterloading planning system is markedly difference from that of actual measurements with thermolumineseent dosimeer, and there are probably five reasons for the difference So I think we should be cautious about the application of afterloading system in spinal tumor. Moreover, along with new technique of radiotherapy, 3 Dimensional Conformal Radiation Therapy will be one choice of spinal tumor radiation therapy.