...tissue.
The term Image-Guided Neurosurgery is often used interchangeably with Frameless Stereotaxy. We think however that the latter term is not entirely suitable since it implies that conventional stereotaxy can be replaced by frameless techniques. In fact, in the actual state of the art, and Stereotaxy cover different, non-overlapping domains of applications. Moreover, the use of the stereotactic frame is not even near to becoming obsolete.
...Technologies
Mississauga, Ontario, Can.
...unit
At the time this thesis was written, a set of basic segmentation tools was already included in the Viewing Wand environment.
...FARO
FARO Medical Technologies, Orlando, Florida, USA
...[#phy_med_im##1#]
This is rigorously true only for linear shift-invariant systems, which is not always the case in medical imaging.
...satisfied
This still holds for MRI but in this case, the sampling is performed in the Fourier domain, and failure to observe Nyquist condition results in foldover in image space.
...of
Since it is the square of the RMS error, it will be refer to as MS error.
...reg_error
The mean rotation and translation can be used to determine 129#129 and 130#130.
...by
It is unusual to use the variance of the square of a variable (that we will call VS) instead of the variance of the variable itself as a measure of its variability. However, there is a simple analytical expression relating the VS of the registration error with the VS of the rotational and translational errors. Such a relationship does not exist between the variance of the first power of these variables. By analogy with the RMS value, we will refer to the RSDS value (Root of the Standard Deviation of the Squared variable) which has the same units the variable for which it is computed. Although the statistical significance of this quantity is not clear, we believe that it constitutes a valid measure of variability that can be compared for different registration experiments.
...steps
To simplify the description of the procedure, we will refer to imaging and surgical spaces.
...machine
Elliott Machinery (Canada) Ltd.
...convention
The rotation is specified by three rotations about the z, x and z axis respectively.
...pulse
If the phase was 304#304 just before the reversing pulse, it becomes 305#305 after if the 306#306 pulse is around the x-axis. This assumes that the phase angle is measured with respect to the x-axis.

Patrice MUNGER
Mon Oct 23 15:09:17 EDT 1995