BK Medical bkSpecto, Руководство для продвинутых пользователей

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90 Chapter 8 August 2018 bkSpecto Advanced User Guide (16-01642-01)
Patient Setup
The Patient window for this Pro Package contains a PSA field for PSA Score
parameters:
Table 8-3. Brachy parameters in the Patient window.
Calculating Volumes
Organ volumes can be calculated in several ways. For the formulas used for each of
these calculations, and information about their accuracy, see the
Technical Data
(BZ2100) .
NOTE:
A volume calculation based on a measured ellipse is critically dependent on
the axis of rotation that you choose. See page 50.
Planimetry (Contouring)
For this method, you record several parallel B-mode images that cover the organ to
be measured. On each image, you draw a curve that traces the outline of the structure,
thereby creating a set of parallel section measurements of the structure.
These parallel sections (the outline measurements) are used to estimate the volume
of the structure based on several equally spaced slices.
The accuracy of this method depends on starting the measurements in the correct
place. Start at one end of the organ, where the image shows an area of as close to 0
as possible. After each step, trace the outline of the structure on the image. The
system calculates the volume of the structure between the starting point and each new
image (see Fig 8-4). This is continued until the whole organ has been covered and a
total volume obtained.
Figure 8-4. Longitudinal outline of organ showing the start position for planimetry.
Different stepping units to control the spacing between the sections are available for
use with different transducers.
Parameter Range allowed
PSA 0 – 1000