Biomedical Engineering Reference
In-Depth Information
ridors to a lesion in order to remove it from normal tissue. The multiple methods
for tissue dissection utilize a variety of sharp and blunt as well as cold and
heated tools.
Force-feedback algorithms have been incorporated into a few surgical train-
ing and computerized simulation systems related to blood vessel anastomoses
(21). However, systems that simulate tissue conditions which require tactile ex-
perience and feedback so that a trainee could determine whether it were better to
separate tissue planes sharply with a scissors or knife or bluntly with non-sharp
or rounded instruments have not been developed as of yet. Additionally, it is not
presently realistic to simulate the adverse effects of improper dissection tech-
niques, such as blood vessel disruption, resultant bleeding, bleeding control, and
tissue disruption,
4.
DISCUSSION AND CONCLUSIONS
The field of image-guided surgery today depends on the three-dimensional
co-registration of a variety of high-resolution structural and functional image
sets with the actual physical surgical workspace. Advances in several areas of
medical computer graphics and image processing mated to a variety of three-
dimensional digitizers including robotic manipulators have provided surgeons
with sophisticated tools for precision navigation during operative procedures.
Many of these state-of-the-art systems are used routinely in today's operating
suites.
Most image-guidance systems are based on the co-registration or fusion of
preoperative visual images. A surgeon's view can be enhanced by the improved
lighting and magnification provided by an operating microscope. In operations
executed deep within the body, indirect visual input and substitution can be ac-
complished with video cameras attached to both endoscopes and microscopes.
Such indirect video views of the operative field, if they have high enough reso-
lution, can be enlarged and projected to a flat video screen and provide a partial
immersive virtual-reality environment. These advances alone provide significant
benefits to surgeons in the actual precise and safe performance of many standard
operative procedures. With lightweight head-tracking devices, video projection,
and perspective volume rendering and navigation, this partial immersive envi-
ronment can be made even more realistic.
These systems are important for training neophyte surgeons in both opera-
tive planning and execution. Similarly, they can assist trained surgeons in prac-
ticing and maintaining their skills. However, until more sophisticated haptic
systems are available to substitute for the surgeon's sense of touch, these devices
cannot substitute for actual tissue manipulation either in the surgical training
laboratory with animals or in the operating suite as surgical assistants during
operations on human beings. Nevertheless, with modern advancements in bio-
