We use binocular vision every
day in everyday life. There are few surgeons who would prefer living
- much less operating - with only one eye. Binocular microscopes are
in common usage in microvascular surgery, as are surgical loupes that give
good stereoscopic vision. Is there any reason that we should persist
in viewing our imaging with one eye? Do we continue listening to our
music using monophonic gramophones?
The ability to perceive images
tridimensionally can add to a overall understanding of a bony problem
(the "personality" of the fracture or deformity). Radiostereogrammetrical
analysis (RSA) to measure prosthesis migration is currently the main
use of stereoscopy in orthopaedics. RSA devices are very accurate,
often with accuracy of depth measurement in a stereo pair of 1mm or
less. Harnessing this ability to perceive depth in other clinical
situations has a lot of potential. When using stereoscopy
the limitations of the technique must be kept in mind - it is an adjunct
to currently available imaging modalities, not a replacement.
Stereoscopic endoscopy is an
area which is being opened up by general, urological, and cardiothoracic
surgeons. There is potential use in orthopaedics, but due to current
technical and cost limitations, we are not actively looking at development
in this area at present.
Software for rendering volumetric CT and MRI data in stereo is available: see the "opacity based rendering" page for details and a couple of quick tutorials on the subject.
Stereoscopic visuallization is
a tool that is mainly useful in getting images with depth information as
well as increasing the perceived resolution of the image by using both eyes.
Applications need only be limited by one's imagination.