“…So far, most of the work emphasizes on evaluating the registration quality using plastic phantoms [8], [9], [10], ex vivo spine anatomy [11], or animal cadavers including sheep [12], [13], [14] and pigs [15], [16], [17], [18], [19]. The few papers evaluating feasibility on clinical data have focused on needle guidance applications [20], [22], [22], [23]. Although Winter et al [24] evaluated their method on data collected on 5 patients undergoing surgery, their validation was limited to assessing the registration robustness.…”