HELMET: a hybrid machine learning framework for real-time prediction of edema trajectory in large middle cerebral artery stroke by Phillips, E, O'Donoghue, O, Zhang, Y, Tsimpos, P, Mallinger, LA, Chatzidakis, S, Pohlmann, J, Du, Y, Kim, I, Song, J, Brush, B, Smirnakis, S, Ong, CJ, Orfanoudaki, A