Table 5.

Approximate Time Requirements for the Tasks in Image-guided Liver Surgery

Task	Approximate time
Preoperative tasks
Manual segmentation	3–4 h
Automatic segmentation	15 min
Marching cubes	5 min
Radial basis function Surface Fitting	5 min
Range scan calibration	5 min
Intraoperative tasks
Landmark localization and registration*	30 s
Surface acquisition with tracked probe*	1–2 min
Range scan setup (not optimized)	1–2 min
Surface acquisition with range scanner*	15–20 s
ICP registration using k–d trees	1–5 min
Modeling with finite element method	2–3 min
Image deformation	2–3 min

^*These tasks need to be performed during an apneic period.