University Hospital Southampton poster details use of IQM to verify single-isocenter multiple brainmets treatments.
Southampton General Hospital, part of the University Hospital Southampton, is the largest clinical center of the NHS Foundation Trust. The radiotherapy center is equipped with 6 state-of-the-art Elekta linear accelerators making University Hospital Southampton one of the largest radiotherapy centers in the south of England.
Each treatment room is equipped with the complete IQM infrastructure allowing the medical physics team to utilize their 2 IQM detectors with each of their 6 Elekta linear accelerators (see IQM attached to Elekta Versa HD linac head for measurements at University Hospital Southampton below).
The Medical Physics team optimized the IQM calculation algorithm for the verification of single isocenter multiple brainmets (MBM) SRS treatment techniques (see Brainlab Elements single isocentre treatment plan for 7 MBM below)..
They published their results in a poster titled:
The poster was presented at the UK Imaging & Oncology (UKIO) 2023 conference in Liverpool, UK from 5th to 7th of June 2023.
The new IQM SRS QA expansion supports field sizes as small as 0.3cm x 0.5cm. The Medical Physics team used 20 clinical test plans consisting of a total of 128 arcs and 1903 beam segments to evaluate the agreement of measurements with the calculated reference signal (see distribution of measured data points by segment field size and distribution of average segment-by-segment deviation by segment field size below)
All 20 clinical test plans passed both watch and action level thresholds for cumulative signal as well as the action level threshold for segment-by-segment signal. One quarter (5 of 20) plans showed a watch-level segment-by-segment deviation.
Based on this evaluation, the Medical Physics Team at University Hospital Southampton set the watch level threshold to (symmetric) +/-3% and the action level threshold to asymmetric -6.3% and +4% for all routine stereotactic patient specific dosimetry.
We congratulate University Hospital Southampton on their clinical rollout of the IQM system for SRS multiple brainmets plans.
Check out the poster and the video presentation for more information.