TRiP98 field command

field id / file()     list           target()                    debug
           import()   delete         gantry() couch()
           export()   display        chair()
           read       inspect        stereotacticcoordinates()
           write      reset          fwhm(6)
                      new            rastersteps()
                      reverseorder   zsteps(1)
                                     beam()
                                     weight(1)
                                     contourextension(0.6)
                                     doseextension(1.2)
                                     projectile(C)
                                     bev()
                                     nolateral
                                     raw
                                     dosemeanlet
                                     algorithm(cl)
                                     bioalgorithm(cl)

Purpose

Parameters

id

Required field identifier. Must be a number 0<id<99 for new and read, may be wildcarded for the other options.

file(file)

For input and output operations the name of a file with raster scanner data. Note that with multiple field ids specified the latest overrides the previous ones.
The spring 2001 release (0102) also supports the old CAVE A format (see example below).

import()

Not yet implemented.

export(fmt)

Exports specified field in some non-native format, at present only gd is implemented to export for the gd plot program.

read

Reads raster scanner data in file into field id. If couch and gantry angles are given, they overwrite those from the file.

write

Writes raster scanner data of field id to file

list

Lists field id.

delete

Deletes field id.

display

Displays field id. Not yet implemented.

inspect

Show some internal info about the field id.

new

Create a new field id for optimization.
Note that a CT, a target VOI, a SIS table and a HLUT must exist.

reverseorder

Write raster scanner data with low energies first.

reset

Resets particle numbers in the field id.

target(x,y,z)

Specifies target (isocentre) coordinates, in CT system. If omitted, they are computed from the target contours. In this case, valid VOIs have to be defined.

gantry(gantryangle)

Gantry angle. At GSI this should be -2.203 degrees.

couch(rotation[,tilt])

Couch rotation and tilt (optional) angle. At GSI the default rotation (zero position) should be -180 degrees.
The tilt angle is optional (zero by default), but allows to rotate the couch around its z axis, in mathematically positive sense.

stereo(string)

Stereotactic coordinates. string is passed to the raster data file.

chair(rot,tilt)

Prepare a field for GSI's patient chair, with specified rotation and tilt angles. Overrides couch(), but uses the gantry() setting.

fwhm(focus)

Desired focus value for the beam spot (FWHM, in mm). It is checked against the values available in the SIS table. For each energy slice the smallest value >= <focus> is selected.

rastersteps(dx,dy)

Pair of numbers specifying the raster stepsize (mm) in x- and y-direction. If omitted, it is calculated from fwhm() by applying a factor defined as part of the scanner capabilities and controllable by the scancap command.
If steps are specified, they should be not larger than 1/3 times the fwhm().

zsteps(dz)

Specifies the approximate spacing (mm) between subsequent peak positions. From this and from the minimum and maximum water-equivalent depth the necessary energies are derived. Due to the finite list of energies in the SIS table, exact spacing can't be guaranteed.

beam(beamlist)

List of beam energies (comma separated) used for new field id. Overrides zsteps()

weight(w)

Weight for new field id. Not yet implemented.

contourext(cext)

For new field id all raster positions which are inside the target volume are "extended" by cext times the true focus value for the respective energy slice. This should allow better dose conformation when this field is optimized.

doseext(dext)

For new or read fields only. dext times the true focus value for the respective energy slice specifies maximum distance from which dose contributions are accepted.
dext=1.2 roughly corresponds to 3 sigma, dext=0.85 to 2 sigma.

proj(proj)

Specifies projectile to be used. Should be C (carbon).

bev(x,y)

Specifies dose calculation in the water-equivalent system along a line given by the raster coordinates x,y (mm, Beam's Eye-View). For x,y="*" the middle position of the raster is chosen. The physical dose and the projected sum dose is calculated. If the necessary tables exist, the biological dose is calculated too. Data is output automatically to file.

dosemeanlet

If specified, the mean and the dose-mean LET are calculated and exported as well. This requires the existence of a valid dE/dx table.

algorithm(alg)

Selects algorithm for beams-eye-view dose calculation. Same choices as for dose calculation:

• classic or cl (default)
• allpoints or ap
• multiplescatter or ms

bioalgorithm(alg)

Selects algorithm for biological effect calculation.

• classic or cl (default)
• lowdose or ld

nolateral

For the bev() dose calculation, do not consider lateral dose contributions from finite beam width or small angle scattering. This is for backward compatibility with the "old" TRiP versions.

raw

Writes raster slices in raw, unprocessed mode, i.e. no suppression of positions with particle numbers of zero.

debug

Debug switch. Lots of output !

Remark

Examples

1. field 1 /new raster(2,2) zstep(1) targ(20,20,70) doseext(1.4) contourext(0.0)
   

   Creates a new field

2. field 1 /write file(xyz.rst)
   field 1 /bev(*) file(xyz.bev.gd)
   

   Outputs scanner data, then the dose on the centre line in beams-eye-view.

3. sis / dummy
   rangeshifter /slices(8,4,2,1)
   field 1 /new raster(2,2) zstep(1) beam(200,170) targ(20,20,70) doseext(1.4) contourext(0.0)
   optimize /field(1)
   

   Creates and optimizes a new field for CAVEs without MEFI operation. A range shifter is used for passive energy variation. Only two basic primary energies (200 and 170 MeV/u) are available.

4. field 1 /read file(xyz.allcuts.dat) fwhm(5)
   

   Reads old CAVE A scanner data. Files xyz.cutnn.dat are assumed to exist. Since the old CAVE A format does not support a beam focus value it must be supplied extra.