Biomedical Engineering Reference
In-Depth Information
FIGURE 15.8
Intraoperative image updating algorithm based on model calculated deformation.
can be used to update the undeformed preoperative images. Implementation in
3D is reasonably straightforward, as illustrated in Color Figure 15.10.* These
calculations show an interesting tissue bulge in the retraction direction. Figure
15.11a presents an intraoperative CT image of the
in vivo
pig brain under retrac-
tion. The motion of the blade and implanted bead markers is evident along with
a bulging of tissue in the retraction direction as suggested by the model. Note
that in this case tissue on the “back side” of the retractor appears to adhere to
* Color Figures follow page 22.
