Ways to measure the amount of Beam
what is
Treatment Complete (Spot map delivered)
what is dDone
Disables interlock on max number of retries (nominally 64pC)
what is Pulse Retry Limit Error
Stitching two lateral fields together to make a larger (or longer) field (e.g. for treating a spine).
What is Match Fields (“Feathering”)
MLIC
multi-layer ion chamber
What is a device for quickly making Integral Depth Dose (IDD) measurements of pristine Bragg Peaks
8pC/pulse (~50 million protons)
What is the max pulse charge
Treatment Time T
Time in the state Beam On is less than 20% more than the prescribed time.
dTime
This will turn off (disable) the pulse to pulse correction in 2.4.0+.
What is Pulse Position Correction:
An island (or perhaps more accurately, a donut) plan is one in which there is a region meant to receive no dose that is completely surrounded by a region of dose.
What is an Island
At the end of each treatment, an internal record is produced that contains all of the recorded information for that beam delivery
What is M-DRHC (aka: Mevion (non-DICOM) Treatment Record, Dosimetry Record)
A lookup table that tells the system to fire to get the desired pulse charge
What is the pulse width curve chart
Beam Paused Timeout
System has not been in the state “Beam Pause” for more than the configurable time.
What is DP max
Disables layer correction (no shift)
What is Layer Correction:
If no beam (or very little beam) comes out, it fires the ion source again right away instead of wasting time having to come back to that spot later
What is Adding automatic retries
When treatment plans are exported from the TPS to the OIS, this intercepts the plans, breaks the spots into pulses and reorders the spots to accommodate the adaptive aperture and the range shifter’s
what is the Spot Map Converter (SMC)
When The Dosimetry modules samples the background for a fixed period of time to determine the mean (average) of the noise floor
What is the sound you hear when you turn the key to shoot a beam and before you push the beam enable button
Spot Position
Spot location (in mm, referred to isocenter) is within the configured tolerance at isocenter (TICs). Used for:
What is dPos
Disables retry when pulse is below minimum charge (usually set to 0pC, effectively off)
What is Pulse Retry for Low Charge
/Dosimetry.xml: InplaneSlope, CrossplaneSlope, Offset for DosX and DosY, US and DS, at each 22.5-degree gantry angle
What are Relevant XML Parameters
How the TC will recognize it as being a plan that has passed through the SMC,
What is a Tag
The adjustments made when a system’s Pulse Width Curve can change as the system warms and cools, so there is an automated
What is scaling PWCs
Layer Shift
Requested one-time X or Y layer shift is below configurable value.
what is dShift
Disables PWC scaling – always uses loaded PWC
What is Dynamic PWC
You could do it with a single field, but the entrance dose (which you wish was 0%) would be 66% of the tumor dose. By dividing this into 2 uniform, parallel, opposed fields
What is Non-Uniform Parallel Opposed
Just prior to pulse delivery, the XYZ controller sends out the integrate signal for this reason
What is back ground Subtraction