EASY CUBE - RW3 phantom for Linac quality assurance

RW3 Linac phantom EASY CUBE

EASY CUBE supports QA measurements in dosimetry and beyond in the field of radiation oncology. The RW3 Linac phantom can be used in combination with irradiation detectors like ionization chambers, radiosensitive films and TLDs. The detectors are positioned inside the phantom with appropriate adapters which consist of the same RW3 material as the phantom.

The unique multi-colored grid eases inital postioning during set up and orientation during QA tasks and therefore reduces misalignment risks.

Quality assurance at Linac with RW3 phantom

QA OF HIGH-ENERGY PHOTONS AND ELECTRONS ON LINACS

  • Measurements with a homogeneous,
    standardized RW3 phantom with properties equivalent to water
  • Measurements with irradiation detectors
    from all well-known vendors by use of optional adapters
  • Measurement of dose distributions
    which have been computed for the phantom within the frame of radiation therapy planning
  • Measurement of dose distributions
    which have been computed for the phantom in connection with intensity-modulated fields
  • Measurement of dose distributions
    which have been computed for the phantom concerning stereotactic irradiation

QUALITY ASSURANCE ON COMPUTER TOMOGRAPHS (CT)       

  • Cross-checking of Hounsfield values
    measured by a CT scanner
  • Cross-checking of CT scans
    for geometric distortion
  • Cross-checking of table coordinates
    displayed by a CT scanner
  • Cross-checking of coordinate system
    of a CT scanner

Movie: EASY CUBE Features and Modules for Quality assurance

Extension MODULES

EASY CUBE - THE CORE
The base for all setup variants, except of the head module
RW3 phantom for various applications

DIFFERENT SHAPES – DIFFERENT POSSIBILITIES

By means of various extension modules, EASY CUBE can be shaped into different Linac RW3 phantoms for different applications.

  • Multi-modular design
  • Different configurations possible
  • Robust fixation of plates and inserts
  • Reproducible measurement set-up

 

 

CYLINDER MODULE F or S

EASY CUBE with Cylinder Module

The combination of EASY CUBE with the Cylinder Module F or Cylinder Module S forms a cylinder phantom with a diameter of 320 mm. The Cylinder Modules also consits of RW3 Material.

 

F: Fillable
S: Solid

HEAD / OVAL MODULE F

Head Module
Head Module + EASY CUBE = Oval Module

As with EASY CUBE, the Head / Oval Module F is hollow and can be filled with detectors and compensation elements.

This arrangement is especially suitable if radiation is to hit the phantom from different angles. It serves to prevent artefacts resulting from radiation hitting the edges of the phantom.

The Head / Oval Module F can be used to simulate a human head by fixating the two half cylinders to one another with assembly plates. The result is a cylindrical phantom, 180 mm in diameter and 180 mm in height.

BODY MODULE F or S

Body Module

For simulation of the entire human torso (trunk) the Body Module S can be combined with the EASY CUBE. The Body Module S is comprised of two solid half RW3 cylinders and 16 body shaped distance plates with needles for film alignment (15 plates each 10 mm thick, numbered from 1 to 15, one plate 5 mm thick).

ACCESSORIES

A MODULAR EQUIPMENT SOLUTION

Inhomogeneous inserts

INHOMOGENEOUS INSERTS

For calibration of Hounsfield values, various inhomogeneous inserts similar to fat, muscle, lung and bone fabrics are available. Artificial inhomogeneities like metal prostheses can be simulated as well. The inhomogeneous inserts can be freely positioned inside EASY CUBE using the compensation elements.

 

 

Adapter for different ion chambers
Adapter plate for radiochromic films
Adapter plate for TLDs

DETECTOR ADAPTERS

  • Adapters for different ionization chambers: One or more detector adapters corresponding to your configuration, e. g. for detectors already in your possession allow positioning at the desired measurement position.
  • Adapter plates for radiochromic films: Radiochromic films can be placed inside EASY CUBE using compensation plates with a milled cavity. 
  • Adapter plates for TLDs: Different adapter plates are available for measurements with thermoluminescent dosimeters (TLD). The square adapter plates (160 mm edge length) are 10 mm thick. Depending on the TLD type, the adapter plates are equipped with bore holes, rods, or circular pits, so called “chips”.


