Monteris Medical Neuroblate, Инструкция по эксплуатации

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NeuroBlate® System Instructions for Use
80469 Rev D – Nov 16, 2018
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Figure 8.8.3.21: Noise Mask and Reference Point Selection
Once MR images begin arriving from the MRI (approximately every 8 seconds), the initialization
phase will compute a noise mask and allow for reference point selection. The software receives
data and updates the view with an orange-colored overlay indicating mask component pixels as
shown in Figure 8.8.3.21.
The mask is a circular region (6 cm diameter) surrounding the LDP. It represents a sub region of
the acquired MR images. Any data outside this region is ignored. The MR data measurements
within the mask are analyzed and any pixel locations containing excessive phase noise will not
be used for temperature measurement. Pixels not used for temperature measurement are
cleared or rendered transparent in the mask overlay as shown above where the pixels in the
center of the mask in the first two image panes are dropped due to LDP artifact.
As the MR acquisition continues, the user must select a minimum of 8 reference points
surrounding the treatment area within each view as reference points. These reference points
map out any proton resonant phase drift inherent to the MRI scanner and compensates for any
phase drift to help provide accurate thermal imaging.
•
Select
Set Points
Under the
Noise Masking
heading on the M*Vision the right menu bar
•
Select 8 reference point at the periphery of the overlaid, orange Noise Mask in each of the
three displayed image monitoring view panes
These view-planes surround the intended thermal delivery area (Figure 8.8.15). Ensure the
points are picked only within actual brain tissue (grey or white matter) avoiding sulci, blood
vessels, ventricles and bone. To delete a reference point, right click on the reference point and
click “delete”.
36.5°