The role of a radiopaque peri-rectal hydrogel spacer in aiding accurate daily image-guidance for prostate stereotactic radiotherapy oleh Oded Icht, Oded Icht, Shir Schlosser, Shir Schlosser, Miriam Weinstock-Sabbah, Mor Rephael, Dimitri Bragilovski, Assaf Moore, Assaf Moore, Tzippora Shochat, Dror Limon, Dror Limon, Elisha Fredman, Elisha Fredman