QA BeamChecker™ Plus

The QA BeamChecker Plus is a reliable and uncomplicated daily QA instrument for linear accelerators and TomoTherapy® systems. With wire-free technology, integrated build-up, and automatic energy detection, radiation therapists can quickly and easily perform daily QA.

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Multiple vault capability

Up to nine treatment rooms can be managed with just one QA BeamCkecker Plus. Using the Communication Software, a complete set of linear accelerator or TomoTherapy Hi-Art system baselines can be created for each room. Once a room has been created, it becomes selectable from the QA BeamChecker Plus in any mode, including Wire-free. When performing daily QA simply select the desired room and the QA BeamChecker Plus automatically detects the energies provided by the operator.

Wire-free technology

Simplifies set-up and allows technicians to quickly complete daily QA procedures. Wire-free mode displays a pass/fail indication for each energy via a large, brightly lit display, clearly visible from the patient monitor. Unlike some devices, you do not have to control the QA BeamChecker Plus from the PC, allowing for a wire and software free solution right out of the box. No cables means less clutter in the accelerator room, no cable replacement costs, and a safer work environment, no accidental tripping or pulling the instrument off the couch.

Automatic energy detection and reset

The QA BeamChecker Plus automatically detects the energy type and simultaneously determines beam constancy, flatness, and symmetry. Once complete, the data is saved for later review and the instrument re-arms itself within 10 seconds for the next energy.

Integrated build-up

Integrated build-up for all supported energies eliminates the need to enter the treatment room between measurements. After a quick flip and simple button press, the QA BeamChecker Plus switches between photon or electron mode and inverts its display. The photon side provides a 3.5cm of water equivalent material with 1.5cm on the electron side, so there are no extra pieces to keep track of.

TomoTherapy QA capability

The QA BeamChecker Plus allows radiation therapists to perform daily QA checks (D1-D6) for helical TomoTherapy systems, recommended by Fenwick et al., 2004

  • output constancy (D1)
  • energy constancy (D2)
  • lateral profile constancy (D3)
  • output ramp up time (D4)
  • combined dosimetric check (D5)
  • laser accuracy tests (D6)

  Test
description
Tolerance Test
mode
Field
used
Detector
D1 Output
Constancy
+/-2% Static Static 5 x 20cm One centred 0.6cc
ion chamber
D2 Energy
Constancy
+/-2% Static Static 5 x 20cm
TPR 9.7/3.5
Two 0.6cc
ion chambers
D3 Lateral
Profile
Constancy
+/-2% Static Static 5 x 20cm Three 0.6cc
ion chambers
D4 Output
Ramp Up
Time
<10sec not
applicable
not
applicable
Integrated
detector
system
D5 Combined
Dosimetric
Check of jaw
width,
couch speed,
leaf latency,
output and
leaf/gantry
synchronicity
+/-2% Dynamic Dynamic
modulated
treatment
Three 0.6cc
ion chambers
D6 Laser
Accuracy
+/-1mm Beam off not
applicable
Alignment marks,
Precision TomoTherapy
Levelling Platform

Once custom static and 4D treatment plans are developed, they are delivered to the QA BeamChecker Plus to establish baselines. Simply deliver these plans each day to complete the daily QA procedure. Only two exposures are needed to perform these tests; one in a static mode, with the gantry fixed in a vertical position and one in a dynamic mode. No re-positioning of the QA BeamChecker Plus is necessary between the two exposures. Additionally, multiple static and dynamic plans can be developed to test each jaw width setting individually.

The precision TomoTherapy levelling platforM levels the QA BeamChecker Plus on the TomoTherapy system treatment couch to allow for laser accuracy measurements. These measurements are done between virtual isocenter and real isocenter using MVCT images to compare with lead BBs embedded within the QA BeamChecker Plus. Laser alignment accuracy and coincidence are tested between seven lasers using alignment marks.

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Rotational and dynamic QA

Providing a combined dosimetric check, the Dynamic 5 Channel mode is ideal for rotational testing. By accommodating custom tests for IMAT, VMAT, dynamic wedge, and others, checking and trending daily changes in beam output is now easier than ever. This mode provides a combined dosimetric check of the treatment system, allowing an output constancy check of each temperature and pressure corrected detector within the instrument.

After creating a CT image of the QA BeamChecker Plus, develop a custom plan for each energy used by the treatment machine. Create a baseline for each plan and repeat daily fora fast, easy check of the radiotherapy treatment system. Up to 25 plans can be developed for each treatment room., so a highly customized QA procedure can be developed to test multiple aspects of the system such as different energies and gantry rotation speeds.

This mode can also be used to perform test of enhanced dynamic wedges and tissue phantom ratio measurements. With the QA BeamChecker Plus, it take only one tool to perform multiple QA tasks, saving time, money and providing more confidence in your daily routine.

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