Ayala-Peacock DN, Peiffer AM, Lucas JT, Isom S, Kuremsky JG, Urbanic JJ, Bourland JD, Laxton AW, Tatter SB, Shaw EG, Chan MD. A nomogram for predicting distant brain failure in patients treated with gamma knife stereotactic radiosurgery without whole brain radiotherapy. Neuro Oncol. 2014 Sep; 16(9):1283-8.