Saxsons Group

Clinical evidence library · the manufacturer

QA BeamChecker™ Plus — the daily-QA citable backbone.

The QA BeamChecker Plus is built for the daily portion of a TG-142 / TG-198 QA programme. The evidence here has three layers — the AAPM standards the device is designed against, a five-year peer-reviewed trending study that used the device clinically, and the manufacturer technical brochure for the spec audit trail.

8 vented ion chambers — 1 centre + 4 quadrant + 3 energy-ID
±3% / ±5% TG-142 daily output action / no-treat thresholds
2400 MU/min max dose rate — FFF beam compatible
Filter
Daily QA categories defined by TG-142
X-ray output constancy
Electron output constancy
Beam profile constancy
Lasers / ODI / collimator
Door interlock & A/V
Imaging interlocks
Standards 2009
±3% / ±5% daily output constancy — action threshold / no-treat threshold (Klein 2009)

Task Group 142 report — Quality assurance of medical accelerators

Klein EE, Hanley J, Bayouth J et al., Medical Physics 36(9):4197–4212 (AAPM TG-142)

TG-198 — what implementation adds over TG-142
Sample QA forms (daily / monthly / annual)
Procedure scripts per test
Personnel + time estimates per test
VMAT-specific tests not in TG-142
Implementation 2021
12 yrs after TG-142 — first detailed implementation guide; sample QA forms, procedure scripts and VMAT-specific additions

TG-198 — Implementation guide for TG-142 QA of medical accelerators

Hanley J, Dresser S, Simon W et al., Medical Physics 48(10):e830–e885 (AAPM TG-198)

Daily QA dimensions tracked over the 5-year window
Output (photon energies)
daily
Output (electron energies)
daily
Flatness (radial + transverse)
daily
Symmetry (radial + transverse)
daily
Clinical trending 2015
5 yrs of daily output, flatness and symmetry data recorded on a Trilogy linac using a QA BeamChecker Plus

Visual analysis of daily QA results — photon and electron beams on a Trilogy linac over five years

Chan MF, Li Q, Tang X et al., Int J Med Phys Clin Eng Radiat Oncol 4(4):290–299

Beam-modality coverage in a single setup
Photons (60Co–25 MV)
all
Electrons (6–25 MeV)
all
IMAT / VMAT
yes
TomoTherapy
yes
Dynamic wedge
yes
FFF (≤2400 MU/min)
yes
Spec Current
8 chambers 1 centre + 4 quadrant chambers at 7.5 cm from centre + 3 energy-ID chambers; 0.6 cm³ each

Manufacturer technical brochure — 8-chamber ion-chamber array

/ QA BeamChecker Plus brochure (1239-26)

Webinars & Clinical Experiences

A user-perspective talk from a senior medical physicist on running BeamChecker Plus clinically, plus the manufacturer QA Essentials webinar recordings. Click a tile to play in-page.