Fig. 1
Representative dose distributions of spine stereotactic ablative radiotherapy cases (patient #29 and #23) for thoracic (T) and lumbar (L) spines, respectively, are shown. Dose distributions of volumetric modulated arc therapy plans generated by a progressive resolution optimizer (VMARPRO) (a) and by a photon optimizer (VMATPO) (b) for patient #29 are shown. For patient #23, dose distributions of VMATPRO (c) and VMATPO (d) are also shown. Doses are depicted by color wash with 7 Gy (the lowest dose) in blue, and 20 Gy (maximum dose) in red. The lowest dose, 7 Gy, was chosen to represent the minimum doses inducing the radiation myelopathy