Stereotactic localizer plates

STEREOTACTIC LOCALIZER PLATES

Stereotactic localizer plates with integrated metal wires are available for the measurement of stereotactic coordinates. The stereotactic localizer plates are fastened with screws to the surface of the EASY CUBE. 

Compensation plates and bars

COMPENSATION ELEMENTS

  • Compensation plates of different thicknesses
  • Compensation bars and spacers in different dimensions

Levelling plate

LEVELING PLATES

Using the leveling plates, available in two different sizes, EASY CUBE and its extension modules can be fixed and precisely positioned within the application environment.

EASY CUBE transport and storage case

TRANSPORT AND STORAGE CASE

EASY CUBE together with the different modules of choice will be delivered with a dedicated transport and storage case.

END-TO-END TEST

Easy and precise alignment of the EASY CUBE by means of cross-hair lasers and grid pattern.
Easy and precise laser alignment of the EASY CUBE

QA THROUGHOUT THE RADIATION TREATMENT CHAIN
With EASY CUBE we offer efficient QA from imaging to beam delivery which is cost-effective and fast.

WHY END-TO-END TESTS?
End-to-end testing is a methodology used to test whether the treatment chain is performing as designed from start to finish.

With the increasing complexity of external beam therapy, so-called End-to-End tests are intended to cover all steps from therapy planning to follow-up to fulfill the high demands on quality assurance. End-to-end tests are used to measure the overall accuracy of the radiation therapy chain, excluding patient specific factors.

An end-to-end test is a prerequisite to the overall success of any IGRT to analyze potential errors accumulated by individual devices and processes in the treatment chain.

EXAMPLES FOR QA WITH EASY CUBE

End-to-End tests need to be developed and coordinated closely to your individual clinical processes. Here are some options for your quality assurance througout your treatment chain.

  • QA OF CT PARAMETER
    Starting with the alignment as preparation of the treatment planning CT, the EASY CUBE phantom can be specifically configured for your patient case, e.g. using extension modules and accessories like inhomogeneous inserts.
    Measurements of CT parameters like HU values and phantom dimensions can be processed.
  • QA OF DATA TRANSFER
    As target volumes and OARs often are contoured at special contouring stations, the CT objects have to be sent to these contouring stations via a specified transfer protocol.
    A correct data transfer is mandatory for further use and can be checked with generated EASY CUBE data. 
  • QA OF TPS
    In case of contouring and treatment planning are processed at different systems, the transfered data including the structure set can be checked again and errors can be evaluated.
    An individual patient treatment plan can be calculated at the TPS under consideration of the invidual configured setup of the EASY CUBE.
  • QA OF TREATMENT POSITIONING
    The EASY CUBE phantom can be aligned by use of imaging devices (e.g. EPID) of the treatment unit.
    Produced images can be checked regarding mentioned image parameters and registered to the treatment planning CT.
    Evaluated shifts can be checked to the realized table and gantry movements.
  • QA OF DOSE
    Interesting values of dose distribution can be measured in combination with appropriate detectors at the Linac. Planned irradiation can be checked by precise positioning of various detectors.

Technical Data

MaterialWater-equivalent white polystyrene “RW3” for high-energy photon and electron radiation
Energy rangePhotons 60Co – 25 MV
Electrons 4 – 23 MeV
Material compositionPolystyrene (C8H8) with admixture of 2.1 % ± 0.2 % TiO2
Mass density1.045 g /cm3
(Z / A)r value0.536
Electron density 3.386 × 1023 e/g
Electron concentration3.39 × 1023 e/cm3
Dimensions
EASY CUBE180 × 180 × 180 mm
Cylinder Module320 mm diameter, 180 mm height
Head / Oval ModuleHead: 180 mm diameter, 180 mm height
Oval: 360 mm length, 180 mm width, 180 mm height
Body Module360 mm length, 335 mm width, 180 mm height