Reducing 4D CT imaging artifacts at the source: first experimental results from the respiratoryadaptive computed tomography (REACT) system

Reducing 4D CT imaging artifacts at the source: first experimental results from the respiratory
adaptive computed tomography (REACT) system: Breathing variations during 4D CT imaging often manifest as geometric irregularities known as

respiratory-induced image artifacts and ultimately effect radiotherapy treatment efficacy. To reduce

such image artifacts we developed Respiratory Adaptive Computed Tomography (REACT) to trigger CT

acquisition during periods of regular breathing. For the first time, we integrate REACT with

clinical hardware and hypothesize that REACT will reduce respiratory-induced image artifacts ≥ 4 mm

compared to conventional 4D CT. 4D image sets were acquired using REACT and conventional 4D CT on a

Siemens Somatom scanner. Scans were taken for 13 respiratory traces (12 patients) that were

reproduced on a lung-motion phantom. Motion was observed by the Varian RPM system and sent to the

REACT software where breathing irregularity was evaluated in real-time and used to trigger the

imaging beam. REACT and conventional 4D CT images were compared to a ground truth static-phantom

image and compared ...