VIEWRAY MRIdian System 4.5 - Patient Load Position

330 MRIdian® system L-0009 Release 4.5 ViewRay, Inc.
Chapter 8: Patient Set-Up
The GO TO ISO button behavior is dependent on the stored couch position
value in the PHS memory.
If a stored couch position is loaded in the PHS memory
, only certain movements are available
from the control panels. These movements include GO TO Home, GO TO Plan, and GO TO
ISO.
The Plan indicator can be used to tell if the PHS has a stored couch position in memory. If the
Pl
an indicator is lit (yellow or green) there is a stored couch position in the PHS memory. If it
is determined the stored couch position needs to be changed use the Cancel + ISO button
combination to clear the stored couch position from the PHS memory.
Each treatment plan contains an isocenter poin
t defining where the patient is positioned
relative to the machine isocenter. Along with the plan isocenter the couch position is entered
on the Points screen so the couch can be modeled properly during dose calculation. This
couch position value is sent to the PHS when the plan is loaded from the TPDS and becomes
the stored couch position for this plan and future fractions.
During the Positioning stage of treatment an adjustment to the couch may be determined
based
on image registration results, the new couch position can be sent to the couch using
the Send Shift to Couch button on the TPDS display and pressing Enable + ISO on the TCP.
This action will move the couch to the intended position and update the stored couch
position in the PHS memory. This stored position will only remain in PHS memory for this
session.
If you want to update this stored couch position for future fractions it can be saved with the
plan b
y selecting the Acquire Couch Position button in the TPDS. See “Saving the Patient’s
Couch Position” on page 348.
8.8 Patient Load Position
The PHS may be lowered below the home position to facilitate patient loading and unloading.
The PHS must be in the home position to enter the loading mode. With the table in the home
position pressing Enable + the Z- jog control will move the PHS lower. When in this loading
mode vertical movement is possible with the Z+ and Z- jog controls. The PHS can be returned
to the home position height with the Z+ jog control or Enable + Home button.
Enable + Home must be pressed after being in the load position be
fore additional movement
is permitted even if the PHS was moved to the home position with the Z+ jog control.