Determining radiographic outcome after spine radiosurgery--not as straightforward as one might think.

<bold>Commentary On: </bold>Spratt DE, Arevalo-Perez J, Leeman JE, Gerber NK, Folkert M, Taunk NK, et al. Early magnetic resonance imaging biomarkers to predict local control after high dose stereotactic body radiotherapy for patients with sarcoma spine metastases. Spine J 2016:16:291-98 (in this issue). [ABSTRACT FROM AUTHOR]