[1] Ecole Polytech, Montreal, PQ, Canada
[2] CHUM, Neuropathol, Montreal, PQ, Canada
[3] McGill Univ, Neurosurg, Ctr Hlth, Montreal, PQ, Canada
[4] CHUM, Opt Engn, Ctr Rech, Ecole Polytech, Montreal, PQ, Canada
[5] McGill Univ, Ctr Hlth, Dept Pediat Surg, Div Neurosurg, Montreal, PQ, Canada