Biomedical Engineering Reference
In-Depth Information
1.
INTRODUCTION
The goal of medical surgery has not changed since the time of Hippocrates.
That is, every surgeon seeks to relieve a patient's diagnosed complaint without
causing harm. In this endeavor, both daring and caution are required—first to
plan, and then to execute the most precise surgical procedure that will result in
removing the underlying pathology or interrupting its pathways. Once planned,
the success of each operation depends upon a range of external sensory inputs as
interpreted through stored experiential memories to produce finely honed hand
motor skills and extended periods of focused attention. In this context, the pre-
dominant senses involve vision and touch, but sound and smell are also signifi-
cant. The equanimity to perform these acts of delicate balance comes from
rigorous training and continued practice, awareness of scientific advances, not
only in medicine but also in other disciplines, and the testing and incorporation
of appropriate new technologies for the particular surgical procedures. In recent
years surgeons have worked closely with bioengineers and computer scientists
to design virtual-reality environments that simulate the actual surgical work-
space in order to create and test realistic training and practice platforms.
How far are we from the development of an actual "surgical holodeck?"
2.
BIOMEDICAL BACKGROUND
2.1. Perspective
This review is biased to neurosurgery because the foundations for creating a
"surgical holodeck" are based initially on advances in brain imaging coupled
with hundred-year-old techniques of stereotactic brain surgery, i.e., localization
of the physical three-dimensional position of structures making up the brain. In
the past few decades, the scientific and practical advances of neurosurgical
stereotaxy have resulted in an enormous wealth and breadth of structural and
functional data about the brain. With each incremental advance, these image
databases have promoted increasingly more sophisticated techniques of surgical
navigation, leading to "fail-safe" surgical simulation environments similar to
those created for training and assessing the competence of airline pilots. Using
computer-generated and stored databases, today's neurosurgeon routinely navi-
gates within a Cartesian coordinate system that targets structures in the human
brain to both define and alter function.
2.2. Historical Context
In most parts of the body, routine surgical operations were traditionally per-
formed through openings that allowed direct visualization of the abnormality to
be removed or altered. Obviously, however, the cranial vault is not conducive to
wide, exploratory openings. Therefore, from the outset, neurosurgeons necessar-
ily relied on physical and neurological examination as correlated with a range of
